Insulation resistance detection circuit based on high-voltage energy storage system

Abstract

The utility model discloses an insulation resistance detection circuit based on a high-voltage energy storage system, which is characterized in that the input ends of a circuit signal acquisition circuit I and a circuit signal acquisition circuit II are connected with a singlechip circuit, and the circuit signal acquisition circuit I is connected with the input end I of a signal relay through a first sampling resistor group; the first output end of the signal relay is connected with the single-chip microcomputer circuit through the first operational amplifier combination circuit. The second signal acquisition circuit is connected with the second input end of the signal relay through a second sampling resistor group. The second output end of the signal relay is connected with the single-chip microcomputer circuit through a second operational amplifier combination circuit. One end of a coil of the signal relay is connected with a VCC power supply, and the other end of the coil is connected with the switching circuit to adjust the control voltage of the signal relay. The utility model discloses an insulation resistance detection circuit based on a high-voltage energy storage system, which improves the measurement accuracy of the system and reduces the interference on a measured circuit.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage systems, in particular to an insulation resistance detection circuit based on a high-voltage energy storage system. Background Art

[0002] The insulation resistance of a high-voltage energy storage system refers to the insulation impedance between the high-voltage electrical part of the high-voltage energy storage system and the accessible metal shell, which is the resistance value between the electrical part of the high-voltage system and the shell, representing the insulation performance of the components of the high-voltage system;

[0003] When high-voltage components are designed in production, they are all insulated from the shell. However, due to the complex use environment, there are factors such as high temperature, high humidity, low temperature, corrosion, and vibration, which cause the insulation performance of high-voltage components to decline or even fail, resulting in the shell being charged. In severe cases, a short circuit may occur between the high-voltage positive and negative poles, leading to system failures, personal injuries, and even safety accidents such as fires.

[0004] The currently commonly used circuit directly measures the high-voltage side voltage by the resistance voltage division method. Due to the errors of the voltage division resistors and the accuracy problems of the single-chip microcomputer ADC, etc., there are large errors in the measured values. Summary of the Utility Model

[0005] The utility model overcomes the deficiencies of the prior art and provides an insulation resistance detection circuit based on a high-voltage energy storage system. Through the operational amplifier voltage division and amplification circuit, the measurement accuracy of the system is improved, and the high impedance at the input end of the operational amplifier can introduce less influence on the measured circuit and has relatively high measurement accuracy.

[0006] To achieve the above object, the technical solution adopted by the utility model is: an insulation resistance detection circuit based on a high-voltage energy storage system, including:

[0007] A circuit signal acquisition circuit one and a circuit signal acquisition circuit two;

[0008] The input end of the circuit signal acquisition circuit one is connected to the I / O port of the single-chip microcomputer circuit. The output end of the circuit signal acquisition circuit one is connected to the input end one of the signal relay through the first sampling resistor group. The output end one of the signal relay is connected to the operational amplifier combination circuit one. The output end of the operational amplifier combination circuit one is the test circuit output end one and is connected to the I / O port of the single-chip microcomputer circuit;

[0009] The input end of the circuit signal acquisition circuit two is connected to the I / O port of the single-chip microcomputer circuit. The output end of the circuit signal acquisition circuit two is connected to the input end two of the signal relay through the second sampling resistor group. The output end two of the signal relay is connected to the operational amplifier combination circuit two. The output end of the operational amplifier combination circuit two is the test circuit output end two and is connected to the I / O port of the single-chip microcomputer circuit;

[0010] One end of the coil of the signal relay is connected to the VCC power supply of the power supply circuit, and the other end of the coil is connected to the switch circuit to adjust the control voltage of the signal relay.

[0011] In a preferred embodiment of the present invention, the circuit signal acquisition circuit one includes a resistor R1 connected to the HVB+EN terminal of the single-chip microcomputer circuit. The other end of the resistor R1 is connected to the solid-state relay one, and the solid-state relay one is of an opto-coupled type. The resistor R1 is connected to the diode on the opto-coupled side of the solid-state relay one, and the negative electrode of the diode on the opto-coupled side is grounded. The high-voltage sampling side of the solid-state relay one includes two groups of MOS transistors and diodes. One end of the high-voltage sampling side is connected to the input terminal one of the signal relay through the resistors R2 and R3 of the first sampling resistor group, and the other end of the high-voltage sampling side is connected to the positive terminal HVA+ wiring terminal of the external high-voltage input.

[0012] In a preferred embodiment of the present invention, the circuit signal acquisition circuit two includes a resistor R8 connected to the HVB-EN terminal of the single-chip microcomputer circuit. The other end of the resistor R8 is connected to the solid-state relay two, and the solid-state relay two is of an opto-coupled type. The resistor R8 is connected to the positive electrode of the diode on the opto-coupled side of the solid-state relay two, and the negative electrode of the diode on the electrically coupled side is grounded. The high-voltage sampling side of the solid-state relay two includes two groups of MOS transistors and diodes. One end of the high-voltage sampling side is connected to the input terminal two of the signal relay through the resistors R9, R10 and R11 of the second sampling resistor group, and the other end of the high-voltage sampling side is connected to the negative terminal HVA- wiring terminal of the external high-voltage input.

[0013] In a preferred embodiment of the present invention, the switch circuit includes a triode Q1. The collector of the triode Q1 is connected to the coil of the signal relay. The collector of the triode Q1 leads out two paths. One path is connected to the HV-EN wiring terminal of the single-chip microcomputer circuit through a resistor R6, and the other path is grounded at the common point with the emitter of the triode Q1 through a resistor R5.

[0014] In a preferred embodiment of the present invention, the operational amplifier combination circuit one includes an operational amplifier one. The positive input terminal of the power amplifier one is connected to the output terminal one of the signal relay. The negative input terminal of the operational amplifier one is connected to the output terminal of the power amplifier one. Two paths are led out from the power supply terminal of the operational amplifier one. One path is connected to the VCC power supply, and the other path is grounded through a capacitor C1. The grounding terminal of the operational amplifier one is directly grounded, and the output terminal of the power amplifier one is connected to the HVB+OUT terminal of the single-chip microcomputer circuit.

[0015] In a preferred embodiment of the present utility model, the operational amplifier combination circuit two includes an operational amplifier two. The negative input terminal of the power amplifier two is connected to the output terminal two of the signal relay, and the negative input terminal of the operational amplifier two is connected to the output terminal of the power amplifier two through a resistor R7. The positive input terminal of the operational amplifier two is grounded through a resistor R2, and the power supply terminal of the operational amplifier two is connected to the VCC power supply. The ground terminal of the operational amplifier one is connected to GND, and the output terminal of the power amplifier two is connected to the HVB-OUT terminal of the single-chip microcomputer circuit.

[0016] In a preferred embodiment of the present utility model, the positive input terminal of the operational amplifier combination circuit one is also grounded through an RC parallel circuit.

[0017] In a preferred embodiment of the present utility model, the negative input terminal of the operational amplifier combination circuit two is also grounded through a capacitor C3.

[0018] Specifically, the circuit under test is a high-voltage energy storage system; the two test points at both ends of the circuit under test are respectively the high-voltage side output terminal of the high-voltage electrical part in the high-voltage energy storage system and the metal shell that can be contacted in the high-voltage electrical part of the high-voltage energy storage system. What is detected is the insulation resistance between the high-voltage side output terminal of the high-voltage electrical part in the high-voltage energy storage system in the circuit under test and the metal shell that can be contacted in the high-voltage electrical part of the high-voltage energy storage system.

[0019] In a preferred embodiment of the present utility model, the power supply circuit includes a diode D6 connected to the +12V power supply. The negative pole of the diode D6 is connected in series with a resistor R30 and then leads out two paths. One path is grounded through a diode TVS1, and the other path is connected to a resistor R37 through a MOS tube Q16. A resistor R39 and a diode ZD9 are connected in parallel between the control terminal and the N pole of the MOS tube Q16. The control terminal of the MOS tube Q16 is grounded through a resistor R32 and a triode Q15, and the base of the triode Q15 is connected to the PON terminal of the single-chip microcomputer through a resistor R38. A resistor R39 is connected between the base and the emitter of the triode Q15. The output terminal of the resistor R37 is connected to the positive pole of a diode D13, the negative pole of the diode D13 is connected to the input terminal of a voltage regulator chip, a capacitor C13 is connected between the input terminal and the ground terminal of the voltage regulator chip. The output terminal of the voltage regulator chip leads out two paths. One path is connected to the ground terminal through a capacitor C14, and the other path is output through a resistor R111. The output terminal of the resistor R111 is connected to the ground terminal through a diode ESD1; and the output terminal of the resistor R37 is the VCC power supply, and the output terminal of the resistor R111 is the 3.3V power supply.

[0020] In a preferred embodiment of the present utility model, the single-chip microcomputer circuit includes a single-chip microcomputer, and a single-chip microcomputer driving circuit, an indicator light circuit, and a UART interface circuit connected to the single-chip microcomputer.

[0021] Compared with the prior art, the beneficial effects achieved by the present utility model are as follows:

[0022] An insulation resistance detection circuit based on a high-voltage energy storage system disclosed by the present utility model improves the measurement accuracy of the system and the high resistance at the input end of the operational amplifier through an operational amplifier voltage division and amplification circuit, which can introduce less influence on the measured circuit and has relatively high measurement accuracy.

[0023] The present utility model measures the resistance between the high-voltage side output end of the high-voltage energy storage system and the accessible metal shell by using an operational amplifier to detect the change of the insulation resistance of the high-voltage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present utility model will be further described below in conjunction with the drawings and embodiments.

[0025] Figure 1 It is a schematic diagram of the insulation resistance detection structure of the preferred embodiment in the present utility model;

[0026] Figure 2 It is the circuit schematic diagram of the preferred embodiment in the present utility model;

[0027] Figure 3 It is the equivalent circuit diagram when the switch S1 in the principle block diagram of the preferred embodiment in the present utility model is closed and the resistor R is connected in parallel across Rp;

[0028] Figure 4 It is the equivalent circuit diagram when the switch S2 in the principle block diagram of the preferred embodiment in the present utility model is closed and the resistor R is connected in parallel across Rn.

[0029] Figure 5 It is the equivalent circuit diagram when the switches S1 and S2 in the principle block diagram of the preferred embodiment in the present utility model are closed simultaneously, the resistor R is connected in parallel across Rn, and the resistor R is connected in parallel across Rp.

[0030] Figure 6 It is the VCC power supply circuit and the single-chip microcomputer circuit of the preferred embodiment in the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The technical solution of the present utility model will be described in detail below through the drawings and specific embodiments. It should be understood that the embodiments of the present utility model and the specific features in the embodiments are detailed descriptions of the technical solution of the present utility model, rather than limitations on the technical solution of the present utility model. Without conflict, the technical features in the embodiments of the present utility model and the embodiments can be combined with each other.

[0032] The term "and / or" is merely a description of the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, the character " / " generally indicates that the associated objects before and after are in an "or" relationship. Embodiment 1

[0033] An insulation resistance detection circuit based on a high-voltage energy storage system includes: a circuit signal acquisition circuit one and a circuit signal acquisition circuit two; the input end of the circuit signal acquisition circuit one is connected to one end of the circuit under test, the output end of the circuit signal acquisition circuit one is connected to the input end one of the signal relay through a first sampling resistor group, the output end one of the signal relay is connected to an operational amplifier combination circuit one, and the output end of the operational amplifier combination circuit one is the output end one of the test circuit; the input end of the circuit signal acquisition circuit two is connected to the other end of the circuit under test, the output end of the circuit signal acquisition circuit two is connected to the input end two of the signal relay through a second sampling resistor group, the output end two of the signal relay is connected to an operational amplifier combination circuit two, and the output end of the operational amplifier combination circuit two is the output end two of the test circuit; one end of the coil of the signal relay is connected to Figure 6 the VCC power supply in, the other end of the coil is connected to a switch circuit to adjust the control voltage of the signal relay. Specifically, the circuit under test is a high-voltage energy storage system; the two test points at both ends of the circuit under test are respectively the high-voltage side output end of the high-voltage electrical part in the high-voltage energy storage system and the metal shell that can be contacted in the high-voltage electrical part in the high-voltage energy storage system, and the insulation resistance between the high-voltage side output end of the high-voltage electrical part in the high-voltage energy storage system in the circuit under test and the metal shell that can be contacted in the high-voltage electrical part in the high-voltage energy storage system is detected.

[0034] Specifically, the first circuit signal acquisition circuit includes a resistor R1 connected to the HVB+EN terminal of the single-chip microcomputer circuit. The other end of the resistor R1 is connected to the first solid-state relay, and the first solid-state relay is of the opto-coupled type. The resistor R1 is connected to the diode on the opto-coupled side of the first solid-state relay, and the negative electrode of the diode on the opto-coupled side is grounded. The high-voltage sampling side of the first solid-state relay includes two groups of MOS transistors and diodes. One end of the high-voltage sampling side is connected to the first input terminal of the signal relay through the resistors R2 and R3 of the first sampling resistor group, and the other end of the high-voltage sampling side is connected to the positive terminal HVA+ terminal of the external high-voltage input. The second circuit signal acquisition circuit includes a resistor R8 connected to the HVB-EN terminal of the single-chip microcomputer circuit. The other end of the resistor R8 is connected to the second solid-state relay, and the second solid-state relay is of the opto-coupled type. The resistor R8 is connected to the positive electrode of the diode on the opto-coupled side of the second solid-state relay, and the negative electrode of the diode on the opto-coupled side is grounded. The high-voltage sampling side of the second solid-state relay includes two groups of MOS transistors and diodes. One end of the high-voltage sampling side is connected to the second input terminal of the signal relay through the resistors R9, R10, and R11 of the second sampling resistor group, and the other end of the high-voltage sampling side is connected to the negative terminal HVA- terminal of the external high-voltage input.

[0035] Specifically, the switch circuit includes a triode Q1. The collector of the triode Q1 is connected to the coil of the signal relay. Two paths are led out from the collector of the triode Q1. One path is connected to the HV-EN terminal through a resistor R6, and the other path is connected to the emitter of the triode Q1 and grounded together through a resistor R5.

[0036] Specifically, the first operational amplifier combination circuit includes an operational amplifier one. The positive input terminal of the power amplifier one is connected to the first output terminal of the signal relay. The negative input terminal of the operational amplifier one is connected to the output terminal of the power amplifier one. Two paths are led out from the power supply terminal of the operational amplifier one. One path is connected to the VCC power supply, and the other path is grounded through a capacitor C1. The grounding terminal of the operational amplifier one is directly grounded. The positive input terminal of the first operational amplifier combination circuit is also grounded through an RC parallel circuit. The second operational amplifier combination circuit includes an operational amplifier two. The negative input terminal of the power amplifier two is connected to the second output terminal of the signal relay. The negative input terminal of the operational amplifier two is connected to the output terminal of the power amplifier two through a resistor R7. The positive input terminal of the operational amplifier two is grounded through a resistor R2. The power supply terminal of the operational amplifier two is connected to the VCC power supply, and the grounding terminal of the operational amplifier one is connected to the GND. The negative input terminal of the second operational amplifier combination circuit is also grounded through a capacitor C3.

[0037] Furthermore, the models of both the solid-state relay one and the solid-state relay two are AQV258HAXC88 solid-state relays. The model of the signal relay is HFD4 / 5-SR. The models of the operational amplifier one and the operational amplifier two are MCP6L2T-E / SN. However, this is not limited to this. In other embodiments, products of other models can also be selected according to actual usage requirements, which will not be elaborated and listed one by one here. Embodiment 2

[0038] Based on Embodiment 1, the power supply circuit includes a diode D6 connected to the +12V power supply. The negative pole of the diode D6 is connected in series with a resistor R30 and then leads out two paths. One path is grounded through a diode TVS1, and the other path is connected to a resistor R37 through a MOS transistor Q16. A resistor R39 and a diode ZD9 are connected in parallel between the control terminal and the N pole of the MOS transistor Q16. The control terminal of the MOS transistor Q16 is grounded through a resistor R32 and a triode Q15, and the base of the triode Q15 is connected to the PON terminal of the single-chip microcomputer through a resistor R38. A resistor R39 is connected between the base and the emitter of the triode Q15. The output terminal of the resistor R37 is connected to the positive pole of a diode D13, and the negative pole of the diode D13 is connected to the input terminal of a voltage regulator chip. A capacitor C13 is connected between the input terminal and the ground terminal of the voltage regulator chip. The output terminal of the voltage regulator chip leads out two paths. One path is connected to the ground terminal through a capacitor C14, and the other path is output through a resistor R111. The output terminal of the resistor R111 is connected to the ground terminal through a diode ESD1; and the output terminal of the resistor R37 is the VCC power supply, and the output terminal of the resistor R111 is the 3.3V power supply. Embodiment 3

[0039] Based on Embodiment 1 or Embodiment 2, the single-chip microcomputer circuit includes a single-chip microcomputer, as well as a single-chip microcomputer driving circuit, an indicator light circuit, and a UART interface circuit connected to the single-chip microcomputer. Specifically, in this embodiment, the model of the single-chip microcomputer is GD32F103CBT6. The indicator light circuit uses light-emitting diodes connected to the RED interface and the GREEN interface of the single-chip microcomputer, and the other ends of the light-emitting diodes are grounded at a common point. The single-chip microcomputer driving circuit includes that the VBAT terminal of the single-chip microcomputer is grounded through a capacitor C19 and a capacitor C20 at a common point, and the connection node of the capacitor C19 and the capacitor C20 is connected to the 3.3V power supply at the output terminal of the resistor R111; the NRST terminal of the single-chip microcomputer is grounded through a capacitor C22 and connected to the 3.3V power supply at the output terminal of the resistor R111 through a resistor R41; the VSSA terminal and the VDDA terminal of the single-chip microcomputer are connected through a capacitor C23, and the VSSA terminal is grounded, and the VDDA terminal is connected to the 3.3V power supply at the output terminal of the resistor R111. The SW interface circuit is connected to the 3.3V power supply at the output terminal of the resistor R111. The UART interface circuit is connected to the TX terminal and the RX terminal of the single-chip microcomputer. Embodiment 4

[0040] Based on Example 1, Example 2, or Example 3, as Figures 1 - 5 shown; the principle analysis is as in Case 1 to Case 3.

[0041] Case 1

[0042] When HVB+_EN is set high and HVB-_EN is set low, the solid-state relays S1 are closed and S2 are open, which is equivalent to switch S1 in the principle block diagram being closed, and the resistor R is connected across Rp. The equivalent circuit diagram is as follows Figure 3 shown:

[0043] a. Denote the equivalent resistance of resistor R in parallel with Rp as Ra, and there is:

[0044] Resistor R = R2 + R3 + R4 = 2.01 MΩ;

[0045] ;

[0046] b. The microcontroller reads the voltage U1 across Rp. From the voltage follower of the operational amplifier and resistor voltage division, there is:

[0047] .

[0048] Case 2

[0049] When HVB+_EN is set low and HVB-_EN is set high, the solid-state relays S1 are open and S2 are closed, which is equivalent to switch S2 in the principle block diagram being closed, and the resistor R is connected across Rn. The equivalent circuit diagram is as Figure 4 shown:

[0050] a. Denote the equivalent resistance of resistor R in parallel with Rn as Rb, and there is:

[0051] Resistor R = R9 + R10 + R11 = 2.01 MΩ;

[0052] ;

[0053] b. The microcontroller reads the voltage U2 across Rn. From the voltage follower of the operational amplifier and resistor voltage division, there is:

[0054] .

[0055] Case 3

[0056] When HVB+_EN and HVB-_EN are both set high, the solid-state relays S1 and S2 are both closed, which is equivalent to switches S1 and S2 in the principle block diagram being closed simultaneously. The resistor R is connected across Rn, and the resistor R is connected across Rp. The equivalent circuit diagram is as Figure 5 shown:

[0057] a. Denote the equivalent resistance of the parallel connection of resistor R and Rp as Ra, and we have:

[0058] ;

[0059] b. Denote the equivalent resistance of the parallel connection of resistor R and Rn as Rb, and we have:

[0060] ;

[0061] c. The single-chip microcomputer reads the voltage U1' across Rp and the voltage U2' across Rn. According to the resistor voltage division, we have:

[0062] ;

[0063] And the total system voltage U = U1' + U2'.

[0064] From the above equations, by solving the binary linear equations, the values of Rn and Rp can be obtained as follows:

[0065] Rp = (U1' * U2 - U1 * U2') / (U1 * U2' + U2 * U2');

[0066] Rn = (U1' * U2 - U1 * U2') / (U1 * U2' + U1 * U1').

[0067] Working principle:

[0068] An insulation resistance detection circuit based on a high-voltage energy storage system disclosed by the present utility model improves the measurement accuracy of the system and the high resistance at the input end of the operational amplifier through an operational amplifier voltage division and amplification circuit, which can introduce less influence on the measured circuit and has relatively high measurement accuracy. The present utility model uses an operational amplifier to measure the resistance between the high-voltage side output end of the high-voltage energy storage system and the accessible metal shell, real-time detects the change of the insulation resistance of the high-voltage system, cuts off the high-voltage system in time when an abnormality is found, avoids the occurrence of accidents, and timely notifies the user of the fault status and conducts relevant processing.

[0069] (1) Select a bias resistor with high precision, small temperature offset, and appropriate resistance value in this embodiment. The detection accuracy is directly related to the ratio of the bias resistor to the resistor to be measured. When the bias resistor is much smaller than the insulation resistance, the detection error is the smallest. However, too low a bias resistor will cause a significant reduction in the insulation resistance of the high-voltage system, bringing an additional failure risk. Therefore, the size of the bias resistor is generally selected in the MΩ level.

[0070] (2) Improve the voltage detection accuracy. Improve it in terms of circuit by adding a filtering circuit and using a high-resolution AD circuit, etc. In addition, by reasonably designing the voltage division circuit, the larger the measured voltage value, the smaller the voltage error.

[0071] Enlightened by the ideal embodiments of the present utility model, through the above description, relevant personnel can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. An insulation resistance detection circuit based on a high-voltage energy storage system, characterized in that Comprising: Circuit signal acquisition circuit one and circuit signal acquisition circuit two; The input end of the circuit signal acquisition circuit one is connected to the I / O port of the single-chip microcomputer circuit. The output end of the circuit signal acquisition circuit one is connected to the input end one of the signal relay through the first sampling resistor group. The output end one of the signal relay is connected to the operational amplifier combination circuit one. The output end of the operational amplifier combination circuit one is the test circuit output end one and is connected to the I / O port of the single-chip microcomputer circuit; The input end of the circuit signal acquisition circuit two is connected to the I / O port of the single-chip microcomputer circuit. The output end of the circuit signal acquisition circuit two is connected to the input end two of the signal relay through the second sampling resistor group. The output end two of the signal relay is connected to the operational amplifier combination circuit two. The output end of the operational amplifier combination circuit two is the test circuit output end two and is connected to the I / O port of the single-chip microcomputer circuit; One end of the coil of the signal relay is connected to the VCC power supply of the power supply circuit, and the other end of the coil is connected to the switch circuit to adjust the control voltage of the signal relay.

2. The insulation resistance detection circuit based on a high-voltage energy storage system according to claim 1, characterized in that: The circuit signal acquisition circuit one includes a resistor R1 connected to the HVB+EN end of the single-chip microcomputer circuit. The other end of the resistor R1 is connected to the solid-state relay one. The solid-state relay one is of the opto-coupled type; and the resistor R1 is connected to the diode on the opto-coupled side of the solid-state relay one, and the negative electrode of the diode on the opto-coupled side is grounded. The high-voltage sampling side of the solid-state relay one includes two groups of MOS tubes and diodes, and one end of the high-voltage sampling side is connected to the input end one of the signal relay through the resistor R2 and resistor R3 of the first sampling resistor group, and the other end of the high-voltage sampling side is connected to the positive electrode HVA+ wiring terminal of the external high-voltage input.

3. The insulation resistance detection circuit based on a high-voltage energy storage system according to claim 2, wherein: The circuit signal acquisition circuit two includes a resistor R8 connected to the HVB-EN end of the single-chip microcomputer circuit. The other end of the resistor R8 is connected to the solid-state relay two. The solid-state relay two is of the opto-coupled type; and the resistor R8 is connected to the positive electrode of the diode on the opto-coupled side of the solid-state relay two, and the negative electrode of the diode on the electro-coupled side is grounded. The high-voltage sampling side of the solid-state relay two includes two groups of MOS tubes and diodes, and one end of the high-voltage sampling side is connected to the input end two of the signal relay through the resistor R9, resistor R10 and resistor R11 of the second sampling resistor group, and the other end of the high-voltage sampling side is connected to the negative electrode HVA- wiring terminal of the external high-voltage input.

4. The insulation resistance detection circuit based on a high-voltage energy storage system according to claim 3, characterized in that: The switch circuit includes a triode Q1. The collector of the triode Q1 is connected to the coil of the signal relay. The collector of the triode Q1 leads out two paths. One path is connected to the HV-EN wiring terminal of the single-chip microcomputer circuit through a resistor R6, and the other path is grounded at the common point with the emitter of the triode Q1 through a resistor R5.

5. The insulation resistance detection circuit based on a high-voltage energy storage system according to claim 4, wherein: The first operational amplifier combination circuit includes an operational amplifier one. The positive input terminal of the first power amplifier is connected to the first output terminal of the signal relay. The negative input terminal of the operational amplifier one is connected to the output terminal of the first power amplifier. Two paths are led out from the power supply terminal of the operational amplifier one. One path is connected to the VCC power supply, and the other path is grounded through a capacitor C1. The grounding terminal of the operational amplifier one is directly grounded. The output terminal of the first power amplifier is connected to the HVB+OUT terminal of the single-chip microcomputer circuit.

6. The insulation resistance detection circuit based on a high-voltage energy storage system according to claim 5, wherein: The second operational amplifier combination circuit includes an operational amplifier two. The negative input terminal of the second power amplifier is connected to the second output terminal of the signal relay. And the negative input terminal of the operational amplifier two is connected to the output terminal of the second power amplifier through a resistor R7. The positive input terminal of the operational amplifier two is grounded through a resistor R2. And the power supply terminal of the operational amplifier two is connected to the VCC power supply. The grounding terminal of the operational amplifier one is connected to the GND. The output terminal of the second power amplifier is connected to the HVB - OUT terminal of the single-chip microcomputer circuit.

7. The insulation resistance detection circuit based on a high-voltage energy storage system according to claim 6, characterized in that, The positive input terminal of the first operational amplifier combination circuit is also grounded through an RC parallel circuit.

8. The insulation resistance detection circuit based on a high-voltage energy storage system according to claim 7, characterized in that: The negative input terminal of the second operational amplifier combination circuit is also grounded through a capacitor C3.

9. The insulation resistance detection circuit based on a high-voltage energy storage system according to claim 1, characterized in that: The power supply circuit includes a diode D6 connected to the +12V power supply. The negative terminal of the diode D6 is connected in series with a resistor R30 and then two paths are led out. One path is grounded through a diode TVS1, and the other path is connected to a resistor R37 through a MOS transistor Q16. A resistor R39 and a diode ZD9 are connected in parallel between the control terminal and the N pole of the MOS transistor Q16. The control terminal of the MOS transistor Q16 is grounded through a resistor R32 and a triode Q15. And the base of the triode Q15 is connected to the PON terminal of the single-chip microcomputer through a resistor R38. A resistor R39 is connected between the base and the emitter of the triode Q15. The output terminal of the resistor R37 is connected to the positive terminal of a diode D13. The negative terminal of the diode D13 is connected to the input terminal of a voltage regulator chip. A capacitor C13 is connected between the input terminal and the grounding terminal of the voltage regulator chip. Two paths are led out from the output terminal of the voltage regulator chip. One path is connected to the grounding terminal through a capacitor C14, and the other path is output through a resistor R111. And the output terminal of the resistor R111 is connected to the grounding terminal through a diode ESD1. And the output terminal of the resistor R37 is the VCC power supply, and the output terminal of the resistor R111 is the 3.3V power supply.

10. A insulation resistance detection circuit based on a high-voltage energy storage system according to claim 9, characterized in that: The single-chip microcomputer circuit includes a single-chip microcomputer, and a single-chip microcomputer crystal oscillator circuit, an indicator light circuit, and a UART interface circuit connected to the single-chip microcomputer.

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