Multi-channel isolation high-voltage power supply

Abstract

The utility model relates to a multichannel isolation high-voltage power supply, and belongs to the technical field of circuit structures. The multi-channel isolation high-voltage power supply comprises at least two mutually isolated channels, and each channel sequentially comprises an input overvoltage current-limiting protection circuit, an AC / DC circuit, a DC / DC circuit, an output overvoltage current-limiting protection circuit and a high-voltage relay circuit and is further connected with a high-voltage output interface. The circuit also comprises a voltage output control circuit, a current sampling circuit and a voltage sampling circuit, and is connected with a microcontroller outside the channel through a communication isolation circuit, thereby achieving the mutual isolation of a high-voltage part and a low-voltage part in the channel. Therefore, the multi-channel isolation high-voltage power supply which is small in current, low in cost, high in integration level and particularly suitable for the high-voltage fault injection test of the BMS controller is provided.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit structures, in particular to the technical field of circuits for testing a BMS controller, and specifically refers to a multi-channel isolated high-voltage power supply. Background Art

[0002] With the development of the new energy market, the number of electric vehicles has increased rapidly. As one of the core technologies of electric vehicles, the reliability, rationality and cost control of the battery management system (BMS) are very important. Before the BMS controller is applied to the real vehicle, it will undergo a high-voltage fault injection test. The high-voltage fault injection test is divided into two parts: high-voltage power and fault injection. The high-voltage power part can be tested with a real power battery or a high-voltage power supply. Since the high-voltage power supply is safer, more convenient and simple to implement, it has become the mainstream test method.

[0003] During the high-voltage fault injection test of the BMS controller, a high-voltage power supply is required to charge the large load capacitor in the high-voltage circuit. The high-voltage power supply needs to provide sufficient current capability, but this high-voltage and high-current power supply is expensive.

[0004] Another type of high-voltage fault injection test removes the large load capacitor in the high-voltage circuit and uses a high-voltage power supply to directly simulate the capacitor charge and discharge curve. This test only requires a small current to meet the requirements. However, the test requires at least two isolated high-voltage power supplies, one to simulate the total voltage of the high-voltage power battery pack, and the other to simulate the charge and discharge voltage curve across the large load capacitor.

[0005] Therefore, how to provide a multi-channel isolated high-voltage power supply with at least two channels, low current, low cost and high integration becomes an urgent problem to be solved in the high-voltage fault injection test of the BMS controller. Utility Model Content

[0006] The purpose of the utility model is to overcome the shortcomings of the above-mentioned prior art and provide a multi-channel isolated high-voltage power supply including at least two channels, with small current, low cost, high integration, and particularly suitable for high-voltage fault injection testing of BMS controllers.

[0007] In order to achieve the above-mentioned purpose, a multi-channel isolated high-voltage power supply of the utility model has the following structure:

[0008] The multi-channel isolated high-voltage power supply includes at least two mutually isolated channels between the external AC power supply and the high-voltage output interface 16.

[0009] Each of the channels is sequentially connected to an input overvoltage current limiting protection circuit 6, an AC / DC circuit 7, a DC / DC circuit 8, an output overvoltage current limiting protection circuit 9 and a high-voltage relay circuit 10 starting from the voltage input end, and the output end of the high-voltage relay circuit 10 of each channel is connected to the high-voltage output interface 16;

[0010] Each of the channels further comprises a voltage output control circuit 12, a current sampling circuit 13 and a voltage sampling circuit 14 connected to the DC / DC circuit 8, the output ends of the current sampling circuit 13 and the voltage sampling circuit 14 are connected to the microcontroller 2 outside the channel through the communication isolation circuit 15 of the channel, and the microcontroller 2 is connected to the DC / DC circuit 8 of each channel through the communication isolation circuit 15 of each channel and the corresponding voltage output control circuit 12;

[0011] The communication isolation circuit 15 in each channel isolates the voltage output control circuit 12 , the voltage sampling circuit 14 and the current sampling circuit 13 of the channel from the external microcontroller 2 .

[0012] The multi-channel isolated high-voltage power supply further comprises a communication interface 1 , which is connected to the microcontroller 2 via a CAN bus.

[0013] In the multi-channel isolated high-voltage power supply, the microcontroller 2 is connected to the corresponding high-voltage relay circuit 10 through the communication isolation circuit 15 of each channel to control the connection or disconnection between the high-voltage relay circuit 10 and the high-voltage output interface 16.

[0014] In the multi-channel isolated high-voltage power supply, each of the channels further includes a voltage discharge resistor 11 connected to the high-voltage relay circuit 10. The voltage discharge resistor 11 is connected in series with the high-voltage relay in the high-voltage relay circuit 10 to quickly discharge the voltage.

[0015] The multi-channel isolated high-voltage power supply also includes a temperature detection circuit 3 and a fan control circuit 4 connected to the microcontroller 2. The temperature detection circuit 3 detects the temperature of each channel in real time and drives the fan control circuit 4 through the microcontroller 2.

[0016] The multi-channel isolated high-voltage power supply further includes an OLED display unit 5 connected to the microcontroller 2 , and the OLED display unit 5 receives and displays the high-voltage output status information of each channel from the microcontroller 2 .

[0017] In the multi-channel isolated high-voltage power supply, the input overvoltage current limiting protection circuit 6 includes: a fuse F1 connected to the live wire L of the external AC power supply, a varistor RV1 connected between the live wire L and the neutral wire N, a first safety capacitor CY1 connected between the live wire L and the ground wire PE, and a second safety capacitor CY2 connected between the neutral wire N and the ground wire PE, and also includes a common-mode filter L1. After the live wire L and the neutral wire N suppress common-mode noise through the common-mode filter L1, they are connected to the AC / DC circuit 7; the AC / DC circuit 7 is connected to the DC / DC circuit 8 through the electrolytic capacitor CE1.

[0018] The multi-channel isolated high-voltage power supply also includes a DAC output control circuit 17 and an ADC sampling circuit 18 connected between the DC / DC circuit 8 and the communication isolation circuit 15. The DAC output control circuit 17 replaces the voltage output control circuit 12, and the ADC sampling circuit 18 replaces the current sampling circuit 13 and the voltage sampling circuit 14.

[0019] In the multi-channel isolated high-voltage power supply, the ADC sampling circuit 18 is connected to the positive electrode HV+ of the voltage output channel of the high-voltage output interface 16 through the diode D1 and the first high-voltage relay SW1; the voltage discharge resistor R1 (11) is connected in series with the second high-voltage relay SW2, and is connected between the positive electrode HV+ and the negative electrode HV- of the voltage output channel.

[0020] In the multi-channel isolated high-voltage power supply, the high-voltage output of each channel can be continuously adjusted in the range of 0V to 1000V, and the current can be adjusted in the range of 0A to 30mA.

[0021] The multi-channel isolated high-voltage power supply adopting the utility model includes at least two mutually isolated channels, each channel includes an input overvoltage current limiting protection circuit, an AC / DC circuit, a DC / DC circuit, an output overvoltage current limiting protection circuit and a high-voltage relay circuit in sequence, and then connected to a high-voltage output interface; it also includes a voltage output control circuit, a current sampling circuit and a voltage sampling circuit, which are connected to a microcontroller outside the channel through a communication isolation circuit to achieve mutual isolation between the high-voltage part and the low-voltage part in the channel; thus, a multi-channel isolated high-voltage power supply with low current, low cost, high integration, and particularly suitable for high-voltage fault injection testing of BMS controllers is provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a functional module schematic diagram of a multi-channel isolated high-voltage power supply of the utility model;

[0023] Figure 2 The utility model is a schematic diagram of the circuit structure of a multi-channel isolated high-voltage power supply.

[0024] Reference numerals:

[0025] 1-communication interface, 2-microcontroller, 3-temperature detection circuit, 4-fan control circuit, 5-OLED display unit, 6-input overvoltage current limiting protection circuit, 7-AC / DC circuit, 8-DC / DC circuit, 9-output overvoltage current limiting protection circuit, 10-high-voltage relay circuit, 11-voltage discharge circuit, 12-voltage output control circuit, 13-current sampling circuit, 14-voltage sampling circuit, 15-communication isolation circuit, 16-high-voltage output interface, 17-DAC output control circuit, 18-ADC sampling circuit. DETAILED DESCRIPTION

[0026] In order to more clearly understand the technical content of the present invention, the following embodiments are given in detail.

[0027] See also Figure 1 , which is a schematic diagram of the functional modules of the multi-channel isolated high-voltage power supply of the present invention.

[0028] In one embodiment, the multi-channel isolated high-voltage power supply includes at least two mutually isolated channels between the external AC power supply and the high-voltage output interface 16, such as Figure 1 As shown in , it includes 4 channels, namely channel 1 to channel 4.

[0029] Each of the channels is sequentially connected to an input overvoltage current limiting protection circuit 6, an AC / DC circuit 7, a DC / DC circuit 8, an output overvoltage current limiting protection circuit 9 and a high-voltage relay circuit 10 starting from the voltage input end, and the output end of the high-voltage relay circuit 10 of each channel is connected to the high-voltage output interface 16.

[0030] Each of the channels further comprises a voltage output control circuit 12, a current sampling circuit 13 and a voltage sampling circuit 14 connected to the DC / DC circuit 8, the output ends of the current sampling circuit 13 and the voltage sampling circuit 14 are connected to the microcontroller 2 outside the channel through the communication isolation circuit 15 of the channel, and the microcontroller 2 is connected to the DC / DC circuit 8 of each channel through the communication isolation circuit 15 of each channel and the corresponding voltage output control circuit 12;

[0031] The communication isolation circuit 15 in each channel isolates the voltage output control circuit 12 , the voltage sampling circuit 14 and the current sampling circuit 13 of the channel from the external microcontroller 2 .

[0032] The continuously adjustable range of the high voltage output of each channel is from 0V to 1000V, and the adjustable range of the current is from 0A to 30mA.

[0033] In a more preferred embodiment, the multi-channel isolated high-voltage power supply further includes a communication interface 1, which is connected to the microcontroller 2 via a CAN bus. The microcontroller 2 is connected to the corresponding high-voltage relay circuit 10 via the communication isolation circuit 15 of each channel to control the connection or disconnection between the high-voltage relay circuit 10 and the high-voltage output interface 16. Each of the channels further includes a voltage discharge resistor 11 connected to the high-voltage relay circuit 10, which is connected in series with the high-voltage relay in the high-voltage relay circuit 10 to quickly discharge the voltage.

[0034] In another preferred embodiment, the multi-channel isolated high-voltage power supply further includes a temperature detection circuit 3, a fan control circuit 4 and an OLED display unit 5 connected to the microcontroller 2, wherein the temperature detection circuit 3 detects the temperature of each channel in real time and drives the fan control circuit 4 through the microcontroller 2. The OLED display unit 5 receives and displays information such as the high-voltage output status of each channel from the microcontroller 2.

[0035] In a further preferred embodiment, Figure 2 As shown, the input overvoltage current limiting protection circuit 6 includes: a fuse F1 connected to the live wire L of the external AC power supply, a varistor RV1 connected between the live wire L and the neutral wire N, a first safety capacitor CY1 connected between the live wire L and the ground wire PE, and a second safety capacitor CY2 connected between the neutral wire N and the ground wire PE, and also includes a common mode filter L1. After the live wire L and the neutral wire N suppress common mode noise through the common mode filter L1, they are connected to the AC / DC circuit 7; the AC / DC circuit 7 is connected to the DC / DC circuit 8 through the electrolytic capacitor CE1.

[0036] In a more preferred embodiment, the multi-channel isolated high-voltage power supply further includes a DAC output control circuit 17 and an ADC sampling circuit 18 connected between the DC / DC circuit 8 and the communication isolation circuit 15, wherein the DAC output control circuit 17 replaces the voltage output control circuit 12, and the ADC sampling circuit 18 replaces the current sampling circuit 13 and the voltage sampling circuit 14. Figure 2 As shown, the ADC sampling circuit 18 is connected to the positive electrode HV+ of the voltage output channel of the high-voltage output interface 16 through the diode D1 and the first high-voltage relay SW1; the voltage discharge resistor R1 (11) is connected in series with the second high-voltage relay SW2 and connected between the positive electrode HV+ and the negative electrode HV- of the voltage output channel.

[0037] In the practical application of the multi-channel isolated high-voltage power supply of the utility model, the live wire L of the external AC input power supply is limited by the fuse F1, the varistor RV1 is connected between the live wire L and the neutral wire N as overvoltage protection, the safety capacitors CY1 and CY2 are respectively connected between L-PE and N-PE as safety protection, PE is the ground wire, L and N are suppressed by the common-mode filter L1 after the common-mode noise is suppressed, and then connected to the AC / DC circuit 7, the AC / DC circuit 7 converts the AC voltage into a DC constant voltage, and supplies power to the DC / DC after filtering by the electrolytic capacitor CE1.

[0038] The output voltage is set by sending a CAN control command externally through the communication interface 1. After receiving the command, the microcontroller 2 controls the DAC output control circuit 17 to output an adjustable voltage through the communication isolation circuit 15, and makes the DC / DC circuit 8 output a voltage amplified by a certain proportion.

[0039] The output overvoltage and current limiting protection circuit 9 is connected to the DC / DC circuit 8 to prevent overvoltage and overcurrent, thereby avoiding damage to the device under test at the output end.

[0040] The ADC sampling circuit 18 can collect the voltage and channel current output by the DC / DC circuit 8, and transmit them to the microcontroller 2 through the communication isolation circuit 15. The microcontroller 2 determines whether there is overvoltage or overcurrent, and sends a protection control instruction. The microcontroller 2 sends the actual collected voltage and channel current information to the OLED display unit for display, and can also obtain the voltage and channel current status through the CAN information on the communication interface 1.

[0041] The communication isolation circuit 15 isolates the DAC output control circuit 17 and the ADC sampling circuit 18 from the microcontroller 2 .

[0042] The voltage channel output by the ADC sampling circuit 18 is connected to the diode D1 to prevent the current from flowing back from the external active device. The high-voltage relay SW1 is a normally open relay, which is controlled by the microcontroller 2 and is responsible for disconnecting and connecting the voltage output channel HV+ with the external device under test. The voltage discharge resistor R1 is connected in series with the high-voltage relay SW2, and is connected between the positive electrode HV+ and the negative electrode HV- of the voltage output channel. By turning SW2 on and off, the voltage between HV+ and HV- can be reduced faster.

[0043] The temperature detection circuit 3 monitors the hot spots of the voltage output of each channel in real time and sends the temperature information of each channel to the microcontroller 2. After calculation, the microcontroller 2 controls the speed-adjustable fan to run. The temperature is proportional to the air volume.

[0044] The OLED display unit 5 can display information such as the voltage setting value of each channel, the voltage sampling value, the current sampling value, the switching state of the high-voltage relay SW1 and the high-voltage relay SW2, and the temperature in real time.

[0045] The continuously adjustable range of high-voltage output of each channel of the multi-channel isolated high-voltage power supply of the utility model is 0-1000V, and the current range is 0-30mA.

[0046] The multi-channel isolated high-voltage power supply of the utility model has low cost, high integration, strong reliability, and convenient implementation, and is particularly suitable for high voltage and low current scenarios.

[0047] The multi-channel isolated high-voltage power supply adopting the utility model includes at least two mutually isolated channels, each channel includes an input overvoltage current limiting protection circuit, an AC / DC circuit, a DC / DC circuit, an output overvoltage current limiting protection circuit and a high-voltage relay circuit in sequence, and then connected to a high-voltage output interface; it also includes a voltage output control circuit, a current sampling circuit and a voltage sampling circuit, which are connected to a microcontroller outside the channel through a communication isolation circuit to achieve mutual isolation between the high-voltage part and the low-voltage part in the channel; thus, a multi-channel isolated high-voltage power supply with low current, low cost, high integration, and particularly suitable for high-voltage fault injection testing of BMS controllers is provided.

[0048] In this specification, the utility model has been described with reference to its specific embodiments. However, it is obvious that various modifications and changes can be made without departing from the spirit and scope of the utility model. Therefore, the description and drawings should be regarded as illustrative rather than restrictive.

Claims

1. A multi-channel isolated high-voltage power supply, characterized in that: At least two mutually isolated channels are included between the external AC power supply and the high voltage output interface (16), Each of the channels is sequentially connected to an input overvoltage current limiting protection circuit (6), an AC / DC circuit (7), a DC / DC circuit (8), an output overvoltage current limiting protection circuit (9) and a high-voltage relay circuit (10) starting from the voltage input end, and the output end of the high-voltage relay circuit (10) of each channel is connected to the high-voltage output interface (16); Each of the channels further comprises a voltage output control circuit (12), a current sampling circuit (13) and a voltage sampling circuit (14) connected to the DC / DC circuit (8); the output ends of the current sampling circuit (13) and the voltage sampling circuit (14) are connected to a microcontroller (2) outside the channel via a communication isolation circuit (15) of the channel; the microcontroller (2) is connected to the DC / DC circuit (8) of each channel via the communication isolation circuit (15) and the corresponding voltage output control circuit (12); The communication isolation circuit (15) in each channel isolates the voltage output control circuit (12), voltage sampling circuit (14) and current sampling circuit (13) of the channel from the external microcontroller (2).

2. The multi-channel isolated high-voltage power supply according to claim 1, characterized in that: It also comprises a communication interface (1), wherein the communication interface (1) is connected to the microcontroller (2) via a CAN bus.

3. The multi-channel isolated high-voltage power supply according to claim 2, characterized in that: The microcontroller (2) is connected to the corresponding high-voltage relay circuit (10) via the communication isolation circuit (15) of each channel, and controls the connection or disconnection between the high-voltage relay circuit (10) and the high-voltage output interface (16).

4. The multi-channel isolated high-voltage power supply according to claim 3, characterized in that: Each of the channels further comprises a voltage discharge resistor (11) connected to the high-voltage relay circuit (10); the voltage discharge resistor (11) is connected in series with the high-voltage relay in the high-voltage relay circuit (10) for rapidly discharging voltage.

5. The multi-channel isolated high-voltage power supply according to claim 2, characterized in that: It also includes a temperature detection circuit (3) and a fan control circuit (4) connected to the microcontroller (2), wherein the temperature detection circuit (3) detects the temperature of each channel in real time and drives the fan control circuit (4) through the microcontroller (2).

6. The multi-channel isolated high-voltage power supply according to claim 2, characterized in that: It also includes an OLED display unit (5) connected to the microcontroller (2), and the OLED display unit (5) receives and displays the high-voltage output state information of each channel from the microcontroller (2).

7. The multi-channel isolated high-voltage power supply according to claim 1, characterized in that: The input overvoltage current limiting protection circuit (6) comprises: a fuse F1 connected to the live wire L of an external AC power source, a varistor RV1 connected between the live wire L and the neutral wire N, a first safety capacitor CY1 connected between the live wire L and the ground wire PE, and a second safety capacitor CY2 connected between the neutral wire N and the ground wire PE, and also comprises a common mode filter L1. After the live wire L and the neutral wire N pass through the common mode filter L1 to suppress common mode noise, they are connected to the AC / DC circuit (7); the AC / DC circuit (7) is connected to the DC / DC circuit (8) through the electrolytic capacitor CE1.

8. The multi-channel isolated high-voltage power supply according to claim 1, characterized in that: It also includes a DAC output control circuit (17) and an ADC sampling circuit (18) connected between the DC / DC circuit (8) and the communication isolation circuit (15), wherein the DAC output control circuit (17) replaces the voltage output control circuit (12), and the ADC sampling circuit (18) replaces the current sampling circuit (13) and the voltage sampling circuit (14).

9. The multi-channel isolated high-voltage power supply according to claim 8, characterized in that: The ADC sampling circuit (18) is connected to the positive electrode HV+ of the voltage output channel of the high-voltage output interface (16) via a diode D1 and a first high-voltage relay SW1; the voltage discharge resistor R1 (11) is connected in series with the second high-voltage relay SW2 and connected between the positive electrode HV+ and the negative electrode HV- of the voltage output channel.

10. The multi-channel isolated high-voltage power supply according to claim 1, characterized in that: The continuously adjustable range of the high voltage output of each channel is from 0V to 1000V, and the adjustable range of the current is from 0A to 30mA.

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