Insulation resistance detection circuit, control method and storage medium of energy storage battery

Abstract

The present application discloses an insulation resistance detection circuit, control method and storage medium of an energy storage battery, which is connected between the battery and the inverter load, including: a battery, an inverter load, a relay, a first resistor, a second resistor, a third resistor, a fourth resistor, a first switch, a second switch, a third switch, and a battery management system BMS; the battery management system BMS controls the relay to open; controls the first switch, the second switch, and the third switch to open, and measures the battery voltage V BAT The first and second switches are controlled to be off, the third switch is controlled to be on, and the battery voltage V1 is measured. The first, second, and third switches are controlled to be off, the battery voltage V2 is measured, and the insulation resistance values ​​of the positive and negative electrodes of the battery are calculated based on the formula. This application can improve the efficiency of insulation resistance testing of energy storage batteries while avoiding the disadvantage of performing insulation testing simultaneously after the battery and inverter load are connected.

Description

Technical Field

[0001] The present application relates to the field of resistance detection technology, and in particular to an insulation resistance detection circuit, a control method, and a storage medium for an energy storage battery. Background Art

[0002] The widespread use of renewable energy has driven rapid growth in the battery and inverter industries. Inverters and batteries, used to store electrical energy, are hazardous industrial products and can present various risks, including leakage and short circuits. Leakage occurs when battery aging, high-voltage breakdown, or environmental factors lead to contact between the positive or negative electrode and the outer casing. A short circuit, also a type of leakage, occurs when both the positive and negative electrodes are connected to the outer casing simultaneously. To prevent this, insulation impedance testing must be performed before using batteries and inverters to ensure there is no contact between the outer casing and the internal positive and negative electrodes, thus preventing accidents.

[0003] Currently, all batteries and inverters on the market are equipped with the function of automatically detecting insulation impedance. However, there is no effect when the two are used separately. However, when the battery and inverter load are connected, insulation detection may be performed at the same time, resulting in errors in the insulation impedance detection results of the battery or inverter load, causing the battery or inverter load to falsely report insulation abnormalities, affecting the normal use of the battery and inverter load. Summary of the Invention

[0004] In response to the above problems, the purpose of this application is to provide an insulation resistance detection circuit, control method and storage medium for an energy storage battery, which can improve the insulation resistance detection efficiency of the energy storage battery, while avoiding the disadvantage of performing insulation detection simultaneously after the battery and the inverter load are connected, and further avoiding errors in the insulation resistance detection results of the battery or inverter load.

[0005] According to one aspect of the present application, an insulation resistance detection circuit for an energy storage battery is provided, connected between the battery and an inverter load, comprising:

[0006] Relay, connected between the positive terminal of the battery and the positive terminal of the inverter load;

[0007] A first resistor, having a first end connected between the relay and the positive electrode of the inverter load, a second end connected in series with a second resistor, a first switch, and a fourth resistor, and finally connected between the negative electrode of the battery and the negative electrode of the inverter load;

[0008] a third resistor, a first end of which is connected between the first resistor and the second resistor, a second end of which is connected in series with the second switch, and finally connected between the fourth resistor and the negative electrode of the inverter load;

[0009] a third switch, one end of which is connected to the first end of the third resistor and the other end of which is grounded;

[0010] The detection circuit further includes a battery management system BMS; a first terminal of the battery management system BMS is connected to the positive electrode of the battery, a second terminal is connected to the negative electrode of the battery; a third terminal thereof is connected to the relay, a fourth terminal thereof is connected between the first switch and the fourth resistor, a fifth terminal thereof is connected to the first switch, a sixth terminal thereof is connected to the second switch, and a seventh terminal thereof is connected to the third switch;

[0011] The battery management system BMS is set to:

[0012] Before starting the insulation resistance test of the energy storage battery, communicate with the inverter load, and after receiving the insulation test completion signal of the inverter load, start the insulation resistance test of the energy storage battery;

[0013] Control relay is turned on;

[0014] Control the first switch, the second switch, and the third switch to open and measure the battery voltage V BAT ;

[0015] Control the first switch and the second switch to be turned off, control the third switch to be turned on, and measure the battery voltage V1;

[0016] Control the first switch, the second switch, and the third switch to be turned off, and measure the battery voltage V2;

[0017] Calculate the insulation resistance between the positive and negative electrodes of the battery based on the following formula:

[0018]

[0019] Among them, Y ISO+ Indicates the insulation resistance value of the battery positive electrode, Y ISO- Indicates the insulation resistance value of the negative electrode of the battery, Y1 indicates the resistance value of the first resistor, Y2 indicates the resistance value of the second resistor, Y3 indicates the resistance value of the third resistor, and Y L represents the resistance value of the fourth resistor.

[0020] Preferably, in some embodiments of the present application, the first resistor, the second resistor, the third resistor, and the fourth resistor are all fixed resistors.

[0021] Preferably, in some embodiments of the present application, the battery management system BMS is further configured to:

[0022] The insulation resistance value of the battery is preset;

[0023] If the insulation resistance value calculated by the detection circuit does not meet the preset standard, a battery fault alarm will be issued, the indicator light will light up, and the battery will be unable to output voltage or current.

[0024] Preferably, in some embodiments of the present application, the insulation resistance detection is set to automatic detection at power-on. Before the battery is powered on, the battery management system BMS performs insulation resistance detection on the entire battery through a detection circuit.

[0025] Preferably, in some embodiments of the present application, it is necessary to wait for at least 10 ms before measuring the battery voltages V1 and V2.

[0026] Preferably, in some embodiments of the present application, a Hall sensor is further provided, connected between the negative electrode of the battery and the second terminal of the battery management system BMS; and also connected to the eighth terminal of the battery management system BMS.

[0027] According to another aspect of the present application, the present application further provides a method for controlling an insulation resistance detection circuit of an energy storage battery, comprising the detection circuit of any one of the above embodiments:

[0028] Before starting the insulation resistance test of the energy storage battery, the battery management system BMS communicates with the inverter load. After receiving the insulation test completion signal from the inverter load, it starts the insulation resistance test of the energy storage battery.

[0029] Control relay is turned on;

[0030] Control the first switch, the second switch, and the third switch to open and measure the battery voltage V BAT ;

[0031] Control the first switch and the second switch to be turned off, control the third switch to be turned on, and measure the battery voltage V1;

[0032] Control the first switch, the second switch, and the third switch to be turned off, and measure the battery voltage V2;

[0033] Calculate the insulation resistance between the positive and negative electrodes of the battery based on the following formula:

[0034]

[0035] Among them, Y ISO+ Indicates the insulation resistance value of the battery positive electrode, Y ISO- Indicates the insulation resistance value of the negative electrode of the battery, Y1 indicates the resistance value of the first resistor, Y2 indicates the resistance value of the second resistor, Y3 indicates the resistance value of the third resistor, and Y L represents the resistance value of the fourth resistor.

[0036] Preferably, in some embodiments of the present application, the battery management system BMS presets the insulation impedance value of the battery; if the insulation impedance value calculated by the detection circuit does not meet the preset standard, a battery fault alarm is issued, the indicator light lights up, and the battery cannot output voltage or current.

[0037] Preferably, in some embodiments of the present application, the insulation resistance detection is set to automatic detection at power-on. Before the battery is powered on, the battery management system BMS performs insulation resistance detection on the entire battery through a detection circuit.

[0038] According to another aspect of the present application, the present application further provides a computer-readable storage medium having computer instructions stored thereon. When the computer instructions are executed by a processor, the detection circuit control method of any one of the above embodiments can be implemented.

[0039] It should be understood that within the scope of this application, the above-mentioned technical features of this application and the technical features described in detail below (such as in the embodiments) can be combined with each other to form new or preferred technical solutions. Due to space limitations, they will not be listed here one by one.

[0040] Compared with the existing technology, this application has the following technical effects:

[0041] This application can realize automatic power-on detection through the insulation resistance detection circuit without manual operation, which not only ensures personal safety and prevents electric shock accidents, but also effectively prevents equipment leakage and eliminates electrical fire hazards through the insulation impedance detection circuit; by cooperating with the high-efficiency detection program software built into the battery management system BMS, a quick test is automatically completed each time the power is turned on, and an accurate judgment can be made on the battery insulation performance in real time, which significantly improves the detection efficiency while improving safety. By communicating with the inverter load, it avoids false insulation alarms from the battery or inverter load, resulting in abnormal use. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The above and other features and advantages of the present application will become more apparent by describing in detail example embodiments thereof with reference to the accompanying drawings.

[0043] Figure 1 A schematic diagram of an insulation resistance detection circuit for an energy storage battery according to an embodiment of the present application is shown.

[0044] Reference numerals: 1 battery; 2 first resistor; 3 second resistor; 4 third resistor; 5 fourth resistor; 6 battery management system BMS; 7 first switch; 8 second switch; 9 third switch; 10 inverter load; 11 Hall sensor; 12 relay. DETAILED DESCRIPTION

[0045] To make the purpose, technical solutions, beneficial effects, and significant improvements of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the embodiments of this application. Obviously, all the embodiments described are only some of the embodiments of this application, not all of them; based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] The present application will be further described below in conjunction with specific implementations. It should be understood that these embodiments are only used to illustrate the present application and are not intended to limit the scope of the present application.

[0047] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment herein. The appearance of such phrases in various places in the specification does not necessarily refer to the same embodiment, nor does it limit mutually exclusive independent or alternative embodiments. Those skilled in the art will appreciate that an embodiment herein may be combined with other embodiments as long as no structural conflicts arise.

[0048] In the description herein, unless otherwise specified or limited, the technical terms "installed," "connected," and "connected" should be understood broadly, and may refer to a movable connection, a fixed connection or integration, or connection via a connector. Those skilled in the art will understand the specific meanings of these terms in the embodiments of this application based on the specific circumstances.

[0049] In the description of this document, terms indicating orientation or positional relationships, such as "up", "down", "left", "right", "horizontal", "vertical", "height", "length", and "width", are intended to accurately describe the embodiments and simplify the description, but are not intended to limit the parts or structures involved to having a specific orientation, being installed or operated in a specific orientation, and should not be understood as limiting the embodiments in this document.

[0050] In the description herein, terms such as "first" and "second" are used only to distinguish different objects and should not be understood to indicate relative importance or to limit the quantity, specific order, or primary and secondary relationship of the described technical features. In the description herein, "plurality" means at least two.

[0051] Embodiments of the present application will now be described in detail with reference to the accompanying drawings. Reference will now be made in detail to preferred embodiments of the present application, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts.

[0052] Figure 1 FIG1 shows a schematic diagram of an insulation resistance detection circuit of an energy storage battery according to an embodiment of the present application. Figure 1 As shown, an insulation resistance detection circuit of an energy storage battery of the present application is connected between a battery 1 and an inverter load 10, comprising:

[0053] Relay 12, connected between the positive electrode of battery 1 and the positive electrode of inverter load 10;

[0054] A first resistor 2, whose first end is connected between the relay 12 and the positive electrode of the inverter load 10, and whose second end is connected in series with the second resistor 3, the first switch 7, and the fourth resistor 5, and finally connected between the negative electrode of the battery 1 and the negative electrode of the inverter load 10;

[0055] A third resistor 4 has a first end connected between the first resistor 2 and the second resistor 3, a second end connected in series with the second switch 8, and ultimately connected between the fourth resistor 5 and the negative electrode of the inverter load 10;

[0056] The third switch 9 has one end connected to the first end of the third resistor 4 and the other end grounded. Figure 1 The PE terminal shown is the grounding terminal;

[0057] The detection circuit also includes a battery management system BMS6; a first terminal of the battery management system BMS6 is connected to the positive electrode of the battery 1, and a second terminal is connected to the negative electrode of the battery 1; a third terminal of the battery management system BMS6 is connected to the relay 12, a fourth terminal of the battery management system BMS6 is connected between the first switch 7 and the fourth resistor 5, a fifth terminal of the battery management system BMS6 is connected to the first switch 7, a sixth terminal of the battery management system BMS6 is connected to the second switch 8, and a seventh terminal of the battery management system BMS6 is connected to the third switch 9;

[0058] The battery management system BMS6 is set to:

[0059] Before starting the insulation resistance test of the energy storage battery 1, it communicates with the inverter load 10. After receiving the insulation test completion signal of the inverter load 10, the insulation resistance test of the energy storage battery 1 is started. As those skilled in the art will understand, almost all batteries and inverters currently on the market are equipped with the function of automatically detecting insulation impedance. The two have no effect when used alone, but they can hardly be used at the same time, because when the battery and the inverter are connected, insulation testing may be performed at the same time, which will cause a false insulation alarm. The present application performs the insulation test of the battery and the inverter in steps. Through the communication between the battery and the inverter, when the inverter itself performs insulation impedance testing, the battery itself does not perform insulation impedance testing. After the inverter self-test is completed, the battery test is started, which effectively avoids this situation.

[0060] Preferably, in some embodiments of the present application, after successfully communicating with the battery 1, the inverter load 10 immediately begins its own insulation test. At this point, the inverter load 10 is in a self-test process. During communication with the inverter load 10, the battery 1 reads the status of the inverter load 10 using a flag in the protocol. If the inverter load 10 is in the self-test state, the battery 1 does not perform insulation impedance testing. Only after the insulation impedance test of the inverter load 10 is complete does the battery 1 begin its own insulation impedance test.

[0061] Control relay 12 is turned on;

[0062] Control the first switch 7, the second switch 8, and the third switch 9 to open, and measure the voltage V of the battery 1 BAT ;

[0063] Control the first switch 7 and the second switch 8 to be turned off, control the third switch 9 to be turned on, and measure the voltage V1 of the battery 1;

[0064] Control the first switch 7, the second switch 8, and the third switch 9 to be turned off, and measure the voltage V2 of the battery 1;

[0065] Calculate the insulation resistance between the positive and negative electrodes of battery 1 based on the following formula:

[0066]

[0067] Among them, Y ISO+ Indicates the insulation resistance value of the positive electrode of battery 1, Y ISO- represents the insulation resistance value of the negative electrode of battery 1, Y1 represents the resistance value of the first resistor 2, Y2 represents the resistance value of the second resistor 3, Y3 represents the resistance value of the third resistor 4, and Y L represents the resistance value of the fourth resistor 5 .

[0068] Specifically, in some embodiments of the present application, the battery management system BMS6 performs alternate switching of the first switch 7, the second switch 8, and the third switch 9 to change the equivalent resistance of the two poles of the battery 1 to the ground, and obtains the unbalanced detection voltage Vsense (V BAT , V1, V2), the battery management system BMS6 will calculate the insulation resistance of the positive and negative electrodes. The voltage Vsense on the positive and negative detection resistors of battery 1 changes with the switching cycle. When the insulation resistance of one electrode of battery 1 becomes lower, the voltage on the detection resistor on that side becomes smaller, and the voltage on the corresponding detection resistor on the other side becomes larger. The specific switching detection steps are as follows:

[0069] S1: Control relay 12 to turn on;

[0070] S2: Open the first switch 7, the second switch 8, and the third switch 9, and measure the voltage V of battery 1 BAT;

[0071] S3: Close the first switch 7 and the second switch 8, wait for about 10ms, measure the voltage of battery 1, and record it as V1;

[0072] S4: Close the first switch 7, the second switch 8, and the third switch 9, wait for about 10ms, measure the voltage of battery 1, and record it as V2;

[0073] S5: End the sampling measurement, through the above measurement value V BAT , V1, V2, use the following formula to calculate the insulation resistance of the positive and negative electrodes of battery 1 to the ground and the casing respectively.

[0074]

[0075] As those skilled in the art will understand, relay 12 is a control relay of the main circuit between the battery and the inverter load, and is mainly used to control the battery charging and discharging path. The relay is disconnected when the battery is shut down. After the battery is turned on and successfully communicates with the inverter, it will remain in a closed and open state. When the battery management system BMS detects a serious alarm in the battery (such as an insulation alarm), it will control the relay to disconnect.

[0076] Preferably, in some embodiments of the present application, the insulation resistance test standard is divided according to the device type or rated voltage;

[0077] 1) The test voltage for low-voltage equipment (≤500V) is usually 500V DC, and the insulation resistance requirement is ≥0.5MΩ or higher. For example, household appliances require ≥10MΩ.

[0078] 2) For medium voltage equipment (500V-10kV) such as motors and cables, the test voltage may be 1000V or 2500V DC. The insulation resistance requirement for 10kV cables is ≥50MΩ for new installations and ≥2MΩ for operating cables.

[0079] For high-voltage equipment (>10kV) such as transformers and power cables, the test voltage is 2500V or 5000V DC, and the insulation resistance requirement is higher, such as ≥600MΩ for a 35kV transformer.

[0080] Preferably, in some embodiments of the present application, the first resistor 2 , the second resistor 3 , the third resistor 4 , and the fourth resistor 5 are all fixed resistors.

[0081] Preferably, in some embodiments of the present application, the battery management system BMS6 is further configured to:

[0082] The insulation resistance value of battery 1 is preset;

[0083] If the insulation resistance value calculated by the detection circuit does not meet the preset standard, a battery fault alarm is issued, the indicator light is on, and battery 1 cannot output voltage or current.

[0084] Specifically, in some embodiments of the present application, the battery management system BMS6 is provided with a power-on detection for the insulation impedance parameters of the battery 1. Before the battery 1 is normally powered on, the battery management system BMS6 performs insulation impedance detection on the entire battery pack through the insulation resistance detection circuit of the embodiment of the present application. The software of the battery management system BMS6 has a preset insulation impedance value, and the actual insulation impedance will be compared with the set value. If the insulation impedance does not meet the standard, the battery 1 will report a serious fault, the yellow light will be on, and the voltage and current will not be able to be output.

[0085] Preferably, in some embodiments of the present application, the insulation resistance detection is set to automatic detection at power-on. Before the battery 1 is powered on, the battery management system BMS6 performs insulation resistance detection on the entire battery 1 through a detection circuit.

[0086] Preferably, in some embodiments of the present application, it is necessary to wait for at least 10 ms before measuring the voltages V1 and V2 of the battery 1 .

[0087] Preferably, in some embodiments of the present application, a Hall sensor 11 is further provided, connected between the negative electrode of the battery 1 and the second terminal of the battery management system BMS6; and further connected to the eighth terminal of the battery management system BMS6. The Hall sensor 11 is used to detect whether there is current in the circuit. If the insulation test is not performed or the insulation test fails, if the Hall sensor 11 detects the presence of current, the battery management system BMS6 will immediately shut down the relay 12 of the main circuit to ensure safety.

[0088] According to another aspect of the present application, the present application further provides a method for controlling an insulation resistance detection circuit of an energy storage battery, comprising the detection circuit of any one of the above embodiments:

[0089] Before starting the insulation resistance test of the energy storage battery 1, the battery management system BMS6 communicates with the inverter load 10. After receiving the insulation test completion signal from the inverter load 10, it starts the insulation resistance test of the energy storage battery 1. As those skilled in the art will understand, the insulation resistance of the battery 1 and the inverter load 10 will not be tested at the same time, and will not affect each other, thus avoiding the possibility of false insulation alarms from the battery 1 or the inverter load 10, resulting in malfunction.

[0090] Control relay 12 is turned on;

[0091] Control the first switch 7, the second switch 8, and the third switch 9 to open, and measure the voltage V of the battery 1 BAT ;

[0092] Control the first switch 7 and the second switch 8 to be turned off, control the third switch 9 to be turned on, and measure the voltage V1 of the battery 1;

[0093] Control the first switch 7, the second switch 8, and the third switch 9 to be turned off, and measure the voltage V2 of the battery 1;

[0094] Calculate the insulation resistance between the positive and negative electrodes of battery 1 based on the following formula:

[0095]

[0096] Among them, Y ISO+ Indicates the insulation resistance value of the positive electrode of battery 1, Y ISO- represents the insulation resistance value of the negative electrode of battery 1, Y1 represents the resistance value of the first resistor 2, Y2 represents the resistance value of the second resistor 3, Y3 represents the resistance value of the third resistor 4, and Y L represents the resistance value of the fourth resistor 5 .

[0097] Preferably, in some embodiments of the present application, the battery management system BMS6 is preset with the insulation resistance value of the battery 1; if the insulation resistance value calculated by the detection circuit does not meet the preset standard, a battery fault alarm is issued, the indicator light is on, and the battery 1 cannot output voltage or current. Specifically, in some embodiments of the present application, the battery management system BMS6 is provided with a power-on detection for the insulation resistance parameter of the battery 1. Before the battery 1 is normally powered on, the battery management system BMS6 performs insulation resistance detection on the entire battery pack through the insulation resistance detection circuit of the embodiment of the present application. The insulation resistance value is preset in the software of the battery management system BMS6, and the actual insulation resistance will be compared with the set value. If the insulation resistance does not meet the standard, the battery 1 will report a serious fault, the yellow light will be on, and it will be unable to output voltage or current.

[0098] Preferably, in some embodiments of the present application, the insulation resistance test is configured as an automatic test at power-up. Before the battery 1 is powered on, the battery management system (BMS6) performs an insulation resistance test on the entire battery 1 via a detection circuit. As will be appreciated by those skilled in the art, the battery 1 will perform its own insulation test upon power-up. If the insulation resistance does not meet the standard, the battery 1 will not output voltage to prevent leakage. After the battery 1 is normally powered on and has already output voltage, the insulation resistance test will no longer be performed.

[0099] According to another aspect of the present application, the present application further provides a computer-readable storage medium having computer instructions stored thereon. When the computer instructions are executed by a processor, the detection circuit control method provided by any one of the above embodiments can be implemented.

[0100] The present application discloses an insulation resistance detection circuit, control method, and storage medium for an energy storage battery. The present application incorporates an intelligent detection program into the circuit design, significantly improving the safety and detection reliability of the battery system. The present application adopts a fully automatic detection mechanism, and the detection process is automatically completed when the device is turned on, without the need for manual intervention, reducing operational risks, effectively ensuring personal safety, and preventing electric shock accidents. The present application can monitor the insulation status of the equipment in real time and accurately identify leakage phenomena. The present application intelligently identifies the actual working conditions of the battery system and the load equipment by setting up real-time communication between the battery and the inverter load through two-way data interaction, thereby solving the industry pain point that the system cannot be used normally due to false alarms, and greatly improving detection efficiency and system availability while ensuring safety.

[0101] The above describes the preferred embodiments of the present application. It should be understood that the present application is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-mentioned disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the present application without departing from the scope of the technical solutions of the present application, or modify them into equivalent embodiments with equivalent changes, which does not affect the substantive content of the present application. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application that do not depart from the content of the technical solutions of the present application are still within the scope of protection of the technical solutions of the present application.

Claims

1. The insulation resistance detection circuit of the energy storage battery is characterized in that: The detection circuit is connected between the battery and the inverter load, and includes: a relay connected between the positive electrode of the battery and the positive electrode of the inverter load; a first resistor, a first end of which is connected between the relay and the positive electrode of the inverter load, a second end of which is connected in series with a second resistor, a first switch, and a fourth resistor, and finally connected between the negative electrode of the battery and the negative electrode of the inverter load; a third resistor, a first end of which is connected between the first resistor and the second resistor, a second end of which is connected in series with a second switch, and finally connected between the fourth resistor and the negative electrode of the inverter load; a third switch, one end of which is connected to the first end of the third resistor and the other end of which is grounded; The detection circuit further includes a battery management system (BMS); a first terminal of the battery management system (BMS) is connected to the positive electrode of the battery, a second terminal is connected to the negative electrode of the battery, a third terminal is connected to the relay, a fourth terminal is connected between the first switch and the fourth resistor, a fifth terminal is connected to the first switch, a sixth terminal is connected to the second switch, and a seventh terminal is connected to the third switch. The battery management system BMS is configured as follows: Before starting the insulation resistance test of the energy storage battery, communicating with the inverter load, and starting the insulation resistance test of the energy storage battery after receiving the insulation test completion signal of the inverter load; Controlling the relay to be turned on; Control the first switch, the second switch, and the third switch to be turned on, and measure the battery voltage V BAT ; Controlling the first switch and the second switch to be turned off, controlling the third switch to be turned on, and measuring the battery voltage V1; controlling the first switch, the second switch, and the third switch to be turned off, and measuring the battery voltage V2; The insulation resistance values ​​of the positive and negative electrodes of the battery are calculated based on the following formula: Among them, Y ISO+ Indicates the insulation resistance value of the battery positive electrode, Y ISO- Indicates the insulation resistance value of the negative electrode of the battery, Y1 indicates the resistance value of the first resistor, Y2 indicates the resistance value of the second resistor, Y3 indicates the resistance value of the third resistor, and Y L represents the resistance value of the fourth resistor.

2. The detection circuit according to claim 1, characterized in that The first resistor, the second resistor, the third resistor, and the fourth resistor are all fixed resistors.

3. The detection circuit according to claim 1, characterized in that: The battery management system BMS is further configured to: The insulation resistance value of the battery is preset; If the insulation resistance value calculated by the detection circuit does not meet the preset standard, a battery failure alarm is issued, an indicator light is turned on, and the battery cannot output voltage or current.

4. The detection circuit according to claim 1, characterized in that: The insulation resistance detection is set to be automatic detection at startup. Before the battery is started, the battery management system BMS performs insulation resistance detection on the entire battery through the detection circuit.

5. The detection circuit according to claim 1, wherein: Before measuring the battery voltages V1 and V2, it is necessary to wait for at least 10 ms.

6. The detection circuit according to claim 1, characterized in that: A Hall sensor is also provided, connected between the negative electrode of the battery and the second end of the battery management system BMS; and is also connected to the eighth end of the battery management system BMS.

7. A method for controlling an insulation resistance detection circuit of an energy storage battery, characterized in that: The detection circuit according to any one of claims 1 to 6: The battery management system BMS communicates with the inverter load before starting the insulation resistance test of the energy storage battery, and starts the insulation resistance test of the energy storage battery after receiving the insulation test completion signal from the inverter load; Controlling the relay to be turned on; Control the first switch, the second switch, and the third switch to be turned on, and measure the battery voltage V BAT ; Controlling the first switch and the second switch to be turned off, controlling the third switch to be turned on, and measuring the battery voltage V1; controlling the first switch, the second switch, and the third switch to be turned off, and measuring the battery voltage V2; The insulation resistance values ​​of the positive and negative electrodes of the battery are calculated based on the following formula: Among them, Y ISO+ Indicates the insulation resistance value of the battery positive electrode, Y ISO- Indicates the insulation resistance value of the negative electrode of the battery, Y1 indicates the resistance value of the first resistor, Y2 indicates the resistance value of the second resistor, Y3 indicates the resistance value of the third resistor, and Y L represents the resistance value of the fourth resistor.

8. The detection circuit control method according to claim 7, characterized in that: The battery management system BMS is preset with the insulation resistance value of the battery; If the insulation resistance value calculated by the detection circuit does not meet the preset standard, a battery failure alarm is issued, an indicator light is turned on, and the battery cannot output voltage or current.

9. The detection circuit control method according to claim 7, characterized in that: The insulation resistance detection is set to be automatic detection at startup. Before the battery is started, the battery management system BMS performs insulation resistance detection on the entire battery through the detection circuit.

10. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are executed by a processor, the detection circuit control method according to any one of claims 7 to 9 is implemented.

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