CN109591615B

CN109591615B - Active heat control method of electric automobile controller and application system thereof

Info

Publication number: CN109591615B
Application number: CN201811307112.6A
Authority: CN
Inventors: 应展烽; 张伟; 张旭东; 姜鑫; 钟震
Original assignee: Nanjing University of Science and Technology
Current assignee: Nanjing University of Science and Technology
Priority date: 2018-11-05
Filing date: 2018-11-05
Publication date: 2022-03-25
Anticipated expiration: 2038-11-05
Also published as: CN109591615A

Abstract

The invention discloses an active thermal control method for an electric vehicle controller, comprising a fuzzy controller, a motor vector control system, a DSP28035 processor, a drive circuit, a temperature acquisition circuit, a current acquisition circuit, a voltage acquisition circuit, SCI communication, a host computer, Three-phase inverter, the output of the temperature detection circuit is connected to the AD pin of the DSP28035 processor. The DSP28035 processor is connected to the host computer through SCI communication. Through the temperature acquisition circuit, the DSP28035 processor measures the actual temperature of the controller in real time, and The real-time temperature value is transmitted to the controller temperature closed-loop fuzzy controller based on software, and the reasonable maximum limit value of the torque current in the motor vector control system is calculated, so as to realize the active thermal management of the controller temperature. The invention solves the problems that the temperature protection of the existing electric vehicle controller is too conservative and the load-carrying capacity of the electric vehicle is low, effectively reduces the failure rate of the electric vehicle controller caused by overheating, and simultaneously improves the load-carrying capacity of the electric vehicle.

Description

Active heat control method of electric automobile controller and application system thereof

Technical Field

The invention belongs to the control technology of an electric motor of an automobile, and particularly relates to an active heat control method of a controller and an application system thereof.

Background

With the development of power electronic technology, power devices such as MOSFET and IGBT are widely applied in the field of electric vehicle control. The packaging size of the motor controller is gradually reduced, but the requirements on the power level and the heat flux density are gradually improved, and various failure faults caused by high temperature are easy to occur, so that the service life and the reliability of the motor controller are influenced. Therefore, it is necessary to acquire the operating temperature of the controller in real time to realize corresponding active thermal control and overheating protection, thereby improving the operational reliability and better driving experience.

Traditional industrial motor is different, needs the motor can improve fast in the short time and exert oneself under the operating mode such as climbing, obstacle crossing to obtain good driving experience, it is big to need electric automobile induction motor to have starting torque promptly, and the instantaneous ability of exerting oneself, simultaneously, also requires controller and motor to have higher power density grade. However, the large torque operation requires the electric automobile controller to output larger current, so that the temperature of the motor rises rapidly, and the power device in the controller generates heat seriously, thereby bringing about potential safety hazard for the reliable operation of the motor. In order to prevent the motor from being damaged due to the overhigh temperature of the motor and the power device in the controller from being thermally broken down due to the overhigh temperature, a temperature protection point is usually set in the conventional thermal protection of the controller of the electric automobile, and once the temperature obtained by feedback exceeds the set value, the current is reduced by half to operate so as to prevent the motor from being thermally overloaded. However, the existing temperature protection measures are usually passive protection, and the protection for the temperature is conservative. In the temperature protection of the existing controller, probes of a temperature sensor are all placed on the inner wall of a shell of the controller and are not directly placed on a power board with the most serious heat release, so that the measured temperature cannot accurately reflect the shell temperature of the current power device during working, and the power device in an electric automobile controller cannot be subjected to over-temperature protection accurately and quickly. Meanwhile, the traditional PI controller is adopted in the existing temperature closed loop, the requirement of the electric automobile for outputting large torque in an obstacle crossing instant mode cannot be met, and once the temperature of the controller exceeds a threshold value, the response speed of the traditional PI controller is low, so that the temperature of the controller of the electric automobile cannot be completely guaranteed to be rapidly reduced below the threshold value, and potential safety hazards are brought to reliable operation of the controller of the electric automobile.

Disclosure of Invention

The invention aims to provide an active thermal control method of a controller and an application system thereof, and solves the problem that the output capacity of a power device is over conservative in the thermal protection method of the conventional electric automobile controller.

The technical solution for realizing the purpose of the invention is as follows: an active heat control method of an electric automobile controller comprises the following steps:

step 1, a DSP (digital signal processor) outputs 6 paths of PWM (pulse-width modulation) voltage driving signals according to signals fed back by a temperature acquisition circuit, a current acquisition circuit and a voltage acquisition circuit in real time, and the driving signals are subjected to power amplification through a driving circuit and output to a three-phase inverter;

step 2, Clark conversion and Park conversion in the motor vector control system convert the two-phase stator currents ia and ib of the asynchronous motor into currents iq and id under a two-phase rotating coordinate system; the flux linkage observer calculates a magnetic field orientation angle theta according to iq, id and the rotating speed n of the asynchronous motor; calculating switching time Ta, Tb and Tc of U, V, W three-phase upper and lower bridge arms in the three-phase inverter according to an SVPWM algorithm, and controlling the three-phase inverter to output three-phase currents ia, ib and ic to drive the asynchronous motor;

and 3, calculating a limiting value L _ lim of the q-axis current by the fuzzy controller according to the temperature of the three-phase inverter obtained through feedback, and limiting the q-axis current closed loop.

In the step 3, the input of the fuzzy controller is the real-time temperature value of the three-phase inverter acquired by the temperature acquisition circuit, the error amount E and the error change rate EC are obtained by comparison with the set temperature threshold, the output is judged by the fuzzy logic algorithm, and the maximum limit value I _ lim of the torque current is obtained under the current error amount and the error change rate.

A system applying an active heat control method of an electric automobile controller comprises a fuzzy controller, a motor vector control system, a DSP (digital signal processor), a driving circuit, a temperature acquisition circuit, a current acquisition circuit, a voltage acquisition circuit, SCI (communication interface) communication and an upper computer; the motor vector control system comprises an asynchronous motor, a three-phase inverter, an SVPWM algorithm, a q-axis current closed-loop integrator, a rotating speed closed-loop integrator, a flux linkage observer, Park transformation, Clark transformation and a d-axis current closed-loop integrator; the motor vector control system comprises an asynchronous motor, a three-phase inverter, an SVPWM algorithm, a q-axis current closed-loop integrator, a rotating speed closed-loop integrator, a flux linkage observer, Park transformation, Clark transformation, a d-axis current closed-loop integrator and an amplitude limiting module; the input of the Clark conversion is connected with two-phase currents ia and ib of the asynchronous motor, and the output of the Clark conversion is connected with Park conversion; the input of the flux linkage observer is respectively connected with the asynchronous motor and Park conversion, and the output of the flux linkage observer is connected with the Park conversion and SVPWM algorithm; the input of the d-axis current closed-loop integrator is connected with a difference signal of an exciting current given value id _ ref and an exciting current feedback value id, and the output is connected to the SVPWM algorithm; the input of the rotating speed closed-loop integrator is connected with a difference value signal of a given value n _ ref and a rotating speed feedback value n of the rotating speed, and the output of the rotating speed closed-loop integrator is connected with the amplitude limiting module; the input of the q-axis current closed-loop integrator is connected with a difference signal of a torque current reference value iq _ ref and a torque current feedback value iq, and the output is connected to the SVPWM algorithm; the SVPWM algorithm is respectively connected with the d-axis current closed-loop integrator, the q-axis current closed-loop integrator and the asynchronous motor, and the output of the SVPWM algorithm is connected to the three-phase inverter; the output of the three-phase inverter is connected to the asynchronous motor; the input of the fuzzy controller is connected with the three-phase inverter, and the output of the fuzzy controller is connected with the amplitude limiting module.

The temperature acquisition circuit, the current acquisition circuit and the voltage acquisition circuit are respectively connected with an AD pin of the DSP; SCI communication is connected with an SCI communication pin of the DSP processor; the temperature acquisition circuit is used for respectively acquiring the ambient temperature, the shell temperature of the whole controller and the U, V, W three-phase MOSFET shell temperature of the three-phase inverter, performing analog-to-digital conversion on the acquired temperature to generate a digital signal and sending the generated digital signal to the DSP processor; the current acquisition circuit is used for respectively acquiring U, V, W three-phase currents of the asynchronous motor, performing analog-to-digital conversion on the acquired currents through the current acquisition circuit and sending generated digital signals to the DSP; the voltage acquisition circuit acquires direct-current power supply voltages at two ends of the three-phase inverter, performs analog-to-digital conversion on the acquired voltages, and sends generated digital signals to the DSP; the DSP processor processes the acquired temperature, current and voltage digital signals, converts the signals into actual values, and transmits the acquired signals to a background upper computer through SCI communication.

Compared with the prior art, the invention has the remarkable advantages that:

(1) compared with the traditional passive thermal protection method, the power device can obviously improve the output capability of the power device, the capability of instantly outputting large torque and the utilization rate of energy.

(2) The temperature fluctuation of the power device in the controller can be effectively smoothed, and the device failure probability caused by repeated impact of thermal stress borne by the power device in repeated heating and cooling processes is reduced.

(3) The adopted control algorithm has strong anti-interference capability and high response speed, does not need a clear model of a controlled object, and has stronger robustness on the change of system parameters.

Drawings

Fig. 1 is a schematic structural diagram of a motor vector control system according to the present invention.

FIG. 2 is a diagram illustrating a hardware system structure according to the present invention.

Fig. 3 is a schematic structural diagram of a temperature detection circuit according to the present invention.

Fig. 4 is a schematic structural diagram of a current detection circuit according to the present invention.

Fig. 5 is a schematic diagram of a voltage detection circuit according to the present invention.

Fig. 6 is a schematic diagram of a three-phase inverter topology of the present invention.

Fig. 7 is a schematic diagram of a driving circuit structure according to the present invention.

Detailed Description

The present invention is described in further detail below with reference to the attached drawing figures.

The invention discloses an active heat control method of an electric automobile controller, which comprises the following steps:

step 1, the DSP28035 processor 3 outputs 6 PWM voltage drive signals according to the real-time feedback signals of the temperature acquisition circuit 5, the current acquisition circuit 6 and the voltage acquisition circuit 7, and the drive signals are amplified in power by the drive circuit 4 and output to the three-phase inverter 22;

step 2, Clark conversion 28 and Park conversion 27 in the motor vector control system 2 convert the two-phase stator currents ia and ib of the asynchronous motor 21 into currents iq and id under a two-phase rotating coordinate system; the flux linkage observer 26 calculates a magnetic field orientation angle theta according to iq, id and the rotating speed n of the asynchronous motor 21; calculating switching time Ta, Tb and Tc of U, V, W three-phase upper and lower bridge arms in the three-phase inverter 22 according to the SVPWM algorithm 23, and controlling the three-phase inverter 22 to output three-phase currents ia, ib and ic to drive the asynchronous motor 21;

and 3, calculating a limiting value L _ lim of the q-axis current by the fuzzy controller 1 according to the temperature of the three-phase inverter 22 obtained through feedback, and limiting the q-axis current closed loop.

With reference to fig. 1 to 6, a system applying an active thermal control method of an electric vehicle controller is characterized in that: the system comprises a fuzzy controller 1, a motor vector control system 2, a DSP28035 processor 3, a drive circuit 4, a temperature acquisition circuit 5, a current acquisition circuit 6, a voltage acquisition circuit 7, SCI communication 8 and an upper computer 9.

As shown in fig. 1, the motor vector control system 2 includes an asynchronous motor 21, a three-phase inverter 22, an SVPWM algorithm 23, a q-axis current closed-loop integrator 24, a rotational speed closed-loop integrator 25, a flux linkage observer 26, a Park transformation 27, a Clark transformation 28, a d-axis current closed-loop integrator 29, and a limiting module. The input of the Clark conversion 28 is connected with the two-phase currents ia and ib of the asynchronous motor 21, and the output is connected with the Park conversion 27; the input of the flux linkage observer 26 is respectively connected with the asynchronous motor 21 and the Park transformation 27, and the output is connected to the Park transformation 27 and the SVPWM algorithm 23; the input of the d-axis current closed-loop integrator 29 is connected with a difference signal of an exciting current given value id _ ref and an exciting current feedback value id, and the output is connected to the SVPWM algorithm 23; the input of the rotating speed closed-loop integrator 25 is connected with a difference value signal of a given value n _ ref of the rotating speed and a rotating speed feedback value n, and the output is connected with an amplitude limiting module; the input of the q-axis current closed-loop integrator 24 is connected with a difference signal of a torque current reference value iq _ ref and a torque current feedback value iq, and the output is connected to the SVPWM algorithm 23; the SVPWM algorithm 23 is respectively connected with a d-axis current closed-loop integrator 29, a q-axis current closed-loop integrator 24 and the asynchronous motor 21, and the output of the SVPWM algorithm is connected to the three-phase inverter 22; the output of the three-phase inverter 22 is connected to the asynchronous machine 22; the input of the fuzzy controller 1 is connected with the three-phase inverter 22, and the output is connected with the amplitude limiting module.

Specifically, the inputs of the Clark transformation 28 are two-phase stator currents ia and ib of the asynchronous motor 21, and the two-phase stator currents ia and ib are converted into stator currents ial and ibe under a two-phase stationary coordinate system, the stator currents under the stationary coordinate system are converted into a torque current iq and an excitation current id under a space two-phase rotating coordinate system through the Park transformation 27, and the outputs of the Park transformation 27 are sent to the flux linkage observer 26. The input of the flux linkage observer 26 is a torque current iq, an excitation current id and a rotation speed n fed back by the asynchronous motor 21, and the output magnetic field orientation angle θ is calculated and fed back to the SVPWM algorithm 23 and the Park transformation 27 in real time. The given excitation current reference id _ ref is compared with the excitation current id obtained by real-time calculation through Park conversion 27, the difference value of the two is output to a d-axis current closed-loop integrator 29, and a reference d-axis voltage Ud of the SVPWM algorithm 23 is output through the d-axis current closed-loop integrator 29. Meanwhile, a given rotating speed reference value n _ ref is compared with a rotating speed n signal fed back by the asynchronous motor 21, the difference value of the two is output to the rotating speed closed-loop integrator 25, and the output of the rotating speed closed-loop integrator 25 is subjected to amplitude limiting to obtain a torque current reference iq _ ref. Furthermore, the clipping value is obtained from the output of the fuzzy controller 1, and the input of the fuzzy controller 1 is the real-time temperature feedback T _ fd connected to the three-phase inverter 22. The obtained torque current reference iq _ ref is compared with the torque current iq obtained by real-time calculation through Park conversion 27, a difference value is output to a q-axis current closed-loop integrator 24, and a reference q-axis voltage Uq of the SVPWM algorithm 23 is obtained through output of the q-axis current closed-loop integrator. Finally, the SVPWM algorithm calculates the conduction switching time Ta, Tb, Tc of the upper and lower arms of U, V, W three phases in the three-phase inverter 22 according to the dc bus voltage UDC, the torque voltage Uq, and the excitation voltage Ud fed back by the asynchronous motor 21, so as to drive the three-phase inverter 22 to output appropriate three-phase currents ia, ib, and ic to the asynchronous motor 21.

The temperature fuzzy controller 1 is a two-dimensional fuzzy controller realized based on a software form and is combined with the asynchronous motor vector control system 2, and a fuzzy logic algorithm in the temperature fuzzy controller 1 adopts a table look-up method which can be obtained by off-line calculation, so that the processing speed of the processor can be greatly improved.

The input of the fuzzy controller 1 is the real-time temperature value of the three-phase inverter 22 collected by the temperature collecting circuit 5, the error quantity E and the error change rate EC are obtained by comparing with the set temperature threshold value, and the output is judged by a fuzzy logic algorithm:

when the comparison result shows that the actual temperature of the three-phase inverter 22 is greater than the set temperature threshold, the fuzzy controller 1 reduces the limit value I _ lim of the torque current;

when the actual temperature of the three-phase inverter 22 is less than the set temperature threshold, the fuzzy controller 1 will increase the limit value I _ lim of the torque current;

when the actual temperature of the three-phase inverter 22 is equal to the set temperature threshold, the fuzzy controller 1 keeps the limit value I _ lim of the torque current unchanged.

Specifically, the temperature acquisition circuit 5, the current acquisition circuit 6 and the voltage acquisition circuit 7 are respectively connected with an AD pin of the DSP28035 processor 3; SCI communication 8 is connected with the SCI communication pin of the DSP28035 processor 3; the temperature acquisition circuit 5 respectively acquires the ambient temperature, the shell temperature of the whole controller and the U, V, W three-phase MOSFET shell temperature of the three-phase inverter 22, performs analog-to-digital conversion on the acquired temperatures to generate digital signals, and sends the generated digital signals to the DSP28035 processor 3; the current acquisition circuit 6 is used for respectively acquiring U, V, W three-phase currents of the asynchronous motor 21, performing analog-to-digital conversion on the acquired currents through the current acquisition circuit 6 and sending generated digital signals to the DSP28035 processor 3; the voltage acquisition circuit 7 acquires direct-current power supply voltages at two ends of the three-phase inverter 22, performs analog-to-digital conversion on the acquired voltages, and sends generated digital signals to the DSP28035 processor 3; the DSP28035 processor 3 processes the acquired temperature, current and voltage digital signals, converts the signals into actual values, and transmits the acquired signals to the background upper computer 9 through SCI communication 8.

Furthermore, the temperature acquisition circuit 5 sends the acquired temperature of the three-phase inverter 22 to the DSP28035 processor 3, and the fuzzy temperature controller 1 determines and outputs a torque current limit value suitable for the motor vector control system 2 at that time.

As shown in fig. 3, the temperature acquisition circuit 5 includes a 3.3V power supply 53, a first voltage divider 54, a first filter circuit 52, a first overvoltage protection circuit 51, and a thermistor 228. The thermistor 228 is connected in series with the first voltage-dividing resistor 54, one end of the thermistor is grounded, the other end of the thermistor 228 is connected with the first voltage-dividing resistor 54, the other end of the thermistor 228, which is not grounded, is connected to the first filter circuit 52, and the sampling voltage value input to the ADCINB0 pin of the digital processor 3 of the DSP28035 is filtered into a stable voltage value through the first filter circuit 52, so that the sampling accuracy is improved. The filtered voltage signal is connected to an ADCINB0 pin of the DSP28035 digital processor 3 through a first overvoltage protection circuit 51, and the first overvoltage protection circuit 51 is used for ensuring that the voltage input to the ADCINB0 pin of the DSP28035 digital processor 3 is not more than 3.3V, so as to protect the normal operation of the processor.

As shown in fig. 4, the current collecting circuit 6 includes a current sensor 61, a second filter circuit 62, and a second overvoltage protection circuit 63. The current sensor 61 outputs a corresponding voltage digital signal according to the current value of the collected object, the output is connected to the second filter circuit 62, and the voltage value of the ADCINA0 pin input to the DSP28035 digital processor 3 is filtered into a stable voltage value through the second filter circuit 62, so that the sampling accuracy is improved. The filtered voltage signal is connected to an ADCINA0 pin of the DSP28035 digital processor 3 through a second overvoltage protection circuit 63, and the second overvoltage protection circuit 63 is used for ensuring that the voltage input to the ADCINA0 pin of the DSP28035 digital processor 3 is not more than 3.3V, so as to protect the normal operation of the processor.

As shown in fig. 5, the voltage acquisition circuit 7 includes a second voltage dividing resistor 71, a third voltage dividing resistor 74, a third filter circuit 72, and a third overvoltage protection circuit 73. The second voltage dividing resistor 71 and the third voltage dividing resistor 74 are connected in series, and one end of the third voltage dividing resistor 74 is grounded and the other end is connected to the second voltage dividing resistor 71 and the third filter circuit 72. The third filter circuit 72 filters the level signal across the third voltage dividing resistor 74 into a stable voltage value, thereby improving the sampling accuracy. The filtered voltage signal is connected to an ADCINB1 pin of the DSP28035 digital processor 3 through a third overvoltage protection circuit 73. the third overvoltage protection circuit 73 is used for ensuring that the voltage input to the ADCINB1 pin of the DSP28035 digital processor 3 is not more than 3.3V, thereby protecting the normal operation of the processor.

As shown in fig. 6, the driving circuit 4 mainly includes a 12V power supply 41 and a driving chip 42. The 12V power supply 41 is connected with a VCC pin of the driving chip 42 to supply power to the chip, the input 6 paths of PWM signals PWM1A, PWM1B, PWM2A, PWM2B, PWM3A and PWM3B are connected with an IN pin of the chip, the output 6 paths of PWM signals 1A, 1B, 2A, 2B, 3A and 3B are connected with an HO pin of the chip, and the driving chip 42 amplifies the power of the 6 paths of PWM voltage driving signals output by the DSP28035 processor 3, so that the normal work of the three-phase inverter 22 can be driven.

As shown in fig. 7, the three-phase inverter 22 mainly includes a dc power supply 221, a first MOSFET 222, a second MOSFET 223, a third MOSFET 224, a fourth MOSFET 225, a fifth MOSFET 226, and a sixth MOSFET 227. The drains of the first MOSFET 222, the third MOSFET 224 and the fifth MOSFET 226 are connected to the positive electrode of the direct current power supply 221, the sources of the second MOSFET 223, the fourth MOSFET 225 and the sixth MOSFET 227 are connected to the negative electrode of the direct current power supply 221, the source of the first MOSFET 222 is connected to the drain of the second MOSFET 223 to form a U-phase arm, the source of the third MOSFET 224 is connected to the drain of the fourth MOSFET 225 to form a V-phase arm, and the source of the fifth MOSFET 226 is connected to the drain of the sixth MOSFET 227 to form a V-phase arm. By applying suitable drive signals to the gates of the six MOSFET transistors, three-phase symmetrical voltages can be generated, which drive the operation of the asynchronous motor 21.

Claims

1. an active thermal control method of an electric vehicle controller, is characterized in that, the control method steps are as follows:

Step 1. The DSP processor (3) outputs 6-channel PWM voltage driving signals according to the real-time feedback signals of the temperature acquisition circuit (5), the current acquisition circuit (6), and the voltage acquisition circuit (7). Amplify the power of the driving signal and output it to the three-phase inverter (22);

Step 2. The Clark transformation module (28) and the Park transformation module (27) in the motor vector control system (2) convert the two-phase stator currents ia and ib of the asynchronous motor (21) into the current iq in the two-phase rotating coordinate system , id; the flux linkage observer (26) calculates the magnetic field orientation angle θ according to iq, id and the rotational speed n of the asynchronous motor (21); The switching time Ta, Tb, Tc of the upper and lower bridge arms of the V and W three-phase, the asynchronous motor (21) is driven by controlling the three-phase inverter (22) to output the three-phase currents ia, ib, ic;

Step 3. The fuzzy controller (1) calculates the limit value L_lim of the q-axis current according to the temperature of the three-phase inverter (22) obtained by the feedback, and limits the closed-loop of the q-axis current:

In the step 3, the input of the fuzzy controller (1) is the real-time temperature value of the three-phase inverter (22) collected by the temperature collection circuit (5), and the error amount E is calculated by comparing with the set temperature threshold. And the error rate of change EC, the output is determined by the fuzzy logic algorithm. Under the current error amount and error rate of change, the maximum limit value I_lim of the torque current is determined by the fuzzy logic algorithm:

When the comparison result is that the actual temperature of the three-phase inverter (22) is greater than the set temperature threshold, the fuzzy controller (1) will reduce the limit value I_lim of the torque current;

When the actual temperature of the three-phase inverter (22) is less than the set temperature threshold, the fuzzy controller (1) will increase the limit value I_lim of the torque current;

When the actual temperature of the three-phase inverter (22) is equal to the set temperature threshold, the fuzzy controller (1) keeps the limit value I_lim of the torque current unchanged.

2. The active thermal control method for an electric vehicle controller according to claim 1, characterized in that: the fuzzy controller (1) is a two-dimensional fuzzy controller implemented in a software form, and is combined with a motor vector control system ( 2) Combined.

3 . The active thermal control method for an electric vehicle controller according to claim 1 , wherein the DSP processor ( 3 ) adopts a DSP28035 processor. 4 .

4 . The active thermal control method for an electric vehicle controller according to claim 1 , wherein the fuzzy logic algorithm in the fuzzy controller ( 1 ) adopts a table look-up method and is obtained through offline calculation. 5 .

5. A system for applying the active thermal control method of an electric vehicle controller according to claim 1, characterized in that it comprises a fuzzy controller (1), a motor vector control system (2), a DSP processor (3), a driver Circuit (4), temperature acquisition circuit (5), current acquisition circuit (6), voltage acquisition circuit (7), SCI communication (8), host computer (9); the motor vector control system (2) includes an asynchronous motor (21), three-phase inverter (22), SVPWM algorithm module (23), q-axis current closed-loop integrator (24), rotational speed closed-loop integrator (25), flux linkage observer (26), Park transformation module ( 27), Clark transformation module (28), d-axis current closed-loop integrator (29); the input of the Clark transformation module (28) is connected to the two-phase current ia, ib of the asynchronous motor (21), and the output is connected to the Park transformation module (27) ); the input of the flux linkage observer (26) is connected to the asynchronous motor (21) and the Park transformation module (27) respectively, and the output is connected to the Park transformation module (27) and the SVPWM algorithm module (23); the d-axis current closed-loop integrator The input of (29) is connected to the difference signal of the excitation current given value id_ref and the excitation current feedback value id, and the output is connected to the SVPWM algorithm module (23); the input of the closed-loop integrator (25) and the given value n_ref of the speed It is connected to the difference signal of the speed feedback value n, and the output is connected to the limiting module; the input of the q-axis current closed-loop integrator (24) is connected to the difference signal of the torque current reference value iq_ref and the torque current feedback value iq, and the output is connected to the SVPWM algorithm module (23); the SVPWM algorithm module (23) is respectively connected to the d-axis current closed-loop integrator (29), the q-axis current closed-loop integrator (24) and the asynchronous motor (21), and the output is connected to the three-phase inverter The inverter (22); the output of the three-phase inverter (22) is connected to the asynchronous motor (21); the input of the fuzzy controller (1) is connected to the three-phase inverter (22), and the output is connected to the limiter module;

The temperature acquisition circuit (5), the current acquisition circuit (6), and the voltage acquisition circuit (7) are respectively connected with the AD pins of the DSP processor (3); the SCI communication (8) is connected to the SCI of the DSP processor (3). The communication pins are connected to each other; the temperature acquisition circuit (5) collects the ambient temperature, the case temperature of the entire controller and the MOSFET case temperature of the U, V and W phases of the three-phase inverter (22) respectively, and collects the The collected temperature is subjected to analog-to-digital conversion to generate a digital signal, and the generated digital signal is sent to the DSP processor (3); the current acquisition circuit (6) respectively collects the U, V, and W of the asynchronous motor (21). phase current, the collected current is converted into analog-to-digital through the current collection circuit (6), and the generated digital signal is sent to the DSP processor (3); the voltage collection circuit (7) collects the three-phase inverter ( 22) The DC power supply voltage at both ends, perform analog-to-digital conversion on the collected voltage, and send the generated digital model to the DSP processor (3); the DSP processor (3) analyzes the collected temperature, current, The voltage digital signal is processed, converted into an actual value, and the collected signal is transmitted to the host computer (9) in the background through the SCI communication (8).