CN105262404A - Electromechanical coupling control equipment and method for pure electric vehicle power transmission system - Google Patents

Abstract

The invention relates to electromechanical coupling control equipment for a pure electric vehicle power transmission system. The electromechanical coupling control equipment comprises a motor control device, a transmission system and a current parameter adjusting device, wherein the motor control device is used for outputting a motor torque, a motor rotor corner and motor current according to a target torque; the transmission system is connected with the motor control device and is used for obtaining a motor rotating speed according to the motor torque and transmitting the motor rotating speed to the motor control device for a feedback control on the motor torque; and the current parameter adjusting device is connected with the motor control device and is used for generating adjusting current according to the motor torque, the motor rotor corner and the motor current and transmitting the adjusting current to the motor control device for a feedback adjustment on the motor torque. Compared with the prior art, the feedback control is respectively carried out on the motor control device by the transmission system and the current parameter adjusting device through the motor rotating speed and the adjusting current; the control is finally carried out on vehicle power in an electromechanical coupling manner; the adjustment can be carried out on the motor torque; and the control on the speed of a vehicle is relatively accurate.

Description

A kind of pure electric vehicle power drive system mechanical-electric coupling control appliance and method

Technical field

The present invention relates to a kind of electrical vehicular power control technology, especially relate to a kind of pure electric vehicle power drive system mechanical-electric coupling control appliance and method.

Background technology

The power drive system of centralized driving formula pure electric vehicle is different from conventional internal combustion rolling stock.Dynamical system and drive system direct-coupling, power motor actuating speed is fast, torque response slope is large, easily causes drive system and impacts and twisting vibration, occur longitudinal chattering phenomenon when electric motor car is worked.

Automobile motor kind comprises direct current machine, AC induction motor, permagnetic synchronous motor and switched reluctance machines, wherein, and features such as permagnetic synchronous motor is little with its volume, performance good, structure is simple, reliability is high, Driving Torque is large and being widely used.But no matter be that motor body or control system inevitably exist certain deviation compared with ideal situation in actual applications, therefore the pulsation of the Driving Torque of permagnetic synchronous motor also certainly exists.The parameter of electric machine also has impact to power drive system twisting vibration.

Electric motor car is driven by the electromagnetic torque produced between drive motors rotor, and the applying of torque will cause axle system and impact, and then cause the twisting vibration of axle system at drive system resonance point.In electromagnetic torque, the Monomial coefficient of electric corner is defined as ELECTROMAGNETIC STIFFNESS, and determined by the distinctive performance of motor, stators and rotators links together by ELECTROMAGNETIC STIFFNESS, makes stators and rotators and follow-up drive disk assembly form a unified entirety.The power driving system for electric vehicle natural frequencies (0Hz ~ 2Hz) that ELECTROMAGNETIC STIFFNESS and branch cause, by causing vehicle drive system to produce resonance under motor speed corresponding to low order characteristic frequency and the speed of a motor vehicle, causes car load extensional vibration.

Summary of the invention

Object of the present invention be exactly in order to overcome above-mentioned prior art exist defect and a kind of pure electric vehicle power drive system mechanical-electric coupling control appliance and method are provided.

Object of the present invention can be achieved through the following technical solutions:

A kind of pure electric vehicle power drive system mechanical-electric coupling control appliance, comprising:

Motor control assembly, for according to the torque of target torque output motor, rotor corner and current of electric;

Drive system, is connected with motor control assembly, for obtaining motor speed according to motor torque, and this motor speed is sent to motor control assembly FEEDBACK CONTROL motor torque;

Current parameters adjusting device, is connected with motor control assembly, for generating adjustment electric current according to motor torque, rotor corner and current of electric, and adjustment electric current is sent to motor control assembly feedback regulation motor torque.

Described motor control assembly comprises:

Control strategy module, receiving target torque, and by maximum torque per ampere control method, target torque is converted to two-phase current signal;

Space vector modulation module, is connected with control strategy module and current parameters adjusting device respectively, two-phase current signal and adjustment electric current is integrated and is modulated to two phase voltages;

Inverter module, is connected with space vector modulation module and transfer system respectively, for generating current of electric, motor torque and rotor corner according to motor speed and two phase voltages.

Described drive system comprise connect successively rotor, armature spindle, subtract differential mechanism, discrete axle group and tire sets.

Described subtract differential mechanism comprise connect successively subtract differential input shaft, subtract differential mechanism jack shaft and subtract differential output shaft.

Described discrete axle group comprises discrete left half axle and discrete right axle shaft, and described tire sets comprises revolver and rightly to take turns, one end of described discrete left half axle and discrete right axle shaft all with subtract differential mechanism and be connected, the other end is connected with revolver and right wheel respectively.

A control method for pure electric vehicle power drive system mechanical-electric coupling control appliance, comprises step:

A. motor control assembly receiving target torque, motor torque, rotor corner and current of electric is generated according to target torque, and motor torque is sent to drive system, motor torque, rotor corner and current of electric are all sent to current parameters adjusting device;

B. current parameters adjusting device generates adjustment electric current according to motor torque, rotor corner and current of electric, and adjustment electric current is sent to motor control assembly feedback regulation motor torque;

C. drive system obtains motor speed according to motor torque, and this motor speed is sent to motor control assembly FEEDBACK CONTROL motor torque.

Specifically step is comprised under the participation that described steps A controls at current of electric and motor rotate speed feedback:

A1. control strategy module receiving target torque, and by maximum torque per ampere control method, target torque is converted to two-phase current signal;

A2. space vector modulation module receives two-phase current signal and adjustment electric current, two-phase current signal and adjustment electric current is integrated and is modulated to two phase voltages, and this two phase voltage is sent to inverter module;

A3. inverter module generates current of electric, motor torque and rotor corner according to motor speed and two phase voltages, and current of electric and rotor corner are sent to current parameters adjusting device, motor torque is sent to current parameters adjusting device and drive system respectively.

Described steps A 2 specifically comprises step:

A21. space vector modulation module receives two-phase current signal and adjustment electric current;

A22. two-phase current signal voltage is obtained after two-phase current signal and the superposition of adjustment electric current;

A23. obtain two phase voltages after two-phase current signal voltage being converted and processed, and this two phase voltage is sent to inverter module.

In described steps A 23, the process that two-phase current signal voltage converts and processes is specially:

U ₂＝U ₁·T ₁·T ₂

Wherein: U ₂be two phase voltages, U ₁for two-phase current signal voltage, T ₁be the first transformation matrix, T ₂it is the second transformation matrix;

Described first transformation matrix is specially:

$T_1=\sqrt{\frac{2}{3}}\left[\begin{array}{cc}1& 0\\ -1/2& \sqrt{3}/2\\ -1/2& -\sqrt{3}/2\end{array}\right]$

Described second transformation matrix is specially:

$T_2=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}\cos \mathrm{\θ}& \cos (\mathrm{\θ}-2\mathrm{\π}/3)& \cos (\mathrm{\θ}+2\mathrm{\π}/3)\\ \sin \mathrm{\θ}& \sin (\mathrm{\θ}-2\mathrm{\π}/3)& \sin (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right]$

Wherein: θ is rotor position angle.

Described step B specifically comprises step:

B1. obtain electric current median according to motor torque and rotor corner, be specially:

$T_e=\frac{1}{w}\underset{i}{\overset{A,B,C}{\mathrm{\Σ}}}{e}_i{i}_i=\frac{\mathrm{EI}}{w}[\frac{3}{2}+\frac{3}{4}(k_a+k_b)+\frac{\sqrt{3}}{2}(k_a-k_b)\sin (2{\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})]$

Wherein: I is electric current median, T _efor motor torque, E is the equivalent voltage between rotor, and w is rotor angle frequency, k _aand k _bbe respectively the measure error of A phase and B phase current of electric and the ratio of actual current value, θ _efor rotor corner;

B2. obtain three-phase adjustment electric current according to electric current median, be specially:

$\left\{\begin{array}{c}{i}_a=I(1+k_a)\sin {\mathrm{\θ}}_e\\ i_b=I(1+k_b)\sin ({\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})\\ i_c=I[\sin ({\mathrm{\θ}}_e+\frac{2}{3}\mathrm{\π})-k_a\sin {\mathrm{\θ}}_e-k_b\sin ({\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})]\end{array}\right.$

Wherein: i _a, i _band i _cbe respectively the three-phase component of adjustment electric current;

B3. three-phase is adjusted the adjustment electric current that current conversion is two-phase.

Compared with prior art, drive system of the present invention and current parameters adjusting device carry out FEEDBACK CONTROL respectively by motor speed and adjustment electric current to motor control assembly, finally vehicle power is controlled by the mode of mechanical-electric coupling, can adjust motor torque, more accurate to the speeds control of vehicle.

Accompanying drawing explanation

Fig. 1 is the structural representation of control appliance of the present invention;

Fig. 2 is the MATLAB/simulink illustraton of model of control appliance of the present invention;

Fig. 3 is the MATLAB/simulink illustraton of model of motor control module;

Fig. 4 is the MATLAB/simulink illustraton of model of drive system;

Wherein: 1, motor control assembly, 2, current parameters adjusting device, 3, drive system, 11, control strategy module, 12, space vector modulation module, 13, inverter module, 14, motor body module, 31, rotor, 32, armature spindle, 33, differential input shaft is subtracted, 34, subtract differential mechanism jack shaft, 35, subtract differential output shaft, 36, discrete left half axle, 37, discrete right axle shaft, 38, revolver, 39, rightly to take turns.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.The present embodiment is implemented premised on technical solution of the present invention, give detailed execution mode and concrete operating process, but protection scope of the present invention is not limited to following embodiment.

A kind of pure electric vehicle power drive system mechanical-electric coupling control appliance, as depicted in figs. 1 and 2, comprising:

Motor control assembly 1, for according to the torque of target torque output motor, rotor corner and current of electric, target torque is wherein sent by pedal by driver;

Drive system 3, is connected with motor control assembly 1, for obtaining motor speed according to motor torque, and this motor speed is sent to motor control assembly 1 FEEDBACK CONTROL motor torque;

Current parameters adjusting device 2, is connected with motor control assembly 1, for generating adjustment electric current according to motor torque, rotor corner and current of electric, and adjustment electric current is sent to motor control assembly 1 feedback regulation motor torque.

As shown in Figure 3, motor control assembly 1 comprises:

Control strategy module 11, receiving target torque, and by maximum torque per ampere control method, target torque is converted to two-phase current signal;

Space vector modulation module 12, is connected with control strategy module 11 and current parameters adjusting device 2 respectively, two-phase current signal and adjustment electric current is integrated and is modulated to two phase voltages;

Inverter module 13, is connected with space vector modulation module 12 and transfer system 3 respectively, for generating current of electric, motor torque and rotor corner according to motor speed and two phase voltages.

In the present embodiment, motor control assembly 1 also comprises motor body module 14, is connected with inverter module 13 and transfer system 3 respectively, for driving transmission system 3, in addition in the present embodiment rotor corner actual by motor body module 14 according to current of electric, motor torque, and the initial corner of rotor provides.

As shown in Figure 4, drive system 3 adopts power train mass concentration-distributed model, comprise connect successively rotor 31, armature spindle 32, subtract differential mechanism, discrete axle group and tire sets.

Subtract differential mechanism comprise connect successively subtract differential input shaft 33, subtract differential mechanism jack shaft 34 and subtract differential output shaft 35.

Discrete axle group comprises discrete left half axle 36 and discrete right axle shaft 37, and tire sets comprises revolver 38 and rightly takes turns 39, one end of discrete left half axle 36 and discrete right axle shaft 37 all with subtract differential mechanism and be connected, the other end is respectively with revolver 38 with rightly take turns 39 and be connected.

The impact of the mesh stiffness in gear drive process, backlash, semiaxis flexibility is taken into full account in the MATLAB/simulink model process of establishing of drive system 3, because lumped-mass model only has higher precision to vibrational system low-frequency range, in order to reflect the impact of the non-linear factor such as motor and gap on power drive system twisting vibration better, set up the semiaxis distributed mass model of discretization; Wheel 38 and right wheel in 39 modeling process ignore Tire nonlinearity characteristic, and car load equivalent inertia are directly added to wheel 38 and rightly take turns the equivalent simulation 39 carcasses carrying out drive train power and car load and move.

Consider that the drive system of semiaxis flexibility concentrates-distributed mass model, abundanter dynamic phenomena can be reflected in time domain, also can reflect the impact of the non-linear factors such as gap on drive system height order frequency domain response characteristic on frequency domain.Contribute to the longitudinal high frequency torsional vibration problem solving the existence of centralized driving driving system for electric vehicles further.

A control method for pure electric vehicle power drive system mechanical-electric coupling control appliance, comprises step:

A. motor control assembly 1 receiving target torque, motor torque, rotor corner and current of electric is generated according to target torque, and motor torque is sent to drive system 3, motor torque, rotor corner and current of electric are all sent to current parameters adjusting device 2;

B. current parameters adjusting device 2 generates adjustment electric current according to motor torque, rotor corner and current of electric, and adjustment electric current is sent to motor control assembly 1 feedback regulation motor torque;

C. drive system 3 obtains motor speed according to motor torque, and this motor speed is sent to motor control assembly 1 FEEDBACK CONTROL motor torque through gain process back.

Specifically step is comprised under the participation that steps A controls at current of electric and motor rotate speed feedback:

A1. control strategy module 11 receiving target torque, and by maximum torque per ampere control method, target torque is converted to two-phase current signal;

A2. space vector modulation module 12 receives two-phase current signal and adjustment electric current, two-phase current signal and adjustment electric current is integrated and is modulated to two phase voltages, and this two phase voltage is sent to inverter module 13, specifically comprise step:

A21. space vector modulation module 12 receives two-phase current signal and adjustment electric current;

A22. two-phase current signal voltage is obtained after two-phase current signal and the superposition of adjustment electric current;

A23. the conversion between two-phase and three-phase signal carried out to two-phase current signal voltage and obtain two phase voltages after processing, and this two phase voltage is sent to inverter module 13, wherein the process that two-phase current signal voltage converts and processes being specially:

U ₂＝U ₁·T ₁·T ₂

Wherein: U ₂be two phase voltages, U ₁for two-phase current signal voltage, T ₁be the first transformation matrix, T ₂it is the second transformation matrix;

First transformation matrix is specially:

$T_1=\sqrt{\frac{2}{3}}\left[\begin{array}{cc}1& 0\\ -1/2& \sqrt{3}/2\\ -1/2& -\sqrt{3}/2\end{array}\right]$

Second transformation matrix is specially:

$T_2=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}\cos \mathrm{\θ}& \cos (\mathrm{\θ}-2\mathrm{\π}/3)& \cos (\mathrm{\θ}+2\mathrm{\π}/3)\\ \sin \mathrm{\θ}& \sin (\mathrm{\θ}-2\mathrm{\π}/3)& \sin (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right]$

Wherein: θ is rotor position angle.

Concrete, two-phase current signal voltage U ₁be set to u _α, u _β, the voltage namely under coordinate system α β, is specially:

$\left\{\begin{array}{c}{u}_{\mathrm{\α}}=R_S{i}_{\mathrm{\α}}+L_{\mathrm{\α}}p{i}_{\mathrm{\α}}+L_{\mathrm{\α\β}}p{i}_{\mathrm{\β}}-{\mathrm{w\ψ}}_f\sin \mathrm{\θ}\\ u_{\mathrm{\β}}=R_S{i}_{\mathrm{\β}}+L_{\mathrm{\β}}p{i}_{\mathrm{\β}}+L_{\mathrm{\α\β}}p{i}_{\mathrm{\α}}-{\mathrm{w\ψ}}_f\cos \mathrm{\θ}\end{array}\right.$

Wherein: R _sfor stator equivalent resistance, i _αand i _βbe respectively the α of stator current vector, beta-axis component, L _αand L _βbe respectively the α of inductance, beta-axis component, L _{α β}for the mutual inductance between rotor, p is differential operator, ψ _αand ψ _βbe respectively the stator magnetic linkage of α, β axle, w is rotor angle frequency.

A3. inverter module 13 generates current of electric, motor torque and rotor corner according to motor speed and two phase voltages, and current of electric and rotor corner are sent to current parameters adjusting device 2, motor torque is sent to respectively current parameters adjusting device 2 and drive system 3.

In step B, current parameters adjusting device 2 can arrange the ratio of biased error and actual current amplitude, analyze biased error in current detecting process to the impact of power drive system twisting vibration, the response of power train when the frequency of the harmonic torque that Main Analysis biased error is introduced is each rank natural frequency; Also current gain error can be set, analyze gain error in current detecting process to the impact of power drive system torsional oscillation, the response of power train when the frequency of the harmonic torque that Main Analysis error is introduced is power train each rank natural frequency.

When under current detecting gain error, detailed process comprises step:

B1. obtain electric current median according to motor torque and rotor corner, be specially:

$T_e=\frac{1}{w}\underset{i}{\overset{A,B,C}{\mathrm{\Σ}}}{e}_i{i}_i=\frac{\mathrm{EI}}{w}[\frac{3}{2}+\frac{3}{4}(k_a+k_b)+\frac{\sqrt{3}}{2}(k_a-k_b)\sin (2{\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})]$

Wherein: I is electric current median, T _efor motor torque, E is the equivalent voltage between rotor, and w is rotor angle frequency, k _aand k _bbe respectively the measure error of A phase and B phase current of electric and the ratio of actual current value, θ _efor rotor corner;

B2. obtain three-phase adjustment electric current according to electric current median, be specially:

$\left\{\begin{array}{c}{i}_a=I(1+k_a)\sin {\mathrm{\θ}}_e\\ i_b=I(1+k_b)\sin ({\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})\\ i_c=I[\sin ({\mathrm{\θ}}_e+\frac{2}{3}\mathrm{\π})-k_a\sin {\mathrm{\θ}}_e-k_b\sin ({\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})]\end{array}\right.$

Wherein: i _a, i _band i _cbe respectively the three-phase component of adjustment electric current;

B3. three-phase is adjusted the adjustment electric current that current conversion is two-phase.

When gear is under current detecting biased error, be specially:

Motor torque rotor corner is substituted into following formula:

$T_e=\frac{1}{w_r}\underset{i}{\overset{A,B,C}{\mathrm{\Σ}}}{e}_i{i}_i=\frac{\mathrm{EI}}{w_r}\{\frac{3}{2}+\sqrt{3}[{\mathrm{\Δ}}_a\cos ({\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})-{\mathrm{\Δ}}_b\cos {\mathrm{\θ}}_e\left]\right\}$

Wherein: Δ _aand Δ _bbe respectively the ratio of A phase and B phase current biased error and actual current value; Three-phase adjustment electric current is obtained again according to electric current median:

$\left\{\begin{array}{c}{i}_a=I(\sin {\mathrm{\θ}}_e+{\mathrm{\Δ}}_a)\\ i_b=I(\sin {\mathrm{\θ}}_e+{\mathrm{\Δ}}_b)\\ i_c=I[(\sin {\mathrm{\θ}}_e+\frac{2}{3}\mathrm{\π})-({\mathrm{\Δ}}_a+{\mathrm{\Δ}}_b)]\end{array}\right.$

Finally three-phase is adjusted the adjustment electric current that current conversion is two-phase.

Similar also has phase deviation, the interference of constant current composition etc., does not repeat.

Claims (10)

1. a pure electric vehicle power drive system mechanical-electric coupling control appliance, is characterized in that, comprising:

Motor control assembly (1), for according to the torque of target torque output motor, rotor corner and current of electric;

Drive system (3), is connected with motor control assembly (1), for obtaining motor speed according to motor torque, and this motor speed is sent to motor control assembly (1) FEEDBACK CONTROL motor torque;

Current parameters adjusting device (2), be connected with motor control assembly (1), for generating adjustment electric current according to motor torque, rotor corner and current of electric, and adjustment electric current is sent to motor control assembly (1) feedback regulation motor torque.

2. a kind of pure electric vehicle power drive system mechanical-electric coupling control appliance according to claim 1, it is characterized in that, described motor control assembly (1) comprising:

Control strategy module (11), receiving target torque, and by maximum torque per ampere control method, target torque is converted to two-phase current signal;

Space vector modulation module (12), is connected with control strategy module (11) and current parameters adjusting device (2) respectively, two-phase current signal and adjustment electric current is integrated and is modulated to two phase voltages;

Inverter module (13), is connected with space vector modulation module (12) and transfer system (3) respectively, for generating current of electric, motor torque and rotor corner according to motor speed and two phase voltages.

3. a kind of pure electric vehicle power drive system mechanical-electric coupling control appliance according to claim 1, it is characterized in that, described drive system (3) comprise connect successively rotor (31), armature spindle (32), subtract differential mechanism, discrete axle group and tire sets.

4. a kind of pure electric vehicle power drive system mechanical-electric coupling control appliance according to claim 3, it is characterized in that, described in subtract differential mechanism comprise connect successively subtract differential input shaft (33), subtract differential mechanism jack shaft (34) and subtract differential output shaft (35).

5. a kind of pure electric vehicle power drive system mechanical-electric coupling control appliance according to claim 3, it is characterized in that, described discrete axle group comprises discrete left half axle (36) and discrete right axle shaft (37), described tire sets comprises revolver (38) and rightly to take turns (39), one end of described discrete left half axle (36) and discrete right axle shaft (37) all with subtract differential mechanism and be connected, the other end is connected with revolver (38) and right take turns (39) respectively.

6. a control method for pure electric vehicle power drive system mechanical-electric coupling control appliance as claimed in claim 2, is characterized in that, comprise step:

A. motor control assembly (1) receiving target torque, motor torque, rotor corner and current of electric is generated according to target torque, and motor torque is sent to drive system (3), motor torque, rotor corner and current of electric are all sent to current parameters adjusting device (2);

B. current parameters adjusting device (2) generates adjustment electric current according to motor torque, rotor corner and current of electric, and adjustment electric current is sent to motor control assembly (1) feedback regulation motor torque;

C. drive system (3) obtains motor speed according to motor torque, and this motor speed is sent to motor control assembly (1) FEEDBACK CONTROL motor torque.

7. a kind of pure electric vehicle power drive system mechanical-electric coupling control method according to claim 6, is characterized in that, specifically comprises step under the participation that described steps A controls at current of electric and motor rotate speed feedback:

A1. control strategy module (11) receiving target torque, and by maximum torque per ampere control method, target torque is converted to two-phase current signal;

A2. space vector modulation module (12) receives two-phase current signal and adjustment electric current, two-phase current signal and adjustment electric current is integrated and is modulated to two phase voltages, and this two phase voltage is sent to inverter module (13);

A3. inverter module (13) generates current of electric, motor torque and rotor corner according to motor speed and two phase voltages, and current of electric and rotor corner are sent to current parameters adjusting device (2), motor torque is sent to respectively current parameters adjusting device (2) and drive system (3).

8. a kind of pure electric vehicle power drive system mechanical-electric coupling control method according to claim 7, it is characterized in that, described steps A 2 specifically comprises step:

A21. space vector modulation module (12) receives two-phase current signal and adjustment electric current;

A22. two-phase current signal voltage is obtained after two-phase current signal and the superposition of adjustment electric current;

A23. obtain two phase voltages after two-phase current signal voltage being converted and processed, and this two phase voltage is sent to inverter module (13).

9. a kind of pure electric vehicle power drive system mechanical-electric coupling control method according to claim 8, is characterized in that, be specially in described steps A 23 to the process that two-phase current signal voltage converts and processes:

U ₂＝U ₁·T ₁·T ₂

Wherein: U ₂be two phase voltages, U ₁for two-phase current signal voltage, T ₁be the first transformation matrix, T ₂it is the second transformation matrix;

Described first transformation matrix is specially:

$T_1=\sqrt{\frac{2}{3}}\left[\begin{array}{cc}1& 0\\ -1/2& \sqrt{3}/2\\ -1/2& -\sqrt{3}/2\end{array}\right]$

Described second transformation matrix is specially:

$T_2=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}\cos \mathrm{\θ}& \cos (\mathrm{\θ}-2\mathrm{\π}/3)& \cos (\mathrm{\θ}+2\mathrm{\π}/3)\\ \sin \mathrm{\θ}& \sin (\mathrm{\θ}-2\mathrm{\π}/3)& \sin (\mathrm{\θ}+2\mathrm{\π}/3)\end{array}\right]$

Wherein: θ is rotor position angle.

10. a kind of pure electric vehicle power drive system mechanical-electric coupling control method according to claim 6, it is characterized in that, described step B specifically comprises step:

B1. obtain electric current median according to motor torque and rotor corner, be specially:

$T_e=\frac{1}{w}\underset{i}{\overset{A,B,C}{\mathrm{\Σ}}}{e}_i{i}_i=\frac{\mathrm{EI}}{w}[\frac{3}{2}+\frac{3}{4}(k_a+k_b)+\frac{\sqrt{3}}{2}(k_a-k_b)\sin (2{\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})]$

Wherein: I is electric current median, T _efor motor torque, E is the equivalent voltage between rotor, and w is rotor angle frequency, k _aand k _bbe respectively the measure error of A phase and B phase current of electric and the ratio of actual current value, θ _efor rotor corner;

B2. obtain three-phase adjustment electric current according to electric current median, be specially:

$\left\{\begin{array}{c}{i}_a=I(1+k_a)\sin {\mathrm{\θ}}_e\\ i_b=I(1+k_b)\sin ({\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})\\ i_c=I[\sin ({\mathrm{\θ}}_e+\frac{2}{3}\mathrm{\π})-k_a\sin {\mathrm{\θ}}_e-k_b\sin ({\mathrm{\θ}}_e-\frac{2}{3}\mathrm{\π})]\end{array}\right.$

Wherein: i _a, i _band i _cbe respectively the three-phase component of adjustment electric current;

B3. three-phase is adjusted the adjustment electric current that current conversion is two-phase.