An isolation detection circuit

Abstract

This invention discloses an isolation detection circuit. The isolation detection circuit includes: a control unit, a battery module, an energy storage converter, a first control circuit, and a second control circuit. The first control circuit includes a first optocoupler, a first MOSFET, and a first resistor. The second control circuit includes a second optocoupler, a second MOSFET, a second resistor, and a third resistor. The control unit is used to determine the voltage of the battery module and perform insulation and adhesion detection on the battery module through the first and second control circuits. The isolation detection circuit provided by this invention can achieve voltage acquisition, insulation detection, and adhesion detection while maintaining circuit isolation.

Description

Technical Field

[0001] This invention relates to battery detection technology, and more particularly to an isolation detection circuit. Background Technology

[0002] For batteries such as battery modules, a battery management system (BMS) is typically required for their management and control. The control unit within the BMS can detect and control the battery module. If the circuit isolation between the control unit and the battery module is inadequate, it will affect the detection and control results. Therefore, effective isolation between the battery module and the control unit is necessary.

[0003] Currently, existing isolation detection circuits typically only perform single-function tests on battery modules, such as voltage acquisition or insulation testing. These tests are limited in function and lack comprehensive functionality, failing to form integrated circuits or modules that can achieve comprehensive testing of battery modules. Summary of the Invention

[0004] This invention provides an isolation detection circuit to achieve voltage acquisition, insulation detection, and adhesion detection while isolating the circuit.

[0005] This invention provides an isolation detection circuit, comprising: a control unit, a battery module, an energy storage converter, a first control circuit, and a second control circuit;

[0006] The first control circuit includes a first optocoupler, a first MOSFET, and a first resistor. The first terminal of the first optocoupler is electrically connected to the power supply, the second terminal of the first optocoupler is electrically connected to the first electrode of the first MOSFET, the third terminal of the first optocoupler is electrically connected to the first signal terminal of the control unit, the fourth terminal of the first optocoupler is electrically connected to the first terminal of the first resistor, the second terminal of the first resistor is electrically connected to the positive terminal of the energy storage converter, the gate of the first MOSFET is electrically connected to the first converter control terminal of the control unit, and the second electrode of the first MOSFET is grounded.

[0007] The second control circuit includes a second optocoupler, a second MOSFET, a second resistor, and a third resistor. The first terminal of the second optocoupler is electrically connected to the power supply, the second terminal of the second optocoupler is electrically connected to the first electrode of the second MOSFET, the third terminal of the second optocoupler is electrically connected to the positive electrode of the battery module through the second resistor, the fourth terminal of the second optocoupler is electrically connected to the first signal terminal of the control unit, the fourth terminal of the second optocoupler is electrically connected to the first terminal of the third resistor, the second terminal of the third resistor is electrically connected to the reference voltage terminal of the control unit, the gate of the second MOSFET is electrically connected to the first battery module control terminal of the control unit, and the second electrode of the second MOSFET is grounded.

[0008] The control unit is used to determine the voltage of the battery module and perform insulation and adhesion detection on the battery module through the first control circuit and the second control circuit.

[0009] Optionally, the above-mentioned isolation detection circuit further includes a third control circuit, which includes a third optocoupler, a third MOSFET, and a fourth resistor. The first end of the third optocoupler is electrically connected to the power supply, the second end of the third optocoupler is electrically connected to the first electrode of the third MOSFET, the third end of the third optocoupler is electrically connected to the second signal terminal of the control unit, the fourth end of the third optocoupler is electrically connected to the first end of the fourth resistor, the second end of the fourth resistor is electrically connected to the negative terminal of the energy storage converter, the gate of the third MOSFET is electrically connected to the second converter control terminal of the control unit, and the second electrode of the third MOSFET is grounded.

[0010] Optionally, the above-mentioned isolation detection circuit further includes a first diode and a second diode. The second end of the first resistor is electrically connected to the negative terminal of the energy storage converter through the first diode, and the second end of the fourth resistor is electrically connected to the positive terminal of the energy storage converter through the second diode. Specifically, the positive terminal of the first diode is electrically connected to the positive terminal of the energy storage converter, the negative terminal of the first diode is electrically connected to the second end of the first resistor, the positive terminal of the second diode is electrically connected to the negative terminal of the energy storage converter, and the negative terminal of the second diode is electrically connected to the second end of the fourth resistor.

[0011] Optionally, the second control circuit further includes a fourth optocoupler, a fourth MOSFET, a fifth resistor, and a sixth resistor. The first terminal of the fourth optocoupler is electrically connected to the power supply, the second terminal of the fourth optocoupler is electrically connected to the first electrode of the fourth MOSFET, the third terminal of the fourth optocoupler is electrically connected to the negative electrode of the battery module through the fifth resistor, the fourth terminal of the fourth optocoupler is electrically connected to the second signal terminal of the control unit, the fourth terminal of the fourth optocoupler is electrically connected to the second terminal of the third resistor through the sixth resistor, the gate of the fourth MOSFET is electrically connected to the second battery module control terminal of the control unit, and the second electrode of the fourth MOSFET is grounded.

[0012] Optionally, the second control circuit also includes a fifth optocoupler and a fifth MOSFET. The first terminal of the fifth optocoupler is electrically connected to the power supply, the second terminal of the fifth optocoupler is electrically connected to the first electrode of the fifth MOSFET, the third terminal of the fifth optocoupler is grounded, the fourth terminal of the fifth optocoupler is electrically connected to the second terminal of the third resistor, the gate of the fifth MOSFET is electrically connected to the ground control terminal of the control unit, and the second electrode of the fifth MOSFET is grounded.

[0013] Optionally, the second control circuit also includes a seventh resistor and a first inductor. The second terminal of the fifth optocoupler is electrically connected to the first terminal of the fifth MOS transistor through the seventh resistor, and the third terminal of the fifth optocoupler is grounded through the first inductor.

[0014] Optionally, the above-mentioned isolation detection circuit further includes a first contactor and a second contactor. The positive terminal of the battery module is electrically connected to the positive terminal of the energy storage converter through the first contactor, and the negative terminal of the battery module is electrically connected to the negative terminal of the energy storage converter through the second contactor. The control unit is specifically used to detect whether the first contactor is stuck and whether the second contactor is stuck.

[0015] Optionally, the above-mentioned isolation detection circuit also includes a power isolation element, and the power control interface of the control unit is electrically connected to the power isolation element.

[0016] Optionally, the control unit includes a controller and a signal acquisition element. The controller is electrically connected to the signal acquisition element. The first voltage output terminal of the power isolation element is electrically connected to the first voltage input terminal of the signal acquisition element. The second voltage output terminal of the power isolation element is electrically connected to the second voltage input terminal of the signal acquisition element. The signal acquisition element is used to acquire voltage signals and convert the voltage signals into communication signals.

[0017] The power control interface of the controller serves as the power control interface of the control unit. The first signal terminal, the second signal terminal, and the reference voltage terminal of the signal acquisition element serve as the first signal terminal, the second signal terminal, and the reference voltage terminal of the control unit, respectively. The first inverter control terminal, the second inverter control terminal, the first battery module control terminal, and the second battery module control terminal of the controller serve as the first inverter control terminal, the second inverter control terminal, the first battery module control terminal, and the second battery module control terminal of the control unit, respectively.

[0018] Optionally, the control unit also includes a communication isolation element. The controller and the signal acquisition element are electrically connected through the communication isolation element, which is used to transmit communication signals to the controller and also to transmit control signals from the controller to the signal acquisition element.

[0019] The isolation detection circuit provided in this embodiment of the invention includes a control unit, a battery module, an energy storage converter, a first control circuit, and a second control circuit. The first control circuit includes a first optocoupler, a first MOSFET, and a first resistor. The second control circuit includes a second optocoupler, a second MOSFET, a second resistor, and a third resistor. The control unit is used to determine the voltage of the battery module and perform insulation and adhesion detection on the battery module through the first and second control circuits. The isolation detection circuit provided in this embodiment of the invention can control the connection state between the battery module and the control unit through the first control circuit, and can control the connection state between the energy storage converter and the control unit through the second control circuit, realizing time-sharing control of the battery module and the energy storage converter. Based on isolating the control unit from the battery module and the energy storage converter, it achieves voltage acquisition, insulation detection, and adhesion detection. Attached Figure Description

[0020] Figure 1This is a schematic diagram of an isolation detection circuit provided in an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of a partial structure of an isolation detection circuit provided in an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of a partial structure of another isolation detection circuit provided in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of a partial structure of another isolation detection circuit provided in an embodiment of the present invention. Detailed Implementation

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0025] Figure 1 This is a schematic diagram of an isolation detection circuit provided in an embodiment of the present invention. This embodiment can be applied to situations such as detecting battery modules. The isolation detection circuit includes: a control unit 10, a battery module 20, an energy storage converter 30, a first control circuit 40, and a second control circuit 50.

[0026] The first control circuit includes a first optocoupler U1, a first MOSFET Q1, and a first resistor R1. The first terminal of the first optocoupler U1 is electrically connected to the power supply, the second terminal of the first optocoupler U1 is electrically connected to the first electrode of the first MOSFET Q1, the third terminal of the first optocoupler U1 is electrically connected to the first signal terminal of the control unit 10, the fourth terminal of the first optocoupler U1 is electrically connected to the first terminal of the first resistor R1, the second terminal of the first resistor R1 is electrically connected to the positive terminal of the energy storage converter 30, the gate of the first MOSFET Q1 is electrically connected to the first converter control terminal of the control unit 10, and the second electrode of the first MOSFET Q1 is grounded. The second control circuit 50 includes a second optocoupler U2, a second MOSFET Q2, a second resistor R2, and a third resistor R3. The first terminal of the second optocoupler U2... The second optocoupler U2 is electrically connected to the power supply. The second terminal of the second optocoupler U2 is electrically connected to the first terminal of the second MOSFET Q2. The third terminal of the second optocoupler U2 is electrically connected to the positive terminal of the battery module 20 through the second resistor R2. The fourth terminal of the second optocoupler U2 is electrically connected to the first signal terminal of the control unit 10. The fourth terminal of the second optocoupler U2 is electrically connected to the first terminal of the third resistor R3. The second terminal of the third resistor R3 is electrically connected to the reference voltage terminal of the control unit 10. The gate of the second MOSFET Q2 is electrically connected to the first battery module control terminal of the control unit 10. The second terminal of the second MOSFET Q2 is grounded. The control unit 10 is used to determine the voltage of the battery module 20 and perform insulation detection and adhesion detection on the battery module 20 through the first control circuit 40 and the second control circuit 50.

[0027] Specifically, such as Figure 1As shown, the first signal terminal of the control unit 10 acquires the first voltage divider signal CH1, the first converter control terminal of the control unit 10 outputs the first converter control signal PACK+_CTL, the first battery module control terminal of the control unit 10 outputs the first battery module control signal BAT+_CTL, the reference voltage terminal of the control unit 10 outputs the reference voltage VREF, the positive terminal of the energy storage converter 30 outputs the positive voltage PACK+, the positive terminal of the battery module 20 outputs the positive voltage BAT+, the battery module 20 can supply power to the load, and the power supply can output voltage VCC. When the output signal PACK+_CTL from the first converter control terminal of the control unit 10 is high, the first MOSFET Q1 is turned on, the light-emitting side of the first optocoupler U1 is activated, and the photosensitive side of the first optocoupler U1 is turned on. The voltage of PACK+ at the positive terminal of the energy storage converter 30 is transmitted to the first signal terminal of the control unit 10 through the voltage divider resistor, i.e., the first resistor R1. When the output signal PACK+_CTL from the first converter control terminal of the control unit 10 is low, the first MOSFET Q1 is turned off, and the voltage PACK+ at the positive terminal of the energy storage converter 30 cannot be transmitted to the first signal terminal of the control unit 10. When the output signal BAT+_CTL from the first battery module control terminal of the control unit 10 is high, the second MOSFET Q2 is turned on, the light-emitting side of the second optocoupler U2 is activated, and the photosensitive side of the second optocoupler U2 is turned on. The voltage BAT+ at the positive terminal of the battery module 20 is transmitted to the first signal terminal of the control unit 10 through the voltage divider resistor, i.e., the second resistor R2. When the output signal BAT+_CTL from the first battery module control terminal of the control unit 10 is low, the first MOSFET Q1 is turned off, and the voltage BAT+ at the positive terminal of the battery module 20 cannot be transmitted to the first signal terminal of the control unit 10.

[0028] Furthermore, when the control unit 10 controls the first optocoupler U1 and the second optocoupler U2 to conduct and there is no output at the reference voltage terminal, the voltage of the battery module 20 can be determined through the first resistor R1 and the second resistor R2. The insulation resistance between the positive terminal of the battery module 20 and ground is set to R. X The insulation resistance between the negative terminal and ground is R. Y When the control unit 10 controls the first optocoupler U1 to be turned on, the second optocoupler U2 to be turned off, and the reference voltage terminal of the control unit 10 has no output, Among them, V BAT The voltage of battery module 20, V AIN0 The voltage V collected by one analog channel AIN0 of control unit 10 AIN1 The voltage acquired by another analog channel AIN1 of the control unit 10, and the insulation resistance of the positive terminal of the battery module 20 to ground. Among them, V AIN2 The voltage V collected by one analog channel AIN2 of control unit 10 AIN3The voltage acquired by another analog channel AIN3 of the control unit 10, and the insulation resistance of the negative terminal of the battery module 20 to ground. When the control unit 10 controls the first optocoupler U1 to be turned on, the second optocoupler U2 to be turned off, and the reference voltage terminal VREF of the control unit 10 has no output, the voltage values ​​of the analog channels AIN0-AIN1 of the control unit 10 are: The value of VREF can be 2.048V. If the contactor between the positive terminal of the battery module 20 and the positive terminal of the energy storage converter 30 is stuck, the above expression has a calculated value; if there is no sticking, there is no calculated value.

[0029] The isolation detection circuit provided in this embodiment includes a control unit, a battery module, an energy storage converter, a first control circuit, and a second control circuit. The first control circuit includes a first optocoupler, a first MOSFET, and a first resistor. The second control circuit includes a second optocoupler, a second MOSFET, a second resistor, and a third resistor. The control unit is used to determine the voltage of the battery module and perform insulation and adhesion detection on the battery module through the first and second control circuits. The isolation detection circuit provided in this embodiment can control the connection state between the battery module and the control unit through the first control circuit and the connection state between the energy storage converter and the control unit through the second control circuit, realizing time-sharing control of the battery module and the energy storage converter. Based on isolating the control unit from the battery module and the energy storage converter, it achieves voltage acquisition, insulation detection, and adhesion detection.

[0030] Optionally, the above-mentioned isolation detection circuit further includes a third control circuit 60. The third control circuit 60 includes a third optocoupler U3, a third MOSFET Q3, and a fourth resistor R4. The first terminal of the third optocoupler U3 is electrically connected to the power supply, the second terminal of the third optocoupler U3 is electrically connected to the first electrode of the third MOSFET Q3, the third terminal of the third optocoupler U3 is electrically connected to the second signal terminal of the control unit 10, the fourth terminal of the third optocoupler U3 is electrically connected to the first terminal of the fourth resistor R4, the second terminal of the fourth resistor R4 is electrically connected to the negative terminal of the energy storage converter 30, the gate of the third MOSFET Q3 is electrically connected to the second converter control terminal of the control unit 10, and the second electrode of the third MOSFET Q3 is grounded.

[0031] For details, please refer to Figure 1The second signal terminal of control unit 10 acquires the second voltage divider signal CH2, and the second converter control terminal of control unit 10 outputs the second converter control signal PACK-_CTL. The negative terminal of energy storage converter 30 outputs a negative voltage PACK-. When the output signal of the second converter control terminal of control unit 10 is high, the third MOSFET Q3 is turned on, the light-emitting side of the third optocoupler U3 is activated, and the photosensitive side of the third optocoupler U3 is turned on. The voltage at the negative terminal of energy storage converter 30 is transmitted to the second signal terminal of control unit 10 through the voltage divider resistor, i.e., the fourth resistor R4. When the output signal of the second converter control terminal of control unit 10 is low, the third MOSFET Q3 is turned off, and the voltage at the negative terminal of energy storage converter 30 cannot be transmitted to the second signal terminal of control unit 10. Control unit 10 can control the circuit operation state of the negative terminal of energy storage converter 30 by controlling the output signal of the second converter control terminal.

[0032] Optionally, the above-mentioned isolation detection circuit further includes a first diode D1 and a second diode D2. The second end of the first resistor R1 is electrically connected to the negative terminal of the energy storage converter 30 through the first diode D1, and the second end of the fourth resistor R4 is electrically connected to the positive terminal of the energy storage converter 30 through the second diode D2. Specifically, the anode of the first diode D1 is electrically connected to the positive terminal of the energy storage converter 30, the cathode of the first diode D1 is electrically connected to the second end of the first resistor R1, the anode of the second diode D2 is electrically connected to the negative terminal of the energy storage converter 30, and the cathode of the second diode D2 is electrically connected to the second end of the fourth resistor R4.

[0033] The diode has unidirectional conductivity. The first diode D1 can prevent the voltage transmitted from the positive terminal of the energy storage converter 30 to the first signal terminal of the control unit 10 from being transmitted in reverse to the positive terminal PACK+ of the energy storage converter 30. Similarly, the second diode D2 can prevent the voltage transmitted from the negative terminal of the energy storage converter 30 to the second signal terminal of the control unit 10 from being transmitted in reverse to the negative terminal of the energy storage converter 30.

[0034] Optionally, the second control circuit 50 further includes a fourth optocoupler U4, a fourth MOSFET Q4, a fifth resistor R5, and a sixth resistor R6. The first terminal of the fourth optocoupler U4 is electrically connected to the power supply, the second terminal of the fourth optocoupler U4 is electrically connected to the first electrode of the fourth MOSFET Q4, the third terminal of the fourth optocoupler U4 is electrically connected to the negative electrode of the battery module 20 through the fifth resistor R5, the fourth terminal of the fourth optocoupler U4 is electrically connected to the second signal terminal of the control unit 10, the fourth terminal of the fourth optocoupler U4 is electrically connected to the second terminal of the third resistor R3 through the sixth resistor R6, the gate of the fourth MOSFET Q4 is electrically connected to the second battery module control terminal of the control unit 10, and the second electrode of the fourth MOSFET Q4 is grounded.

[0035] Specifically, the second battery module control terminal of control unit 10 outputs the second battery module control signal BAT-_CTL, and the negative terminal of battery module 20 outputs a negative voltage BAT-. When control unit 10 controls the second optocoupler U2 and the fourth optocoupler U4 to be turned on, and the first optocoupler U1, the third optocoupler U3, and the fifth optocoupler U5 to be turned off, and the reference voltage terminal of control unit 10 has no output, the voltage values ​​of the analog channels AIN3-AIN2 of control unit 10 are: The voltage values ​​of analog channels AIN0-AIN1 are: The total voltage of the battery module 20 can be calculated from either of the two voltage equations above. When the control unit 10 controls the first optocoupler U1 and the third optocoupler U3 to be turned on, and the second optocoupler U2, the fourth optocoupler U4, and the fifth optocoupler U5 to be turned off and there is no output at the reference voltage terminal, the total voltage V of the energy storage converter 30 can be collected. PACK The voltage values ​​for analog channels AIN3-AIN2 are as follows: The voltage values ​​of analog channels AIN0-AIN1 are: The total voltage of the energy storage converter 30 can be calculated from either of the two voltage equations above, thereby realizing the voltage acquisition of the battery module 20 and the energy storage converter 30.

[0036] Furthermore, when the control unit 10 controls both the first optocoupler U1 and the fifth optocoupler U5 to be turned on, and the second optocoupler U2, the third optocoupler U3, and the fourth optocoupler U4 are all turned off and there is no output at the reference voltage terminal, When the control unit 10 controls the fourth optocoupler U4 and the fifth optocoupler U5 to be turned on, and the first optocoupler U1, the second optocoupler U2, and the third optocoupler U3 are all turned off and there is no output at the reference voltage terminal. Where R5 = R2 and R6 = R3, combining the above two equations, we can obtain the insulation resistance of the positive terminal of battery module 20 to ground. And the insulation resistance of the negative terminal of battery module 20 to ground This enables insulation detection of battery module 20.

[0037] Optionally, the second control circuit also includes a fifth optocoupler U5 and a fifth MOSFET Q5. The first terminal of the fifth optocoupler U5 is electrically connected to the power supply, the second terminal of the fifth optocoupler U5 is electrically connected to the first electrode of the fifth MOSFET Q5, the third terminal of the fifth optocoupler U5 is grounded, the fourth terminal of the fifth optocoupler U5 is electrically connected to the second terminal of the third resistor, the gate of the fifth MOSFET Q5 is electrically connected to the ground control terminal of the control unit 10, and the second electrode of the fifth MOSFET Q5 is grounded.

[0038] For details, please refer to Figure 1The control unit 10 can output a ground control signal EARTH_CTL through the ground control terminal and transmit the ground control signal to the fifth MOSFET Q5. Additionally, the second control circuit includes a seventh resistor R7 and a first inductor LV1. The second terminal of the fifth optocoupler U5 is electrically connected to the first terminal of the fifth MOSFET Q5 through the seventh resistor R7, and the third terminal of the fifth optocoupler U5 is grounded through the first inductor LV1. For example, as... Figure 1 As shown, the second control circuit also includes resistors R8 and R9, the first control circuit also includes resistor R10, and the third control circuit also includes resistor R11.

[0039] Figure 2 This is a schematic diagram of a partial structure of an isolation detection circuit provided in an embodiment of the present invention, for reference. Figure 2 Optionally, the above-mentioned isolation detection circuit also includes a first contactor RLY1 and a second contactor RLY2. The positive terminal of the battery module 20 is electrically connected to the positive terminal of the energy storage converter 30 through the first contactor RLY1, and the negative terminal of the battery module 20 is electrically connected to the negative terminal of the energy storage converter 30 through the second contactor RLY2. The control unit 10 is specifically used to detect whether the first contactor RLY1 is stuck and whether the second contactor RLY2 is stuck.

[0040] The power conversion system (PCS) 30 provides power to the battery module 20. When the battery module 20's charge is too low, the control unit 10 can close both the first contactor RLY1 and the second contactor RLY2, thereby supplying power to the battery module 20 through the PCS, i.e., the power conversion system 30. When the control unit 10 controls the first optocoupler U1 and the fourth optocoupler U4 to be turned on, and the second optocoupler U2, the third optocoupler U3, and the fifth optocoupler U5 to be turned off, and the reference voltage terminal of the control unit 10 outputs normally, the voltage values ​​of the analog channels AIN0-AIN1 are: If the first contactor RLY1 is stuck, the above expression has a calculated value; if it is not stuck, there is no calculated value. When the control unit 10 controls the second optocoupler U2 and the third optocoupler U3 to be turned on, and the first optocoupler U1, the fourth optocoupler U4 and the fifth optocoupler U5 to be turned off and the reference voltage terminal outputs normally, the voltage value of the analog channel AIN0-AIN1 is: If the second contactor RLY2 is stuck, the above expression has a calculated value; if it is not stuck, there is no calculated value, thus realizing adhesion detection.

[0041] Figure 3 This is a schematic diagram of a partial structure of another isolation detection circuit provided in an embodiment of the present invention, for reference. Figure 3 Optionally, the above-mentioned isolation detection circuit also includes a power isolation element U6, and the power control interface of the control unit 10 is electrically connected to the power isolation element U6.

[0042] Specifically, the power control interface of control unit 10 can output a power control signal POWER_EN. The power supply adopts a DC / DC isolated power supply, namely the power isolation element U6, which can output two voltages, VDD_ISO (GND_ISO ground signal) and VCC (GND ground signal), to supply the two ends of the isolation side of the circuit to achieve electrical isolation. The power control signal POWER_EN output by control unit 10 can realize the start and stop control of the entire circuit. When the power control signal POWER_EN is high, the power isolation element U6 works normally and the isolation detection circuit is powered on; when the power control signal POWER_EN is low, the power isolation element U6 stops operating (voltage VCC can be output normally), and the isolation detection circuit is de-energized, thereby realizing the start and stop control of the circuit. When a fault occurs or the circuit needs to be stopped, it can be stopped in real time, ensuring the safety of the circuit.

[0043] Figure 4 This is a schematic diagram of a partial structure of another isolation detection circuit provided in an embodiment of the present invention, for reference. Figure 4 Optionally, the control unit 10 includes a controller 11 and a signal acquisition element U7. The controller 11 is electrically connected to the signal acquisition element U7. The first voltage output terminal of the power isolation element U6 is electrically connected to the first voltage input terminal of the signal acquisition element U7. The second voltage output terminal of the power isolation element U6 is electrically connected to the second voltage input terminal of the signal acquisition element U7. The signal acquisition element is used to acquire voltage signals and convert the voltage signals into communication signals.

[0044] In this design, controller 11 can be an MCU, and its power control interface serves as the power control interface for control unit 10. The first signal terminal, second signal terminal, and reference voltage terminal of signal acquisition element U7 serve as the first signal terminal, second signal terminal, and reference voltage terminal of control unit 10, respectively. The first inverter control terminal, second inverter control terminal, first battery module control terminal, and second battery module control terminal of controller 11 serve as the first inverter control terminal, second inverter control terminal, first battery module control terminal, and second battery module control terminal of control unit 10, respectively. The first voltage output terminal of power isolation element U6 outputs voltage VDD_ISO, which is the same as the first voltage input terminal of signal acquisition element U7. The second voltage output terminal of power isolation element U6 outputs ground signal GND_ISO, which is the same as the second voltage input terminal of signal acquisition element U7. Signal acquisition element U7 can acquire and convert signals, such as converting the acquired voltage signal into an SPI signal. (Reference) Figure 1 , 3 and Figure 4The voltage VCC can continuously supply power to each control circuit and control unit 10. The voltage VDD_ISO output by the power isolation element U6 can supply power to the signal acquisition element U7 and realize electrical isolation between the power supply and other devices in the circuit.

[0045] Optionally, the control unit 10 also includes a communication isolation element U8. The controller 11 and the signal acquisition element U7 are electrically connected through the communication isolation element U8. The communication isolation element U8 is used to convert the output voltage signal of the signal acquisition element U7 into a communication signal and transmit the communication signal to the controller 11. It is also used to transmit the control signal of the controller 11 to the signal acquisition element U7.

[0046] For details, please refer to Figure 4 The signal acquisition element U7 can be an ADC conversion chip such as ADS1147IPW, and the communication isolation element U8 can be an isolation chip such as Si8641ED. The communication isolation element U8 can realize signal isolation and communication, and achieve electrical isolation, isolating the battery module 20 and energy storage converter 30 from the controller 11. Since the output voltage of the battery module 20 is relatively high, such as several kilovolts, while the voltage of the controller 11 is relatively low, such as several volts, isolation can prevent signal interference and ensure signal reliability and anti-interference.

[0047] The isolation detection circuit provided in this embodiment allows the control unit to control the positive and negative terminals of the battery module, the ground terminal, and the positive and negative terminals of the PCS device to access the circuit in a time-division manner through various control circuits. This enables the acquisition, conversion, and communication of voltages from each channel, as well as voltage acquisition, insulation detection, and adhesion detection. Furthermore, the isolation detection circuit in this embodiment is modular, with a complete overall circuit function design, high timeliness, low cost, and is easy to mass-produce. By using power isolation components and signal acquisition components, electrical and signal isolation of the entire circuit can be achieved, protecting the safety of internal and external circuits and ensuring circuit reliability and anti-interference. The signal acquisition components have multiple analog signal acquisition channels and an SPI communication port. The analog signal acquisition channels are paired and differentially calculated to acquire voltage signals. After conversion by an internal ADC, the data information is transmitted to the controller via the SPI communication port, ensuring the accuracy of voltage acquisition and data integrity.

[0048] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. An isolated detection circuit, characterized by, The application relates to a battery module control device. The first control circuit comprises a first optocoupler, a first MOS tube and a first resistor, the first end of the first optocoupler is electrically connected with a power supply, the second end of the first optocoupler is electrically connected with the first pole of the first MOS tube, the third end of the first optocoupler is electrically connected with the first signal end of the control unit, the fourth end of the first optocoupler is electrically connected with the first end of the first resistor, the second end of the first resistor is electrically connected with the positive end of the energy storage converter, the gate of the first MOS tube is electrically connected with the first converter control end of the control unit, and the second pole of the first MOS tube is grounded. The second control circuit comprises a second optocoupler, a second MOS tube, a second resistor and a third resistor, the first end of the second optocoupler is electrically connected with the power supply, the second end of the second optocoupler is electrically connected with the first pole of the second MOS tube, the third end of the second optocoupler is electrically connected with the positive pole of the battery module through the second resistor, the fourth end of the second optocoupler is electrically connected with the first signal end of the control unit, the fourth end of the second optocoupler is electrically connected with the first end of the third resistor, the second end of the third resistor is electrically connected with the reference voltage end of the control unit, the gate of the second MOS tube is electrically connected with the first battery module control end of the control unit, and the second pole of the second MOS tube is grounded. The control unit is used for determining the voltage of the battery module and performing insulation detection and adhesion detection on the battery module through the first control circuit and the second control circuit. The third control circuit comprises a third optocoupler, a third MOS tube and a fourth resistor, the first end of the third optocoupler is electrically connected with the power supply, the second end of the third optocoupler is electrically connected with the first pole of the third MOS tube, the third end of the third optocoupler is electrically connected with the second signal end of the control unit, the fourth end of the third optocoupler is electrically connected with the first end of the fourth resistor, the second end of the fourth resistor is electrically connected with the negative end of the energy storage converter, the gate of the third MOS tube is electrically connected with the second converter control end of the control unit, and the second pole of the third MOS tube is grounded.

2. The isolated detection circuit of claim 1, wherein, The first resistor is electrically connected with the positive end of the energy storage converter through the first diode, and the fourth resistor is electrically connected with the negative end of the energy storage converter through the second diode, wherein the positive pole of the first diode is electrically connected with the positive end of the energy storage converter, the negative pole of the first diode is electrically connected with the second end of the first resistor, the negative pole of the second diode is electrically connected with the negative end of the energy storage converter, and the positive pole of the second diode is electrically connected with the second end of the fourth resistor.

3. The isolation detection circuit of claim 2, wherein, ​ 4. The isolated detection circuit of claim 1, wherein, The second control circuit further comprises a fourth optocoupler, a fourth MOS tube, a fifth resistor and a sixth resistor, a first end of the fourth optocoupler is electrically connected with the power supply, a second end of the fourth optocoupler is electrically connected with a first pole of the fourth MOS tube, a third end of the fourth optocoupler is electrically connected with a negative pole of the battery module through the fifth resistor, a fourth end of the fourth optocoupler is electrically connected with a second signal end of the control unit, the fourth end of the fourth optocoupler is electrically connected with a second end of the third resistor through the sixth resistor, a gate of the fourth MOS tube is electrically connected with a second battery module control end of the control unit, and a second pole of the fourth MOS tube is grounded.

5. The isolated detection circuit of claim 1, wherein, The second control circuit further comprises a fifth optocoupler and a fifth MOS tube, a first end of the fifth optocoupler is electrically connected with the power supply, a second end of the fifth optocoupler is electrically connected with a first pole of the fifth MOS tube, a third end of the fifth optocoupler is grounded, a fourth end of the fifth optocoupler is electrically connected with a second end of the third resistor, a gate of the fifth MOS tube is electrically connected with a ground control end of the control unit, and a second pole of the fifth MOS tube is grounded.

6. The isolated detection circuit of claim 5, wherein, The second control circuit further comprises a seventh resistor and a first inductor, the second end of the fifth optocoupler is electrically connected with the first pole of the fifth MOS tube through the seventh resistor, and the third end of the fifth optocoupler is grounded through the first inductor.

7. The isolated detection circuit of claim 1, wherein, The battery module further comprises a first contactor and a second contactor, a positive pole of the battery module is electrically connected with a positive end of the energy storage converter through the first contactor, and a negative pole of the battery module is electrically connected with a negative end of the energy storage converter through the second contactor; and the control unit is specifically used for detecting whether the first contactor is stuck and whether the second contactor is stuck.

8. The isolated detection circuit of claim 1, wherein, The battery module further comprises a power supply isolation element, and a power supply control interface of the control unit is electrically connected with the power supply isolation element.

9. The isolated detection circuit of claim 8, wherein, The control unit comprises a controller and a signal acquisition element, the controller is electrically connected with the signal acquisition element, a first voltage output end of the power supply isolation element is electrically connected with a first voltage input end of the signal acquisition element, a second voltage output end of the power supply isolation element is electrically connected with a second voltage input end of the signal acquisition element, and the signal acquisition element is used for acquiring a voltage signal and converting the voltage signal into a communication signal. The power supply control interface of the controller is used as the power supply control interface of the control unit, the first signal end, the second signal end and the reference voltage end of the signal acquisition element are used as the first signal end, the second signal end and the reference voltage end of the control unit respectively, and the first converter control end, the second converter control end, the first battery module control end and the second battery module control end of the controller are used as the first converter control end, the second converter control end, the first battery module control end and the second battery module control end of the control unit respectively.

10. The isolated detection circuit of claim 9, wherein, The control unit further comprises a communication isolation element, the controller and the signal acquisition element are electrically connected through the communication isolation element, and the communication isolation element is used for transmitting the communication signal to the controller and transmitting the control signal of the controller to the signal acquisition element.

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