Insulation resistor detection device and energy storage cabinet

Abstract

The invention discloses an insulation resistance detection device and an energy storage cabinet, and belongs to the technical field of energy storage, and the device comprises a bridge arm circuit which is connected with a sampling resistor and a change-over switch in series, and is used for carrying out the insulation resistance detection of a battery cluster in a target energy storage cabinet; the control chip is connected with the bridge arm circuit and is used for controlling the sampling resistor and the change-over switch through different switch time sequences so as to trigger the bridge arm circuit to carry out insulation resistance detection on the battery cluster; the isolation ADC circuit is connected with the control chip and used for converting the control signal sent by the control chip into a target digital signal; and the signal conditioning circuit is used for performing signal processing on the target digital signal to obtain a target processing signal so as to assist the control chip to complete insulation resistance detection on the battery cluster by using the target processing signal. By means of the device, the problems that in the prior art, when insulation resistance detection is conducted on the battery cluster, detection precision is poor, and safety is not high can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage, and particularly relates to a detection device for insulation resistance and an energy storage cabinet. Background Art

[0002] The detection of the insulation resistance of a battery cluster plays an important role in the safe and stable operation of an energy storage cabinet. The detection of the insulation resistance of a battery cluster refers to measuring the insulation resistance between the positive and negative poles of the battery cluster and the ground, and evaluating the insulation performance of the energy storage cabinet according to the measurement results.

[0003] In the prior art, a balanced bridge or an unbalanced bridge is usually used to detect the insulation resistance of the battery cluster in the energy storage cabinet. When using a balanced bridge or an unbalanced bridge to detect the insulation resistance of the battery cluster, a sampling resistor and a switching switch are usually connected in parallel on the resistor bridge arm of the balanced bridge or the unbalanced bridge, and then the insulation of the battery cluster is detected by collecting the voltage value on the sampling resistor. When the sampling resistor and the switching switch are connected in parallel on the resistor bridge arm of the balanced bridge, it will affect the balance condition of the balanced bridge, thereby affecting the detection accuracy of the insulation resistance of the battery cluster by the balanced bridge. When the sampling resistor and the switching switch are connected in parallel on the resistor bridge arm of the unbalanced bridge, it will change the resistance value output of the unbalanced bridge, which will also affect the detection accuracy of the insulation resistance of the battery cluster by the unbalanced bridge. Moreover, an isolation circuit is not provided in the existing battery cluster insulation resistance detection circuit, and electrical isolation between strong electricity and weak electricity cannot be achieved, so the safety and reliability during the detection of the insulation resistance of the battery cluster cannot be guaranteed. Currently, there is no relatively effective solution to this technical problem. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a detection device for insulation resistance and an energy storage cabinet to solve the problems of poor detection accuracy and low safety in detecting the insulation resistance of the battery cluster in the energy storage cabinet in the prior art. The specific solutions are as follows:

[0005] To solve the above technical problems, the present invention provides a detection device for insulation resistance, including:

[0006] A bridge arm circuit connected in series with a sampling resistor and a switching switch, which is used to detect the insulation resistance of the battery cluster in the target energy storage cabinet; the bridge arm circuit is specifically a balanced bridge or an unbalanced bridge;

[0007] A control chip, connected to the bridge arm circuit, which is used to control the sampling resistor and the switching switch through different switching timings to trigger the bridge arm circuit to detect the insulation resistance of the battery cluster;

[0008] An isolation ADC circuit, connected to the control chip, which is used to convert the control signal sent by the control chip into a target digital signal;

[0009] A signal conditioning circuit, connected between the isolation ADC circuit and the bridge arm circuit, is configured to perform signal processing on the target digital signal to obtain a target processed signal, so as to assist the control chip to complete the insulation resistance detection of the battery cluster by using the target processed signal.

[0010] Preferably, the isolation ADC circuit includes: an ADC chip and an isolation device, and the ADC chip is connected to the control chip through the isolation device.

[0011] Preferably, the isolation device is specifically an isolation optocoupler or an isolation communication chip.

[0012] Preferably, the isolation ADC circuit is specifically an isolation ADC chip.

[0013] Preferably, the sampling resistor includes a first resistor and a second resistor, and the switching switch includes a first relay and a second relay.

[0014] Preferably, both the first relay and the second relay are isolation optocoupler relays.

[0015] Preferably, the balanced bridge includes: the first resistor, the second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, the first relay, and the second relay;

[0016] Wherein, two output terminals of the control chip are respectively connected to the control terminals of the first relay and the second relay. The first end of the first resistor is respectively connected to the first output terminal of the signal conditioning circuit and the first end of the first relay. The second end of the first relay is connected to the first end of the third resistor. The second end of the third resistor is connected to the first end of the seventh resistor. The second end of the first resistor is respectively connected to the second output terminal of the signal conditioning circuit, the first end of the second relay, and the first end of the fifth resistor. The second end of the fifth resistor is connected to the first end of the sixth resistor. The second end of the second relay is connected to the first end of the fourth resistor. The second end of the fourth resistor is connected to the first end of the eighth resistor. The second end of the eighth resistor is respectively connected to the second ends of the sixth resistor and the seventh resistor. The second end of the eighth resistor is grounded. The seventh resistor and the eighth resistor are respectively the total positive-to-ground impedance and the total negative-to-ground impedance of the battery cluster.

[0017] Preferably, the resistance values of the first resistor, the second resistor, and the sixth resistor are equal, and the resistance values of the third resistor, the fourth resistor, and the fifth resistor are equal.

[0018] Preferably, the unbalanced bridge includes: the first resistor, the second resistor, the ninth resistor, the tenth resistor, the first relay, and the second relay;

[0019] Wherein, two output terminals of the control chip are respectively connected to the control terminals of the first relay and the second relay. The first end of the first resistor is respectively connected to the first output terminal of the signal conditioning circuit and the first end of the first relay. The second end of the first relay is connected to the first end of the ninth resistor. The second end of the ninth resistor is connected to the first end of the eleventh resistor. The second end of the first resistor is respectively connected to the first end of the second resistor and the second output terminal of the signal conditioning circuit. The second end of the second resistor is connected to the first output terminal of the second relay. The second output terminal of the second relay is connected to the first end of the tenth resistor. The second end of the tenth resistor is connected to the first end of the twelfth resistor. The second end of the twelfth resistor is connected to the second end of the eleventh resistor. The second ends of the first resistor and the twelfth resistor are both grounded. The eleventh resistor and the twelfth resistor are respectively the total positive-to-ground impedance and the total negative-to-ground impedance of the battery cluster.

[0020] To solve the above technical problems, the present invention also provides an energy storage cabinet, including a detection device for insulation resistance as disclosed above.

[0021] Compared with the prior art, in the insulation resistance detection device provided by the present invention, since the sampling resistor and the switching switch are directly connected in series on the bridge arm circuit, where the bridge arm circuit is specifically a balanced bridge or an unbalanced bridge, this is equivalent to making the sampling resistor and the switching switch become a part of the balanced bridge or the unbalanced bridge. In this setting method, it will neither affect the balance condition of the balanced bridge nor change the resistance output of the unbalanced bridge. Moreover, when the sampling resistor and the switching switch are connected in series on the balanced bridge or the unbalanced bridge, and the control chip controls the sampling resistor and the switching switch to trigger the bridge arm circuit to detect the insulation resistance of the battery cluster in the energy storage cabinet through different switch timings, it can also avoid the deviation existing when all the resistors on the resistor bridge arm participate in the sampling resistor voltage division detection. In this way, the accuracy of detecting the insulation resistance of the battery cluster in the energy storage cabinet by using the balanced bridge or the unbalanced bridge can be significantly improved. In addition, in the insulation resistance detection device provided by the present invention, an isolation ADC circuit is also provided between the control chip and the signal conditioning circuit, so that the strong electricity and the weak electricity can be insulated and isolated, thereby ensuring the safety and reliability during the insulation resistance detection of the battery cluster.

[0022] Correspondingly, an energy storage cabinet provided by the present invention also has the above beneficial effects. Description of the Drawings

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained according to the provided accompanying drawings.

[0024] Figure 1 Structural diagram of a detection device for insulation resistance provided by an embodiment of the present invention;

[0025] Figure 2 Structural diagram of another detection device for insulation resistance provided by an embodiment of the present invention;

[0026] Figure 3 Structural diagram of yet another detection device for insulation resistance provided by an embodiment of the present invention. Detailed implementation manners

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0028] Please refer to Figure 1 , Figure 1 Structural diagram of a detection device for insulation resistance provided by an embodiment of the present invention. The device includes:

[0029] A bridge arm circuit 10 in series with a sampling resistor 101 and a switching switch 102, which is used to detect the insulation resistance of the battery cluster in the target energy storage cabinet; the bridge arm circuit 10 is specifically a balanced bridge or an unbalanced bridge;

[0030] A control chip 11, connected to the bridge arm circuit 10, which is used to control the sampling resistor 101 and the switching switch 102 through different switch timings to trigger the bridge arm circuit 10 to detect the insulation resistance of the battery cluster;

[0031] An isolation ADC circuit 12, connected to the control chip 11, which is used to convert the control signal sent by the control chip 11 into a target digital signal;

[0032] A signal conditioning circuit 13, connected between the isolation ADC circuit 12 and the bridge arm circuit 10, which is used to perform signal processing on the target digital signal to obtain a target processing signal, so as to assist the control chip 11 to complete the detection of the insulation resistance of the battery cluster by using the target processing signal.

[0033] In this embodiment, a detection device for insulation resistance is provided. Using this device can not only improve the accuracy of detecting the insulation resistance of the battery cluster in the energy storage cabinet, but also ensure the safety and reliability of detecting the insulation resistance of the battery cluster in the energy storage cabinet.

[0034] The detection device is provided with a bridge arm circuit 10, a control chip 11, an isolation ADC (Analog to Digital Converter) circuit 12, and a signal conditioning circuit 13. Among them, the bridge arm circuit 10 can be either a balanced bridge or an unbalanced bridge. The bridge arm circuit 10 is used to detect the insulation resistance of the battery cluster in the target energy storage cabinet. And in this embodiment, the sampling resistor 101 and the switching switch 102 are both connected in series on the resistance bridge arm of the bridge arm circuit 10.

[0035] When the sampling resistor 101 and the switching switch 102 are both connected in series on the resistance bridge arm of the bridge arm circuit 10, the sampling resistor 101 and the switching switch 102 are equivalent to a part of the balanced bridge or the unbalanced bridge. In such a setting method, it will neither affect the balance condition of the balanced bridge nor change the resistance value output of the unbalanced bridge.

[0036] Moreover, when the control chip 11 controls the sampling resistor 101 and the switching switch 102 through different switching timings to trigger the bridge arm circuit 10 to detect the insulation resistance of the battery cluster, since not all the resistors on the resistance bridge arm of the balanced bridge or the unbalanced bridge will be connected to the detection circuit under different switching timings, when the control chip 11 detects the insulation resistance of the battery cluster in the target energy storage cabinet, it can avoid the deviation existing when all the resistors on the resistance bridge arm participate in the sampling resistor voltage division detection. Thus, it can significantly improve the accuracy of detecting the insulation resistance of the battery cluster in the energy storage cabinet using the balanced bridge or the unbalanced bridge.

[0037] Specifically, when the control chip 11 controls the sampling resistor 101 and the switching switch 102 through different switching timings to trigger the bridge arm circuit 10 to detect the insulation resistance of the battery cluster, by collecting the voltage value across the sampling resistor 101, it can infer the insulation resistance value of the battery cluster based on the change in the voltage value of the sampling resistor 101, and then realize the detection of the insulation resistance of the battery cluster. Since the core inventive point of the present invention lies in the improvement of the insulation resistance detection structure of the battery cluster, the detection method of the insulation resistance of the battery cluster is not the core content of the present invention, and inferring the insulation resistance value of the battery cluster based on the change in the voltage value of the sampling resistor 101 is common knowledge in the art, so it will not be specifically described here.

[0038] During the process of the control chip 11 triggering the bridge arm circuit 10 to detect the insulation resistance of the battery cluster, the isolation ADC circuit 12 will first convert the control signal sent by the control chip 11 into a target digital signal. Then, the signal conditioning circuit 13 will perform signal processing on the target digital signal to obtain a target processed signal. Among them, when the signal conditioning circuit 13 performs signal processing on the target digital signal, it mainly performs signal filtering and signal amplification processing on the target digital signal, so as to assist the control chip 11 to complete the insulation resistance detection of the battery cluster.

[0039] In practical applications, the control chip 11 can be set as an MCU (Microcontroller Unit). Because the MCU not only has the advantages of low power consumption and high integration, but also the development of the MCU mainly focuses on software programming and the hardware design is relatively simple. Therefore, when the control chip 11 is set as an MCU, it can not only reduce the power consumption of the detection device and the occupancy of the space volume, but also reduce the construction difficulty of the detection device.

[0040] It can be imagined that when the isolation ADC circuit 12 is set between the control chip 11 and the signal conditioning circuit 13, the isolation ADC circuit 12 can be used to insulate and isolate the strong electricity and weak electricity in the detection environment, so as to ensure the safety and reliability when using this detection device to detect the insulation resistance of the battery cluster in the energy storage cabinet.

[0041] Obviously, in the insulation resistance detection device provided in this embodiment, since the sampling resistor and the switching switch are directly connected in series on the bridge arm circuit, where the bridge arm circuit is specifically a balanced bridge or an unbalanced bridge, this is equivalent to making the sampling resistor and the switching switch become a part of the balanced bridge or the unbalanced bridge. In this setting method, it will neither affect the balance condition of the balanced bridge nor change the resistance output of the unbalanced bridge. And when the sampling resistor and the switching switch are connected in series on the balanced bridge or the unbalanced bridge, and the control chip controls the sampling resistor and the switching switch to trigger the bridge arm circuit to detect the insulation resistance of the battery cluster in the energy storage cabinet through different switch timings, it can also avoid the deviation existing when all the resistors on the resistor bridge arm participate in the sampling resistor voltage division detection, so as to significantly improve the accuracy when using the balanced bridge or the unbalanced bridge to detect the insulation resistance of the battery cluster in the energy storage cabinet. In addition, in the insulation resistance detection device provided in this embodiment, an isolation ADC circuit is also set between the control chip and the signal conditioning circuit, so that the strong electricity and weak electricity can be insulated and isolated, thereby ensuring the safety and reliability when detecting the insulation resistance of the battery cluster.

[0042] Based on the above embodiments, this embodiment further describes and optimizes the technical solution. As a preferred implementation, the isolated ADC circuit 12 includes: an ADC chip and an isolation device, and the ADC chip is connected to the control chip through the isolation device.

[0043] In practical applications, the isolated ADC circuit 12 can be set as a discrete device, that is, the isolated ADC circuit 12 is built using an ADC chip and an isolation device. Since the ADC chip and the isolation device in the isolated ADC circuit 12 are independent of each other and are discrete devices, if a certain component in the discrete device is damaged, the damaged component can be replaced and repaired separately. This can not only reduce the repair cost required for repairing the isolated ADC circuit 12, but also reduce the difficulty of repairing the isolated ADC circuit 12.

[0044] As a preferred implementation, the isolation device is specifically an isolation optocoupler or an isolation communication chip.

[0045] Specifically, in practical applications, the isolation device can be set as an isolation optocoupler. Because the isolation optocoupler achieves electrical isolation between the input side and the output side through the transmission of optical signals, and there is no direct electrical connection relationship between its input side and output side, when the isolation device is set as an isolation optocoupler, it can effectively prevent damage to low-voltage devices caused by high-voltage currents.

[0046] Alternatively, the isolation device can also be set as an isolation communication chip. Because the isolation communication chip is usually manufactured using advanced isolation technologies and high-quality manufacturing processes, it can work stably in harsh environments and has high reliability and anti-interference capabilities. Therefore, when the isolation device is set as an isolation communication chip, the reliability of the isolated ADC circuit 12 during signal transmission can be relatively improved.

[0047] Based on the above embodiments, this embodiment further describes and optimizes the technical solution. As a preferred implementation, the isolated ADC circuit 12 is specifically an isolated ADC chip.

[0048] Because the isolated ADC chip is an integrated chip, it not only has the advantages of low setting cost and less material consumption, but also is more convenient to be packaged in the insulation resistance detection device. Therefore, in this embodiment, the isolated ADC circuit 12 can be set as an isolated ADC chip to further reduce the design cost and manufacturing difficulty required for the insulation resistance detection device.

[0049] Based on the above embodiments, the present embodiment further describes and optimizes the technical solution. As a preferred implementation manner, the sampling resistor 101 includes a first resistor and a second resistor, and the switching switch 102 includes a first relay and a second relay.

[0050] In practical applications, when detecting the insulation resistance of the battery cluster in the target energy storage cabinet, it is mainly to detect the total positive-to-ground impedance and the total negative-to-ground impedance of the battery cluster. Therefore, in order to reduce the number of sampling resistors 101 and switching switches 102 in the detection device, the number of sampling resistors 101 is set to two, and the number of switching switches 102 is set to two. That is, the sampling resistor 101 includes a first resistor and a second resistor, and the switching switch 102 includes a first relay and a second relay.

[0051] As a preferred implementation manner, both the first relay and the second relay are isolated optocoupler relays.

[0052] Since the isolated optocoupler relay realizes the electrical isolation between the input signal and the output signal through an optocoupler, it can effectively prevent the damage of high-voltage current to the low-voltage circuit. And, the isolated optocoupler relay uses optical signals to transmit signals and is insensitive to electromagnetic interference and radio frequency interference, so that the isolated optocoupler relay can work stably in a complex electromagnetic environment. Therefore, in the present embodiment, both the first relay and the second relay are set as isolated optocoupler relays. In practical applications, the isolated optocoupler relay can be set as QCPL-A58JV-500E.

[0053] In addition, compared with the contacts of mechanical relays that are easily worn during frequent switching, since the isolated optocoupler relay uses optical signals to achieve electrical isolation between the input side and the output side, it can avoid the wear of the isolated optocoupler relay during use. Therefore, when both the first relay and the second relay are set as isolated optocoupler relays, the service life of the first relay and the second relay can be significantly improved.

[0054] Please refer to Figure 2 , Figure 2 which is the structural diagram of another insulation resistance detection device provided by the embodiment of the present invention. As a preferred implementation manner, the balance bridge includes: a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a first relay Q1 and a second relay Q2;

[0055] Among them, the two output terminals of the control chip 11 are respectively connected to the control terminal of the first relay Q1 and the control terminal of the second relay Q2. The first end of the first resistor R1 is respectively connected to the first output terminal of the signal conditioning circuit 13 and the first end of the first relay Q1. The second end of the first relay Q1 is connected to the first end of the third resistor R3. The second end of the third resistor R3 is connected to the first end of the seventh resistor R7. The second end of the first resistor R1 is respectively connected to the second output terminal of the signal conditioning circuit 13, the first end of the second relay Q2, and the first end of the fifth resistor R5. The second end of the fifth resistor R5 is connected to the first end of the sixth resistor R6. The second end of the second relay Q2 is connected to the first end of the fourth resistor R4. The second end of the fourth resistor R4 is connected to the first end of the eighth resistor R8. The second end of the eighth resistor R8 is respectively connected to the second end of the sixth resistor R6 and the second end of the seventh resistor R7. The second end of the eighth resistor R8 is grounded. The seventh resistor R7 and the eighth resistor R8 are respectively the total positive-to-ground impedance and the total negative-to-ground impedance of the battery cluster.

[0056] In this embodiment, a specific description is given of the balanced bridge. In this balanced bridge, the first resistor R1 and the second resistor R2 are sampling resistors, that is, the first resistor R1 and the second resistor R2 in the balanced bridge act as sampling resistors. In this setting method, it is equivalent to reusing the first resistor R1 and the second resistor R2 in the balanced bridge as the sampling resistors in the detection device, so that the number of resistors set in the detection device can be relatively reduced.

[0057] When the control chip 11 outputs a high level, it will drive the first relay Q1 and the second relay Q2 respectively. When the first relay Q1 is closed and the second relay Q2 is open, the first voltage value across the first resistor R1 is collected. When the first relay Q1 is closed and the second relay Q2 is closed, the second voltage value across the first resistor R1 is collected. Then, by substituting the two collected voltage values into the relevant calculation formula, the insulation resistance of the battery cluster can be calculated, and thus the purpose of detecting the insulation resistance of the battery cluster can be achieved. Obviously, when detecting the insulation resistance of the battery cluster, the above method can avoid the errors existing when all the resistors on the resistor bridge arm participate in the voltage division detection. Therefore, the accuracy of detecting the insulation resistance of the battery cluster can be significantly improved by this method.

[0058] Moreover, when the detection of the insulation resistance of the battery cluster is completed, the first relay Q1 and the second relay Q2 are disconnected, and the balanced bridge is decoupled from the bus, which will not affect the accuracy of detecting the insulation resistance of other devices in the energy storage cabinet either. Among them, the line where the seventh resistor R7 and the eighth resistor R8 are located is the bus.

[0059] As a preferred embodiment, the resistance values of the first resistor R1, the second resistor R2, and the sixth resistor R6 are equal, and the resistance values of the third resistor R3, the fourth resistor R4, and the fifth resistor R5 are equal.

[0060] In this embodiment, the first resistor R1, the second resistor R2, and the sixth resistor R6 are set to the same resistor, and the third resistor R3, the fourth resistor R4, and the fifth resistor R5 are set to the same resistor. Because in this setting method, the current values in the balance bridge can be made equal during the time-division conduction of the first relay Q1 and the second relay Q2, thereby further improving the accuracy when using the balance bridge to detect the insulation resistance of the battery cluster.

[0061] Please refer to Figure 3 , Figure 3 which is a structural diagram of another insulation resistance detection device provided by the embodiment of the present invention. As a preferred embodiment, the unbalanced bridge includes: a first resistor R1, a second resistor R2, a ninth resistor R9, a tenth resistor R10, a first relay Q1, and a second relay Q2;

[0062] Among them, the two output terminals of the control chip 11 are respectively connected to the control terminals of the first relay Q1 and the second relay Q2. The first end of the first resistor R1 is respectively connected to the first output terminal of the signal conditioning circuit 13 and the first end of the first relay Q1. The second end of the first relay Q1 is connected to the first end of the ninth resistor R9. The second end of the ninth resistor R9 is connected to the first end of the eleventh resistor R11. The second end of the first resistor R1 is respectively connected to the first end of the second resistor R2 and the second output terminal of the signal conditioning circuit 13. The second end of the second resistor R2 is connected to the first output terminal of the second relay Q2. The second output terminal of the second relay Q2 is connected to the first end of the tenth resistor R10. The second end of the tenth resistor R10 is connected to the first end of the twelfth resistor R12. The second end of the twelfth resistor R12 is connected to the second end of the eleventh resistor R11. The second ends of the first resistor R1 and the twelfth resistor R12 are both grounded. The eleventh resistor R11 and the twelfth resistor R12 are respectively the total positive-to-ground impedance and the total negative-to-ground impedance of the battery cluster.

[0063] In this embodiment, the unbalanced bridge is specifically described. Among them, the first resistor R1 and the second resistor R2 in the unbalanced bridge act as sampling resistors, that is, the sampling resistors in the detection device reuse the first resistor and the second resistor in the unbalanced bridge, so that the number of resistors set in the detection device can be relatively reduced.

[0064] When the control chip 11 outputs a high level, the first relay Q1 and the second relay Q2 start to work. When the first relay Q1 is closed and the second relay Q2 is open, the first voltage value across the first resistor R1 is collected; when the first relay Q1 is closed and the second relay Q2 is closed, the second voltage value across the first resistor R1 is collected; then, the two collected voltage values are substituted into the relevant calculation formula to calculate the insulation resistance of the battery cluster, and thus the purpose of detecting the insulation resistance of the battery cluster can be achieved. Obviously, when detecting the insulation resistance of the battery cluster by the above method, the error existing when all the resistors on the resistor bridge arm participate in the voltage division detection can be avoided, so that the accuracy of detecting the insulation resistance of the battery cluster can be significantly improved.

[0065] Moreover, when the detection of the insulation resistance of the battery cluster is completed, the first relay Q1 and the second relay Q2 are in an open circuit state, and the unbalanced bridge is decoupled from the bus, which will not affect the accuracy of detecting the insulation resistance of other devices in the energy storage cabinet either. Among them, the circuit where the eleventh resistor R11 and the twelfth resistor R12 are located is the bus.

[0066] Correspondingly, an embodiment of the present invention further provides an energy storage cabinet, including a detection device for an insulation resistance as disclosed above.

[0067] The energy storage cabinet provided by the embodiment of the present invention has the beneficial effects of a detection device for an insulation resistance as disclosed above.

[0068] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0069] Finally, it should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of another identical element in the process, method, article or device including the element.

[0070] The above has introduced in detail a detection device for insulation resistance and an energy storage cabinet provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A detecting device for insulation resistance, characterized in that, Including: An arm circuit in series with a sampling resistor and a switching switch, which is used to detect the insulation resistance of the battery cluster in the target energy storage cabinet; the arm circuit is specifically a balanced bridge or an unbalanced bridge; A control chip, connected to the arm circuit, which is used to control the sampling resistor and the switching switch through different switching timings to trigger the arm circuit to detect the insulation resistance of the battery cluster; An isolated ADC circuit, connected to the control chip, which is used to convert the control signal sent by the control chip into a target digital signal; A signal conditioning circuit, connected between the isolated ADC circuit and the arm circuit, which is used to process the target digital signal to obtain a target processed signal, so as to assist the control chip to complete the insulation resistance detection of the battery cluster by using the target processed signal.

2. The detecting device for insulation resistance according to claim 1, characterized in that, The isolated ADC circuit includes: an ADC chip and an isolation device, and the ADC chip is connected to the control chip through the isolation device.

3. The detection device for insulation resistance according to claim 2, wherein, The isolation device is specifically an isolation optocoupler or an isolation communication chip.

4. The detecting device for insulation resistance according to claim 1, characterized in that, The isolated ADC circuit is specifically an isolated ADC chip.

5. The detection device for insulation resistance according to claim 1, wherein, The sampling resistor includes a first resistor and a second resistor, and the switching switch includes a first relay and a second relay.

6. The detecting device for insulation resistance according to claim 5, wherein, Both the first relay and the second relay are isolation optocoupler relays.

7. The detection device for insulation resistance according to claim 5, characterized in that, The balanced bridge includes: the first resistor, the second resistor, the third resistor, the fourth resistor, the fifth resistor, the sixth resistor, the first relay and the second relay; Wherein, two output terminals of the control chip are respectively connected to the control terminals of the first relay and the second relay, the first end of the first resistor is respectively connected to the first output terminal of the signal conditioning circuit and the first end of the first relay, the second end of the first relay is connected to the first end of the third resistor, the second end of the third resistor is connected to the first end of the seventh resistor, the second end of the first resistor is respectively connected to the second output terminal of the signal conditioning circuit, the first end of the second relay and the first end of the fifth resistor, the second end of the fifth resistor is connected to the first end of the sixth resistor; the second end of the second relay is connected to the first end of the fourth resistor, the second end of the fourth resistor is connected to the first end of the eighth resistor, and the second end of the eighth resistor is respectively connected to the second ends of the sixth resistor and the seventh resistor; the second end of the eighth resistor is grounded; the seventh resistor and the eighth resistor are respectively the total positive-to-ground impedance and the total negative-to-ground impedance of the battery cluster.

8. The detecting device for insulation resistance according to claim 7, characterized in that, The resistance values of the first resistor, the second resistor and the sixth resistor are equal, and the resistance values of the third resistor, the fourth resistor and the fifth resistor are equal.

9. The detecting device for insulation resistance according to claim 5, wherein The unbalanced bridge includes: the first resistor, the second resistor, the ninth resistor, the tenth resistor, the first relay and the second relay; Among them, two output terminals of the control chip are respectively connected to a control terminal of the first relay and a control terminal of the second relay. A first end of the first resistor is respectively connected to a first output terminal of the signal conditioning circuit and a first end of the first relay. A second end of the first relay is connected to a first end of the ninth resistor. A second end of the ninth resistor is connected to a first end of the eleventh resistor. A second end of the first resistor is respectively connected to a first end of the second resistor and a second output terminal of the signal conditioning circuit. A second end of the second resistor is connected to a first output terminal of the second relay. A second output terminal of the second relay is connected to a first end of the tenth resistor. A second end of the tenth resistor is connected to a first end of the twelfth resistor. A second end of the twelfth resistor is connected to a second end of the eleventh resistor. The second end of the first resistor and the second end of the twelfth resistor are both grounded. The eleventh resistor and the twelfth resistor are respectively the total positive-to-ground impedance and the total negative-to-ground impedance of the battery cluster.

10. A energy storage cabinet, characterized in that, Comprising a detecting device for insulation resistance according to any one of claims 1 to 9.

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