CN104767446B - A kind of hybrid exciting synchronous motor air-gap flux and electric current phasor angle control method - Google Patents

Abstract

The invention discloses a kind of hybrid exciting synchronous motor air-gap flux and electric current phasor angle control method, by controlling d shaft currents i_d, q shaft currents i_qWith exciting current i_f, keep air-gap flux to be equal to 90 ° with electric current phasor angle θ.Motor operation controls i according to load control in low regime_d、i_qAnd i_fθ is made to be equal to 90 °.When load torque is less than nominal torque, exciting current is 0, by controlling i_dAnd i_qθ is made to be equal to 90 °；When load torque is more than nominal torque, by coordinating i_d、i_qAnd i_fθ is made to be equal to 90 °.Motor operation when high velocity, using i_dWith i_fCommon weak magnetic, by i_d、i_qAnd i_fCoordinate control θ and be equal to 90 °.Hybrid exciting synchronous motor air-gap flux makes the capacity of inverter be fully used with electric current phasor angle control method, and relatively low to stator voltage and voltammetric capacity requirement, is particularly well-suited to high-power and Large Copacity governing system.

Description

A kind of hybrid exciting synchronous motor air-gap flux and electric current phasor angle control method

Technical field

The invention belongs to electric drive technology field, is related to a kind of air-gap flux and electric current phasor angle control policy, especially It is to be related to a kind of hybrid exciting synchronous motor control method.

Background technology

Hybrid exciting synchronous motor is that the one kind grown up on the basis of permanent-magnet synchronous with electric excitation synchronous motor is wide Buncher, its main purpose are to solve the problems, such as that permagnetic synchronous motor air-gap field is difficult to adjust.Composite excitation synchronization Motor has two kinds of excitation sources, and one kind is permanent magnet, and another kind is electrical excitation, magnetic potential based on the magnetic potential that permanent magnet is produced, excitation Magnetic potential supplemented by the magnetic potential that winding is produced.This motor combines the advantage of permanent-magnet synchronous and electric excitation synchronous motor, two kinds of excitations Source interacts in motor gas-gap and produces main flux, when electrical excitation coil is passed through the exciting current of forward direction, produces positive electricity Magnetic torque and increase motor torque；Conversely, when electrical excitation coil is passed through reverse exciting current, then producing opposing magnetic field and weakening Air-gap field reaches the purpose of weak magnetic speed-up, so as to widen the speed adjustable range of motor.

At present, it is less for hybrid exciting synchronous motor control method and Research on Driving System both at home and abroad, related data It is not a lot.Based on vector controlled, four classes can be classified as substantially, one is i_d=0 control, two is weak magnetic control, and three is that efficiency is excellent Change control, four is unity power factor control.The advantage of first three class control method is simple and convenient, output-constant operation wide ranges, Row area efficiency for the national games is high；Have the disadvantage the problems such as power factor is reduced, and terminal voltage is raised.Although unity power factor control is improved The power factor of control system, but voltammetric capacity has high demands, and equally stator voltage is required also higher.And both at home and abroad for mixed Close excitation magnetic synchronization motor air-gap flux space state is substantially at the control research of electric current phasor angle.

The content of the invention

Technical problem：The present invention proposes one kind, and no matter hybrid exciting synchronous motor operates in low regime or high velocity, Air-gap flux and electric current phasor angle are all kept equal to 90 °, reduce control system to the demand of stator voltage and voltammetric capacity, carry The hybrid exciting synchronous motor air-gap flux and electric current phasor angle control method of high grid power transmission efficiency.

Technical scheme：Hybrid exciting synchronous motor air-gap flux and the electric current phasor angle control method of the present invention, including with Lower step：

(1) phase current i is gathered from motor main circuit_a、i_bWith exciting current i_f, initial position detection is carried out to motor, from electricity Signal is gathered on machine encoder, controller is sent into and is processed, draw rotating speed n and rotor position angle θ；

(2) by the phase current i of collection_a、i_bJing is followed, is filtered, biasing and A/D conversions, is then carried out park transforms, is obtained Stator d shaft currents i under two-phase rotating coordinate system_dWith q shaft currents i_q；

(3) use given rotating speed n^*Encoder actual measurement rotating speed n is deducted, by the rotating speed deviation △ n input speed actuators for obtaining, Torque reference value is obtained Jing after proportional integral computingBy torque reference valueActual measurement rotating speed n and given rotating speed n^*Input current According to rotating speed, allotter, judges that motor operation is interval：When actual speed is less than rated speed, then hybrid exciting synchronous motor is transported In low regime, into step (4), otherwise, hybrid exciting synchronous motor runs on high velocity to row, into step (5)；

(4) judge whether load torque meets T_L≤T_N, wherein T_LFor load torque, T_NFor nominal torque；

Work as T_L≤T_NWhen, magnetic control, i need not be increased_fref=0, keep the angle theta between air gap synthesis magnetic linkage and electric current phasor Equal to 90 °, solved according to following equations group and calculate d shaft current reference values i_dref, q shaft current reference values i_qrefJoin with exciting current Examine value i_fref, the current sharing scheme output current that distributing switch is obtained according to solution, subsequently into step (6)：

Work as T_L>T_NWhen, increasing magnetic control is carried out, is solved according to following equations group and is calculated d shaft current reference values i_dref, q shaft currents Reference value i_qrefWith exciting current reference value i_fref, the current sharing scheme output current that distributing switch is obtained according to solution, so Step (6) is entered afterwards：

Wherein, ψ_exc=ψ_m+M_fi_fref, i_drefFor d shaft current reference values, i_qrefFor q shaft current reference values, i_frefFor excitation Current reference value；ψ_mFor permanent magnet flux linkage, p is motor number of pole-pairs；I_fNFor exciting current rated value, L_d、L_qRespectively stator winding D axles and q axle inductances, M_fFor the mutual inductance between armature winding and Exciting Windings for Transverse Differential Protection, T_erefFor electromagnetic torque reference value；

(5) using d shaft currents i_dWith exciting current i_fWeak magnetic, keeps between air gap synthesis magnetic linkage and electric current phasor simultaneously Angle theta be equal to 90 °, distributing switch according to following current sharing scheme output current, into step (6)：

Wherein, ω_eFor angular rate, U_dcFor busbar voltage；

(6) with d shaft current reference values i produced by distributing switch_drefDeduct d shaft currents i in step (2)_dObtain d Shaft current deviation △ i_d, with q shaft current reference values i_qrefDeduct q shaft currents i in step (2)_qObtain q shaft current deviation △ i_q, By the d shaft current deviations △ i_dInput d shaft currents actuator carries out proportional integral computing, obtains d shaft voltage u_d, by the q axles Current deviation △ i_qInput q shaft currents actuator carries out proportional integral computing, obtains q shaft voltage u_q, then to the d shaft voltages u_dWith q shaft voltage u_qAfter carrying out jointly rotating orthogonal-static two phase inversion, α shaft voltage u under static two phase coordinate system are obtained_αAnd β Shaft voltage u_β, by the α shaft voltages u_αWith β shaft voltage u_βInput pulse width modulation module, 6 tunnel pulse width of computing output are adjusted Signal processed, drives main power inverter；

Simultaneously by the exciting current i of collection in step (1)_f, Jing follow, filter, bias with A/D conversion after and exciting current Reference value i_frefDC excitation pulse width modulation module is sent into together, and computing exports 4 road pulse width modulating signals to drive excitation Power inverter.In a kind of preferred version of the inventive method, step 6) in Pulse width modulation module be space vector arteries and veins Rush width modulation module.

Beneficial effect：The i of existing hybrid exciting synchronous motor_d=0 and efficiency-optimized control method there are shortcomings, its One of be exactly that the power factor of motor reduces therewith with the increase of load；Although unity power factor control improves control The power factor of system processed, but while stator voltage and voltammetric capacity are required higher.The present invention passes through step (4) and step (5) air-gap flux and electric current phasor angle control method, make no matter hybrid exciting synchronous motor operates in low regime or high speed Area, all keeps air-gap flux to be equal to 90 ° with electric current phasor angle.The control method is at aspects such as output torque, efficiency, power factors The characteristics of and unity power factor control relatively, but the requirement much lower to electric moter voltage and voltammetric capacity, thus this The relatively existing control method of invention has advantages below：

The power factor of the method control system is about 1, makes inverter be fully used, and improves the transmission of electricity effect of electrical network Rate；

It is 1 control relative to power factor, this method reduces demand of the control system to stator voltage；

It is 1 control relative to power factor, this method reduces demand of the control system to voltammetric capacity；

So hybrid exciting synchronous motor air-gap flux and electric current phasor angle control Large Copacity, high-power speed-adjusting system, There is certain application prospect in high-speed electric expreess locomotive field.

Description of the drawings

Fig. 1 is the logical procedure diagram of the inventive method；

Fig. 2 is the system block diagram of the inventive method；

Fig. 3 is the structured flowchart for realizing the inventive method；

Fig. 4 is hybrid exciting synchronous motor vector diagram.

Specific embodiment

With reference to embodiment and Figure of description, the present invention is further illustrated.

Fig. 3 is the system frame for realizing hybrid exciting synchronous motor air-gap flux of the present invention and electric current phasor angle control method Figure, the control system by alternating current power supply, commutator, electric capacity of voltage regulation, dsp controller, main power inverter, auxiliary power inverter, Sensor, hybrid exciting synchronous motor, photoelectric encoder etc. are constituted.

Alternating current power supply is powered to whole system, and after rectifier rectification, main and auxiliary power conversion is given in filtering, voltage stabilizing Device, Hall voltage sensor collection busbar voltage, sends into controller after conditioning.The output termination mixing of main and auxiliary power inverter Excitation magnetic synchronization motor, Hall current transformer collection phase current and exciting current, send into controller after conditioning, code device signal is adopted Collection rotating speed and rotor-position signal, send into controller and calculate rotor position angle and rotating speed after process.Controller exports 10 road PWM letters Main, exciting power changer is driven number respectively.

The hybrid exciting synchronous motor air-gap flux of the present invention controls control method with electric current phasor angle, shown in Fig. 3, specifically Comprise the following steps：

(1) three Hall current sensor gathers phase current i from motor main circuit respectively_a、i_bWith exciting current i_f, will adopt The signal for collecting sends into controller Jing after the signal conditions such as voltage follow, filtering, biasing and overvoltage protection, and motor is carried out accurately Initial position detection, gathers signal from motor encoder, processes feeding controller and calculates rotating speed n and rotor position angle θ；

(2) will be fed into the phase current i of controller_a、i_bA/D conversions are carried out, through three phase coordinate systems to two-phase rotating coordinate system Park transforms obtain d shaft currents i under two-phase rotating coordinate system_dWith q shaft currents i_q；

(3) use given rotating speed n^*Deduct encoder actual measurement rotating speed n, after obtain rotating speed deviation △ n, rotating speed deviation △ n is entered Torque reference value is obtained after speed regulatorBy torque reference valueActual measurement rotating speed n and given rotating speed n^*Send into electric current distribution Whether device, judge actual speed less than rated speed, and in this way, motor operation in low regime, into step (4), otherwise, transport by motor Go in high velocity, into step (5)；

(4) judge whether load torque meets T_L≤T_N, T_LFor load torque, T_NFor nominal torque；

Lower surface analysis low regime hybrid exciting synchronous motor air-gap flux and electric current phasor angle control principle, according to vector control Principle processed, in d-q coordinate systems, draws the mathematical model of hybrid exciting synchronous motor.

Flux linkage equations：

Voltage equation：

Electromagnetic torque equation：

Wherein, i_d、i_qRespectively d axles and q shaft currents, I_sFor rated current, i_fFor exciting current；L_d、L_qRespectively d axles with Q axle inductances, M_fFor the mutual inductance between armature and Exciting Windings for Transverse Differential Protection；ω_eFor angular rate；ψ_mFor permanent magnet flux linkage, p is that motor is extremely right Number, u_d、u_qThe respectively voltage of d axles and q axles, u_fFor Exciting Windings for Transverse Differential Protection voltage；R_sFor armature winding resistance, R_fFor Exciting Windings for Transverse Differential Protection electricity Resistance；ψ_d、ψ_q、ψ_fDifference d axles, q axles and Exciting Windings for Transverse Differential Protection magnetic linkage；T_eFor electromagnetic torque.

Hybrid exciting synchronous motor phasor diagram is as shown in figure 4, it can be seen that can obtain following equation

According to formula (4), electromagnetic torque T_eCan be expressed as

Wherein, θ is the angle that air gap synthesizes between magnetic linkage and electric current phasor, and δ is power angle, and β is angle of torsion, ψ_sFor air gap Synthesis magnetic linkage, i_sFor stator current vector.

From formula (5) as can be seen that the angle theta between control air gap synthesis magnetic linkage and electric current phasor can just control electromagnetism turn Square.

The invention control air gap synthesis magnetic linkage and electric current phasor angle θ=90 °, can obtain

So as to obtain

Sin β=cos δ (7)

Work as T_L≤T_NWhen, magnetic control need not be increased, so exciting current i_f=0, θ=90 ° are kept, is obtained

D shaft current reference values i are calculated according to above formula_dref, q shaft current reference values i_qrefWith exciting current reference value i_frefFor

Electric current distribution is carried out according to above formula, step (6) is directly entered.

Work as T_L>T_NWhen, increasing magnetic control is carried out, θ=90 ° is kept, can be obtained

Wherein, ψ_exc=ψ_m+M_fi_fref

D shaft current reference values i are calculated according to above formula then_dref, q shaft current reference values i_qrefWith exciting current reference value i_fref For

Electric current distribution is carried out according to above formula, step (6) is directly entered.

(5) using d shaft currents i_dWith exciting current i_fWeak magnetic, keeps θ=90 ° simultaneously, and it is anti-electric that weak magnetic calculating formula ignores d axles Gesture, then have

D shaft current reference values i are calculated according to above formula_dref, q shaft current reference values i_qrefWith exciting current reference value i_frefFor

Electric current distribution is carried out according to above formula, step (6) is directly entered.

(6) with d shaft current reference values i produced by distributing switch_drefDeduct d shaft currents i in step (2)_dObtain d Shaft current deviation △ i_d, with q shaft current reference values i_qrefDeduct q shaft currents i in step (2)_qObtain q shaft current deviation △ i_q, By d shaft current deviation △ i_dInput d shaft currents actuator carries out proportional integral computing, obtains d shaft voltage u_d, by q shaft current deviations △i_qInput q shaft currents actuator carries out proportional integral computing, obtains q shaft voltage u_q, then to the d shaft voltages u_dWith q axles electricity Pressure u_qAfter carrying out jointly rotating orthogonal-static two phase inversion, α shaft voltage u under static two phase coordinate system are obtained_αWith β shaft voltage u_β, By the α shaft voltages u_αWith β shaft voltage u_βInput pulse width modulation module, computing export 6 road pulse width modulating signals, drive Move main power inverter；Simultaneously by the exciting current i of collection in step (1)_f, Jing follow, filter, bias with A/D conversion after and Exciting current reference value i_frefDC excitation pulse width modulation module is sent into together, and computing exports 4 road pulse width modulating signals and comes Drive exciting power changer.

Above-described embodiment is only the preferred embodiment of the present invention, it should be pointed out that：For the ordinary skill of the art For personnel, under the premise without departing from the principles of the invention, some improvement and equivalent can also be made, these are to the present invention Claim is improved and the technical scheme after equivalent, each falls within protection scope of the present invention.

Claims (2)

1. a kind of hybrid exciting synchronous motor air-gap flux and electric current phasor angle control method, it is characterised in that the method includes Following steps：

(1) phase current i is gathered from motor main circuit_a、i_bWith exciting current i_f, initial position detection is carried out to motor, is compiled from motor Signal is gathered on code device, controller is sent into and is processed, draw rotating speed n and rotor position angle θ；

(2) by the phase current i of collection_a、i_bJing is followed, is filtered, biasing and A/D conversions, is then carried out park transforms, is obtained biphase Stator d shaft currents i under rotating coordinate system_dWith q shaft currents i_q；

(3) use given rotating speed n^*Encoder actual measurement rotating speed n is deducted, by the rotating speed deviation △ n input speed actuators for obtaining, Jing ratios Torque reference value is obtained after example integral operationBy torque reference valueActual measurement rotating speed n and given rotating speed n^*Input current distributes According to rotating speed, device, judges that motor operation is interval：When actual speed is less than rated speed, then hybrid exciting synchronous motor runs on Low regime, into step (4), otherwise, hybrid exciting synchronous motor runs on high velocity, into step (5)；

(4) judge whether load torque meets T_L≤T_N, wherein T_LFor load torque, T_NFor nominal torque；

Work as T_L≤T_NWhen, magnetic control, i need not be increased_fref=0, keep the angle theta between air gap synthesis magnetic linkage and electric current phasor to be equal to 90 °, solved according to following equations group and calculate d shaft current reference values i_dref, q shaft current reference values i_qrefWith exciting current reference value i_fref, the current sharing scheme output current that distributing switch is obtained according to solution, subsequently into step (6)：

$\left\{\begin{array}{c}{i}_{dref}=\frac{-{\mathrm{\ψ}}_m-\sqrt{{\mathrm{\ψ}}_m^2+4L_d{L}_q{i}_{qref}^2}}{2L_d}\\ i_{qref}=\frac{2T_{eref}}{3p\[{\mathrm{\ψ}}_m+\left(L_d-L_q\right)\left(\frac{-{\mathrm{\ψ}}_m-\sqrt{{\mathrm{\ψ}}_m^2+4L_d{L}_q{i}_{qref}^2}}{2L_d}\right)\]}\\ i_{fref}=0\end{array}\right.$

Work as T_L>T_NWhen, increasing magnetic control is carried out, is solved according to following equations group and is calculated d shaft current reference values i_dref, q shaft currents reference Value i_qrefWith exciting current reference value i_fref, the current sharing scheme output current that distributing switch is obtained according to solution, Ran Houjin Enter step (6)：

$\left\{\begin{array}{c}{i}_{dref}=\frac{-{\mathrm{\ψ}}_{exc}-\sqrt{{\mathrm{\ψ}}_{exc}^2+4L_d{L}_q{i}_{qref}^2}}{2L_d}\\ i_{qref}=\frac{2T_{eref}}{3p\[{\mathrm{\ψ}}_{exc}+\left(L_d-L_q\right)\left(\frac{-{\mathrm{\ψ}}_{exc}-\sqrt{{\mathrm{\ψ}}_{exc}^2+4L_d{L}_q{i}_{qref}^2}}{2L_d}\right)\]}\\ i_{fref}=I_{fN}\end{array}\right.$

Wherein, ψ_exc=ψ_m+M_fi_fref, i_drefFor d shaft current reference values, i_qrefFor q shaft current reference values, i_frefFor exciting current Reference value；ψ_mFor permanent magnet flux linkage, p is motor number of pole-pairs；I_fNFor exciting current rated value, L_d、L_qRespectively stator winding d axles With q axle inductances, M_fFor the mutual inductance between armature winding and Exciting Windings for Transverse Differential Protection, T_erefFor electromagnetic torque reference value；

(5) using d shaft currents i_dWith exciting current i_fWeak magnetic, keeps the angle theta between air gap synthesis magnetic linkage and electric current phasor simultaneously Equal to 90 °, distributing switch according to following current sharing scheme output current, into step (6)：

$\left\{\begin{array}{c}{i}_{dref}=\frac{\frac{U_{dc}}{\sqrt{3}{\mathrm{\ω}}_e}-\left({\mathrm{\ψ}}_m+M_f{i}_{fref}\right)}{L_d}\\ i_{qref}=\sqrt{\frac{i_{dref}\[{\mathrm{\ψ}}_m+L_d{i}_{dref}+M_f{i}_{fref}\]}{L_q}}\\ i_{fref}=\frac{\frac{2T_{eref}}{3{\mathrm{pi}}_{qref}}-\[{\mathrm{\ψ}}_m+i_{dref}\left(L_d-L_q\right)\]}{M_f}\end{array}\right.$

Wherein, ω_eFor angular rate, U_dcFor busbar voltage；

(6) with d shaft current reference values i produced by distributing switch_drefDeduct d shaft currents i in step (2)_dObtain d axles electricity Stream deviation △ i_d, with q shaft current reference values i_qrefDeduct q shaft currents i in step (2)_qObtain q shaft current deviation △ i_q, by institute State d shaft current deviation △ i_dInput d shaft currents actuator carries out proportional integral computing, obtains d shaft voltage u_d, by the q shaft currents Deviation △ i_qInput q shaft currents actuator carries out proportional integral computing, obtains q shaft voltage u_q, then to the d shaft voltages u_dAnd q Shaft voltage u_qAfter carrying out jointly rotating orthogonal-static two phase inversion, α shaft voltage u under static two phase coordinate system are obtained_αWith β shaft voltages u_β, by the α shaft voltages u_αWith β shaft voltage u_βInput pulse width modulation module, computing export 6 road pulse width modulating signals, Drive main power inverter；

Simultaneously by the exciting current i of collection in step (1)_f, refer to exciting current Jing following, filtering, bias with after A/D conversions Value i_frefDC excitation pulse width modulation module is sent into together, and computing exports 4 road pulse width modulating signals to drive exciting power Changer.

2. hybrid exciting synchronous motor air-gap flux according to claim 1 and electric current phasor angle control method, its feature Be, the step 6) in Pulse width modulation module be space vector pulse width modulation module.