Safety state control system for motor control

Abstract

The invention relates to a safety state control system for motor control, and the system comprises a control chip which is used for outputting a pulse width modulation signal; the power supply monitoring chip is used for carrying out safety monitoring on the control chip in real time; the motor parameter detection module is used for collecting motor parameters and converting the motor parameters into corresponding voltage signals; the safety state switching judgment module is used for receiving the pulse width modulation signal, the fault enabling state signal and the voltage signal and generating a control signal according to the received signals; the driving circuit module is used for isolating and amplifying the control signal; and the power conversion module is used for enabling the motor and the safety state control system to enter a corresponding safety state according to the input control signal. After the control chip fails, safety state switching can be reliably carried out according to different working conditions, more accurate safety state control is achieved, the whole vehicle switching is more flexible, and a more reliable safety state is output.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicle motor control, and in particular to a safety state control system for motor control. Background Art

[0002] With the rapid development of my country's new energy vehicle industry, the safety of electric vehicles has gradually attracted more attention. Among them, the functional safety of the main drive motor controller is particularly important. After detecting a functional safety-related fault (such as a control chip fault), the main drive motor controller needs to reliably enter a safe state to prevent violations of safety goals. Functional safety requirements for motor controllers: Enter a safe state after safety fault detection to prevent violations of safety goals. The usual safety states of the main drive motor controller are ASC (Active Short Circuit) and SPO (Six Pack Off), which usually need to be selected and switched according to the motor operating status.

[0003] Controller monitoring requires independent entry into a safe state through an independent monitor; the current mainstream solution is to directly enter ASC, which is simple but will increase the risk of unexpected braking at low speeds.

[0004] A prior Chinese patent application with publication number CN115817379A and invention name "Fault handling system for motor control circuit" generates a safe state switching control signal through two-phase voltage to control the motor control circuit to enter the corresponding safe state, thereby improving the reliability of the whole vehicle and ensuring driving safety. This technical solution can only be detected in the normal state / SPO state, and the phase / line voltage is zero in the ASC state, and the frequency cannot be monitored to switch to SPO. Therefore, it can only be used as a safe state to enter before the fault, and it is impossible to achieve real-time switching of the safe state according to the working conditions in the fault state. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide a safe state control system for motor control to solve the problem that the existing fault handling system cannot switch the safe state in real time according to the changes in working conditions.

[0006] The technical solution to achieve the above purpose is: The present invention provides a safe state control system for motor control, comprising: A control chip for outputting a pulse width modulation signal; A power monitoring chip connected to the control chip, used to monitor the safety of the control chip in real time and output a fault enabling state signal when a fault occurs in the control chip; A motor parameter detection module connected to the motor, used to collect motor parameters and convert them into corresponding voltage signals; A safety state switching judgment module is connected to the control chip, the power monitoring chip and the motor parameter detection module, and is used to receive the pulse width modulation signal output by the control chip, the fault enable state signal output by the power monitoring chip and the voltage signal output by the motor parameter detection module, and generate a control signal according to the received signal; A driving circuit module connected to the safety state switching judgment module, used to isolate and amplify the control signal; The power conversion module connected to the driving circuit module and the motor is used to make the motor and the safety state control system enter a corresponding safety state according to an input control signal.

[0007] A further improvement of the safe state control system of the motor control of the present invention is that the motor parameter detection module includes a phase voltage monitoring module and a phase current monitoring module; The phase voltage monitoring module is connected to the motor, and is used to collect the phase voltage of the motor, and output a level voltage Vf_Vo proportional to the frequency and a level voltage Va_Vo proportional to the amplitude; The phase current monitoring module is connected to the motor, and is used to collect the phase current of the motor, and output a level voltage If_Vo proportional to the frequency and a level voltage Ia_Vo proportional to the amplitude.

[0008] A further improvement of the safety state control system of the motor control of the present invention is that the safety state switching judgment module includes a first AND gate connected to the control chip and the power monitoring chip, a first negation module connected to the power monitoring chip, a first comparator whose in-phase input terminal is connected to the output terminal of the level voltage Vf_Vo proportional to the frequency of the phase voltage monitoring module, a second comparator whose in-phase input terminal is connected to the output terminal of the level voltage Va_Vo proportional to the amplitude of the phase voltage monitoring module, a third comparator whose in-phase input terminal is connected to the output terminal of the level voltage If_Vo proportional to the frequency of the phase current monitoring module, a fourth comparator whose in-phase input terminal is connected to the output terminal of the level voltage Ia_Vo proportional to the amplitude of the phase current monitoring module, a second AND gate connected to the output terminal of the first comparator, a third AND gate connected to the output terminal of the third comparator, a fourth AND gate connected to the output terminals of the second comparator and the fourth comparator, a second negation module connected to the output terminal of the fourth AND gate, an OR gate connected to the output terminals of the second AND gate and the third AND gate, and a fifth AND gate connected to the output terminals of the first negation module and the OR gate; The inverting input terminal of the first comparator is a first preset reference voltage Vr1; The non-inverting input terminal of the second comparator is a second preset reference voltage Vr2; The inverting input terminal of the third comparator is a third preset reference voltage Vr3; The inverting input terminal of the fourth comparator is a fourth preset reference voltage Vr4; The output end of the fourth AND gate is also connected to the input end of the third AND gate; The input end of the second AND gate is also connected to the second negation module; The output end of the first AND gate, the output end of the first negation module and the output end of the fifth AND gate are connected to the driving circuit module for outputting a control signal to the driving circuit module.

[0009] A further improvement of the safety state control system of the motor control of the present invention is that the driving circuit module includes a driving chip for determining a corresponding safety state according to an input control signal; When the control signal at the output end of the first AND gate is a normal control signal and the output end of the first negation module is 0, the driving chip determines that a normal control state is obtained; When the control signal at the output end of the first AND gate is at a low level, the output end of the first negation module is 1, and the output end of the fifth AND gate is 1, the driver chip determines that an active short circuit fault state is obtained; When the control information of the output end of the first AND gate is at a low level, the output end of the first negation module is 1, and the output end of the fifth AND gate is 0, the driver chip determines that a shutdown fault state is obtained.

[0010] A further improvement of the safe state control system for motor control of the present invention is that the phase voltage monitoring module includes an isolation circuit, a first frequency conversion level circuit and a first level holding circuit; The isolation circuit is used to collect the phase voltage of the motor; The first frequency conversion level circuit is used to output a level voltage Vf_Vo which is proportional to the frequency; The first level holding circuit is used to output a level voltage Va_Vo proportional to the amplitude.

[0011] A further improvement of the safe state control system of the motor control of the present invention is that the phase current monitoring module includes a current sensor, a second frequency conversion level circuit and a second level holding circuit; The current sensor is used to collect the phase current of the motor; The second frequency conversion level circuit is used to output a level voltage If_Vo which is proportional to the frequency; The second level maintaining circuit is used to output a level voltage Ia_Vo proportional to the amplitude.

[0012] A further improvement of the safety state control system of the motor control of the present invention is that when the power supply monitoring chip monitors that a fault occurs in the control chip, the fault enabling state signal outputted by the power supply monitoring chip is at a low level.

[0013] A further improvement of the safety state control system of the motor control of the present invention is that it also includes a low-voltage power supply connected to the power monitoring chip, the motor parameter detection module, the safety state switching judgment module and the drive circuit module.

[0014] A further improvement of the safety state control system for motor control of the present invention is that the power monitoring chip is also used to supply power to the control chip.

[0015] The beneficial effects of the safe state control system of the motor control of the present invention are: The safety state control system of the present invention collects motor voltage and phase current parameters and identifies their frequency as the basis for judging the speed of safety state switching. At the same time, it considers adding the method of judging the operating state based on the voltage and current amplitude, and realizing hysteresis switching. After the control chip fails, it can reliably switch the safety state according to different working conditions, realize more accurate safety state control, make the whole vehicle switching more flexible and output a more reliable safety state. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the system architecture of the safety state control system of the motor control of the present invention.

[0017] Figure 2 The present invention is a schematic diagram of an embodiment of a safety state switching control in a safety state control system for motor control.

[0018] Figure 3 Enter the timing diagram for a possible fault.

[0019] Figure 4 for Figure 3 A local enlarged schematic diagram of point A in the figure.

[0020] Figure 5 Enter the timing diagram for another possible fault.

[0021] Figure 6 for Figure 5 A local enlarged schematic diagram of point B in FIG.

[0022] Figure 7 Enter the timing diagram for another possible fault. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0024] See also Figure 1 The present invention provides a motor-controlled safety state control system, which aims to achieve more accurate safety state control by switching the safety state according to different working conditions through the control system after the control chip fails, making the whole vehicle more flexible and outputting a more reliable safety state. The safety state control system of the present invention collects the motor voltage and phase current parameters, identifies its frequency, and uses it as the basis for judging the speed of the safety state switching. At the same time, it considers adding the operation state judgment based on the voltage and current amplitude, and realizes hysteresis switching. The motor-controlled safety state control system of the present invention is described below in conjunction with the accompanying drawings.

[0025] See also Figure 1 , shows a schematic diagram of the system architecture of the safe state control system of the motor control of the present invention. Figure 1 , the safety state control system of the motor control of the present invention is explained.

[0026] like Figure 1 As shown, the safety state control system of the motor control of the present invention includes a control chip 300, a power monitoring chip 200, a motor parameter detection module 500, a safety state switching judgment module 400, a drive circuit module 600 and a power conversion module 700, wherein the control chip 300 is used to output a pulse width modulation signal, i.e., a PWM signal; the power monitoring chip 200 is connected to the control chip 300, and the power monitoring chip 200 is used to perform safety monitoring on the control chip 300 in real time, and output a fault enabling state signal when a fault occurs in the control chip 300; the motor parameter detection module 500 is connected to the motor, and the motor parameter detection module 500 is used to collect motor parameters and convert them into corresponding voltage signals; the safety state switching judgment module 40 0 is connected to the control chip 300, the power monitoring chip 200 and the motor parameter detection module 500, the safety state switching judgment module 400 is used to receive the pulse width modulation signal output by the control chip 300, the fault enable state signal output by the power monitoring chip 200 and the voltage signal output by the motor parameter detection module 500, and generate a control signal according to the received signal; the drive circuit module 600 is connected to the safety state switching judgment module 400, and the drive circuit module 600 is used to isolate and amplify the control signal; the power conversion module 700 is connected to the drive circuit module 600 and the motor, and the power conversion module 700 is used to make the motor and the safety state control system enter the corresponding safety state according to the input control signal.

[0027] Furthermore, the power conversion module 700 is connected to the motor through the bridge arm circuit. In the normal control state, the PWM signal output by the control chip 300 is transmitted to the drive circuit module 600 after the safety judgment of the safety state switching judgment module 400. The drive circuit module 600 isolates and amplifies the PWM signal, and inputs the isolated and amplified PWM signal to the power conversion module 700. After conversion by the power conversion module 700, the PWM signal is sent to the motor to control the operation of the motor. In an abnormal state, such as the ASC or SPO state, the power conversion module 700 disconnects the motor through the bridge arm circuit and allows the motor and the safety state control system to enter the corresponding ASC or SPO state.

[0028] Further, the safety state control system of the present invention also includes a low-voltage power supply 100 connected to the power monitoring chip 200, the motor parameter detection module 500, the safety state switching judgment module 400 and the drive circuit module 600. The low-voltage power supply 100 is connected to the power monitoring chip 200, the motor parameter detection module 500, the safety state switching judgment module 400 and the drive circuit module 600 through a power line 11, and is used to power the power monitoring chip 200, the motor parameter detection module 500, the safety state switching judgment module 400 and the drive circuit module 600.

[0029] Furthermore, the power monitoring chip 200 is also used to supply power to the control chip 300. The power monitoring chip 200 is also connected to the control chip 300 via the power line 11, and can supply power to the control chip 300. The power monitoring chip 200 is also connected to the control chip 300 via the control signal line 13, so as to realize real-time safety monitoring of the control chip.

[0030] The control chip 300 and the power monitoring chip 200 are connected to the safety status judgment module 400 through a control signal line 13 to realize signal transmission. The safety status judgment module 400 and the driving circuit module 600 are also connected through a control signal line 13 to realize control signal transmission. The driving circuit module 600 and the power conversion module 700 are also connected through a control signal line 13 to realize control signal transmission.

[0031] The motor parameter detection module 500 is connected to the motor and safety state switching judgment module 400 via a signal acquisition line 12 to realize the acquisition of motor parameter signals and the transmission of voltage signals.

[0032] In a specific embodiment of the present invention, Figure 2 As shown, the motor parameter detection module 500 of the present invention includes a phase voltage monitoring module 510 and a phase current monitoring module 520; The phase voltage monitoring module 510 is connected to the motor, and is used to collect the phase voltage of the motor, and output a level voltage Vf_Vo proportional to the frequency and a level voltage Va_Vo proportional to the amplitude; The phase current monitoring module 520 is connected to the motor, and is used to collect the phase current of the motor, and output a level voltage If_Vo proportional to the frequency and a level voltage Ia_Vo proportional to the amplitude.

[0033] Further, the phase voltage monitoring module 510 includes an isolation circuit, a first frequency conversion level circuit and a first level holding circuit; The isolation circuit is used to collect the phase voltage of the motor; The first frequency conversion level circuit is used to output a level voltage Vf_Vo which is proportional to the frequency; The first level holding circuit is used to output a level voltage Va_Vo proportional to the amplitude.

[0034] Specifically, the phase voltage monitoring module 510 includes a phase voltage frequency monitoring module 511 and a phase voltage amplitude monitoring module 512. A common implementation of the phase voltage monitoring module 510 is to collect the phase voltage of the motor through an isolation circuit. A common implementation of the phase voltage frequency monitoring module 511 is to output a level voltage Vf_Vo proportional to the frequency through a first frequency conversion level circuit; a common implementation of the phase voltage amplitude monitoring module 512 is to output a level voltage Va_Vo proportional to the amplitude through a first level holding circuit.

[0035] Further, the phase current monitoring module 520 includes a current sensor, a second frequency conversion level circuit and a second level holding circuit; The current sensor is used to collect the phase current of the motor; The second frequency conversion level circuit is used to output a level voltage If_Vo which is proportional to the frequency; The second level holding circuit is used to output a level voltage Ia_Vo proportional to the amplitude.

[0036] Specifically, the phase current monitoring module 520 includes a phase current frequency monitoring module 521 and a phase current amplitude monitoring module 522. A common implementation of the phase current monitoring module 520 is to collect the phase current of the motor through a current sensor. A common implementation of the phase current frequency monitoring module 521 is to output a level voltage If_Vo proportional to the frequency through a frequency conversion level circuit; a common implementation of the phase current amplitude monitoring module 522 is to output a level voltage Ia_Vo proportional to the amplitude through a level holding circuit.

[0037] The control chip 300 outputs a PWM signal for controlling the motor; the power monitoring chip 200 monitors the operating status of the control chip 300 and outputs a Flt_En signal (ie, a fault enable status signal). When a fault is detected in the control chip 300, the Flt_En signal is a low level signal.

[0038] Further, the safety state switching judgment module 400 includes a first AND gate 401 connected to the control chip 300 and the power monitoring chip 200, a first negation module 411 connected to the power monitoring chip 200, a first comparator 431 whose in-phase input terminal is connected to the output terminal of the level voltage Vf_Vo proportional to the frequency of the phase voltage monitoring module 510, a second comparator 432 whose in-phase input terminal is connected to the output terminal of the level voltage Va_Vo proportional to the amplitude of the phase voltage monitoring module 510, and a third comparator 431 whose in-phase input terminal is connected to the output terminal of the level voltage If_Vo proportional to the frequency of the phase current monitoring module 520. 3. A fourth comparator 434 having a non-inverting input terminal connected to an output terminal of the level voltage Ia_Vo proportional to the amplitude of the phase current monitoring module 520, a second AND gate 402 connected to an output terminal of the first comparator 431, a third AND gate 403 connected to an output terminal of the third comparator 433, a fourth AND gate 404 connected to output terminals of the second comparator 432 and the fourth comparator 434, a second negation module 412 connected to an output terminal of the fourth AND gate 404, an OR gate 421 connected to output terminals of the second AND gate 402 and the third AND gate 403, and a fifth AND gate 405 connected to output terminals of the first negation module 411 and the OR gate 421; The inverting input terminal of the first comparator 431 is a first preset reference voltage Vr1; The non-inverting input terminal of the second comparator 432 is a second preset reference voltage Vr2; The inverting input terminal of the third comparator 433 is a third preset reference voltage Vr3; The inverting input terminal of the fourth comparator 434 is a fourth preset reference voltage Vr4; The output terminal of the fourth AND gate 404 is also connected to the input terminal of the third AND gate 403; The input end of the second AND gate 402 is also connected to the second negation module 412; The output end of the first AND gate 401 , the output end of the first negation module 411 , and the output end of the fifth AND gate 405 are connected to the driving circuit module 600 for outputting a control signal to the driving circuit module 600 .

[0039] Specifically, the input terminals of the first AND gate 401 are the PWM signal and the Flt_En signal, and the first AND gate 401 outputs the final PWM_Ctrl signal.

[0040] When the Flt_En signal is enabled, the bypass PWM input signal is enabled, and FSST_En is output through the first negation module 411 to enable the driving circuit module 600 to enter the safe state.

[0041] The inputs of the fourth AND gate 404 are the outputs of the second comparator 432 and the fourth comparator 434 , and the fourth AND gate 404 outputs the ASC_ST signal.

[0042] Inputs of the third AND gate 403 are the ASC_ST signal and the output of the third comparator 433 .

[0043] The inputs of the OR gate 421 are the output ASC_Tran of the second AND gate 402 and the output SPO_Tran of the third AND gate 403 , and the OR gate 421 outputs a FSST_Tran signal (ASC / SPO switching).

[0044] The inputs of the fifth AND gate 405 are the outputs of the first negation module 411 and the OR gate 421 , and the fifth AND gate 405 outputs the FSST_Ctrl control signal to the driving circuit module 600 .

[0045] The first preset reference voltage Vr1 and the third preset reference voltage Vr3 can be calibrated to correspond to different speed judgment points, so that the switching of ASC and SPO forms a hysteresis loop. The second preset reference voltage Vr2 and the fourth preset reference voltage Vr4 are used to judge the operating state ASC_ST of the motor control system by setting appropriate thresholds; usually, the second preset reference voltage Vr2 sets a threshold value small enough to match the scene with a small phase voltage amplitude under the ASC working condition, and the fourth preset reference voltage Vr4 sets a threshold value large enough to match the scene with a large phase current amplitude under the ASC working condition.

[0046] The setting of the first preset reference voltage value Vr1 is obtained by converting the actual hardware circuit design parameters from the motor electrical frequency corresponding to V2 in Table 1; The third preset reference voltage value Vr3 is set by converting the motor electrical frequency corresponding to V1 in Table 1 through the actual hardware circuit design parameters; The second preset reference voltage value Vr2 can be set to be slightly larger than the phase voltage under the three-phase short circuit of the motor (such as the phase voltage +5V under the actual three-phase short circuit of the motor) according to the actual circuit sampling accuracy and control accuracy, and can be obtained by converting the actual hardware circuit design parameters; The fourth preset reference voltage value Vr4 can be set to be slightly smaller than the phase current amplitude under the three-phase short circuit of the motor (such as the phase voltage under the three-phase short circuit of the motor -10A) according to the actual circuit sampling accuracy and control accuracy, and can be obtained by converting the actual hardware circuit design parameters; Furthermore, the drive circuit module 600 includes a drive chip configured to determine a corresponding safety state based on an input control signal; When the control signal at the output terminal of the first AND gate is a normal control signal and the output terminal of the first inverter module is 0, the drive chip determines a normal control state; When the control signal at the output terminal of the first AND gate is at a low level, the output terminal of the first inverter module is 1, and the output terminal of the fifth AND gate is 1, the drive chip determines an active short circuit fault state; When the control signal at the output terminal of the first AND gate is at a low level, the output terminal of the first inverter module is 1, and the output terminal of the fifth AND gate is 0, the drive chip determines a switch-off fault state.

[0047] Specifically, the inputs of the drive chip are PWM_Ctrl, FSST_En, and FSST_Ctrl control signals, and the output logic of the drive chip is as follows: Normal control state: PWM_Ctrl is a normal PWM control signal, and FSST_En = 0; Fault state ASC: PWM_Ctrl is at a low level, FSST_En = 1; FSST_Ctrl = 1; Fault state SPO: PWM_Ctrl is at a low level, FSST_En = 1; FSST_Ctrl = 0.

[0048] The drive circuit module 600 of the present invention includes a drive chip that meets the requirements of functional safety and can enter and maintain a safety state by setting corresponding safety pins.

[0049] To enable the safety state to be switched according to the rotational speed identified by the motor parameters at this time, so as to meet the operating states of medium and high speed ASC and low speed SPO, the implementation logic of the safety state is shown in Table 1, where the rotational speed switching point V1 corresponds to the setting of the threshold of the first preset reference voltage Vr1, and the rotational speed switching point V2 corresponds to the setting of the threshold of the third preset reference voltage Vr3. And V1 < V2, so as to have a sufficient hysteresis interval, for example, the difference between the two is 100 rpm.

[0050] Table 1: Safety state logic table.

[0051] The value of V1 is strongly related to the parameters of the controlled permanent magnet synchronous motor and the magnitude of the DC bus voltage. In typical applications, V1 can be selected as the rotational speed point where the back electromotive force of the permanent magnet synchronous motor is close to the magnitude of the DC bus voltage; The value of V2 is set to reserve a sufficient hysteresis interval for the switching of the safety state. For example, V2 can be set to V1 + 100 rpm.

[0052] Figures 3 to 7The timing of the safety status judgment module based on different fault occurrence timings is shown.

[0053] like Figure 3 and Figure 4 As shown, it is the safety fault enabled state during normal operation at medium and high speed. When the speed is higher than V1, after the fault is enabled, FSST_Ctrl is set to 1, and the safety state enters and maintains ASC; until FSST_Ctrl is set to 0 at low speed, it enters and maintains the SPO state, which is consistent with the design logic.

[0054] like Figure 5 and Figure 6 As shown in the figure, the safety fault enabled state is entered during normal operation at medium and high speeds, and the speed rises again due to actual working conditions such as downhill. When the speed is higher than V1, after the fault is enabled, FSST_Ctrl is set to 1, and the safety state enters ASC and maintains; until the FSST_Ctrl is set to 0 at low speed, it enters and maintains the SPO state. When the speed is higher than V2 again, FSST_Ctrl is set to 1, and the safety state enters ASC and maintains, until the speed is less than V1 again, FSST_Ctrl is set to 0 again, and the safety state enters SPO, which is consistent with the design logic.

[0055] like Figure 7 As shown in the figure, the safety fault enable state is entered at low speed and high current. It can be seen that ASC_ST is set to 1 at this time, and by judging that FSST_Tran is 0, when Flt_En is set, FSST_Ctrl output is 0, so that the controller is maintained in the SPO state at this time, which is consistent with the design logic.

[0056] After the control chip fails, the safety state control system of the present invention can still judge the switching of the safety state according to the motor parameters and realize hysteresis switching.

[0057] When the control chip fails, not only can the safe state be entered based on fault judgment, but the safe state can also be switched in real time according to the working conditions in the fault state.

[0058] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A safe state control system for motor control, characterized in that: include: A control chip for outputting a pulse width modulation signal; A power monitoring chip connected to the control chip, used to monitor the safety of the control chip in real time and output a fault enabling state signal when a fault occurs in the control chip; A motor parameter detection module connected to the motor, used to collect motor parameters and convert them into corresponding voltage signals; A safety state switching judgment module is connected to the control chip, the power monitoring chip and the motor parameter detection module, and is used to receive the pulse width modulation signal output by the control chip, the fault enable state signal output by the power monitoring chip and the voltage signal output by the motor parameter detection module, and generate a control signal according to the received signal; A driving circuit module connected to the safety state switching judgment module, used to isolate and amplify the control signal; The power conversion module connected to the driving circuit module and the motor is used to make the motor and the safety state control system enter a corresponding safety state according to an input control signal.

2. The safe state control system for motor control according to claim 1, characterized in that: The motor parameter detection module includes a phase voltage monitoring module and a phase current monitoring module; The phase voltage monitoring module is connected to the motor, and is used to collect the phase voltage of the motor, and output a level voltage Vf_Vo proportional to the frequency and a level voltage Va_Vo proportional to the amplitude; The phase current monitoring module is connected to the motor, and is used to collect the phase current of the motor, and output a level voltage If_Vo proportional to the frequency and a level voltage Ia_Vo proportional to the amplitude.

3. The safe state control system for motor control according to claim 2, characterized in that: The safety state switching judgment module includes a first AND gate connected to the control chip and the power monitoring chip, a first negation module connected to the power monitoring chip, a first comparator whose in-phase input terminal is connected to the output terminal of the level voltage Vf_Vo proportional to the frequency of the phase voltage monitoring module, a second comparator whose in-phase input terminal is connected to the output terminal of the level voltage Va_Vo proportional to the amplitude of the phase voltage monitoring module, a third comparator whose in-phase input terminal is connected to the output terminal of the level voltage If_Vo proportional to the frequency of the phase current monitoring module, a fourth comparator whose in-phase input terminal is connected to the output terminal of the level voltage Ia_Vo proportional to the amplitude of the phase current monitoring module, a second AND gate connected to the output terminal of the first comparator, a third AND gate connected to the output terminal of the third comparator, a fourth AND gate connected to the output terminals of the second comparator and the fourth comparator, a second negation module connected to the output terminal of the fourth AND gate, an OR gate connected to the output terminals of the second AND gate and the third AND gate, and a fifth AND gate connected to the output terminals of the first negation module and the OR gate; The inverting input terminal of the first comparator is a first preset reference voltage Vr1; The non-inverting input terminal of the second comparator is a second preset reference voltage Vr2; The inverting input terminal of the third comparator is a third preset reference voltage Vr3; The inverting input terminal of the fourth comparator is a fourth preset reference voltage Vr4; The output end of the fourth AND gate is also connected to the input end of the third AND gate; The input end of the second AND gate is also connected to the second negation module; The output end of the first AND gate, the output end of the first negation module and the output end of the fifth AND gate are connected to the driving circuit module for outputting a control signal to the driving circuit module.

4. The safe state control system for motor control according to claim 3, characterized in that: The driving circuit module includes a driving chip for determining a corresponding safety state according to an input control signal; When the control signal at the output end of the first AND gate is a normal control signal and the output end of the first negation module is 0, the driving chip determines that a normal control state is obtained; When the control signal at the output end of the first AND gate is at a low level, the output end of the first negation module is 1, and the output end of the fifth AND gate is 1, the driver chip determines that an active short circuit fault state is obtained; When the control information of the output end of the first AND gate is at a low level, the output end of the first negation module is 1, and the output end of the fifth AND gate is 0, the driver chip determines that a shutdown fault state is obtained.

5. The safe state control system for motor control according to claim 2, characterized in that: The phase voltage monitoring module includes an isolation circuit, a first frequency conversion level circuit and a first level holding circuit; The isolation circuit is used to collect the phase voltage of the motor; The first frequency conversion level circuit is used to output a level voltage Vf_Vo which is proportional to the frequency; The first level holding circuit is used to output a level voltage Va_Vo proportional to the amplitude.

6. The safe state control system for motor control according to claim 2, characterized in that: The phase current monitoring module includes a current sensor, a second frequency conversion level circuit and a second level holding circuit; The current sensor is used to collect the phase current of the motor; The second frequency conversion level circuit is used to output a level voltage If_Vo which is proportional to the frequency; The second level maintaining circuit is used to output a level voltage Ia_Vo proportional to the amplitude.

7. The safe state control system for motor control according to claim 1, characterized in that: When the power monitoring chip detects that the control chip has a fault, the fault enabling state signal output by the power monitoring chip is a low level.

8. The safe state control system for motor control according to claim 1, characterized in that: It also includes a low-voltage power supply connected to the power monitoring chip, the motor parameter detection module, the safety state switching judgment module and the drive circuit module.

9. The safe state control system for motor control according to claim 1, characterized in that: The power monitoring chip is also used to supply power to the control chip.

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