CN115001183A

CN115001183A - Magnetic suspension switched reluctance motor and suspension force control device, method and system thereof

Info

Publication number: CN115001183A
Application number: CN202210751380.7A
Authority: CN
Inventors: 刘泽远; 王振; 张文峰; 杨艳; 刘程子
Original assignee: Nanjing University of Posts and Telecommunications
Current assignee: Nanjing University of Posts and Telecommunications
Priority date: 2022-06-29
Filing date: 2022-06-29
Publication date: 2022-09-02

Abstract

The invention discloses a magnetic suspension switched reluctance motor and a suspension force control device, method and system thereof. The magnetic suspension switched reluctance motor integrates the functions of the switched reluctance motor and the magnetic suspension bearing, realizes the natural decoupling of a torque winding and a suspension winding structurally, utilizes the torque winding to generate output torque, and utilizes the suspension winding to generate radial suspension force; the suspension force control device adopts a three-phase full-bridge inverter circuit to generate three-phase suspension winding current so as to control the suspension force of the magnetic suspension switched reluctance motor, the integration level is high, the control is simple, and the control hardware cost is saved; the suspension force control method determines duration of each conducting state according to the radial displacement of the rotor, a real-time current signal of the suspension winding and a preset reference displacement, so that the real-time current signal tracks an upper reference current value, and the rotor is stabilized at a reference position.

Description

Magnetic suspension switched reluctance motor and suspension force control device, method and system thereof

Technical Field

The invention relates to a magnetic suspension switched reluctance motor and a suspension force control device, method and system thereof, belonging to the technical field of magnetic suspension switched reluctance motors.

Background

The switched reluctance motor has a simple structure, the stator and the rotor are both in a salient pole structure, the stator is wound with a centralized winding, the rotor has no winding and no permanent magnet, and pulse current is excited to the stator winding at fixed time by detecting the real-time position of the rotor, so that the switched reluctance motor generates reluctance positive torque to drive the motor to run electrically. The high-speed performance is good, the fault-tolerant performance is strong, the high-temperature resistance and the grease resistance are high, the environmental suitability is strong, and the high-speed performance oil-resistant composite material is widely applied to the fields of aerospace, electric automobiles, flywheel energy storage, textile petroleum mines and the like.

The magnetic suspension bearing is produced by overcoming the defects of bearing friction, mechanical vibration and the like caused by the existence of a support bearing in the traditional motor, the magnetic suspension bearing detects the position of a rotor by using a position sensor, controls the current of a stator winding based on a power amplifier, suspends the rotor rotating at a high speed in the air, avoids mechanical contact with the high-speed motor, can effectively reduce the volume and weight of the device and improve the performance of equipment, and has good application prospect in high-power occasions such as a distributed power generation system, an uninterrupted power supply, a micro engine, a high-speed lathe spindle, an electric/hybrid electric vehicle and a multi-electric full-electric aircraft.

If the bearingless switched reluctance motor integrates two functions of rotation and suspension, the problems of loss, heating and the like caused by bearing friction during high-speed operation can be effectively solved, and the high-speed adaptability of the switched reluctance motor can be further exerted, so that the application basis of the switched reluctance motor in the high-speed fields of aerospace, flywheel energy storage, ships and warships and the like is strengthened. However, magnetic suspension switched reluctance motors with traditional structures, such as 12/8, 6/4, 8/6 and the like, have strong coupling relationship between torque and suspension force due to restriction of operation mechanism, and are difficult to completely solve the coupling of the torque and the suspension force in control, so that the motors with the structures have poor high-speed suspension performance and complicated and huge control circuits.

Accordingly, the present application provides a magnetic levitation switched reluctance motor and a levitation force control apparatus, method and system thereof.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a magnetic suspension switched reluctance motor and a suspension force control device, method and system thereof, so that a torque winding and a suspension winding are structurally decoupled, and the suspension force can be independently controlled.

In order to achieve the purpose, the invention is realized by adopting the following technical scheme:

in a first aspect, the invention provides a magnetic suspension switched reluctance motor, which comprises a plurality of torque coils, a plurality of suspension coils, a rotating shaft, a permanent magnet ring and two fixed rotation modules arranged in parallel;

each fixed-rotation module comprises a radial force stator, a torque stator, a non-magnetic-conduction support frame, a stator annular magnetic guide yoke, a rotor and a rotor annular magnetic guide yoke;

a permanent magnet ring is arranged between the stator annular magnetic yoke of the two fixed rotation modules;

the rotor annular magnetic guide yoke, the rotor, the radial force stator and the stator annular magnetic guide yoke are sequentially coaxially sleeved outside the rotating shaft from inside to outside;

the torque stator comprises a base II, and two convex teeth II which are arranged oppositely are arranged on the inner side of the base II;

the rotor comprises an annular base III, and 16 convex teeth III are arranged on the outer periphery of the annular base III at equal intervals;

the radial force stator comprises an annular base I, and 6 convex teeth I are arranged on the inner peripheral part of the annular base I at equal intervals;

a non-magnetic-conduction support frame is coaxially embedded between every two adjacent convex teeth I, one side of the non-magnetic-conduction support frame is connected with the annular base I, and the other side of the non-magnetic-conduction support frame is coaxially provided with a base II of the torque stator;

the torque coil and the suspension coil are wound in any one of the following four combinations D1+ D3, D2+ D3, D1+ D4 and D2+ D4:

d1: a torque coil is wound on each parallel convex tooth II in the torque stators which are positioned in the same radial direction of the two fixed-rotation modules in parallel, the two torque coils of each parallel torque stator are connected in series to obtain a torque coil string, the axially symmetric torque coil strings are connected in series two by two to form torque windings, and an armature-integrated three-phase torque winding is obtained;

d2: each convex tooth II is independently wound with a torque coil, two torque coils of each torque stator are connected in series to obtain a torque coil string, and torque coil strings which are axially symmetrical in each fixed-rotation module are connected in series in pairs to form torque windings to obtain three-phase torque windings of an armature split body;

d3: each convex tooth I is independently wound with a suspension coil, the suspension coils on the convex teeth I which are parallel in the same radial direction of the two fixed rotating modules are respectively connected in series to obtain suspension coil strings, the axially symmetric suspension coil strings are connected in series two by two to form suspension windings, and three-phase suspension windings with two degrees of freedom are obtained;

d4: and each convex tooth I is independently wound with a suspension coil, and every two suspension coils with axisymmetric axes of each fixed-rotation module are connected in series to form a suspension winding, so that a four-degree-of-freedom three-phase suspension winding is obtained.

Further, the permanent magnet ring is of an annular structure.

Furthermore, the permanent magnet ring adopts an axial magnetizing mode to magnetize.

Further, the pole arc angle of each tooth i is 22.5 °.

Furthermore, the non-magnetic-conductive support frame is arranged in an arc shape.

In a second aspect, the invention provides a suspension force control device of a magnetic suspension switched reluctance motor, comprising a control unit, a clark conversion unit, a proportional-integral controller, a displacement detection sensor and a current sensor;

the displacement detection sensor detects the radial displacement of the rotor, the output end of the displacement detection sensor is connected with the proportional-integral controller, and the output end of the proportional-integral controller is connected with the control unit;

the current sensor outputs a real-time current signal for detecting the suspension winding, the output end of the current sensor is connected with the clark conversion unit, and the output end of the clark conversion unit is connected with the control unit;

the setting mode of the output end of the control unit comprises any one of the following E and F:

e: the output end of the connection control unit is provided with a three-phase full-bridge inverter circuit, the three-phase full-bridge inverter circuit comprises three bridge arms, each bridge arm comprises an upper switch tube and a lower switch tube which are conducted in a complementary mode, and each switch tube is coupled to the radial force stator;

f: the output end of the connection control unit is provided with two paths of three-phase full-bridge inverter circuits which are connected in parallel, each path of three-phase full-bridge inverter circuit comprises three bridge arms, each bridge arm comprises an upper switch tube and a lower switch tube which are in complementary conduction, each switch tube in one path of three-phase full-bridge inverter circuit is coupled to a radial force stator of one rotation-fixing module, and each switch tube in the other path of three-phase full-bridge inverter circuit is coupled to a radial force stator of the other rotation-fixing module.

Furthermore, an output end of the control unit is provided with an asymmetric bridge driving circuit, and the asymmetric bridge driving circuit is coupled to the torque stator.

Furthermore, two paths of asymmetrical bridge driving circuits connected in parallel are arranged at the output end of the connection control unit, wherein one path of asymmetrical bridge driving circuit is coupled to the torque stator of one fixed rotation module, and the other path of asymmetrical bridge driving circuit is coupled to the torque stator of the other fixed rotation module.

In a third aspect, the present invention provides a method for controlling a levitation force of a magnetic levitation switched reluctance motor, comprising the steps of:

and circularly iterating the following steps until the difference value between the radial displacement amount of the rotor in the X axis and the radial displacement amount of the rotor in the Y axis and the preset reference displacement is as follows:

acquiring radial displacement of an X axis and a Y axis of a rotor;

acquiring real-time current signals of an X axis and a Y axis of a suspension winding;

calculating a current reference value and a current error value by using the obtained radial displacement, the real-time current signal and a preset reference displacement;

calculating a sector discrimination coordinate by using the real-time current signal, the current reference value and the current error value, and mapping the sector discrimination coordinate into a preset vector sector;

determining the conducting state and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit according to the position of the sector distinguishing coordinate in the vector sector;

and adjusting the duration of each conducting state according to the conducting state and each conducting state sequence of the switching tube of each bridge arm in the three-phase full-bridge inverter circuit so as to control the suspension force of the magnetic suspension switched reluctance motor and keep the rotor on the reference displacement.

Further, the calculating the current error value by using the obtained radial displacement, the real-time current signal and the preset reference displacement includes:

calculating the difference value between the radial displacement and the reference displacement to obtain a displacement signal difference;

and calculating a current reference value by using the displacement signal difference, and calculating a difference value between the real-time current signal and the current reference value by using the current reference value to obtain a current error value.

Further, the sector identification coordinate (Δ i) is calculated by using the real-time current signal, the current reference value and the current error value _x ',△i _y ') includes the formula:

wherein R is the resistance value of the three-phase suspension winding, L is the inductance value of the three-phase suspension winding, and T _s Is the duration of one control cycle, i _xref As a reference value of the current of the X-axis of the levitation winding, i _yref Current reference value, i, for the Y axis of the levitation winding _x For real-time current signals of the X-axis of the levitation winding, i _y For suspending winding Y-axisOf the real-time current signal,. DELTA.i _x For the current error value of the X-axis of the levitation winding,. DELTA.i _y The current error value of the Y axis of the suspension winding is obtained.

Further, the vector sectors include six sectors sequentially arranged in the first phase to the fourth phase of the xoy coordinate, and the central angle of each sector is 60 degrees;

the X axis is superposed with the central line of the A-phase suspension winding, and the Y axis is superposed with the central line of the BC-phase suspension winding.

Further, the determining the conduction states and the conduction state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit according to the position of the sector distinguishing coordinate in the vector sector comprises:

when the sector distinguishing coordinate is in the first sector of the vector sector, the conducting states and the conducting states of the switching tubes of the bridge arms in the three-phase full-bridge inverter circuit are sequentially as follows: v ₀ →V ₄ →V ₆ →V ₇ →V ₆ →V ₄ →V ₀ ；

When the sector judgment coordinate is in the second sector of the vector sector, the conducting states and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₂ →V ₆ →V ₇ →V ₆ →V ₂ →V ₀ ；

When the sector discrimination coordinate is in the third sector of the vector sector, the conducting states and the conducting state sequence of the switching tubes of the bridge arms in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₂ →V ₃ →V ₇ →V ₃ →V ₂ →V ₀ ；

When the sector judgment coordinate is in the fourth sector of the vector sector, the conducting states and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₁ →V ₃ →V ₇ →V ₃ →V ₁ →V ₀ ；

When the sector judgment coordinate is in the fifth sector of the vector sector, the conducting state and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuitSequentially comprises the following steps: v ₀ →V ₁ →V ₅ →V ₇ →V ₅ →V ₁ →V ₀ ；

When the sector judgment coordinate is in the sixth sector of the vector sector, the conducting states and the conducting state sequences of the switching tubes of the bridge arms in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₄ →V ₅ →V ₇ →V ₅ →V ₄ →V ₀ ；

Wherein, V ₀ The switching tubes of the lower bridge arms of all bridge arms of ABC phases are conducted, V ₁ The switching tubes of the lower bridge arms of the AB phase are conducted, the switching tubes of the upper bridge arms of the C phase are conducted, and V is ₂ The switching tubes of the lower bridge arms of the AC phase are conducted, the switching tubes of the upper bridge arms of the B phase are conducted, and V is ₃ The switching tubes of the lower bridge arm of the A phase are conducted, the switching tubes of the upper bridge arm of the BC phase are conducted, and V is ₄ The switching tubes of the upper bridge arm of the phase A are conducted, the switching tubes of the lower bridge arm of the phase BC are conducted, and the switching tubes of the lower bridge arm of the phase B are V ₅ The switching tubes of the upper bridge arm and the lower bridge arm of the phase B are conducted, and V is ₆ The switching tubes of the upper bridge arms of the AB phase are conducted, the switching tubes of the lower bridge arms of the C phase are conducted, and the V phase is ₇ The bridge arms of ABC phases are all connected with the bridge arm switch tubes.

Further, the adjusting the duration of each conducting state according to the conducting state and the sequence of each conducting state of the switching tube of each bridge arm in the three-phase full-bridge inverter circuit comprises

If the conduction states of the switching tubes of the bridge arms and the sequence of the conduction states are as follows: v ₀ →V ₄ →V ₆ →V ₇ →V ₆ →V ₄ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₄ -T ₆ )/2

in the formula,. DELTA.i _x ' and Δ i _y ' are all time length parameters, U _dc The method comprises the steps that the bus voltage of a suspension force control device is obtained, T is the duration of a V conduction state, T is the duration of the V conduction state, and T is the duration of the V conduction state;

if the conduction states of the switching tubes of the bridge arms and the sequence of the conduction states are as follows: v ₀ →V ₂ →V ₆ →V ₇ →V ₆ →V ₂ →V ₀ Then the duration of each on state is adjusted according to the following equation:

T ₀ ＝T ₇ ＝(T _s -T ₂ -T ₆ )/2

in the formula, T is the duration of the V conduction state;

if the conduction states of the switching tubes of the bridge arms and the sequence of the conduction states are as follows: v ₀ →V ₂ →V ₃ →V ₇ →V ₃ →V ₂ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₂ -T ₃ )/2

in the formula, T is the duration of the V conduction state;

if the conduction states of the switching tubes of the bridge arms and the sequence of the conduction states are as follows: v ₀ →V ₁ →V ₃ →V ₇ →V ₃ →V ₁ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₁ -T ₃ )/2

in the formula, T is the duration of the V conduction state;

if the conduction states of the switching tubes of the bridge arms and the sequence of the conduction states are as follows: v ₀ →V ₁ →V ₅ →V ₇ →V ₅ →V ₁ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₁ -T ₅ )/2

in the formula, T is the duration of the V conduction state;

if the conduction states of the switching tubes of the bridge arms and the sequence of the conduction states are as follows: v ₀ →V ₄ →V ₅ →V ₇ →V ₅ →V ₄ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₄ -T ₅ )/2。

further, the adjusting the duration of each conducting state according to the conducting state of the switching tube of each bridge arm in the three-phase full-bridge inverter circuit and the sequence of each conducting state includes:

judging the relation between the duration of each conduction state and the duration of the control period:

wherein, when T ₄ +T ₆ >T _s When T and T are updated by:

when T is ₂ +T ₆ >T _s When T and T are updated by:

when T is ₂ +T ₃ >T _s Then, T and T are updated by:

when T is ₁ +T ₃ >T _s Then, T and T are updated by:

when T is ₁ +T ₅ >T _s Then, T and T are updated by:

when T is ₄ +T ₅ >T _s Then, T and T are updated by:

in a fourth aspect, the present invention provides a levitation force control system for a magnetic levitation switched reluctance motor, comprising:

the radial displacement module is used for acquiring the radial displacement of the X axis and the Y axis of the rotor;

the real-time current signal module is used for acquiring real-time current signals of an X axis and a Y axis of the suspension winding;

the calculation module is used for calculating a current reference value and a current error value by using the obtained radial displacement, the real-time current signal and a preset reference displacement;

the vector mapping module is used for calculating a sector discrimination coordinate by utilizing the real-time current signal, the current reference value and the current error value and mapping the sector discrimination coordinate into a preset vector sector;

the conducting state determining module is used for determining the conducting state and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit according to the position of the sector distinguishing coordinate in the vector sector;

and the duration control module is used for adjusting the duration of each conducting state according to the conducting state and each conducting state sequence of the switching tube of each bridge arm in the three-phase full-bridge inverter circuit, and is used for controlling the suspension force of the magnetic suspension switched reluctance motor so as to keep the rotor on the reference displacement.

Compared with the prior art, the invention has the following beneficial effects:

the motor integrates the functions of a switched reluctance motor and a magnetic suspension bearing, realizes the natural decoupling of a torque winding and a suspension winding structurally, generates output torque by using the torque winding, and generates radial suspension force by using the suspension winding; the torque windings and the suspension windings of all phases are isolated from each other, so that the fault-tolerant performance is good, and the iron core loss is small; the three-phase full-bridge inverter circuit is adopted to generate three-phase suspension winding current so as to control the suspension force of the magnetic suspension switched reluctance motor, the integration level is high, the control is simple, and the control hardware cost is saved; according to the invention, the duration of each conducting state is determined according to the radial displacement of the rotor, the real-time current signal of the suspension winding and the preset reference displacement, so that the real-time current signal tracks the upper reference current value, and the rotor is stabilized at the reference position.

Drawings

Fig. 1 is a schematic structural diagram of an armature split type four-degree-of-freedom magnetic suspension switched reluctance motor according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an armature-integrated magnetic suspension switched reluctance motor according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram illustrating an embodiment of the present invention in which the center lines of two adjacent teeth III coincide with the center line of the torque stator;

FIG. 4 is a schematic view of an embodiment of the present invention in which the tooth centerline of tooth III coincides with the centerline of the torque stator;

fig. 5 is a schematic view of a closed loop of an embodiment of the bias flux generated by the permanent magnet ring of the present invention;

FIG. 6 is a schematic diagram of a closed loop of an embodiment of the radial two-pole symmetric magnetic flux generated by the levitation winding of a fixed rotation module according to the present invention;

FIG. 7 is a schematic diagram of a closed loop of an embodiment of a radially two-pole symmetric magnetic flux generated by a levitation winding of another fixed-rotation module according to the present invention;

fig. 8 is a schematic structural diagram of an embodiment of a levitation force control device of a magnetic levitation switched reluctance motor of the present invention;

FIG. 9 is a circuit diagram of a three-phase full-bridge inverter of the present invention;

FIG. 10 is a block diagram of one embodiment of a vector sector of the present invention;

FIG. 11 is a graph showing simulated waveforms of the real-time current signal and the current reference value according to the present invention;

in the figure: 1. a radial force stator 3, a torque stator 4, a non-magnetic-conductive support frame 5, a torque coil 6, a suspension coil 8, a permanent magnet ring 9, a stator annular magnetic guide yoke 11, the rotor 12, the rotor annular magnetic conducting yoke 13, the rotating

shaft

16 and 20 are bias magnetic fluxes generated by the permanent magnetic ring in two fixed rotating modules respectively, 17 and 21 are radial two-pole symmetric magnetic fluxes generated by two fixed rotating module A-phase suspension winding currents respectively, 18 and 22 are radial two-pole symmetric magnetic fluxes generated by two fixed rotating module B-phase suspension winding currents respectively, 19 and 23 are radial two-pole symmetric magnetic fluxes generated by two fixed rotating module C-phase suspension winding currents respectively, 27 and an X-axis current reference value simulation waveform, 28 and an X-axis real-time current signal simulation waveform, 29 and a Y-axis current reference value simulation waveform, 30 and a Y-axis real-time current signal simulation waveform, i. _a + is the current flowing in the A-phase torque winding, i _a The current flowing out of the A-phase torque winding, i _A +、i _B +、i _C + is the current i flowing in the A, B and C phase suspension winding _A -、i _B -、i _C The currents flowing out of the A, B and C phase levitation windings, i _x ^* And i _y ^* X-axis and Y-axis reference current values, respectively.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

Example 1:

the embodiment provides an armature split type four-degree-of-freedom magnetic suspension switched reluctance motor.

The magnetic suspension switched reluctance motor of the embodiment comprises a plurality of torque coils 5, a plurality of suspension coils 6, a rotating shaft 13, a permanent magnet ring 8 and two rotating and fixing modules which are arranged in parallel. Wherein, two decide the rotational mode group and closely overlap and establish on pivot 13 side by side, and the technical staff in the art can set up pivot 13 length according to actual demand. In addition, each stator-rotor module comprises a radial force stator 1, a torque stator 3, a non-magnetic-conductive support frame 4, a stator annular magnetic yoke 9, a rotor 11 and a rotor annular magnetic yoke 12.

In application, the permanent magnet ring 8 is magnetized in an axial magnetizing mode, the permanent magnet ring 8 is arranged between the two fixed rotating modules, one side of the permanent magnet ring is connected with the stator annular magnetic yoke 9 of one fixed rotating module, and the other side of the permanent magnet ring is connected with the stator annular magnetic yoke 9 of the other fixed rotating module.

Referring to fig. 1, a rotor annular magnetic guiding yoke 12, a rotor 11, a radial force stator 1, and a stator annular magnetic guiding yoke 9 are coaxially sleeved outside a rotating shaft 13 from inside to outside in sequence, wherein the rotor annular magnetic guiding yoke 12 is rotatably connected with the rotating shaft 13.

Referring to fig. 1, the torque stator 3 includes a base ii with an arc structure, and two opposite convex teeth ii are arranged on the inner side of the base ii; the rotor 11 comprises an annular base III with an annular structure, 16 convex teeth III are arranged on the outer periphery of the annular base III at equal intervals, and the central angle between every two adjacent convex teeth III is 22.5 degrees; radial force stator 1 includes annular base I of loop configuration, and the inner peripheral portion equidistance of annular base I is equipped with 6 dogtooth I, and dogtooth I sets up with dogtooth III is relative, and the pole arc angle of each dogtooth I is 22.5, and the central angle between the adjacent dogtooth I is 60.

In application, a non-magnetic-conduction support frame 4 with an arc-shaped structure is coaxially embedded between every two adjacent convex teeth I, one side of the non-magnetic-conduction support frame is connected with the annular base I, the other side of the non-magnetic-conduction support frame is coaxially provided with a base II of the torque stator 3, and the convex teeth II of the torque stator 3 are arranged opposite to the convex teeth III. Namely, the central line of the torque stator 3 and the central line of the non-magnetic-conduction support frame 4 are superposed with the central lines of the two convex teeth II of the corresponding torque stator, and the number of the non-magnetic-conduction support frame 4 and the number of the torque stators 3 are both 6.

The torque winding and the suspension winding of the magnetic suspension switched reluctance motor are mutually independent in wiring. Referring to fig. 1, a torque coil 5 is independently wound on each tooth ii in each torque stator 3 of two fixed rotation modules, and two torque coils 5 of each torque stator 3 are connected in series to obtain a torque coil string, and the torque coil strings symmetrically arranged on the central axis of each fixed rotation module are connected in series two by two to form a torque winding, that is, two torque coil strings with a space difference of 180 ° are connected in series two by two to obtain a three-phase torque winding of an armature split type. In addition, each convex tooth I is independently wound with a suspension coil 6, every two suspension coils 6 symmetrically arranged on the central axis of each fixed-rotation module are connected in series to form suspension windings, namely every two suspension coils with a space difference of 180 degrees are connected in series to obtain a four-degree-of-freedom three-phase suspension winding.

The motor integrates the functions of a switched reluctance motor and a magnetic suspension bearing, realizes the natural decoupling of a torque winding and a suspension winding structurally, generates output torque by using the torque winding, and generates radial suspension force by using the suspension winding; the invention has the advantages that each phase torque winding and each phase suspension winding are mutually isolated, the fault tolerance performance is good, and the iron core loss is small.

Example 2:

the embodiment provides an armature integrated two-degree-of-freedom magnetic suspension switched reluctance motor.

The difference between this embodiment and embodiment 1 lies in the arrangement of the torque coil and the levitation coil, which is as follows:

referring to fig. 2, a torque coil 5 is wound on each parallel convex tooth ii of the two parallel torque stators in the same radial direction of the two fixed-rotation modules, the two torque coils 5 of each parallel torque stator 3 are connected in series to obtain a torque coil string, and the axially symmetrically arranged torque coil strings are connected in series two by two to form torque windings, that is, the torque coil strings with a space difference of 180 ° are connected in series two by two to obtain a armature-integrated three-phase torque winding.

In addition, each convex tooth I is independently wound with a suspension coil 6, the suspension coils on the convex teeth I which are parallel in the two fixed rotation modules are connected in series to obtain suspension coil strings, the suspension coil strings which are arranged in axial symmetry are connected in series in pairs to form suspension windings, namely the suspension coil strings with the space difference of 180 degrees are connected in series in pairs to obtain the three-phase suspension winding with two degrees of freedom.

Example 3:

the embodiment provides an armature split type two-degree-of-freedom magnetic suspension switched reluctance motor.

The present embodiment is different from embodiment 1 in the arrangement of the levitation coil, which is specifically as follows:

each convex tooth I is independently wound with a suspension coil 6, the suspension coils of the convex teeth I which are positioned in parallel in the same radial direction of the two fixed rotating modules are respectively connected in series to obtain suspension coil strings, the suspension coil strings which are arranged in axial symmetry are connected in series two by two to form suspension windings, namely, the suspension coil strings which are 180 degrees apart in space are connected in series two by two to obtain a three-phase suspension winding with two degrees of freedom.

The armature split type two-degree-of-freedom magnetic suspension switched reluctance motor is obtained in the embodiment.

Example 4:

the embodiment provides an armature integrated four-degree-of-freedom magnetic suspension switched reluctance motor.

The present embodiment is different from embodiment 2 in the arrangement of the levitation coil, which is specifically as follows:

each convex tooth I is independently wound with a suspension coil 6, every two suspension coils 6 symmetrically arranged on the axis of each fixed rotating module are connected in series to form a suspension winding, namely every two suspension coils with a space difference of 180 degrees are connected in series to obtain a four-degree-of-freedom three-phase suspension winding.

The torque winding and the suspension winding of the magnetic suspension switched reluctance motor are mutually independent in wiring.

In this embodiment, when a current is applied to a one-phase torque winding, a two-pole symmetric magnetic flux is generated.

The magnetic flux is distributed in NS at two convex teeth II of a torque stator 3, and the magnetic flux closed loop is as follows: one convex tooth II, a radial air gap, a convex tooth III or a convex tooth III of the torque stator, a rotor annular magnetic guide yoke, the radial air gap, the other convex tooth II of the torque stator, a base II and one convex tooth II of the torque stator.

Referring to fig. 3, when the center line of two adjacent convex teeth iii coincides with the center line of the torque stator, the aligned position is formed, and the reluctance of the closed magnetic flux loop is the minimum; referring to fig. 4, the teeth centerline of tooth iii is out of alignment with the torque stator centerline where the reluctance of the closed flux loop is greatest.

In practical application, a single-polarity current is applied to a torque winding of one phase, the current of the torque winding generates a magnetic flux, the magnetic resistance of a magnetic flux closed loop always tends to be minimum in magnetic resistance, and a magnetic resistance electromagnetic torque is generated to enable a rotor to rotate from a non-aligned position to an aligned position of a stator and a rotor of the phase. Referring to fig. 4, when the a-phase torque winding is in a "non-aligned" position with the rotor for the stator and rotor poles, current is applied to the a-phase torque winding to generate an output torque to rotate the rotor to the "aligned" position for the stator and rotor poles, referring to fig. 3. And then, conducting a next-phase torque winding, rotating the position of the torque winding and the rotor from the position of the stator and rotor poles which are not aligned to the position of the stator and rotor poles which are aligned, and conducting A, B, C three-phase torque windings in turn to generate output torque to realize the rotating operation of the motor.

In the embodiment, the permanent magnet ring is magnetized in an axial magnetizing mode, and the permanent magnet ring generates bias magnetic flux.

Referring to fig. 5, the bias flux closed loop is: the permanent magnet ring is firstly connected with a stator annular magnetic yoke, a radial force stator, a radial air gap, a rotor and a rotor annular magnetic yoke of one stator-rotor module, then connected with a rotating shaft, then connected with a rotor annular magnetic yoke, a rotor, a radial air gap, a radial force stator and a stator annular magnetic yoke of another stator-rotor module, and finally returned to the permanent magnet ring.

In the embodiment, current is applied to one phase of the suspension winding, and the current of the suspension winding generates radial two-pole symmetric magnetic flux.

In application, the positive horizontal direction is a zero-degree spatial angle position, the spatial angle is positive when the anticlockwise direction changes, the X axis is specified to be parallel to the horizontal direction, the X axis is superposed with the central line of the A-phase suspension winding, and the Y axis is superposed with the central line of the BC-phase suspension winding.

Applying a current i with a current direction of 0-180 DEG to an A-phase suspension winding of a fixed rotation module _A When in use, the generated closed loop of the radial two-pole symmetric magnetic flux is as follows: the fixed rotation moduleThe rotor is characterized by comprising a convex tooth I at the position of 0 degree, a radial air gap, a convex tooth III at the position of 0 degree, a rotor annular magnetic guide yoke, a convex tooth III at the position of 180 degrees, a radial air gap, a convex tooth I at the position of 180 degrees, a stator annular magnetic guide yoke and a convex tooth I at the position of 0 degree. Referring to fig. 6, a current i is applied to the a-phase suspension winding of the fixed rotation module _A When the suspension force is generated, the air gap magnetic flux at the position of 0 degree is enhanced, the air gap magnetic flux at the position of 180 degrees is weakened, and the suspension force pointing to the position angle direction of 0 degree is generated; applying current-i to the A-phase suspension winding of the fixed rotation module _A When the suspension is in use, a reverse suspension force pointing to the 180-degree position angle direction is generated.

Applying a current-i with the current direction of 180-0 degrees to the A-phase suspension winding of the other fixed rotation module _A When in use, the generated closed loop of the radial two-pole symmetric magnetic flux is as follows: the stator module comprises a convex tooth I at a 180-degree position, a radial air gap, a convex tooth III at a 180-degree position, a rotor annular magnetic guide yoke, a convex tooth III at a 0-degree position, a radial air gap, a convex tooth I at a 0-degree position, a stator annular magnetic guide yoke and a convex tooth I at a 180-degree position. Referring to fig. 7, a current-i is applied to the a-phase levitation winding of the stator module _A When the suspension force is generated, the air gap magnetic flux at the position of 0 degree is enhanced, the air gap magnetic flux at the position of 180 degrees is weakened, and the suspension force pointing to the angle direction of 0 degree is generated; applying current i to the A-phase suspension winding of the fixed rotation module _A When the suspension is in use, a reverse suspension force pointing to the 180-degree position angle direction is generated.

Applying a current i with a current direction of 120-300 degrees to a B-phase suspension winding of a fixed rotation module _B When in use, the generated radial dipolar flux has a closed loop as follows: the stator module comprises a convex tooth I at a 120-degree position, a radial air gap, a convex tooth III at a 120-degree position, a rotor annular magnetic guide yoke, a convex tooth III at a 300-degree position, a radial air gap, a convex tooth I at a 300-degree position, a stator annular magnetic guide yoke and a convex tooth I at a 120-degree position. Referring to fig. 6, a current i is applied to the B-phase levitation winding of the stator module _B When the suspension force is generated, the air gap magnetic flux at the position of 120 degrees is enhanced, the air gap magnetic flux at the position of 300 degrees is weakened, and the suspension force pointing to the angle direction of 120 degrees is generated; applying current-i to the B-phase suspension winding of the fixed rotation module _B When the suspension is in the direction of the 300-degree position angle, a reverse suspension force is generated.

Applying a current-i with the current direction of 300-120 degrees to a B-phase suspension winding of another fixed rotation module _B When in use, the generated closed loop of the radial two-pole symmetric magnetic flux is as follows: the stator module comprises a convex tooth I at a 300-degree position, a radial air gap, a convex tooth III at a 300-degree position, a rotor annular magnetic guide yoke, a convex tooth III at a 120-degree position, a radial air gap, a convex tooth I at a 120-degree position, a stator annular magnetic guide yoke and a convex tooth I at a 300-degree position. Referring to fig. 7, a current-i is applied to the B-phase levitation winding of the stator module _B When the suspension force is generated, the air gap magnetic flux at the position of 120 degrees is enhanced, and the air gap magnetic flux at the position of 300 degrees is weakened, so that the suspension force pointing to the position angle of 120 degrees is generated; applying current i to the B-phase suspension winding of the fixed rotation module _B When the suspension is in the direction of the 300-degree position angle, a reverse suspension force is generated.

Applying a current i with a current direction of 60-240 degrees to a C-phase suspension winding of a fixed rotation module _C When in use, the generated closed loop of the radial two-pole symmetric magnetic flux is as follows: the stator module comprises a convex tooth I at a 60-degree position, a radial air gap, a convex tooth III at a 60-degree position, a rotor annular magnetic guide yoke, a convex tooth III at a 240-degree position, a radial air gap, a convex tooth I at a 240-degree position, a stator annular magnetic guide yoke and a convex tooth I at a 60-degree position. Referring to fig. 6, a current i is applied to the C-phase levitation winding of the stator module _C When the magnetic field is applied, the air gap magnetic flux at the position of 60 degrees is enhanced, the air gap magnetic flux at the position of 240 degrees is weakened, and a levitation force pointing to the position angle direction of 60 degrees is generated; applying current-i to the C-phase suspension winding of the fixed rotation module _C When the suspension is in the direction of 240 degrees, a reverse suspension force is generated.

Applying current-i with the current direction of 240-60 degrees to the C-phase suspension winding of the other fixed rotation module _C When in use, the generated closed loop of the radial two-pole symmetric magnetic flux is as follows: the stator module comprises a convex tooth I at a 240-degree position, a radial air gap, a convex tooth III at a 240-degree position, a rotor annular magnetic guide yoke, a convex tooth III at a 60-degree position, a radial air gap, a convex tooth I at a 60-degree position, a stator annular magnetic guide yoke and 240Teeth I at the degree position. Referring to fig. 7, a current-i is applied to the C-phase levitation winding of the stator module _C When the magnetic field is applied, the air gap magnetic flux at the position of 60 degrees is enhanced, the air gap magnetic flux at the position of 240 degrees is weakened, and a levitation force pointing to the position angle direction of 60 degrees is generated; applying current i to the C-phase suspension winding of the fixed rotation module _C When the suspension is in the direction of 240 degrees, a reverse suspension force is generated.

Example 5:

the embodiment provides a suspension force control device of a magnetic suspension switched reluctance motor.

The suspension force control device of the magnetic suspension switched reluctance motor comprises a control unit, a clark conversion unit, a proportional-integral controller, a displacement detection sensor and a current sensor.

Referring to fig. 8, the displacement detecting sensor is used for detecting the radial displacement of the rotor in the X axis and the Y axis, the output end of the displacement detecting sensor is connected to the proportional-integral controller, and the output end of the proportional-integral controller is connected to the control unit.

The current sensor is used for detecting real-time current signals of an X axis and a Y axis of the suspension winding, the output end of the current sensor is connected with the clark conversion unit, and the output end of the clark conversion unit is connected with the control unit.

In addition, the output end of the connection control unit is provided with a three-phase full-bridge inverter circuit, the three-phase full-bridge inverter circuit comprises three bridge arms, each bridge arm comprises an upper switch tube and a lower switch tube which are in complementary conduction, and each switch tube is coupled to the suspension winding of the radial force stator.

In application, the A, B, C three-phase suspension winding is coupled to a three-phase full-bridge inverter circuit by adopting a star connection method, namely, a phase suspension winding is coupled between an upper switch tube and a lower switch tube of each bridge arm.

The magnitude and the direction of three suspension forces can be controlled by reasonably controlling the magnitude and the direction of the current of each phase of the suspension winding, so that the suspension forces in three arbitrary directions and magnitudes are generated, and the stable suspension operation of the rotor with one radial two-degree-of-freedom is realized.

Example 6:

This example differs from example 5 in that: the output end of the connection control unit of the embodiment is provided with two three-phase full-bridge inverter circuits connected in parallel, each three-phase full-bridge inverter circuit comprises three bridge arms, each bridge arm comprises an upper switch tube and a lower switch tube which are in complementary conduction, each switch tube in one three-phase full-bridge inverter circuit is coupled to a suspension winding of a radial force stator of one fixed rotation module, and each switch tube in the other three-phase full-bridge inverter circuit is coupled to a suspension winding of a radial force stator of the other fixed rotation module.

The magnitude and the direction of three suspension forces can be controlled by reasonably controlling the magnitude and the direction of the current of each phase of the suspension winding, so that the suspension forces in three arbitrary directions and magnitudes are generated, and the stable suspension operation of the rotor with one radial four degrees of freedom is realized.

Example 7:

on the basis of

embodiment

5 or 6, the present embodiment provides a torque control device for a magnetic levitation switched reluctance motor.

The output end of the control unit of this embodiment is provided with an asymmetric bridge driving circuit, and the asymmetric bridge driving circuit is coupled to the torque stator 3.

Example 8:

on the basis of

embodiment

This example differs from example 8 in that: the output end of the control unit of this embodiment is provided with two parallel asymmetric bridge driving circuits, wherein one of the asymmetric bridge driving circuits is coupled to the torque stator 3 of one stator module, and the other is coupled to the torque stator 3 of the other stator module.

Example 9:

on the basis of

embodiment

5 or 6, this embodiment provides a levitation force control method for a magnetic levitation switched reluctance motor.

The suspension force control method of the magnetic suspension switched reluctance motor comprises the following steps:

and circularly iterating the following steps until the difference value between the radial displacement amount of the rotor X axis and the radial displacement amount of the rotor Y axis and the preset reference displacement is 0:

s1, acquiring radial displacement of the X axis and the Y axis of the rotor;

s2, acquiring real-time current signals of an X axis and a Y axis of the suspension winding;

s3, calculating a current reference value and a current error value by using the obtained radial displacement, the real-time current signal and a preset reference displacement;

s4, calculating sector distinguishing coordinates by using the real-time current signals, the current reference values and the current error values, and mapping the sector distinguishing coordinates into a preset vector sector;

s5, determining the conducting state and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit according to the position of the sector distinguishing coordinate in the vector sector;

s6, adjusting the duration of each conducting state according to the conducting state and the conducting state sequence of the switch tube of each bridge arm in the three-phase full-bridge inverter circuit, and controlling the suspension force of the magnetic suspension switched reluctance motor to keep the rotor on the reference displacement.

According to the invention, the duration of each conducting state is determined according to the radial displacement of the rotor, the real-time current signal of the suspension winding and the preset reference displacement, so that the real-time current signal tracks the upper reference current value, and the rotor is stabilized at the reference position.

Example 10:

the present embodiment introduces a suspension force control method for a radial two-degree-of-freedom magnetic suspension switched reluctance motor, and on the basis of embodiment 9, the present embodiment introduces a current error value calculation method, a sector discrimination coordinate calculation method, a method for determining conduction states of switching tubes of bridge arms and sequences of the conduction states, and a method for determining duration of the conduction states in detail.

(I) current error value

Calculating a current error value by using the obtained radial displacement, the real-time current signal and the preset reference displacement comprises:

Fig. 11 is a simulation waveform diagram of the real-time current signal and the current reference value according to the present embodiment. Wherein, the waveform of the current reference value of the X axis is preset as sine quantity of sin (80 pi X), and the sudden change occurs after 0.03 second; the waveform of the reference value of the Y-axis current is preset to a sine quantity of sin (80 pi x + pi/2), and a sudden change occurs after 0.02 seconds.

As can be seen from fig. 11, the X-axis real-time current signal and the Y-axis real-time current signal of the present embodiment have high tracking accuracy, small current ripple, and good tracking effect.

Sector (II) discrimination coordinates

Calculating sector discrimination coordinates (Δ i) using real-time current signals, current reference values and current error values _x ',△i _y ') includes the formula:

wherein R is the resistance value of the three-phase suspension winding, L is the inductance value of the three-phase suspension winding, and T _s Is the duration of one control cycle, i _xref As a reference value of the current of the X-axis of the levitation winding, i _yref Reference value of current for Y-axis of levitation winding, i _x For a real-time current signal of the X-axis of the levitation winding, i _y For real-time current signals, Δ i, of the Y-axis of the levitation winding _x For the current error value of the X-axis of the levitation winding,. DELTA.i _y The current error value of the Y axis of the suspension winding is obtained.

(III) conducting state of switching tube of each bridge arm and sequence of each conducting state

First, vector sectors are constructed, which include six sectors sequentially arranged in the first phase to the fourth phase of the xoy coordinate, and the central angle of each sector is 60 °, refer to fig. 10. The X axis is superposed with the central line of the A-phase suspension winding, and the Y axis is superposed with the central line of the BC-phase suspension winding.

Then, determining the conducting state and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit according to the position of the sector distinguishing coordinate in the vector sector, and specifically:

3.1 when the sector distinguishing coordinate is in the first sector of the vector sector, the conducting state and the conducting state sequence of the switching tube of each bridge arm in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₄ →V ₆ →V ₇ →V ₆ →V ₄ →V ₀ ；

3.2 when the sector distinguishing coordinate is in the second sector of the vector sector, the conducting states and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₂ →V ₆ →V ₇ →V ₆ →V ₂ →V ₀ ；

3.3 when the sector distinguishing coordinate is in the third sector of the vector sector, the conducting states and the conducting states of the switching tubes of the bridge arms in the three-phase full-bridge inverter circuit are sequentially as follows: v ₀ →V ₂ →V ₃ →V ₇ →V ₃ →V ₂ →V ₀ ；

3.4 when the sector distinguishing coordinate is in the fourth sector of the vector sector, the conducting states and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₁ →V ₃ →V ₇ →V ₃ →V ₁ →V ₀ ；

3.5 when the sector distinguishing coordinate is in the fifth sector of the vector sector, the conducting states and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₁ →V ₅ →V ₇ →V ₅ →V ₁ →V ₀ ；

3.6 when the sector identification coordinate is in the sixth sector of the vector sector, the conducting states and the conducting states of the switching tubes of the bridge arms in the three-phase full-bridge inverter circuit are sequentially as follows: v ₀ →V ₄ →V ₅ →V ₇ →V ₅ →V ₄ →V ₀ ；

Wherein, V ₀ The switching tubes of the lower bridge arms of all bridge arms of ABC phases are conducted, V ₁ The switching tubes of the lower bridge arms of the AB phase are conducted, the switching tubes of the upper bridge arms of the C phase are conducted, and V is ₂ The switching tubes of the lower bridge arms of the AC phase are conducted, the switching tubes of the upper bridge arms of the B phase are conducted, and V is ₃ The switching tubes of the lower bridge arm of the A phase are conducted, the switching tubes of the upper bridge arm of the BC phase are conducted, and V is ₄ The switching tubes of the upper bridge arm and the lower bridge arm of the BC phase are conducted, and V is ₅ The switching tubes of the upper bridge arm and the lower bridge arm of the phase B are conducted, and V is ₆ The switching tubes of the upper bridge arms of the AB phase are conducted, the switching tubes of the lower bridge arms of the C phase are conducted, and V is ₇ The bridge arms of ABC phases are all connected with the bridge arm switching tubes.

(IV) duration of each on-state

According to the conducting state and the conducting state sequence of the switching tube of each bridge arm in the three-phase full-bridge inverter circuit, the duration of each conducting state is adjusted, and the method specifically comprises the following steps:

4.1 if the conduction state and the conduction state sequence of the switching tube of each bridge arm are as follows: v ₀ →V ₄ →V ₆ →V ₇ →V ₆ →V ₄ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₄ -T ₆ )/2

in the formula,. DELTA.i _x ' and Δ i _y ' are all time length parameters, U _dc Bus voltage, T, for the levitation force control device ₀ Is a V ₀ Duration of the on-state, T ₄ Is a V ₄ Duration of the on-state, T ₆ Is a V ₆ Duration of the on-state, T ₇ Is a V ₇ The duration of the on state.

In application, the relationship between the duration of each conducting state and the duration of the control period is judged: when T is ₄ +T ₆ >T _s Then, T is updated by ₄ And T ₆ ：

4.2 if the conduction state and the conduction state sequence of the switching tube of each bridge arm are as follows: v ₀ →V ₂ →V ₆ →V ₇ →V ₆ →V ₂ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₂ -T ₆ )/2

in the formula, T ₂ Is a V ₂ The duration of the on state.

In application, the relationship between the duration of each conducting state and the duration of the control period is judged: when T is ₂ +T ₆ >T _s Then, T is updated by ₂ And T ₆ ：

4.3 if the conduction states and the conduction state sequences of the switching tubes of the bridge arms are as follows: v ₀ →V ₂ →V ₃ →V ₇ →V ₃ →V ₂ →V ₀ Then the duration of each on state is adjusted according to the following equation:

T ₀ ＝T ₇ ＝(T _s -T ₂ -T ₃ )/2

in the formula, T ₃ Is a V ₃ The duration of the on state.

In application, the relationship between the duration of each conducting state and the duration of the control period is judged: when T is ₂ +T ₃ >T _s Then, T is updated by ₂ And T ₃ ：

4.4 if the conduction state of the switching tube of each bridge arm and the sequence of the conduction states are as follows: v ₀ →V ₁ →V ₃ →V ₇ →V ₃ →V ₁ →V ₀ Then the duration of each conducting state is adjusted according to the following formula：

T ₀ ＝T ₇ ＝(T _s -T ₁ -T ₃ )/2

In the formula, T ₁ Is a V ₁ The duration of the on state.

In application, the relationship between the duration of each conducting state and the duration of the control period is judged: when T is ₁ +T ₃ >T _s Then, T is updated by ₁ And T ₃ ：

4.5 if the conduction states and the conduction state sequences of the switching tubes of the bridge arms are as follows: v ₀ →V ₁ →V ₅ →V ₇ →V ₅ →V ₁ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₁ -T ₅ )/2

in the formula, T ₅ Is a V ₅ The duration of the on state.

In application, the relationship between the duration of each conducting state and the duration of the control period is judged: when T is ₁ +T ₅ >T _s When the temperature of the water is higher than the set temperature,updating T by ₁ And T ₅ ：

4.6 if the conduction state and the conduction state sequence of the switching tube of each bridge arm are as follows: v ₀ →V ₄ →V ₅ →V ₇ →V ₅ →V ₄ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₄ -T ₅ )/2。

in application, the relationship between the duration of each conducting state and the duration of the control period is judged: when T is ₄ +T ₅ >T _s Then, T is updated by ₄ And T ₅ ：

In practical application, a phase suspension winding is coupled between the upper and lower switching tubes of each bridge arm in the three-phase full-bridge inverter circuit. Referring to FIG. 9, VD ₁ ～VD ₆ Are all switch tubes; l is _A 、L _B 、L _C Respectively, the inductance values of A, B, C three-phase levitation windings, and L _A ＝L _B ＝L _C ＝L；R _A 、R _B 、R _C Are respectively the resistance values of A, B, C three-phase suspension windings, and R _A ＝R _B ＝R _C ＝R。

Example 11:

on the basis of embodiment 10, this embodiment describes in detail the current variation value of each time segment of one control cycle.

Step 1: calculating theoretical change value of A-phase suspension winding current in one control period

Step 11: the a-phase levitation winding current is calculated by:

in the formula, i (t) is real-time current of the A-phase suspension winding, U is voltage at two ends of the A-phase suspension winding, and in application, the voltage at two ends of the A-phase is different under different conduction states of the switching tube.

Step 12: table 1 shows sector identification coordinates (Δ i) _x ',△i _y ') when the inverter is positioned in the first sector, the conduction state and the conduction state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit are realized, wherein 1 represents that the switching tubes on the bridge arms are conducted, and 0 represents that the switching tubes on the bridge arms are conducted; table 2 shows the voltages at the two ends of the floating winding of the corresponding phase in each conducting state, time t ₀ ～t ₁ When the on state of the switching tube is 000, U is 0, and t is calculated by the following equation _0～ t ₁ The A-phase suspension winding current change of the time segment is as follows:

in the formula, i (t) ₁ ) Is t ₁ Phase A levitation winding current, i (t) ₀ ) Is t ₀ A phase a suspension winding current, Δ ₁ Is t _0～ t ₁ The a-phase levitation winding current of the time segment changes.

TABLE 1 conducting state and sequence of the switching tubes of the bridge arms

TABLE 2 Voltage across the levitation winding for the corresponding phase in the on state

Step 13: calculating t by _1～ t ₂ The A-phase suspension winding current change of the time segment is as follows:

in the formula, i (t) ₂ ) Is t ₂ Phase a suspension winding current, Δ ₂ Is t _1～ t ₂ The a-phase levitation winding current of the time period changes. Step 14: calculating t by _2～ t ₃ The A-phase suspension winding current change of the time segment is as follows:

in the formula, i (t) ₃ ) Is t ₃ Phase a suspension winding current, Δ ₃ Is t _2～ t ₃ The a-phase levitation winding current of the time segment changes. Step 15: calculating t by _3～ t ₄ The A-phase suspension winding current change of the time segment is as follows:

in the formula, i (t) ₄ ) Is t ₄ Phase a suspension winding current, Δ ₄ Is t _3～ t ₄ A-phase suspension winding electricity of time periodThe flow changes. Step 16: calculating t by _4～ t ₅ The A-phase suspension winding current change of the time segment is as follows:

in the formula, i (t) ₅ ) Is t ₅ Phase a suspension winding current, Δ ₅ Is t _4～ t ₅ The a-phase levitation winding current of the time segment changes. And step 17: calculating t by _5～ t ₆ The A-phase suspension winding current change of the time segment is as follows:

in the formula, i (t) ₆ ) Is t ₆ Phase a suspension winding current, Δ ₆ Is t _5～ t ₆ The a-phase levitation winding current of the time segment changes. Step 18: calculating t by _6～ t ₇ The A-phase suspension winding current change of the time segment is as follows:

in the formula, i (t) ₇ ) Is t ₇ A phase a suspension winding current, Δ ₇ Is t _6～ t ₇ The a-phase levitation winding current of the time segment changes.

Step 19: calculating the current change of the A-phase suspension winding in one control period by the following formula:

in the formula, delta _A The A-phase suspension winding current changes for one control period.

In application, the time constant of the current inner loop is far less than that of the displacement outer loop, i (t) ₀ ),i(t ₁ ),i(t ₂ ),i(t ₃ ),i(t ₄ ),i(t ₅ ),i(t ₆ ) Approximately equal to the average value of the current over one switching period, i.e.:

wherein i _Aref (t ₀ )，i _A (t ₀ ) Reference value and actual value of phase A current at the starting time of the control period are respectively.

In practical application, the current change of the A-phase suspension winding in one control period is updated by the following formula:

step 2: calculating the theoretical change value of the B-phase suspension winding current in one control period by the following formula:

in the formula i _Bref (t ₀ )，i _B (t ₀ ) Respectively obtaining reference value and actual value for the phase B current at the starting time of the control period, delta _B The B-phase suspension winding current changes for one control period.

And step 3: calculating the theoretical change value of the C-phase suspension winding current in one control period by the following formula:

in the formula i _Cref (t ₀ )，i _C (t ₀ ) Respectively obtaining reference value and actual value for C phase current at the starting time of control period _C The current of the C-phase suspension winding changes for one control period.

And 4, step 4: three-phase current is normalized to two-phase current through a clark conversion formula, and theoretical change values of x-axis current and y-axis current in the control period are obtained, and the theoretical change values are as follows:

clark transformation:

in the formula, delta _x Is the change value of the x-axis current within a control period, delta _y Is the change value of the y-axis current in one control period.

In application, the calculated x-y axis theoretical current change value delta _x ，△ _y Respectively assigning current error values delta i at the starting moments of the control periods _x (t ₀ )，△i _y (t ₀ ) Namely: delta _x ＝i _xref (t ₀ )-i _x (t ₀ )＝△i _x (t ₀ )，△ _y ＝i _yref (t ₀ )-i _y (t ₀ )＝△i _y (t ₀ )。

When actually applied, i _x (t ₀ )＝i _x ，i _y (t ₀ )＝i _y ，i _xref (t ₀ )＝i _xref ，i _yref (t ₀ )＝i _yref ，△i _x (t ₀ )＝△i _x ，△i _y (t ₀ )＝△i _y 。

Example 12:

the embodiment provides a levitation force control system of a magnetic levitation switched reluctance motor, which comprises:

the vector mapping module is used for calculating sector judgment coordinates by utilizing the real-time current signals, the current reference values and the current error values and mapping the sector judgment coordinates into a preset vector sector;

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. The magnetic suspension switched reluctance motor is characterized by comprising a plurality of torque coils (5), a plurality of suspension coils (6), a rotating shaft (13), a permanent magnet ring (8) and two fixed rotation modules which are arranged in parallel;

each fixed-rotation module comprises a radial force stator (1), a torque stator (3), a non-magnetic-conduction support frame (4), a stator annular magnetic yoke (9), a rotor (11) and a rotor annular magnetic yoke (12);

a permanent magnet ring (8) is arranged between the stator annular magnetic yoke of the two fixed rotation modules;

the rotor annular magnetic guide yoke (12), the rotor (11), the radial force stator (1) and the stator annular magnetic guide yoke (9) are sequentially coaxially sleeved outside the rotating shaft (13) from inside to outside;

the torque stator (3) comprises a base II, and two convex teeth II which are arranged oppositely are arranged on the inner side of the base II;

the rotor (11) comprises an annular base III, and 16 convex teeth III are arranged on the outer peripheral part of the annular base III at equal intervals;

the radial force stator (1) comprises an annular base I, and 6 convex teeth I are arranged on the inner peripheral portion of the annular base I at equal intervals;

a non-magnetic-conductive support frame (4) is coaxially embedded between every two adjacent convex teeth I, one side of the non-magnetic-conductive support frame is connected with the annular base I, and the other side of the non-magnetic-conductive support frame is coaxially provided with a base II;

the torque coil (5) and the suspension coil (6) are wound in any one of the following four combinations D1+ D3, D2+ D3, D1+ D4 and D2+ D4:

d1: a torque coil (5) is wound on each parallel convex tooth II in the torque stators (3) which are positioned in parallel in the same radial direction of the two fixed rotation modules, the two torque coils (5) of each parallel torque stator (3) are connected in series to obtain a torque coil string, and the axially symmetrical torque coil strings are connected in series two by two to form a torque winding to obtain an armature-integrated three-phase torque winding;

d2: each convex tooth II is independently wound with a torque coil (5), two torque coils (5) of each torque stator (3) are connected in series to obtain a torque coil string, and the torque coil strings with axially symmetric center shafts of each fixed-rotating module are connected in series pairwise to form torque windings to obtain armature split three-phase torque windings;

d3: each convex tooth I is independently wound with a suspension coil (6), the suspension coils on the convex teeth I which are parallel in the same radial direction of the two fixed rotating modules are respectively connected in series to obtain suspension coil strings, the axially symmetric suspension coil strings are connected in series two by two to form suspension windings, and three-phase suspension windings with two degrees of freedom are obtained;

d4: each convex tooth I is independently wound with a suspension coil (6), and every two suspension coils (6) which are axially symmetrical in each fixed-rotation module are connected in series to form suspension windings, so that the four-degree-of-freedom three-phase suspension winding is obtained.

2. The magnetic levitation switched reluctance motor according to claim 1, wherein the permanent magnet ring (8) is of an annular structure.

3. The magnetic suspension switched reluctance motor according to claim 2, wherein the permanent magnet ring (8) is magnetized by axial magnetization.

4. The magnetic levitation switched reluctance motor as claimed in claim 1, wherein the pole arc angle of each tooth i is 22.5 °.

5. The magnetic levitation switched reluctance motor according to claim 1, wherein the non-magnetically conductive support frame (4) is arc-shaped.

6. The suspension force control device of the magnetic suspension switched reluctance motor is characterized by comprising a control unit, a clark conversion unit, a proportional-integral controller, a displacement detection sensor and a current sensor;

e: the output end of the connection control unit is provided with a three-phase full-bridge inverter circuit, the three-phase full-bridge inverter circuit comprises three bridge arms, each bridge arm comprises an upper switch tube and a lower switch tube which are conducted in a complementary mode, and each switch tube is coupled to the radial force stator (1);

f: the output end of the connection control unit is provided with two paths of three-phase full-bridge inverter circuits which are connected in parallel, each path of three-phase full-bridge inverter circuit comprises three bridge arms, each bridge arm comprises an upper switch tube and a lower switch tube which are in complementary conduction, each switch tube in one path of three-phase full-bridge inverter circuit is coupled to a radial force stator (1) of one fixed rotation module, and each switch tube in the other path of three-phase full-bridge inverter circuit is coupled to a radial force stator (1) of the other fixed rotation module.

7. The levitation force control device of the magnetic levitation switched reluctance motor as claimed in claim 6, wherein an asymmetric bridge driving circuit is provided at the output end of the control unit, and the asymmetric bridge driving circuit is coupled to the torque stator (3).

8. The levitation force control device of the magnetic levitation switched reluctance motor as claimed in claim 6, wherein two asymmetric bridge driving circuits connected in parallel are provided at the output end of the control unit, one of the asymmetric bridge driving circuits is coupled to the torque stator (3) of one stator module, and the other is coupled to the torque stator (3) of the other stator module.

9. The suspension force control method of the magnetic suspension switch reluctance motor is characterized by comprising the following steps of:

acquiring radial displacement of an X axis and a Y axis of a rotor;

calculating a sector judgment coordinate by using the real-time current signal, the current reference value and the current error value, and mapping the sector judgment coordinate into a preset vector sector;

determining the conducting state and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit according to the position of the sector distinguishing coordinates in the vector sector;

10. The levitation force control method of the magnetic levitation switched reluctance motor as claimed in claim 9, wherein the calculating the current error value using the obtained radial displacement amount, the real-time current signal and the preset reference displacement comprises:

11. The levitation force control method of the maglev switched reluctance motor as claimed in claim 9, wherein the sector identification coordinate (Δ i) is calculated using the real-time current signal, the current reference value and the current error value _x ',△i _y ') includes the formula:

wherein R is the resistance value of the three-phase suspension winding, L is the inductance value of the three-phase suspension winding, and T _s Is the duration of one control cycle, i _xref As a reference value of the current of the X-axis of the levitation winding, i _yref Current reference value, i, for the Y axis of the levitation winding _x For real-time current signals of the X-axis of the levitation winding, i _y For real-time current signals, Δ i, of the Y-axis of the levitation winding _x For the current error value of the X-axis of the levitation winding,. DELTA.i _y The current error value of the Y axis of the suspension winding is obtained.

12. The levitation force control method of magnetic levitation switched reluctance motor of claim 9, wherein the vector sector includes six sectors sequentially arranged at the xoy coordinates of the first phase to the fourth phase, each sector having a central angle of 60 °;

13. The levitation force control method of the magnetic levitation switched reluctance motor as claimed in claim 9, wherein the determining the conducting state and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit according to the position of the sector discrimination coordinate in the vector sector comprises:

when the sector discrimination coordinate is in the first sector of the vector sector, the conducting states and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit are as follows: v ₀ →V ₄ →V ₆ →V ₇ →V ₆ →V ₄ →V ₀ ；

When the sector judgment coordinate is in the fifth sector of the vector sector, the conducting state and the conducting state sequence of the switching tubes of each bridge arm in the three-phase full-bridge inverter circuit are in accordance withThe following steps are carried out: v ₀ →V ₁ →V ₅ →V ₇ →V ₅ →V ₁ →V ₀ ；

Wherein, V ₀ The switching tubes of the lower bridge arms of all bridge arms of ABC phases are conducted, V ₁ The switching tubes of the lower bridge arms of the AB phase are conducted, the switching tubes of the upper bridge arms of the C phase are conducted, and V is ₂ The switching tubes of the lower bridge arms of the AC phase are conducted, the switching tubes of the upper bridge arms of the B phase are conducted, and V is ₃ The switching tubes of the lower bridge arm of the A phase are conducted, the switching tubes of the upper bridge arm of the BC phase are conducted, and V is ₄ The switching tubes of the upper bridge arm and the lower bridge arm of the BC phase are conducted, and V is ₅ The switching tubes of the upper bridge arm and the lower bridge arm of the phase B are conducted, and V is ₆ The switching tubes of the upper bridge arms of the AB phase are conducted, the switching tubes of the lower bridge arms of the C phase are conducted, and the V phase is ₇ The bridge arms of ABC phases are all connected with the bridge arm switch tubes.

14. The levitation force control method of the magnetic levitation switched reluctance motor as claimed in claim 13, wherein the adjusting the duration of each conducting state according to the conducting state and each conducting state sequence of the switching tube of each bridge arm in the three-phase full-bridge inverter circuit comprises

T ₀ ＝T ₇ ＝(T _s -T ₄ -T ₆ )/2

in the formula,. DELTA.i _x ' and Δ i _y ' are all time length parameters, U _dc Bus voltage, T, for the levitation force control device ₀ Is a V ₀ Duration of the on-state, T ₄ Is a V ₄ Duration of the on-state, T ₆ Is a V ₆ Duration of the on-state, T ₇ Is a V ₇ Duration of the on state;

if the conduction states of the switching tubes of the bridge arms and the sequence of the conduction states are as follows: v ₀ →V ₂ →V ₆ →V ₇ →V ₆ →V ₂ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₂ -T ₆ )/2

in the formula, T ₂ Is a V ₂ The duration of the on state;

if the switch tube of each bridge arm is in conduction state and each bridge arm is in conductionThe state sequence is as follows: v ₀ →V ₂ →V ₃ →V ₇ →V ₃ →V ₂ →V ₀ Then, the duration of each conducting state is adjusted according to the following formula:

T ₀ ＝T ₇ ＝(T _s -T ₂ -T ₃ )/2

in the formula, T ₃ Is a V ₃ The duration of the on state;

T ₀ ＝T ₇ ＝(T _s -T ₁ -T ₃ )/2

in the formula, T ₁ Is a V ₁ The duration of the on state;

T ₀ ＝T ₇ ＝(T _s -T ₁ -T ₅ )/2

in the formula, T ₅ Is a V ₅ The duration of the on state;

T ₀ ＝T ₇ ＝(T _s -T ₄ -T ₅ )/2。

15. the levitation force control method of the magnetic levitation switched reluctance motor as claimed in claim 14, wherein the adjusting the duration of each conducting state according to the conducting state of the switching tube of each bridge arm in the three-phase full-bridge inverter circuit and the sequence of each conducting state comprises:

judging the relationship between the duration of each conducting state and the duration of the control period:

wherein, when T ₄ +T ₆ >T _s Then, T is updated by ₄ And T ₆ ：

When T is ₂ +T ₆ >T _s Then, T is updated by ₂ And T ₆ ：

When T is ₂ +T ₃ >T _s Then, T is updated by ₂ And T ₃ ：

When T is ₁ +T ₃ >T _s Then, T is updated by ₁ And T ₃ ：

When T is ₁ +T ₅ >T _s Then, T is updated by ₁ And T ₅ ：

When T is ₄ +T ₅ >T _s Then, T is updated by ₄ And T ₅ ：

16. Suspension force control system of magnetic suspension switch reluctance motor, its characterized in that includes: