Motor overcurrent protection circuit, controller and vehicle

Abstract

The utility model provides a motor overcurrent protection circuit, a controller and a vehicle, and belongs to the technical field of electronics. The motor overcurrent protection circuit comprises an on-off control circuit and an overcurrent control circuit. The on-off control circuit is connected with a motor control circuit, a motor and the over-current control circuit, and is used for connecting or disconnecting the motor control circuit and the motor under the control of the over-current control circuit; the over-current control circuit is connected with a motor and used for collecting detection voltage corresponding to output current of the motor, and under the condition that the detection voltage exceeds a target voltage range, the on-off control circuit is controlled to disconnect the motor control circuit and the motor. The motor control circuit can effectively prevent back electromotive force current generated when the motor stops working from recharging to the motor control circuit, effectively realizes overcurrent protection of the motor control circuit, and prevents the problem of device damage caused by overcurrent risk of the motor control circuit.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronics, and in particular to a motor overcurrent protection circuit, a controller and a vehicle. BACKGROUND

[0002] With the development of new energy electric vehicles, range anxiety has become the biggest bottleneck restricting the prosperity of the electric vehicle market. The causes of range anxiety mainly focus on "short range" and "slow charging". Therefore, a high-voltage system for electric vehicles emerges as the times require, which is equipped with a power battery, a motor and a motor control circuit. The motor control circuit is used to control the motor to output a power supply signal with high voltage, large current and large power characteristics to the power battery, so as to make the power battery have a higher charging speed and effectively alleviate the range anxiety of new energy electric vehicles.

[0003] The core device of the motor control circuit of the new energy electric vehicle is an Insulate-Gate Bipolar Transistor (IGBT) power device. However, in the high-voltage system, the power device is prone to overcurrent damage. Therefore, the overcurrent protection work in the high-voltage system is particularly important. The current overcurrent protection circuit usually collects the output current of the motor, converts the output current into a voltage, and then judges the size of the voltage and the threshold voltage, so that when the voltage is greater than the threshold voltage, indicating that the output current is overcurrent, the power devices in the upper and lower bridge arms of the motor control circuit are disconnected, so that the motor control circuit controls the motor to stop working, and the overcurrent protection of the motor control circuit is realized.

[0004] However, in order to ensure that the motor has high output power in the high-voltage system, the speed of the motor is usually fast. This results in a large back electromotive force of the motor at the moment of stopping running, generating a back electromotive force current. The back electromotive force current will flow back to other devices in the motor control circuit through the body diode of the power device, so that the motor control circuit is prone to device damage problems. SUMMARY

[0005] The motor overcurrent protection circuit, the controller and the vehicle provided by the embodiments of the present application can effectively prevent the back electromotive force current generated by the motor when it stops working from flowing back to the motor control circuit, effectively realize the overcurrent protection of the motor control circuit, and prevent the motor control circuit from being damaged due to overcurrent risk.

[0006] In a first aspect, the embodiments of the present application provide an overvoltage protection circuit, the motor overcurrent protection circuit comprising: a on-off control circuit and an overcurrent control circuit.

[0007] The on-off control circuit is connected with the motor control circuit, the motor and the overcurrent control circuit, and is configured to connect or disconnect the motor control circuit and the motor under the control of the overcurrent control circuit.

[0008] The overcurrent control circuit is connected with the motor, and is configured to collect a detection voltage corresponding to an output current of the motor, and control the on-off control circuit to disconnect the motor control circuit and the motor when the detection voltage exceeds a target voltage range.

[0009] Optionally, the on-off control circuit comprises at least one on-off control unit, and each on-off control unit is connected with the motor control circuit, the overcurrent control circuit and a phase current output end of the motor, and is configured to connect or disconnect the phase current output end and the motor control circuit under the control of the overcurrent control circuit.

[0010] Optionally, the on-off control circuit comprises three on-off control units, and each on-off control unit is connected with the motor control circuit, the overcurrent control circuit and a different phase current output end of the motor.

[0011] Optionally, the on-off control unit comprises an isolation switch device, and the isolation switch device is connected with the motor control circuit, the overcurrent control circuit and the phase current output end, and is configured to connect or disconnect the phase current output end and the motor control circuit under the control of the overcurrent control circuit.

[0012] Optionally, the isolation switch device comprises a relay, and the relay is connected with the motor control circuit, the overcurrent control circuit and the phase current output end, and is configured to connect or disconnect the phase current output end and the motor control circuit under the control of the overcurrent control circuit.

[0013] Optionally, the on-off control unit further comprises a current blocking component, and the current blocking component is connected with the isolation switch device in parallel, and is configured to prevent an output signal of the phase current output end from flowing to the motor control circuit when the isolation switch device disconnects the phase current output end and the motor control circuit.

[0014] Optionally, the current blocking component comprises a first resistor, and the first resistor is connected with the isolation switch device in parallel.

[0015] Optionally, the current blocking component comprises a first diode, a cathode of the first diode is connected with the phase current output end, and an anode of the first diode is connected with the motor control circuit.

[0016] Optionally, the current blocking component comprises a first resistor and a first diode.

[0017] a cathode of the first diode is connected with the phase current output terminal, and an anode of the first diode is connected with the motor control circuit through the first resistor.

[0018] Alternatively, a cathode of the first diode is connected with the phase current output terminal, and an anode of the first diode is connected with the motor control circuit through the first resistor.

[0019] Optionally, the overcurrent control circuit comprises a control unit and three detection units.

[0020] Each detection unit is connected with the control unit and a different phase current output terminal of the motor, and is configured to collect a detection voltage corresponding to an output current of the phase current output terminal, and output an overcurrent fault signal to the control unit when the detection voltage exceeds a target voltage range.

[0021] The control unit is configured to receive the overcurrent fault signal, and control the on-off control circuit to at least disconnect a connection between the motor control circuit and a target output terminal of the motor, and the detection voltage corresponding to an output current of the target output terminal exceeds the target voltage range.

[0022] Optionally, the detection unit comprises a current detection module and a comparison module.

[0023] The current detection module is connected with the phase current output terminal and the comparison module, and is configured to collect an output current of the phase current output terminal, convert the output current into a detection voltage, and output the detection voltage to the comparison module.

[0024] The comparison module is connected with the control unit, and is configured to output an overcurrent fault signal to the control unit when the detection voltage exceeds a target voltage range.

[0025] Optionally, the current detection module comprises a current sensor.

[0026] The current sensor is connected with the phase current output terminal and the comparison module, and is configured to collect an output current of the phase current output terminal, convert the output current into a detection voltage, and output the detection voltage to the comparison module.

[0027] Optionally, the comparison module comprises a comparator and a processing submodule.

[0028] The processing submodule is connected with the comparator, and is configured to provide an upper threshold voltage and a lower threshold voltage of the target voltage range to the comparator.

[0029] The comparator is connected with the current detection module, and is configured to receive the detection voltage, and output an overcurrent fault signal to the processing submodule when the detection voltage is less than the lower threshold voltage or the detection voltage is greater than the upper threshold voltage.

[0030] The processing submodule is connected with the control unit, and is configured to receive the overcurrent fault signal output by the comparator and output the overcurrent fault signal to the control unit.

[0031] Optionally, the detection unit further comprises a voltage conversion module.

[0032] The voltage conversion module is connected with the current detection module and the comparison module, and is configured to receive the detection voltage output by the current detection module, and output the detection voltage after impedance conversion to the comparison module.

[0033] Optionally, the voltage conversion module comprises a voltage follower.

[0034] The voltage follower is connected with the current detection module and the comparison module, and is configured to output the detection voltage after impedance conversion to the comparison module.

[0035] Optionally, the detection unit further comprises a clamping module.

[0036] The clamping module is connected with the current detection module and the motor controller, and is configured to receive the detection voltage output by the current detection module, clamp the detection voltage to an input voltage range of the motor controller to obtain a controller detection voltage, and output the controller detection voltage to the motor controller.

[0037] The motor controller is configured to control the motor control circuit to connect or disconnect a motor power supply and the motor according to the controller detection voltage.

[0038] In a second aspect, a controller is provided, and the controller comprises the motor overcurrent protection circuit according to any one of the first aspect.

[0039] In a third aspect, a vehicle is provided, and the vehicle comprises the controller according to the second aspect.

[0040] The application has the following advantages:

[0041] The motor control circuit and the motor are connected in isolation through the on-off control circuit. The overcurrent control circuit is used to collect the detection voltage corresponding to the output current of the motor. When the detection voltage exceeds the target voltage range, it indicates that the motor has overcurrent output, and the motor control circuit has the risk of overcurrent damage. In this case, the on-off control circuit can control the disconnection of the motor control circuit and the motor to stop the motor. Since the on-off control circuit can isolate the motor control circuit and the motor after disconnecting the motor control circuit and the motor, there is no electrical connection between the motor control circuit and the motor. Therefore, the backflow of the counter electromotive force current generated by the stopped motor to the motor control circuit can be effectively prevented, and the overcurrent protection of the motor control circuit can be effectively realized to prevent the device damage problem of the motor control circuit caused by the overcurrent risk. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiment description will be briefly introduced as follows.

[0043] Figure 1 A structural schematic diagram of a motor control circuit provided by an embodiment of the present application is shown in the figure.

[0044] Figure 2 A structural schematic diagram of a motor overcurrent protection circuit provided by an embodiment of the present application is shown in the figure.

[0045] Figure 3 A structural schematic diagram of an on-off control circuit provided by an embodiment of the present application is shown in the figure.

[0046] Figure 4 A structural schematic diagram of another on-off control circuit provided by an embodiment of the present application is shown in the figure.

[0047] Figure 5 A structural schematic diagram of an overcurrent control circuit provided by an embodiment of the present application is shown in the figure.

[0048] Figure 6 A structural schematic diagram of another overcurrent control circuit provided by an embodiment of the present application is shown in the figure.

[0049] Figure 7 A structural schematic diagram of another overcurrent control circuit provided by an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0050] Exemplary embodiments of the present application will be described in more detail by referring to the accompanying drawings. Although exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0051] In order to better understand the technical solutions of the present application, the working circuit of the motor is introduced as follows. As shown in Figure 1 the working circuit of the motor includes: a motor control circuit 11, a motor controller (not shown in the figure), a motor power supply Vdc and a bus capacitor Cdc. The motor control circuit 11 is connected with the motor 2 and the motor controller respectively. And the motor control circuit 11 is also connected with the motor power supply Vdc through the bus capacitor Cdc. Figure 1

[0052] Among them, the motor control circuit 11 usually includes: a first complementary switching circuit, a second complementary switching circuit and a third complementary switching circuit. The first complementary switching circuit is connected with the motor controller, the motor power supply Vdc and the first phase current output end of the motor 2. The second complementary switching circuit is connected with the motor controller, the motor power supply Vdc and the second phase current output end of the motor 2. The third complementary switching circuit is connected with the motor controller, the motor power supply Vdc and the third phase current output end of the motor 2. The motor 2 outputs three-phase current through the first phase current output end, the second phase current output end and the third phase current output end.

[0053] Specifically, the first complementary switching circuit includes a first IGBT Q1 and a second IGBT Q2. The first end (i.e. the control end) of the first IGBT Q1 is connected with the motor controller, the second end of the first IGBT Q1 is connected with the motor power supply Vdc, and the third end of the first IGBT Q1 is connected with the first phase current output end of the motor 2 and the second end of the second IGBT Q2. The first end (i.e. the control end) of the second IGBT Q2 is connected with the motor controller, and the third end of the second IGBT Q2 is connected with the motor power supply Vdc.

[0054] The second complementary switching circuit includes a third IGBT Q3 and a fourth IGBT Q4. The first end (i.e. the control end) of the third IGBT Q3 is connected with the motor controller, the second end of the third IGBT Q3 is connected with the motor power supply Vdc, and the third end of the third IGBT Q3 is connected with the second phase current output end of the motor 2 and the second end of the fourth IGBT Q4. The first end (i.e. the control end) of the fourth IGBT Q4 is connected with the motor controller, and the third end of the fourth IGBT Q4 is connected with the motor power supply Vdc.

[0055] ​The third complementary switch circuit includes a fifth IGBT Q5 and a sixth IGBT Q6. The first end (i.e., the control end) of the fifth IGBT Q5 is connected with the motor controller, the second end of the fifth IGBT Q5 is connected with the motor power supply Vdc, and the third end of the fifth IGBT Q5 is connected with the third-phase current output end of the motor 2 and the second end of the sixth IGBT Q6. The first end (i.e., the control end) of the sixth IGBT Q6 is connected with the motor controller, and the third end of the sixth IGBT Q6 is connected with the motor power supply Vdc.

[0056] The motor controller controls the conduction or turn-off of the first IGBT Q1, the second IGBT Q2, the third IGBT Q3, the fourth IGBT Q4, the fifth IGBT Q5, and the sixth IGBT Q6, so as to control the communication or disconnection of the motor power supply Vdc and the first-phase current output end, the second-phase current output end, and the third-phase current output end of the motor 2, thereby realizing the control of the working state of the motor 2.

[0057] It should be noted that the first-phase current output end is taken as the output end A of the A-phase current of the motor, the second-phase current output end is taken as the output end B of the B-phase current of the motor, and the third-phase current output end is taken as the output end C of the C-phase current of the motor in the introduction of the present application (for example, Figure 1 , Figure 3 , etc.).

[0058] Please refer to Figure 2 , which shows a circuit schematic diagram of a motor overcurrent protection circuit provided by an embodiment of the present application. As shown in Figure 2 , the motor overcurrent protection circuit 3 includes a on-off control circuit 31 and an overcurrent control circuit 32.

[0059] The on-off control circuit 31 is connected with the motor control circuit 11, the motor 2, and the overcurrent control circuit 32. The on-off control circuit 31 is configured to be controlled by the overcurrent control circuit 32 to connect or disconnect the motor control circuit 11 and the motor 2.

[0060] The overcurrent control circuit 32 is connected with the motor 2. The overcurrent control circuit 32 is configured to collect a detection voltage V1 corresponding to the output current of the motor 2, and control the on-off control circuit 32 to disconnect the connection between the motor control circuit 11 and the motor 2 to isolate the motor control circuit 11 and the motor 2 in the case that the detection voltage V1 exceeds a target voltage range.

[0061] In the embodiments of the present application, the overcurrent control circuit 32 is configured to collect the detection voltage V1 corresponding to the output current of the motor 2, and compare the detection voltage V1 with the upper threshold voltage of the target voltage range and the lower threshold voltage of the target voltage range. When the detection voltage V1 is greater than or equal to the lower threshold voltage and less than or equal to the upper threshold voltage, the overcurrent control circuit 32 determines that the detection voltage V1 does not exceed the target voltage range, and the output current of the motor 2 belongs to the normal current range, and then controls the on-off control circuit 32 to connect the motor control circuit 11 and the motor 2, so as to ensure the normal operation of the motor 2.

[0062] When the detection voltage V1 is less than the lower threshold voltage or greater than the upper threshold voltage, the overcurrent control circuit 32 determines that the detection voltage V1 exceeds the target voltage range, and the output current of the motor 2 exceeds the normal current range, and then controls the on-off control circuit 32 to disconnect the connection between the motor control circuit 11 and the motor 2, so as to isolate the motor control circuit 11 and the motor 2, control the motor 2 to stop working, and realize the overcurrent protection of the motor control circuit 11.

[0063] In the embodiments of the present application, the motor control circuit and the motor are connected in an isolated manner through the on-off control circuit. The overcurrent control circuit is configured to collect the detection voltage corresponding to the output current of the motor, and when the detection voltage exceeds the target voltage range, indicating that the motor has overcurrent output and the motor control circuit has the risk of overcurrent damage, the on-off control circuit can be controlled to disconnect the motor control circuit and the motor, so that the motor stops working. Since the on-off control circuit can isolate the motor control circuit and the motor after disconnecting the motor control circuit and the motor, there is no electrical connection between the motor control circuit and the motor. Therefore, the backflow of the counter electromotive force current generated by the motor stopping working to the motor control circuit can be effectively prevented, and the overcurrent protection of the motor control circuit can be effectively realized, and the device damage problem of the motor control circuit caused by the overcurrent risk can be prevented.

[0064] In some embodiments of the present application, the on-off control circuit 31 can be connected with at least one phase current output end of the motor 2 respectively, and is configured to control the connection or disconnection of the phase current output end of the motor 2 and the motor control circuit 11 under the control of the overcurrent control circuit 32, so as to control the working state of the motor 2.

[0065] Optionally, the on-off control circuit 31 includes at least one on-off control unit 311. Each on-off control unit 311 is connected with the motor control circuit 11, the overcurrent control circuit 32, and the phase current output end of the motor 2. Each on-off control unit 311 is configured to connect or disconnect the phase current output end and the motor control circuit 11 under the control of the overcurrent control circuit 32.

[0066] In an alternative case, the on-off control circuit 31 comprises one on-off control unit 311. The on-off control unit 311 can be connected with one phase current output terminal of the motor 2. The on-off control unit 311 is used to connect or disconnect the phase current output terminal connected with the on-off control unit 311 and the motor control circuit 11 under the control of the overcurrent control circuit 32.

[0067] Alternatively, the on-off control unit 311 can be connected with three phase current output terminals of the motor 2 respectively. The on-off control unit 311 is used to connect or disconnect the three phase current output terminals and the motor control circuit 11 simultaneously under the control of the overcurrent control circuit 32, to realize the synchronous control of the working state of the three-phase current of the motor 2, and has the characteristic of simple control.

[0068] In another alternative case, the on-off control circuit 31 comprises two on-off control units 311. Each on-off control unit 311 can be connected with a different phase current output terminal of the motor 2 respectively. Each on-off control unit 311 is used to connect or disconnect the phase current output terminal connected with the on-off control unit 311 and the motor control circuit 11 under the control of the overcurrent control circuit 32, to realize the separate control of the working state of two-phase current of the three-phase current of the motor 2.

[0069] In another alternative case, the on-off control circuit 31 can also be connected with three phase current output terminals of the motor 2 respectively, to control the connection or disconnection of the three phase current output terminals of the motor 2 and the motor control circuit 11 respectively under the control of the overcurrent control circuit 32, to realize the separate control of the working state of the three-phase current of the motor 2.

[0070] Based on this alternative, as shown in Figure 3 The on-off control circuit 31 comprises three on-off control units 311. Each on-off control unit 311 is connected with the motor control circuit 11, the overcurrent control circuit 32, and a different phase current output terminal of the motor 2. Each on-off control unit 311 is used to connect or disconnect one phase current output terminal and the motor control circuit 11 under the control of the overcurrent control circuit 32.

[0071] In particular, please continue to refer to Figure 3The three on-off control units 311 include a first on-off control unit 311, a second on-off control unit 311 and a third on-off control unit 311. The first on-off control unit 311 is connected with the first phase current output end A of the motor 2. The first on-off control unit 311 is used to connect or disconnect the first phase current output end A and the motor control circuit 11 under the control of the overcurrent control circuit 32. The second on-off control unit 311 is connected with the second phase current output end B of the motor 2. The second on-off control unit 311 is used to connect or disconnect the second phase current output end B and the motor control circuit 11 under the control of the overcurrent control circuit 32. The third on-off control unit 311 is connected with the third phase current output end C of the motor 2. The third on-off control unit 311 is used to connect or disconnect the third phase current output end C and the motor control circuit 11 under the control of the overcurrent control circuit 32.

[0072] In some embodiments, as shown in FIG. 3, the on-off control unit 311 includes a disconnecting switch device 3111. The disconnecting switch device 3111 is connected with the motor control circuit 11, the overcurrent control circuit 32 and the phase current output end of the motor 2. The disconnecting switch device 3111 is used to connect or disconnect the phase current output end and the motor control circuit 11 under the control of the overcurrent control circuit 32. Figure 3

[0073] Optionally, as shown in FIG. 3, the disconnecting switch device 3111 includes a relay S. The relay S is connected with the motor control circuit 11, the overcurrent control circuit 32 and the phase current output end of the motor 2. The relay S is used to connect or disconnect the phase current output end and the motor control circuit 11 under the control of the overcurrent control circuit 32. Figure 4

[0074] For example, the stationary contact of the relay S can be connected with the motor control circuit 11, the movable contact can be connected with the phase current output end of the motor 2, and the coil is connected with the overcurrent control circuit 32. The overcurrent control circuit 32 can control the coil of the relay S to be powered on, so that the electromagnet drives the movable contact to move, and then the movable contact is connected with the stationary contact, and the phase current output end and the motor control circuit 11 are connected. The overcurrent control circuit 32 can also control the coil of the relay S to be powered off, so that the electromagnet returns to the original position, the movable contact is disconnected with the stationary contact, and the phase current output end and the motor control circuit 11 are disconnected.

[0075] It should be noted that the disconnecting switch device 3111 can also be a photoelectric coupler or other device that can isolate the connection between the phase current output end and the motor control circuit 11, and the embodiments of the present application do not limit this.

[0076] Optionally, as shown in FIG. 3, the disconnecting switch device 3111 includes a relay S. The relay S is connected with the motor control circuit 11, the overcurrent control circuit 32 and the phase current output end of the motor 2. The relay S is used to connect or disconnect the phase current output end and the motor control circuit 11 under the control of the overcurrent control circuit 32. Figure 3 ​​As shown, the on-off control unit 311 can further include a current blocking component 3112. The current blocking component 3112 is connected in parallel with the isolating switch device 3111. The current blocking component 3112 is configured to block the output signal of the phase current output end from flowing to the motor control circuit in the case that the isolating switch device 3111 disconnects the phase current output end and the motor control circuit 11. Specifically, the current blocking component 3112 can be configured to block the back electromotive force current generated by the motor 2 due to the stop of the motor from flowing to the motor control circuit 11 in the case that the isolating switch device 3111 disconnects the phase current output end and the motor control circuit 11, effectively protecting the motor control circuit 11 and preventing the relay from sintering.

[0077] In some embodiments, the current blocking component 3112 includes a first resistor R1 connected in parallel with the isolating switch device 3111. In this way, the first resistor R1 can share the back electromotive force of the motor 2 to block the back electromotive force current from flowing to the motor control circuit, and convert the energy of the back electromotive force current into heat energy dissipated in the environment, thereby further consuming the output signal of the motor 2 to more effectively block the back electromotive force current from flowing to the motor control circuit and prevent the relay from sintering.

[0078] In other embodiments, the current blocking component 3112 includes a first diode D1. The cathode of the first diode D1 is connected to the phase current output end, and the anode of the first diode D1 is connected to the motor control circuit 11. In this way, the first diode D1 can effectively cut off the back electromotive force current flowing to the motor control circuit 11, effectively protecting the motor control circuit 11 and preventing the relay from sintering.

[0079] In still other embodiments, as shown in Figure 4 the current blocking component 3112 includes a first resistor R1 and a first diode D1. The cathode of the first diode D1 is connected to the phase current output end through the first resistor R1, and the anode of the first diode D1 is connected to the motor control circuit 11. Alternatively, the cathode of the first diode D1 is connected to the phase current output end, and the anode of the first diode D1 is connected to the motor control circuit 11 through the first resistor R1. In this way, by connecting the first resistor R1 and the first diode D1 in parallel on the isolating switch device 3111, the back electromotive force current generated by the motor 2 can be effectively shunted and blocked from flowing back to the motor control circuit 11, effectively protecting the motor control circuit 11 and preventing the relay from sintering.

[0080] In some embodiments of the present application, as shown in Figure 5 the overcurrent control circuit 32 can include a control unit 321 and three detection units 322.

[0081] Each detection unit 322 is connected with the control unit 321 and a different phase current output terminal of the motor 2. Each detection unit 322 is configured to collect a detection voltage V1 corresponding to an output current of the phase current output terminal, and output an overcurrent fault signal to the control unit 321 when the detection voltage V1 exceeds a target voltage range.

[0082] The control unit 321 is configured to receive the overcurrent fault signal, and control the on-off control circuit 31 to at least disconnect the connection between the motor control circuit 11 and the target output terminal of the motor 2. The detection voltage corresponding to the output current of the target output terminal exceeds the target voltage range. Optionally, the control unit 321 can be a programmable control chip, a Field-Programmable Gate Array (FPGA), a Complex Programmable Logic Device (CPLD), a Digital Signal Process (DSP) chip, or the like.

[0083] In some embodiments, the three detection units 322 include a first detection unit 322, a second detection unit 322, and a third detection unit 322. The first detection unit 322 is connected with the control unit 321 and a first phase current output terminal of the motor 2. The first detection unit 322 is configured to collect a detection voltage V1 corresponding to an output current of the first phase current output terminal, and output an overcurrent fault signal to the control unit 321 when the detection voltage V1 exceeds a target voltage range.

[0084] The second detection unit 322 is connected with the control unit 321 and a second phase current output terminal of the motor 2. The second detection unit 322 is configured to collect a detection voltage V1 corresponding to an output current of the second phase current output terminal, and output an overcurrent fault signal to the control unit 321 when the detection voltage V1 exceeds a target voltage range.

[0085] The third detection unit 322 is connected with the control unit 321 and a third phase current output terminal of the motor 2. The third detection unit 322 is configured to collect a detection voltage V1 corresponding to an output current of the third phase current output terminal, and output an overcurrent fault signal to the control unit 321 when the detection voltage V1 exceeds a target voltage range.

[0086] The control unit 321 is configured to control the on-off control circuit 31 to disconnect the connection between the motor control circuit 11 and the target output terminal of the motor 2 when the overcurrent fault signal is received. Alternatively, the control unit 321 can also be configured to control the on-off control circuit 31 to disconnect the connection between the motor control circuit 11 and each phase current output terminal of the motor 2 when the overcurrent fault signal is received.

[0087] For example, the control unit 321 can be configured to control the target relay S to disconnect the connection between the motor control circuit 11 and the phase current output terminal in the case where the overcurrent fault signal is received. In an alternative case, the target relay S is a relay S connected to the target output terminal. The output current of the target output terminal corresponds to a detection voltage exceeding the target voltage range. In another alternative case, the target relay S is all the relays S in the three on-off control units 311.

[0088] For example, the control unit 321 can be configured to output a disconnect control signal to the target relay S in the case where the overcurrent fault signal is received. The target relay S is configured to disconnect the connection between the motor control circuit 11 and the phase current output terminal in the case where the disconnect control signal is received. Of course, the control unit 321 can also be configured to output a connect control signal to the target relay S in the case where the overcurrent fault signal is not received. The target relay S is configured to connect the motor control circuit 11 and the phase current output terminal in the case where the connect control signal is received.

[0089] Optionally, as shown in Figure 5 Each detection unit 322 can include a current detection module 3221 and a comparison module 3222.

[0090] The current detection module 3221 is connected to the phase current output terminal and the comparison module 3222. The current detection module 3221 is configured to collect the output current of the phase current output terminal and convert the output current into a detection voltage V1, and output the detection voltage V1 to the comparison module 3222.

[0091] The comparison module 3222 is connected to the control unit 321. The comparison module 3222 is configured to output an overcurrent fault signal to the control unit 321 in the case where the detection voltage V1 exceeds the target voltage range.

[0092] In some embodiments of the present application, the comparison module 3222 is configured to receive the detection voltage V1 transmitted by the current detection module 3221, and compare the detection voltage V1 with the upper threshold voltage of the target voltage range and the lower threshold voltage of the target voltage range.

[0093] The comparison module 3222 is configured to determine that the detection voltage V1 does not exceed the target voltage range and the output current of the motor 2 belongs to the normal current range in the case where the detection voltage V1 is greater than or equal to the lower threshold voltage and less than or equal to the upper threshold voltage, and output a normal working signal to the control unit 321. The control unit 321 is configured to control the on-off control circuit 31 to connect the motor control circuit 11 and the motor 2 in the case where the normal working signal is received, so as to guarantee the normal working of the motor 2.

[0094] The comparison module 3222 is further configured to determine that the detection voltage V1 is out of the target voltage range and the output current of the motor 2 is out of the normal current range, and output an overcurrent fault signal to the control unit 321, in the case that the detection voltage V1 is less than the lower threshold voltage, or the detection voltage V1 is greater than the upper threshold voltage. The control unit 321 is configured to control the on-off control circuit 32 to disconnect the connection between the motor control circuit 11 and the motor 2, to isolate the motor control circuit 11 and the motor 2, in the case that the overcurrent fault signal is received.

[0095] Further optionally, as shown in Figure 6 The comparison module 3222 can include a comparator 32221 and a processing submodule 32222.

[0096] The processing submodule 32222 is connected with the comparator 32221. The processing submodule 32222 is configured to output the upper threshold voltage and the lower threshold voltage of the target voltage range to the comparator 32221.

[0097] The comparator 32221 is connected with the current detection module 3221. The comparator 32221 is configured to receive the detection voltage V1, and output an overcurrent fault signal to the processing submodule 32222, in the case that the detection voltage V1 is less than the lower threshold voltage, or the detection voltage V1 is greater than the upper threshold voltage.

[0098] The processing submodule 32222 is connected with the control unit 321. The processing submodule 32222 is configured to receive the overcurrent fault signal output by the comparator 32221, and output the overcurrent fault signal to the control unit 321.

[0099] In some embodiments, the comparator 32221 is further configured to output a normal working signal to the processing submodule 32222, in the case that the detection voltage V1 is greater than or equal to the lower threshold voltage, and the detection voltage V1 is less than or equal to the upper threshold voltage. Correspondingly, the processing submodule 32222 is further configured to receive the normal working signal output by the comparator 32221, and output the normal working signal to the control unit 321.

[0100] In some embodiments, the processing submodule 32222 is configured to alternately output the upper threshold voltage and the lower threshold voltage of the target voltage range to the comparator 32221. The comparator 32221 is configured to compare the detection voltage V1 and the upper threshold voltage, in the case that the detection voltage V1 and the upper threshold voltage are received, to output an overcurrent fault signal to the processing submodule 32222, in the case that the detection voltage V1 is greater than the upper threshold voltage, and output a normal working signal to the processing submodule 32222, in the case that the detection voltage V1 is less than or equal to the upper threshold voltage.

[0101] The comparator 32221 is further configured to, in a case of receiving the detection voltage V1 and the lower threshold voltage, compare the detection voltage V1 with the lower threshold voltage, and output an overcurrent fault signal to the processing submodule 32222 in a case that the detection voltage V1 is less than the lower threshold voltage, or output a normal working signal to the processing submodule 32222 in a case that the detection voltage V1 is greater than or equal to the lower threshold voltage.

[0102] The processing submodule 32222 is configured to output the overcurrent fault signal to the control unit 321 in a case of receiving the overcurrent fault signal, or output the normal working signal to the control unit 321 in a case of not receiving the overcurrent fault signal.

[0103] For example, please continue to refer to Figure 6 The comparator 32221 can include an operational amplifier U1. A first input terminal of the operational amplifier U1 is connected with the current detection module 3221, for receiving the detection voltage V1. A second input terminal of the operational amplifier U1 is connected with the processing submodule 32222, for receiving the upper threshold voltage or the lower threshold voltage of the target voltage range. An output terminal of the operational amplifier U1 is also connected with the processing submodule 32222.

[0104] The operational amplifier U1 is configured to compare the detection voltage V1 with the upper threshold voltage, and compare the detection voltage V1 with the lower threshold voltage, and output the overcurrent fault signal to the processing submodule 32222 in a case that the detection voltage V1 is greater than the upper threshold voltage, or the detection voltage V1 is less than the lower threshold voltage. The operational amplifier U1 is further configured to output the normal working signal to the processing submodule 32222 in a case that the detection voltage V1 is less than or equal to the upper threshold voltage, or the detection voltage V1 is greater than or equal to the lower threshold voltage.

[0105] For further example, please continue to refer to Figure 6 The comparator 32221 can include a second resistor R2 and a first capacitor C1. A first terminal of the second resistor R2 is connected with the current detection module 3221, and a second terminal of the second resistor R2 is connected with the first input terminal of the operational amplifier U1 and a first terminal of the first capacitor C1. A second terminal of the first capacitor C1 is grounded. The first input terminal of the operational amplifier U1 is connected with the current detection module 3221, for receiving the detection voltage V1. The second input terminal of the operational amplifier U1 is connected with the processing submodule 32222 and the output terminal of the operational amplifier U1, for receiving the upper threshold voltage or the lower threshold voltage of the target voltage range. The output terminal of the operational amplifier U1 is also connected with the processing submodule 32222.

[0106] For another example, please continue to refer to Figure 6The processing submodule 32222 can be a comparator chip U2. A first pin PIN1 of the comparator chip U2 is connected with the second input end of the operational amplifier U1, for outputting the upper threshold voltage or the lower threshold voltage of the target voltage range to the operational amplifier U1. A second pin PIN2 of the comparator chip U2 is connected with the output end of the operational amplifier U1, for receiving the normal working signal or the overcurrent fault signal output by the operational amplifier U1. A third pin PIN3 of the comparator chip U2 is connected with the control unit 321, for outputting the normal working signal or the overcurrent fault signal to the control unit 321.

[0107] In the embodiments of the present application, the current detection module 3221 is configured to collect the output current of the phase current output end, and convert the output current into a detection voltage V1, and output the detection voltage V1 to the comparison module 3222. Optionally, as shown in Figure 6 the current detection module 3221 includes a current sensor. The current sensor is connected with the phase current output end and the comparison module 3222. The current sensor is configured to collect the output current of the phase current output end, and convert the output current into a detection voltage, and output the detection voltage to the comparison module 3222.

[0108] In some embodiments of the present application, as shown in Figure 5 the detection unit 322 can further include a voltage conversion module 3223.

[0109] The voltage conversion module 3223 is connected with the current detection module 3221 and the comparison module 3222. The voltage conversion module 3223 is configured to receive the detection voltage output by the current detection module 3221, and output the detection voltage to the comparison module 3222 after impedance conversion. By performing impedance conversion on the detection voltage output by the current detection module 3221, the voltage conversion module 3223 can match the impedance difference between the input circuit and the output circuit, thereby effectively improving the signal transmission efficiency and quality, and improving the circuit performance and operation reliability.

[0110] Optionally, as shown in Figure 6 the voltage conversion module 3223 can include a voltage follower. The voltage follower is connected with the current detection module 3221 and the comparison module 3222. The voltage follower is configured to output the detection voltage to the comparison module 3222 after impedance conversion. For example, as shown in Figure 6 the voltage follower in the voltage conversion module 3223 includes an operational amplifier U3, a third resistor R3, a fourth resistor R4, a second capacitor C2 and a third capacitor C3.

[0111] The first input terminal of the operational amplifier U3 is connected with the output terminal of the operational amplifier U3. The second input terminal of the operational amplifier U3 is connected with the current detection module 3221 through the third resistor R3. The output terminal of the operational amplifier U3 is connected with the comparison module 3222. The first power supply terminal of the operational amplifier U3 is connected with the first power supply terminal VDD1 and one end of the third capacitor C3 respectively, and the other end of the third capacitor C3 is grounded. In addition, the first end of the fourth resistor R4 is also connected with the connection path between the third resistor R3 and the operational amplifier U3, and the second end of the fourth resistor R4 is grounded. The first end of the second capacitor C2 is also connected with the connection path between the third resistor R3 and the operational amplifier U3, and the second end of the second capacitor C2 is grounded.

[0112] As shown in some embodiments of the present application, Figure 5 The detection unit 322 can further include a clamping module 3224.

[0113] The clamping module 3224 is connected with the current detection module 3221 and the motor control unit (MCU) 12. The clamping module 3224 is configured to receive the detection voltage output by the current detection module 3221, clamp the detection voltage to an input voltage range of the motor control unit 12, obtain a controller detection voltage, and output the controller detection voltage to the motor control unit 12. Specifically, the input voltage range of the motor control unit 12 is 0-3V. The clamping module 3224 is configured to receive the detection voltage output by the current detection module 3221, clamp the detection voltage to 0-3V, obtain the controller detection voltage, and output the controller detection voltage to the motor control unit 12.

[0114] The motor control unit 12 is configured to control the motor control circuit 11 to connect or disconnect the motor power supply Vcd and the motor 2 according to the controller detection voltage. Specifically, the motor control unit 12 can be configured to execute a software overcurrent protection strategy according to the controller detection voltage to control the motor control circuit 11 to connect or disconnect the motor power supply Vcd and the motor 2.

[0115] Optionally, please refer to Figure 6The clamping module 3224 includes a fifth resistor R5, a fourth capacitor C4, a second diode D2, and a third diode D3. The first end of the fifth resistor R5 is connected with the current detection module 3221, and the second end of the fifth resistor R5 is connected with the MCU 12. The first end of the fourth capacitor C4 is connected with the connection path between the fifth resistor R5 and the MCU 12, and the second end of the fourth capacitor C4 is grounded. The cathode of the second diode D2 is connected with the connection path between the fifth resistor R5 and the MCU 12, and the anode of the second diode D2 is grounded. The anode of the third diode D3 is connected with the connection path between the fifth resistor R5 and the MCU 12, and the cathode of the third diode D3 is connected with the second power supply end VDD2. The second power supply end VDD2 is used to supply power to the cathode of the third diode D3.

[0116] In some embodiments, the detection voltage output by the current detection module 3221 can be clamped to the input voltage range of the motor controller 12 through the clamping module 3224, so that the overcurrent protection of the motor control circuit 11 can be realized by using a series of hardware circuits such as the comparison module 3222, the control unit 321, and the on-off control circuit 31, and at the same time, the controller detection voltage of the motor 2 that can be accepted by the motor controller 12 can be transmitted, so that the motor controller 12 can execute the software overcurrent protection strategy according to the received controller detection voltage, realize the double overcurrent protection of the motor control circuit 11, and effectively improve the overcurrent protection effect of the motor control circuit 11.

[0117] In some embodiments, as shown in Figure 5 The overcurrent control circuit 32 includes a control unit 321 and three detection units 322. The structure of each detection unit 322 is the same, and the structure of one detection unit 322 is taken as an example for illustrative description. The detection unit 322 includes a current detection module 3221, a comparison module 3222, a voltage conversion module 3223, and a clamping module 3224.

[0118] The current detection module 3221 is connected with the first-phase current output end A of the motor 2 and the voltage conversion module 3223, used to collect the output current of the first-phase current output end A and convert the output current into a detection voltage V1, and output the detection voltage V1 to the voltage conversion module 3223.

[0119] The voltage conversion module 3223 is connected with the clamping module 3224 and the comparison module 3222, used to receive the detection voltage V1 output by the current detection module 3221, and output the detection voltage V1 after impedance conversion to the clamping module 3224 and the comparison module 3222.

[0120] The clamping module 3224 is connected with the MCU 12, used for receiving the detection voltage output by the current detection module 3221, clamping the detection voltage to the input voltage range of the MCU 12, obtaining a controller detection voltage, and outputting the controller detection voltage to the MCU 12, so that the MCU 12 is used to execute a software overcurrent protection strategy according to the controller detection voltage, to control the motor control circuit 11 to connect or disconnect the motor power supply Vcd and the motor 2.

[0121] The comparison module 3222 is connected with the control unit 321, used for outputting an overcurrent fault signal to the control unit 321 in the case that the detection voltage V1 exceeds the target voltage range, and outputting a normal working signal to the control unit 321 in the case that the detection voltage V1 does not exceed the target voltage range.

[0122] The control unit 321 can be used to control the target relay S to disconnect the connection between the motor control circuit 11 connected with the target relay S and the phase current output end in the case that the overcurrent fault signal is received. In an optional case, the target relay S is a relay S connected with a target output end. The output current of the target output end corresponds to a detection voltage exceeding the target voltage range. In another optional case, the target relay S is all the relays S in the three on-off control units 311.

[0123] In the embodiment of the application, the motor control circuit and the motor are connected in isolation through the on-off control circuit. The overcurrent control circuit is used to collect a detection voltage corresponding to the output current of the motor, and in the case that the detection voltage exceeds the target voltage range, indicating that the motor has an overcurrent output and the motor control circuit has an overcurrent damage risk, the on-off control circuit can be controlled to disconnect the connection between the motor control circuit and the motor, so that the motor stops working. Since the on-off control circuit can isolate the motor control circuit and the motor after disconnecting the motor control circuit and the motor, there is no electrical connection between the motor control circuit and the motor. Therefore, the backflow of the counter electromotive force current generated by the motor when it stops working to the motor control circuit can be effectively prevented, and the overcurrent protection of the motor control circuit can be effectively realized, and the device damage problem of the motor control circuit due to the overcurrent risk can be prevented.

[0124] In order to further understand the technical solutions of the application, the motor overcurrent protection circuit provided by the embodiment of the application is further described below. As shown in Figure 7 The motor overcurrent protection circuit 3 includes an on-off control circuit 31 and an overcurrent control circuit 32. The on-off control circuit 31 includes a first on-off control unit 311, a second on-off control unit 311, and a third on-off control unit 311.

[0125] In the first on / off control unit 311, relay S is connected to the motor control circuit 11, the overcurrent control circuit 32, and the first phase current output terminal A of the motor 2. Furthermore, in the first on / off control unit 311, the cathode of the first diode D1 is connected to the first phase current output terminal A through the first resistor R1, and the anode of the first diode D1 is connected to the motor control circuit 11.

[0126] In the second on / off control unit 311, relay S is connected to the motor control circuit 11, the overcurrent control circuit 32, and the second phase current output terminal B of the motor 2. Furthermore, in the second on / off control unit 311, the cathode of the first diode D1 is connected to the first phase current output terminal A through the first resistor R1, and the anode of the first diode D1 is connected to the motor control circuit 11.

[0127] In the third on / off control unit 311, relay S is connected to the motor control circuit 11, the overcurrent control circuit 32, and the third phase current output terminal C of the motor 2. Furthermore, in the third on / off control unit 311, the cathode of the first diode D1 is connected to the first phase current output terminal A through the first resistor R1, and the anode of the first diode D1 is connected to the motor control circuit 11.

[0128] The overcurrent control circuit 32 includes a control unit 321 and three detection units 322. The three detection units 322 include a first detection unit 322, a second detection unit 322, and a third detection unit 322. The first detection unit 322 is connected to the control unit 321 and the first phase current output terminal A of the motor 2. The second detection unit 322 is connected to the control unit 321 and the second phase current output terminal B of the motor 2. The third detection unit 322 is connected to the control unit 321 and the third phase current output terminal C of the motor 2.

[0129] Each detection unit 322 has the same structure. Taking the structure of the first detection unit 322 as an example, the diagram is illustrated. The current detection module 3221 in the first detection unit 322 includes a current sensor, which is used to collect the output current of the first phase current output terminal, convert the output current into a detection voltage, and output the detection voltage to the voltage conversion module 3223.

[0130] The voltage conversion module 3223 in the first detection unit 322 includes a voltage follower. The voltage follower includes an operational amplifier U3, a third resistor R3, a fourth resistor R4, a second capacitor C2 and a third capacitor C3. The first input terminal of the operational amplifier U3 is connected with the output terminal of the operational amplifier U3. The second input terminal of the operational amplifier U3 is connected with the current detection module 3221 through the third resistor R3. The output terminal of the operational amplifier U3 is connected with the comparison module 3222. The first power supply terminal of the operational amplifier U3 is connected with the first power supply terminal VDD1 and one end of the third capacitor C3 respectively, and the other end of the third capacitor C3 is grounded. In addition, the first end of the fourth resistor R4 is also connected with the connection path between the third resistor R3 and the operational amplifier U3, and the second end of the fourth resistor R4 is grounded. The first end of the second capacitor C2 is also connected with the connection path between the third resistor R3 and the operational amplifier U3, and the second end of the second capacitor C2 is grounded. The operational amplifier U3 is used to convert the detection voltage V1 to impedance and output to the clamping module 3224 and the comparison module 3222.

[0131] The clamping module 3224 in the first detection unit 322 includes a fifth resistor R5, a fourth capacitor C4, a second diode D2 and a third diode D3. The first end of the fifth resistor R5 is connected with the output terminal of the operational amplifier U3, and the second end of the fifth resistor R5 is connected with the MCU 12. The first end of the fourth capacitor C4 is connected with the connection path between the fifth resistor R5 and the MCU 12, and the second end of the fourth capacitor C4 is grounded. The cathode of the second diode D2 is connected with the connection path between the fifth resistor R5 and the MCU 12, and the anode of the second diode D2 is grounded. The anode of the third diode D3 is connected with the connection path between the fifth resistor R5 and the MCU 12, and the cathode of the third diode D3 is connected with the second power supply terminal VDD2. The second power supply terminal VDD2 is used to supply power to the cathode of the third diode D3. The fifth resistor R5, the fourth capacitor C4, the second diode D2 and the third diode D3 cooperate to clamp the detection voltage to the input voltage range of the MCU 12, obtain the controller detection voltage, and output the controller detection voltage to the MCU 12. The MCU 12 is used to execute the software overcurrent protection strategy according to the controller detection voltage, so as to control the motor control circuit 11 to connect or disconnect the motor power supply Vcd and the motor 2.

[0132] The comparison module 3222 in the first detection unit 322 includes an operational amplifier U1, a second resistor R2, a first capacitor C1 and a comparator chip U2. Taking the comparator chip U2 as an example, the comparator chip U2 is an LM2903 chip. The comparison module 3222 further includes a sixth resistor R6 to a thirteenth resistor R13, and a fifth capacitor C5 and a sixth capacitor C6.

[0133] The first end of the second resistor R2 is connected with the output end of the operational amplifier U3, and the second end of the second resistor R2 is connected with the first input end of the operational amplifier U1 and the first end of the first capacitor C1. The second end of the first capacitor C1 is grounded. The first input end of the operational amplifier U1 is connected with the output end of the operational amplifier U3 for receiving the detection voltage V1. The second input end of the operational amplifier U1 is connected with the processing sub-module 32222 and the output end of the operational amplifier U1 for receiving the upper limit threshold voltage or the lower limit threshold voltage of the target voltage range. The output end of the operational amplifier U1 is also connected with the processing sub-module 32222.

[0134] The pin 10 OUT of the LM2903 chip is connected with the output end of the operational amplifier U1 through the sixth resistor R6 for receiving the overcurrent fault signal or the normal working signal output by the operational amplifier U1. The pin 1 IN- of the LM2903 chip is connected with the first end of the seventh resistor R7, the first end of the eighth resistor R8 and the first end of the fifth capacitor C5 respectively. The second end of the seventh resistor R7 is connected with the third power supply end VDD3 for providing +5V power supply signal. The second end of the eighth resistor R8 and the second end of the fifth capacitor C5 are grounded. The pin 1 IN+ (i.e. the second pin PIN2) of the LM2903 chip is connected with the connection path between the sixth resistor R6 and the pin 10 OUT through the ninth resistor R9. The pin GND of the LM2903 chip is grounded. The pin VCC of the LM2903 chip is connected with the fourth power supply end VDD4 and the first end of the sixth capacitor C6 respectively, and the second end of the sixth capacitor C6 is grounded. The pin 2 OUT (i.e. the third pin PIN3) of the LM2903 chip is connected with the control unit 321 through the tenth resistor R10. The pin 2 IN- (i.e. the first pin PIN1) of the LM2903 chip is connected with the second input end of the operational amplifier U1 for outputting the upper limit threshold voltage or the lower limit threshold voltage of the target voltage range to the operational amplifier U1. The pin 2 IN+ of the LM2903 chip is connected with the control unit 321 and the first end of the eleventh resistor R11. The second end of the eleventh resistor R11 is connected with the first end of the twelfth resistor R12, and the second end of the twelfth resistor is connected with the fifth power supply end VDD5. The first end of the seventh capacitor C7 is connected with the connection path between the eleventh resistor R11 and the twelfth resistor R12, and the second end of the seventh capacitor C7 is grounded. The first end of the thirteenth resistor R13 is connected with the connection path between the eleventh resistor R11 and the twelfth resistor R12, and the second end of the thirteenth resistor R13 is grounded.

[0135] The control unit 321 is a programmable control chip 321 connected with the relays S in the first on-off control unit 311, the second on-off control unit 311 and the third on-off control unit 311.

[0136] In the motor overcurrent protection circuit 3, the current sensor in the first detection unit 322 (or the second detection unit 322, or the third detection unit 322) is used to collect the detection voltage V1 corresponding to the output current of the first phase current output terminal A (or the second phase current output terminal B, or the third phase current output terminal C). The voltage follower is used to perform impedance transformation on the detection voltage V1 and output it to the clamping module 3224 and the comparison module 3222. The clamping module 3224 is used to clamp the detection voltage to within 0-3V to obtain the controller detection voltage, and output the controller detection voltage to the MCU 12 so that the MCU 12 can execute the software overcurrent protection strategy according to the controller detection voltage to control the motor control circuit 11 to connect or disconnect the motor power supply Vcd and the motor 2.

[0137] The comparison module 3222 is used to output an overcurrent fault signal to the control unit 321 when the detected voltage V1 exceeds the target voltage range.

[0138] In some embodiments of this application, the comparison module 3222 is used to receive the detection circuit V1 transmitted by the voltage follower and compare the detected voltage V1 with the upper threshold voltage of the target voltage range and the lower threshold voltage of the target voltage range.

[0139] The comparison module 3222 is used to determine that the detected voltage V1 does not exceed the target voltage range and the output current of the motor 2 is within the normal current range when the detected voltage V1 is greater than or equal to the lower threshold voltage and less than or equal to the upper threshold voltage, and then outputs a normal operation signal to the control unit 321. The control unit 321, upon receiving the normal operation signal, outputs a connection control signal to the target relay S. The target relay S, upon receiving the connection control signal, connects the motor control circuit 11 to its connected phase current output terminal.

[0140] The comparison module 3222 is further configured to determine that the detected voltage V1 exceeds the target voltage range and the output current of the motor 2 exceeds the normal current range when the detected voltage V1 is less than the lower threshold voltage or greater than the upper threshold voltage, and then output an overcurrent fault signal to the control unit 321. The control unit 321, upon receiving the overcurrent fault signal, outputs a disconnect control signal to the target relay S. The target relay S, upon receiving the disconnect control signal, disconnects the connection between its connected motor control circuit 11 and the phase current output terminal. Optionally, the target relay S is a relay S connected to the target output terminal. The detected voltage corresponding to the output current of the target output terminal exceeds the target voltage range. Alternatively, the target relay S is all relays S in the three on / off control units 311.

[0141] In the embodiment of the present application, the motor control circuit and the motor are connected in isolation through the on-off control circuit. The overcurrent control circuit is used to collect the detection voltage corresponding to the output current of the motor, and in the case that the detection voltage exceeds the target voltage range, indicating that the motor has overcurrent output and the motor control circuit has overcurrent damage risk, the on-off control circuit can be controlled to disconnect the connection between the motor control circuit and the motor, so as to stop the motor from working. After the on-off control circuit disconnects the motor control circuit and the motor, the motor control circuit and the motor can be isolated, so that there is no electrical connection between the motor control circuit and the motor. Therefore, the backflow of the counter electromotive force current generated by the motor when it stops working into the motor control circuit can be effectively prevented, and the overcurrent protection of the motor control circuit is effectively realized, and the device damage problem of the motor control circuit caused by overcurrent risk is prevented.

[0142] The embodiment of the present application also provides a controller. The controller comprises the motor overcurrent protection circuit provided by the embodiment of the present application. In the controller provided by the embodiment of the present application, the motor control circuit and the motor are connected in isolation through the on-off control circuit. The overcurrent control circuit is used to collect the detection voltage corresponding to the output current of the motor, and in the case that the detection voltage exceeds the target voltage range, indicating that the motor has overcurrent output and the motor control circuit has overcurrent damage risk, the on-off control circuit can be controlled to disconnect the connection between the motor control circuit and the motor, so as to stop the motor from working. After the on-off control circuit disconnects the motor control circuit and the motor, the motor control circuit and the motor can be isolated, so that there is no electrical connection between the motor control circuit and the motor. Therefore, the backflow of the counter electromotive force current generated by the motor when it stops working into the motor control circuit can be effectively prevented, and the overcurrent protection of the motor control circuit is effectively realized, and the device damage problem of the motor control circuit caused by overcurrent risk is prevented.

[0143] The embodiment of the present application also provides a vehicle. The vehicle comprises the controller provided by the embodiment of the present application. In the vehicle provided by the embodiment of the present application, the motor control circuit and the motor are connected in isolation through the on-off control circuit. The overcurrent control circuit is used to collect the detection voltage corresponding to the output current of the motor, and in the case that the detection voltage exceeds the target voltage range, indicating that the motor has overcurrent output and the motor control circuit has overcurrent damage risk, the on-off control circuit can be controlled to disconnect the connection between the motor control circuit and the motor, so as to stop the motor from working. After the on-off control circuit disconnects the motor control circuit and the motor, the motor control circuit and the motor can be isolated, so that there is no electrical connection between the motor control circuit and the motor. Therefore, the backflow of the counter electromotive force current generated by the motor when it stops working into the motor control circuit can be effectively prevented, and the overcurrent protection of the motor control circuit is effectively realized, and the device damage problem of the motor control circuit caused by overcurrent risk is prevented.

[0144] In the embodiments described above, all or some of the steps can be implemented by software, hardware or firmware, or any combination thereof. When implemented by software, all or some of the steps can be implemented in the form of one or more computer programs. The computer program can be stored in any computer readable medium, and when loaded into a computer system, causes the computer system to perform one or more of the steps of the computer program. The computer readable medium can be a magnetic disk, an optical disk or a solid state drive, or any combination thereof. The computer readable medium can be distributed to computer systems connected by a network, so that the computer programs that constitute the computer programs (which can also be in the form of computer readable medium) can be stored in and executed by the network connected computer systems in a distributed manner.

[0145] It should be noted that, in the present document, the terms such as first and second are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Also, the terms "comprising", "containing" or any other variant thereof are intended to cover a non-exclusive inclusion, so that a process, method, article or apparatus that comprises a list of elements does not only include those elements, but also other elements not expressly listed or inherent to such process, method, article or apparatus. Without more limitations, an element defined by the phrase "comprising a" does not exclude the presence of additional identical elements in the process, method, article or apparatus that includes the element.

[0146] Each of the embodiments in the present specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the difference from other embodiments. For the embodiments of the apparatus, electronic device, computer readable storage medium and computer program product containing instructions thereof, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the part of the method embodiments.

[0147] The above merely provides preferred embodiments of the application, and not for limiting the protective scope of the application. Any modification, equivalent replacement, improvement, etc. made within the principle and technical scope of the application shall fall into the protective scope of the application.

Claims

1. A motor overcurrent protection circuit, characterized in that, The motor overcurrent protection circuit includes: an on / off control circuit and an overcurrent control circuit; The on / off control circuit is connected to the motor control circuit, the motor, and the overcurrent control circuit, and is used to connect or disconnect the motor control circuit and the motor under the control of the overcurrent control circuit. The overcurrent control circuit is connected to the motor and is used to collect the detection voltage corresponding to the output current of the motor. When the detection voltage exceeds the target voltage range, the on / off control circuit is controlled to disconnect the connection between the motor control circuit and the motor. The overcurrent control circuit includes: a control unit and three detection units; each detection unit includes: a current detection module and a comparison module; the detection unit further includes: a voltage conversion module; The voltage conversion module includes: a voltage follower; The voltage follower is connected to the current detection module and the comparison module, and is used to perform impedance conversion on the detected voltage and output it to the comparison module.

2. The motor overcurrent protection circuit according to claim 1, characterized in that, The on / off control circuit includes: at least one on / off control unit; Each of the on / off control units is connected to the motor control circuit, the overcurrent control circuit, and the phase current output terminal of the motor, and is used to connect or disconnect the phase current output terminal and the motor control circuit under the control of the overcurrent control circuit.

3. The motor overcurrent protection circuit according to claim 2, characterized in that, The on / off control circuit includes: three on / off control units; Each of the on / off control units is connected to the motor control circuit, the overcurrent control circuit, and a different phase current output terminal of the motor.

4. The motor overcurrent protection circuit according to claim 2 or 3, characterized in that, The on / off control circuit includes: an isolation switch device; The isolating switch is connected to the motor control circuit, the overcurrent control circuit, and the phase current output terminal, and is used to connect or disconnect the phase current output terminal and the motor control circuit under the control of the overcurrent control circuit.

5. The motor overcurrent protection circuit according to claim 4, characterized in that, The isolating switch device includes: a relay; The relay is connected to the motor control circuit, the overcurrent control circuit, and the phase current output terminal, and is used to connect or disconnect the phase current output terminal and the motor control circuit under the control of the overcurrent control circuit.

6. The motor overcurrent protection circuit according to claim 4, characterized in that, The on / off control unit further includes: a flow-blocking component; The current-blocking component is connected in parallel with the isolating switch device and is used to prevent the output signal of the phase current output terminal from flowing to the motor control circuit when the isolating switch device disconnects the phase current output terminal and the motor control circuit.

7. The motor overcurrent protection circuit according to claim 6, characterized in that, The current-blocking component includes a first resistor, which is connected in parallel with the isolating switch device.

8. The motor overcurrent protection circuit according to claim 6, characterized in that, The current-blocking component includes: a first diode, the cathode of the first diode being connected to the phase current output terminal, and the anode of the first diode being connected to the motor control circuit.

9. The motor overcurrent protection circuit according to claim 6, characterized in that, The current-blocking component includes: a first resistor and a first diode; The cathode of the first diode is connected to the phase current output terminal through the first resistor, and the anode of the first diode is connected to the motor control circuit. Alternatively, the cathode of the first diode is connected to the phase current output terminal, and the anode of the first diode is connected to the motor control circuit through the first resistor.

10. The motor overcurrent protection circuit according to any one of claims 1 to 9, characterized in that, Each of the detection units is connected to the control unit and a different phase current output terminal of the motor, and is used to collect the detection voltage corresponding to the output current of the phase current output terminal. If the detection voltage exceeds the target voltage range, an overcurrent fault signal is output to the control unit. The control unit is used to receive the overcurrent fault signal and control the on / off control circuit to at least disconnect the connection between the motor control circuit and the target output terminal of the motor, wherein the detection voltage corresponding to the output current of the target output terminal exceeds the target voltage range.

11. The motor overcurrent protection circuit according to claim 10, characterized in that, The current detection module is connected to the phase current output terminal and the comparison module, and is used to collect the output current of the phase current output terminal, convert the output current into a detection voltage, and output the detection voltage to the comparison module. The comparison module is connected to the control unit and is used to output an overcurrent fault signal to the control unit when the detected voltage exceeds the target voltage range.

12. The motor overcurrent protection circuit according to claim 11, characterized in that, The current detection module includes: a current sensor; The current sensor is connected to the phase current output terminal and the comparison module, and is used to collect the output current of the phase current output terminal, convert the output current into a detection voltage, and output the detection voltage to the comparison module.

13. The motor overcurrent protection circuit according to claim 11, characterized in that, The comparison module includes: a comparator and a processing submodule; The processing submodule is connected to the comparator and is used to provide the comparator with the upper threshold voltage and the lower threshold voltage of the target voltage range; The comparator is connected to the current detection module and is used to receive the detection voltage. If the detection voltage is less than the lower threshold voltage or greater than the upper threshold voltage, the comparator outputs an overcurrent fault signal to the processing submodule. The processing submodule is connected to the control unit and is used to receive the overcurrent fault signal output by the comparator and output the overcurrent fault signal to the control unit.

14. The motor overcurrent protection circuit according to claim 11, characterized in that, The voltage conversion module is connected to the current detection module and the comparison module, and is used to receive the detection voltage output by the current detection module, and output the detection voltage to the comparison module after impedance conversion.

15. The motor overcurrent protection circuit according to claim 11, characterized in that, The detection unit further includes: a clamping module; The clamping module is connected to the current detection module and the motor controller, and is used to receive the detection voltage output by the current detection module, clamp the detection voltage to the input voltage range of the motor controller to obtain the controller detection voltage, and output the controller detection voltage to the motor controller. The motor controller is used to control the motor control circuit to connect or disconnect the motor power supply and the motor based on the voltage detected by the controller.

16. A controller, characterized in that, The controller includes the motor overcurrent protection circuit as described in any one of claims 1 to 15.

17. A vehicle, characterized in that, The vehicle includes the controller as described in claim 16.

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