CN109713958A - Three-level formula started with no brush/generator three-phase AC excitation system and control method - Google Patents
Three-level formula started with no brush/generator three-phase AC excitation system and control method Download PDFInfo
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Abstract
The present invention relates to a kind of three-level formula started with no brush/generator three-phase AC excitation system and control methods, three-phase ac exciter stator core and rotor core are cylinder type, exciter rotor is connect with rotating rectifier and main motor rotor coaxial, and exciter stator three-phase symmetric winding and rotor three-phase symmetric winding are axially distributed along starting/generating system.In the electric motor starting stage, the control to main motor exciting current is realized by control three-phase inverter;In power generating stage, the exciting current adjustment of main motor is realized by the duty ratio of the three-phase inverter of control excitation system.The excitation mode control method used in the method for the present invention, it is not necessary that excitation system is adjusted can the constant main motor exciting current of output size in starting process, the control to main motor exciting current can be realized by the excitation voltage and frequency for adjusting travelling-magnetic-field exciter in power generation process, can satisfy main generator under different operational modes to the demand of exciting current.
Description
Technical field
The invention belongs to aviation alternating current generator technical fields, are related to a kind of three-level formula started with no brush/generator three-phase alternating current
Excitation system and control method are novel the encouraging of a kind of three-phase ac exciter based on travelling-magnetic-field and three-phase inverter composition
Magnetic system reaches and meets main generator in different phase to the novel brushless excitation system structure of exciting current different demands and control
Method processed.
Background technique
With the fast development of big aircraft technology, there is starting/generating integrated function wide variable-frequency power generation system of high pressure
It is an important development direction of the following aviation AC power supply system.China's aircraft AC electrical power generating systems mostly use three-level at present
Formula brushless synchronous machine (functional block diagram is shown in Fig. 1) is used as generator, such generator starts without the function of starting aero-engine
Machine is started by independent starter.Such engine-power-supply system include two sets of motors so that its volume and weight compared with
Greatly, and system complex, reliability reduce.If it can be made by control on the basis of original three-level formula no-brush synchronous generator
Motoring condition is operated in complete the starting of engine, that is, realize start/it is generating integrated, so that it may save special starting
Machine mitigates airborne weight and system bulk.
Traditional three-level formula no-brush synchronous generator mainly by main generator, exciter, pilot exciter (permanent magnet generator),
Rotating rectifier is constituted.Main generator is in power generating stage, and the three-phase alternating current that pilot exciter issues is by three-phase uncontrollable rectifier electricity
Road, which is rectified into after direct current, provides excitation for exciter stator winding, and exciter rotor winding induces three-phase alternating current through same
Excitation is provided for main generator rotor excitation winding after the connected rotating rectifier rectification of axis, the cutting of main generator unit stator winding is same
It walks magnetic field and issues three-phase alternating current.The motor predominantly meets generating function design, and in motoring condition, there are the following problems: 1)
When static and lower-speed state, the excitation voltage of excitation system output is lower, main generator excitation electric current is smaller, seriously affects main hair
The loaded starting ability of motor;2) with the raising of motor speed, excitation system output voltage is gradually increased, main generator excitation
Electric current is also gradually increased, i.e. main generator excitation electric current is constantly among variation in motor starting process.
For above-mentioned exciter problem, main solution has both at home and abroad at present: 1, main generator motor is static and low
Fast operation phase, exciter stator winding use single phase ac excitation, and motor is in high-speed cruising or power generating stage, exciter stator
Winding uses DC excitation;2, main generator motor is static and the low speed operation phase, exciter stator winding using two-phase or
Three-phase AC excitation, motor use direct current or single phase ac excitation in high-speed cruising or power generating stage, exciter stator winding;
3, main generator uses two-phase or three-phase AC excitation in starting and power generating stage, exciter stator winding always.1 energy of scheme
It is enough to provide biggish exciting current with low-speed stage main generator is static, but with the development of airplane power source technology and start
Machine needs higher starting torque, and single phase ac excitation mode can no longer meet main generator starting stage to exciting current
Demand.Breath magnetic field in scheme 2 and 3 exciter of scheme is rotating excitation field, the main motor exciting current of excitation system output with
Rotation speed change and the characteristic changed, the strong coupling of Nonlinear Multivariable being had due to excitation system using brushless structure, excitation system
Main motor armature winding in conjunction feature and starting process is connected with inverter, traditional by detecting main motor armature winding
The method that end voltage realizes that main motor exciting current closed loop is adjusted can not be applicable in, and main motor exciting current needs closed-loop control to implement
It is difficult.In order to reduce influence of the revolving speed to main motor exciting current, scheme 2 is needed in starting process by changing excitation mode
Main motor exciting current is limited, but the oscillation of main motor exciting current caused by handoff procedure can seriously affect starting/power generation
The starting performance of system.Scheme 3, in order to limit main motor exciting current, is needed to excitation system in implementation process
Keep revolutional slip constant, but when the revolving speed of system increases to a certain extent, synchronous field direction of rotation will occur anti-in exciter
Turn, exciter is likely to enter power generation mode and carries out reverse charging to field power supply, and field power supply is made to be damaged.
Summary of the invention
Technical problems to be solved
In order to avoid the shortcomings of the prior art, the present invention proposes that a kind of three-level formula started with no brush/generator three intersects
Flow excitation system and control method.
Technical solution
A kind of three-level formula started with no brush/generator three-phase AC excitation system, it is characterised in that: three-phase ac exciter is fixed
Sub- iron core and rotor core are cylinder type, and exciter rotor is connect with rotating rectifier and main motor rotor coaxial,
Without axial relative movement between exciter stator and rotor;The three of the three-phase symmetric winding of three-phase ac exciter stator, rotor
Symmetrical winding is distributed along the axial direction of starting/generator, and exciter stator winding connect generation with three-phase inverter along axial direction
Travelling-magnetic-field, exciter rotor winding cut the three-phase induction electricity that travelling-magnetic-field generates and rectify through coaxially connected rotating rectifier
To provide exciting current after direct current for main motor excitation winding.
One three-phase inverter constitutes the power inverter of excitation system.
The two-way inverter of three-phase is the two-way inverter of three phase full bridge or the two-way inverter of three-phase half-bridge.
A method of controlling the three-level formula started with no brush/generator three-phase AC excitation system, it is characterised in that:
The electric motor starting stage: exciter stator winding is three-phase Y type connection type, the DC bus and boat of three-phase inverter
Empty DC power supply is connected, and the exchange side of three-phase inverter is connected with exciter stator three-phase windings;With SPWM technical controlling three-phase
Inverter works in inverter mode, provides three-phase AC excitation voltage for exciter;Three-phase inverter is controlled to realize to main motor
The control of exciting current
In the electric power generation operation phase: the direct current side bus of three-phase inverter is switched to secondary excitation from 270V DC power supply
The electric energy of the DC output end of machine stator side rectifier, three-phase inverter is provided by pilot exciter;Change accounting for for three-phase inverter
Exciting current adjustment of the sky than realizing main motor.
Beneficial effect
A kind of three-level formula started with no brush/generator three-phase AC excitation system and control method proposed by the present invention, three-phase
AC exciter stator core and rotor core are that cylinder type, exciter rotor and rotating rectifier and main motor turn
Son is coaxially connected, and exciter stator three-phase symmetric winding and rotor three-phase symmetric winding are axially distributed along starting/generating system.
In the electric motor starting stage, the control to main motor exciting current is realized by control three-phase inverter;In power generating stage, pass through control
The duty ratio of the three-phase inverter of excitation system processed realizes the exciting current adjustment of main motor.
The method of the present invention has the advantages that
1) it uses a stylobate in the three-phase exciter of travelling-magnetic-field in the present invention, is started in main generator equal with power generation process
As main exciter, the main motor exciting current of excitation system output does not change with system revolving speed and is changed.
2) the excitation mode control method used in the method for the present invention, without being adjusted to excitation system in starting process
Section can output size constant main motor exciting current, can be encouraged by adjusting travelling-magnetic-field exciter in power generation process
Magnetoelectricity pressure realizes the control to main motor exciting current with frequency, can satisfy main generator under different operational modes to excitation
The demand of electric current.
Detailed description of the invention
Fig. 1: three-level formula brushless synchronous power generation system structure figure
Fig. 2: brushless excitation system structure chart
Fig. 3: travelling-magnetic-field exciter structure chart
1- rotor windings, 2- stator winding, 3- stator core, 4- rotor core, 5- shaft
Fig. 4: when exciter is static, exciter three-phase AC excitation phase voltage chopping voltage
Fig. 5: when exciter is static, main motor rotor excitation current waveform
Fig. 6: when exciter 8000rpm revolving speed, exciter stator excitation voltage waveform
Fig. 7: when exciter 8000rpm revolving speed, main motor excitation current waveform
Specific embodiment
Now in conjunction with embodiment, attached drawing, the invention will be further described:
In the starting of three-level formula started with no brush/generator and power generating stage, in order to which the main motor for exporting excitation system is encouraged
Magnetoelectricity stream does not change with revolving speed and changes and meet main motor in the excitation demand of different phase simultaneously, excitation system not only need and
Revolving speed decoupling is provided simultaneously with stronger excitation fan-out capability.
In order to meet the main motor exciting current of excitation system output and the requirement of revolving speed decoupling, while meeting main generator
Demand to exciting current, three-level formula started with no brush proposed by the present invention/generator three-phase AC excitation system: exciter stator
Three-phase symmetric winding, rotor three-phase symmetric winding are distributed along the axial direction of starting/generator, exciter stator winding and three contraries
Become device to connect and generate along axial travelling-magnetic-field, it is coaxial that exciter rotor winding cuts the three-phase induction electricity warp that travelling-magnetic-field generates
The rotating rectifier of connection, which is rectified into after direct current, provides exciting current for main motor excitation winding.Due to exciter it is fixed/rotor around
It is coupled between group by travelling-magnetic-field, therefore excitation system has stronger fan-out capability, while the main electricity of excitation system output
Machine exciting current does not change with revolving speed and is changed.
For the feasibility and validity for verifying the method for the present invention, simulating, verifying is carried out using Magnet 6.0.Fig. 3 be
The three-phase ac exciter finite element model established in Magnet software: exciter is pivot-rotatable type structure, 2 pairs of poles;Rotor core
12 slots, three-phase distribution, the number of turns that is often connected in series are 24 circles, and three-phase windings connect resistance inductive load by full-bridge rectification and (simulate main power generation
Machine excitation winding);12 slot of stator core, three-phase distribution, the number of turns that is often connected in series are 60 circles.
Three-phase ac exciter stator core and rotor core are cylinder type, exciter rotor and rotating rectifier
And the connection of main motor rotor coaxial, without axial relative movement between exciter stator and rotor;Three-phase ac exciter stator
Three-phase symmetric winding, rotor three-phase symmetric winding along starting/generator axial direction be distributed, exciter stator winding and three
Phase inverter is connected and is generated along axial travelling-magnetic-field, and exciter rotor winding cuts the three-phase induction electricity warp that travelling-magnetic-field generates
Coaxially connected rotating rectifier, which is rectified into after direct current, provides exciting current, a three-phase inverter structure for main motor excitation winding
At the power inverter of excitation system.It is two-way inverse that the two-way inverter of three-phase can be the two-way inverter of three phase full bridge, three-phase half-bridge
Become device.
As shown in Fig. 2, two contact relays are connected to normally opened contact a1 and a2 in the electric motor starting stage, three-phase bridge is inverse
Become device DC bus to be connected by relay with aviation DC bus, inverter ac side and travelling-magnetic-field exciter stator three-phase
Winding link.Exciter stator three-phase A, B, C winding is connected respectively to excitation system inverter ac side three-phase bridge arm.Excitation system
Energy of uniting passes through three-phase bridge type converter from DC bus and flows into exciter, and exciter rotor winding cuts axial travelling-magnetic-field and produces
Raw induced potential provides DC excitation after rotating rectifier is whole for direct current for main motor excitation winding.Since travelling-magnetic-field is encouraged
Axial displacement does not occur between magnetomechanical rotor and stator, therefore the main motor exciting current of excitation system output is not with rotation speed change
And change.
In this example, exciter inverter ac side DC bus-bar voltage is 270VDC, inverter ac side output voltage
Phase voltage 115VAC, three-phase bridge type converter are obtained by SPWM control technology, as shown in Figure 4.When motor is static, process is limited
First simulation calculation, main generator excitation winding current are 55A, as shown in figure 5, can satisfy main generator starts demand.In electricity
In machine starting process, the constant main motor exciting current that can make excitation system output constant size of inverter duty cycle is kept.
In the electric power generation stage, two contact relays are connected to normally-closed contact b1 and b2, and three-phase bridge type converter direct current is female
Line is connected by relay with the output of the rectifier DC of pilot exciter stator side, inverter ac side and travelling-magnetic-field exciter
Three-phase stator winding link.Main motor exciting current can by adjust travelling-magnetic-field exciter excitation voltage amplitude with
Frequency is realized.
In this example, exciter stator exciting current is that frequency 400Hz is obtained, wave by excitation system three-phase inverter
Shape is as shown in Figure 6.By FEM calculation, when motor speed is 8000rpm, main generator excitation winding current is 55A, waveform
As shown in fig. 7, can satisfy system requirements.For system in power generation process, the control of main generator excitation electric current can pass through tune
The excitation voltage amplitude and frequency for saving exciter stator winding are realized.
Claims (4)
1. a kind of three-level formula started with no brush/generator three-phase AC excitation system, it is characterised in that: three-phase ac exciter stator
Iron core and rotor core are cylinder type, and exciter rotor connect with rotating rectifier and main motor rotor coaxial, encourages
Without axial relative movement between magnetomechanical stator and rotor;The three-phase of the three-phase symmetric winding of three-phase ac exciter stator, rotor
Symmetric winding is distributed along the axial direction of starting/generator, and exciter stator winding connect generation with three-phase inverter along axial row
Wave magnetic field, the three-phase induction electricity that exciter rotor winding cutting travelling-magnetic-field generates are rectified into through coaxially connected rotating rectifier
Exciting current is provided after direct current for main motor excitation winding.
2. three-level formula started with no brush/generator three-phase AC excitation system according to claim 1, it is characterised in that: described
One three-phase inverter constitutes the power inverter of excitation system.
3. three-level formula started with no brush/generator three-phase AC excitation system according to claim 1, it is characterised in that: described
The two-way inverter of three-phase is the two-way inverter of three phase full bridge or the two-way inverter of three-phase half-bridge.
4. a kind of three-level formula started with no brush/generator three-phase AC excitation system method described in control claim 1, feature
It is:
The electric motor starting stage: exciter stator winding is three-phase Y type connection type, and the DC bus of three-phase inverter and aviation are straight
Galvanic electricity source is connected, and the exchange side of three-phase inverter is connected with exciter stator three-phase windings;With SPWM technical controlling three-phase inversion
Device works in inverter mode, provides three-phase AC excitation voltage for exciter;Three-phase inverter is controlled to realize to main motor excitation
The control of electric current
In the electric power generation operation phase: the direct current side bus of three-phase inverter being switched to pilot exciter from 270V DC power supply and is determined
The electric energy of the DC output end of sub- side rectifier, three-phase inverter is provided by pilot exciter;Change the duty ratio of three-phase inverter
Realize the exciting current adjustment of main motor.
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Cited By (8)
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CN110401387A (en) * | 2019-08-13 | 2019-11-01 | 福建凯威斯发电机有限公司 | A kind of bifrequency switching generator |
CN111857197A (en) * | 2020-07-30 | 2020-10-30 | 南京邮电大学 | Three-phase alternating current motor and load simulation method and device thereof |
CN112234886A (en) * | 2020-08-27 | 2021-01-15 | 贵州恒芯微电子科技有限公司 | Reverse excitation method of starting all-in-one machine |
CN112968634A (en) * | 2021-02-02 | 2021-06-15 | 哈尔滨工业大学 | Synchronous motor excitation system |
CN113162354A (en) * | 2021-04-30 | 2021-07-23 | 陕西航空电气有限责任公司 | Brushless electric excitation synchronous generator with wide rotating speed range |
CN113472256A (en) * | 2021-07-05 | 2021-10-01 | 西北工业大学 | Excitation controller of aviation three-stage starting power generation system and rotor position estimation method |
CN117630664A (en) * | 2023-12-08 | 2024-03-01 | 南京航空航天大学 | Current detection method and system for excitation of main motor of aviation three-stage generator |
EP4401302A1 (en) * | 2023-01-13 | 2024-07-17 | Hamilton Sundstrand Corporation | Starter/generator arrangements for gas turbine engines |
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CN111857197A (en) * | 2020-07-30 | 2020-10-30 | 南京邮电大学 | Three-phase alternating current motor and load simulation method and device thereof |
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CN117630664A (en) * | 2023-12-08 | 2024-03-01 | 南京航空航天大学 | Current detection method and system for excitation of main motor of aviation three-stage generator |
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