An insulation detection device

Abstract

The application discloses an insulation detection device for detecting the insulation resistance value of an energy storage system, which comprises a positive electrode detection module, a negative electrode detection module and a control module; the positive electrode detection module comprises a first resistor, a first voltage dividing resistor and a first switch module; the negative electrode detection module comprises a second resistor, a second voltage dividing resistor and a second switch module; the positive electrode detection module is used for outputting the voltage value between the first voltage dividing resistor to the control module; the negative electrode detection module is used for outputting the voltage value between the second voltage dividing resistor to the control module; and the control module is used for calculating the resistance value of the positive resistor according to the first closed voltage, the second closed voltage and the first open circuit voltage or calculating the resistance value of the negative resistor according to the first closed voltage, the second closed voltage and the second open circuit voltage, thereby improving the measurement precision of the positive resistor or the negative resistor.

Description

Technical Field

[0001] This invention relates to the field of insulation testing technology, and in particular to an insulation testing device. Background Technology

[0002] The power battery is the primary power source for the electric vehicle's power system. This system operates at a high voltage of several hundred volts, with a rated operating current reaching tens of amps or even higher. Due to the complex operating environment of electric vehicles, aging or moisture in the high-voltage cable insulation can degrade the insulation performance between the high-voltage circuit and the vehicle chassis. Under high voltage, the high-voltage side circuit of the electric vehicle will generate extremely high instantaneous currents, threatening the safety of the vehicle and its occupants. Therefore, the insulation performance of an electric vehicle has a crucial impact on vehicle safety, and this insulation performance can be described by the magnitude of its insulation resistance.

[0003] Currently, the detection accuracy of insulation testing devices is not high enough, especially at the two extremes, where the detection accuracy error is relatively large. Summary of the Invention

[0004] This invention provides an insulation detection device to improve the measurement accuracy of positive or negative resistance.

[0005] According to one aspect of the present invention, an insulation detection device is provided for detecting the insulation resistance value of an energy storage system. The energy storage system includes a power source, a positive resistor, and a negative resistor. The positive terminal of the power source is electrically connected to a first end of the positive resistor, the negative terminal of the power source is electrically connected to a second end of the negative resistor, the second end of the positive resistor is electrically connected to the first end of the negative resistor, and the second end of the positive resistor is connected to a reference ground.

[0006] The insulation testing device includes:

[0007] Positive electrode detection module, negative electrode detection module, and control module;

[0008] The positive electrode detection module includes a first resistor, a first voltage divider resistor, and a first switch module, which are connected in series; the negative electrode detection module includes a second resistor, a second voltage divider resistor, and a second switch module, which are connected in series.

[0009] The positive detection module is connected across the positive resistor, and the output of the positive detection module is electrically connected to the first input of the control module, which is used to output the voltage value across the first voltage divider resistor to the control module.

[0010] The negative electrode detection module is connected across the negative resistor, and the output terminal of the negative electrode detection module is electrically connected to the second input terminal of the control module, which is used to output the voltage value across the second voltage divider resistor to the control module.

[0011] The control module is used to calculate the resistance value of the positive resistor based on the first closed voltage, the second closed voltage, and the first open-circuit voltage, or to calculate the resistance value of the negative resistor based on the first closed voltage, the second closed voltage, and the second open-circuit voltage; wherein, the first closed voltage is the voltage value across the first voltage divider resistor when the first switch module and the second switch module are closed simultaneously; the second closed voltage is the voltage value across the second voltage divider resistor when the first switch module and the second switch module are closed simultaneously; the first open-circuit voltage is the voltage value across the first voltage divider resistor when the first switch module is closed and the second switch module is open; and the second open-circuit voltage is the voltage value across the second voltage divider resistor when the first switch module is open and the second switch module is closed.

[0012] Optionally, the control module is also used to determine the resistance value of the calculated positive resistor or the resistance value of the negative resistor based on the comparison result between the first closing voltage and the second closing voltage.

[0013] Optionally, the control module is used to control the second switch module to open and the first switch module to close when the resistance value of the positive resistor is determined to be less than the resistance value of the negative resistor based on the first closing voltage and the second closing voltage, and to obtain the first open-circuit voltage, and to calculate the resistance value of the positive resistor based on the first closing voltage, the second closing voltage and the first open-circuit voltage; or to control the first switch module to open and the second switch module to close when the resistance value of the positive resistor is determined to be greater than the resistance value of the negative resistor based on the first closing voltage and the second closing voltage, and to obtain the second open-circuit voltage, and to calculate the resistance value of the negative resistor based on the first closing voltage, the second closing voltage and the second open-circuit voltage.

[0014] Optionally, the first switch module includes:

[0015] Fourth resistor, seventh resistor, ninth resistor, first transistor, second transistor, first optocoupler, second optocoupler, and ferrite bead;

[0016] The first terminal of the control module is electrically connected to the first terminal of the first transistor and the first terminal of the fourth resistor. The second terminal of the fourth resistor is electrically connected to the second terminal of the first transistor and the first ground terminal. The third terminal of the first transistor is electrically connected to the second terminal of the first optocoupler. The first power supply terminal is electrically connected to the first terminal of the first optocoupler. The second power supply terminal is electrically connected to the fourth terminal of the first optocoupler. The third terminal of the first optocoupler is electrically connected to the first terminal of the second transistor and the first terminal of the ninth resistor.

[0017] The first terminal of the second optocoupler and the first terminal of the seventh resistor are connected to the second power supply terminal. The second terminal of the sixth resistor is electrically connected to the first terminal of the second optocoupler. The second terminal of the seventh resistor is electrically connected to the second terminal of the second optocoupler. The second terminal of the ninth resistor is electrically connected to the second terminal of the second transistor. The second terminal of the second transistor is electrically connected to the second ground terminal. The second terminal of the second transistor is electrically connected to the first terminal of the ferrite bead. The second terminal of the ferrite bead is electrically connected to the reference ground. The third terminal of the second transistor is electrically connected to the second optocoupler. The third terminal of the second optocoupler is electrically connected to the second terminal of the first resistor. The fourth terminal of the second optocoupler is electrically connected to the first terminal of the first voltage divider resistor.

[0018] Optionally, the positive electrode detection module may also include:

[0019] The first filtering and amplification module and the first analog-to-digital conversion module;

[0020] The first terminal of the first switch module is electrically connected to the first terminal of the control module. The second terminal of the first switch module is electrically connected to the second terminal of the first resistor. The first terminal of the first resistor is electrically connected to the positive terminal of the power supply. The third terminal of the first switch module is electrically connected to the first terminal of the first voltage divider resistor. The second terminal of the first voltage divider resistor is electrically connected to the second ground terminal. The first terminal of the first voltage divider resistor is electrically connected to the first terminal of the first filter amplification module. The second terminal of the first filter amplification module is electrically connected to the first terminal of the first analog-to-digital converter module. The second terminal of the first analog-to-digital converter module is electrically connected to the second terminal of the control module. The third terminal of the first analog-to-digital converter module is electrically connected to the third terminal of the control module.

[0021] Optionally, the first filtering and amplification module includes:

[0022] Eleventh resistor, thirteenth resistor, fourteenth resistor, first capacitor, second capacitor, and dual operational amplifier;

[0023] The first terminal of the first voltage divider resistor is electrically connected to the first terminal of the eleventh resistor and the first terminal of the first capacitor. The second terminal of the first capacitor is electrically connected to the first and second terminals of the dual operational amplifier. The second terminal of the eleventh resistor is electrically connected to the third terminal of the dual operational amplifier. The second terminal of the eleventh resistor is electrically connected to the first terminal of the second capacitor. The second terminal of the second capacitor is electrically connected to the fourth terminal and the second ground terminal of the dual operational amplifier.

[0024] The fifth terminal of the dual operational amplifier is electrically connected to the first terminal of the dual operational amplifier; the sixth terminal of the dual operational amplifier is electrically connected to the first terminal of the thirteenth resistor; the second terminal of the thirteenth resistor is electrically connected to the second ground terminal; the seventh terminal of the dual operational amplifier is electrically connected to the first terminal of the fourteenth resistor; the second terminal of the fourteenth resistor is electrically connected to the sixth terminal of the dual operational amplifier; the seventh terminal of the dual operational amplifier is electrically connected to the second ground terminal and the first terminal of the first analog-to-digital converter module; and the eighth terminal of the dual operational amplifier is electrically connected to the second power supply terminal.

[0025] Optionally, the first analog-to-digital conversion module includes:

[0026] Digital-to-analog converter unit and switching unit;

[0027] The first terminal of the digital-to-analog converter is electrically connected to the second terminal of the first filter and amplification module, the second terminal of the digital-to-analog converter is electrically connected to the second terminal of the control module, the third terminal of the digital-to-analog converter is electrically connected to the first terminal of the switching unit, and the second terminal of the switching unit is electrically connected to the third terminal of the control module.

[0028] Optionally, the digital-to-analog conversion unit includes:

[0029] A / D converter, sixth capacitor and seventh capacitor;

[0030] The seventh and eighth terminals of the A / D converter are electrically connected to the second power supply terminal; the fifth and sixth terminals of the A / D converter are electrically connected to the second ground terminal; the fourth terminal of the A / D converter is electrically connected to the first terminal of the sixth capacitor and the first terminal of the seventh capacitor; the fourth terminal of the A / D converter is electrically connected to the second terminal of the fifteenth resistor and the first terminal of the fifth capacitor; the second terminals of the sixth capacitor and the second terminals of the seventh capacitor are electrically connected to the second ground terminal; the third terminal of the A / D converter is electrically connected to the second ground terminal; the second terminal of the A / D converter is electrically connected to the first terminal of the switching unit; and the first, ninth, and tenth terminals of the A / D converter are electrically connected to the second terminal of the control module.

[0031] Optionally, the switching unit includes:

[0032] The sixteenth resistor, the third transistor, and the third optocoupler;

[0033] The third terminal of the control module is electrically connected to the first terminal of the sixteenth resistor and the first terminal of the third transistor. The second terminal of the sixteenth resistor is electrically connected to the second terminal of the third transistor and the first ground terminal. The third terminal of the third transistor is electrically connected to the second terminal of the third optocoupler. The first power supply terminal is electrically connected to the first terminal of the third optocoupler. The second power supply terminal is electrically connected to the first terminal of the nineteenth resistor. The second terminal of the nineteenth resistor is electrically connected to the fourth terminal of the third optocoupler. The third terminal of the third optocoupler is electrically connected to the second ground terminal. The fourth terminal of the third optocoupler is electrically connected to the second terminal of the A / D converter.

[0034] Optionally, the negative electrode detection module also includes:

[0035] Second filtering and amplification module; Second analog-to-digital conversion module;

[0036] The second switching module includes a fourth optocoupler;

[0037] The first terminal of the second switching module is electrically connected to the fourth terminal of the control module. The first terminal of the fourth optocoupler in the second switching module is electrically connected to the second ground terminal. The second terminal of the fourth optocoupler in the second switching module is electrically connected to the first terminal of the second resistor. The second terminal of the second resistor is electrically connected to the first terminal of the second voltage divider resistor. The second terminal of the second voltage divider resistor is electrically connected to the negative terminal of the power supply. The first terminal of the second voltage divider resistor is electrically connected to the first terminal of the second filter amplification module. The second terminal of the second filter amplification module is electrically connected to the first terminal of the second analog-to-digital converter module. The second terminal of the second analog-to-digital converter module is electrically connected to the fifth terminal of the control module.

[0038] In this embodiment of the invention, the positive detection module is connected across the two ends of a positive resistor, and its output terminal is electrically connected to the first input terminal of the control module. The positive detection module outputs the voltage value across the first voltage divider resistor to the control module. The negative detection module is connected across the two ends of a negative resistor, and its output terminal is electrically connected to the second input terminal of the control module. The negative detection module outputs the voltage value across the second voltage divider resistor to the control module. The control module calculates the resistance value of the positive resistor based on the first closed voltage, the second closed voltage, and the first open-circuit voltage, or calculates the resistance value of the negative resistor based on the first closed voltage, the second closed voltage, and the second open-circuit voltage, thereby improving the measurement accuracy of the positive or negative resistor.

[0039] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the structure of an insulation detection device according to an embodiment of the present invention;

[0042] Figure 2 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the structure of another insulation detection device provided according to an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the structure of another insulation detection device provided according to an embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention;

[0046] Figure 6 This is a schematic diagram of the structure of another insulation detection device provided according to an embodiment of the present invention;

[0047] Figure 7 This is a circuit connection diagram of the first switch module of an insulation detection device according to an embodiment of the present invention;

[0048] Figure 8 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention;

[0049] Figure 9 This is a circuit connection diagram of the first filtering and amplification module of an insulation detection device according to an embodiment of the present invention;

[0050] Figure 10 This is a schematic diagram of the structure of another insulation detection device provided according to an embodiment of the present invention;

[0051] Figure 11 This is a schematic diagram of the structure of another insulation detection device provided according to an embodiment of the present invention;

[0052] Figure 12 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention;

[0053] Figure 13 This is a schematic diagram of the structure of the second analog-to-digital conversion module in an insulation detection device according to an embodiment of the present invention. Detailed Implementation

[0054] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0055] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0056] This invention provides an insulation detection device. Figure 1 This is a schematic diagram of an insulation detection device according to an embodiment of the present invention. (Refer to...) Figure 1 The insulation testing device is used to detect the insulation resistance value of the energy storage system. The energy storage system includes a power supply Q, a positive resistor Rp and a negative resistor Rn. The positive terminal of the power supply Q is electrically connected to the first end of the positive resistor Rp, the negative terminal of the power supply Q is electrically connected to the second end of the negative resistor Rn, the second end of the positive resistor Rp is electrically connected to the first end of the negative resistor Rn, and the second end of the positive resistor Rp is connected to the reference ground GND1.

[0057] The insulation testing device includes:

[0058] Positive electrode detection module J1, negative electrode detection module J2, and control module K;

[0059] The positive electrode detection module J1 includes a first resistor Rp1, a first voltage divider resistor Rps, and a first switch module Sp, which are connected in series. The negative electrode detection module J2 includes a second resistor Rn1, a second voltage divider resistor Rns, and a second switch module Sn, which are connected in series.

[0060] The positive detection module J1 is connected across the positive resistor Rp, and the output terminal of the positive detection module Rp is electrically connected to the first input terminal of the control module K, which is used to output the voltage value across the first voltage divider resistor Rps to the control module K.

[0061] The negative electrode detection module J2 is connected across the negative resistor Rn, and the output terminal of the negative electrode detection module J2 is electrically connected to the second input terminal of the control module K, which is used to output the voltage value across the second voltage divider resistor Rns to the control module K.

[0062] The control module K is used to calculate the resistance value of the positive resistor Rp based on the first closed voltage, the second closed voltage, and the first open-circuit voltage, or to calculate the resistance value of the negative resistor Rn based on the first closed voltage, the second closed voltage, and the second open-circuit voltage; wherein, the first closed voltage is the voltage value across the first voltage divider resistor Rps when the first switch module Sp and the second switch module Sn are closed simultaneously; the second closed voltage is the voltage value across the second voltage divider resistor Rns when the first switch module Sp is closed and the second switch module Sn is open; and the second open-circuit voltage is the voltage value across the second voltage divider resistor Rns when the first switch module Sp is open and the second switch module Sn is closed.

[0063] The leakage resistance can be understood as the resistance corresponding to the leakage current flowing through the insulating medium between the power bus and the reference ground GND1 when a DC voltage is applied.

[0064] Specifically, when the battery management system is not working, the first switch module Sp and the second switch module Sn in the insulation detection device are in the open state. At this time, the resistance to ground of the detection circuit in the insulation detection device is much greater than 2MΩ, and at the same time, the voltage to ground of the positive terminal and the voltage to ground of the negative terminal of the power supply Q are lower than the safe voltage of 36V for the human body. This can effectively prevent electric shock and provide good safety protection for the maintenance operation of the battery management system. When the battery management system is working, the insulation detection device is in the working state. For example, the control module K controls the first switch module Sp and the second switch module Sn to close simultaneously, determining the first closing voltage across the first voltage divider resistor Rps and the second closing voltage across the second voltage divider resistor Rns. Then, the control module K compares the first closing voltage with the second closing voltage, and determines the value of the positive resistor Rp or the negative resistor Rn based on the comparison result. To determine the value of the positive resistor Rp, the first switch module Sp must be closed and the second switch module Sn must be open. The first open-circuit voltage across the first voltage divider resistor Rps must be determined at this time, and the value of the positive resistor Rp must be calculated based on the first closed voltage, the second closed voltage, and the first open-circuit voltage. To determine the value of the negative resistor Rn, the first switch module Sp must be open and the second switch module Sn must be closed. The second open-circuit voltage across the second voltage divider resistor Rns must be determined at this time, and the value of the negative resistor Rn must be calculated based on the first closed voltage, the second closed voltage, and the second open-circuit voltage.

[0065] In this embodiment of the invention, the positive detection module J1 is connected to both ends of the positive resistor Rp, and the output terminal of the positive detection module Rp is electrically connected to the first input terminal of the control module K. The positive detection module Rp outputs the voltage value across the first voltage divider resistor Rps to the control module K. The negative detection module J2 is connected to both ends of the negative resistor Rn, and the output terminal of the negative detection module J2 is electrically connected to the second input terminal of the control module K. The negative detection module J2 outputs the voltage value across the second voltage divider resistor Rns to the control module K. The control module K calculates the resistance value of the positive resistor Rp based on the first closed voltage, the second closed voltage, and the first open-circuit voltage, or calculates the resistance value of the negative resistor Rn based on the first closed voltage, the second closed voltage, and the second open-circuit voltage, thereby improving the measurement accuracy of the positive resistor Rp or the negative resistor Rn.

[0066] Optional, see reference Figure 1 The control module K is also used to determine the resistance value of the positive resistor Rp or the resistance value of the negative resistor Rn based on the comparison result between the first closing voltage and the second closing voltage.

[0067] Specifically, based on the comparison results of the first closing voltage and the second closing voltage, the control module K determines whether the resistance value of the positive resistor Rp is greater than the resistance value of the negative resistor Rn, and calculates the resistance value of the negative resistor Rn; conversely, it determines whether the resistance value of the positive resistor Rp is less than the resistance value of the negative resistor Rn, and calculates the resistance value of the positive resistor Rp.

[0068] For example, under the condition that the resistance of the first voltage divider resistor Rps is equal to the resistance of the second voltage divider resistor Rns and the resistance of the first resistor Rp1 is equal to the resistance of the second resistor Rn1, if the first closing voltage is greater than the second closing voltage, it means that when the first switch module Sp and the second switch module Sn are closed simultaneously, the voltage across the first voltage divider resistor Rps is greater than the voltage across the second voltage divider resistor Rns. This indicates that the voltage across the positive resistor Rp is greater than the voltage across the negative resistor Rn, meaning the resistance of the positive resistor Rp is greater than the resistance of the negative resistor Rn. If the detected resistance of the negative resistor Rn meets the insulation resistance testing requirements, then the resistance of the positive resistor Rp... If the insulation resistance test requirements are met, then only the resistance value of the negative resistor Rn needs to be calculated. If the first closing voltage is less than the second closing voltage, it means that when the first switch module Sp and the second switch module Sn are closed simultaneously, the voltage across the first voltage divider resistor Rps is less than the voltage across the second voltage divider resistor Rns. This means that the voltage across the positive resistor Rp is less than the voltage across the negative resistor Rn, and the resistance value of the positive resistor Rp is less than the resistance value of the negative resistor Rn. If the resistance value of the positive resistor Rp obtained by the test meets the insulation resistance test requirements, then the resistance value of the negative resistor Rn must also meet the insulation resistance test requirements. In this case, only the resistance value of the positive resistor Rp needs to be calculated.

[0069] Optional, see reference Figure 1 The control module K is used to control the second switch module Sn to open and the first switch module Sp to close when the resistance value of the positive resistor Rp is determined to be less than the resistance value of the negative resistor Rn based on the first closing voltage and the second closing voltage, and to obtain the first open-circuit voltage, and to calculate the resistance value of the positive resistor Rp based on the first closing voltage, the second closing voltage and the first open-circuit voltage; or to control the first switch module Sp to open and the second switch module Sn to close when the resistance value of the positive resistor Rp is determined to be greater than the resistance value of the negative resistor Rn based on the first closing voltage and the second closing voltage, and to obtain the second open-circuit voltage, and to calculate the resistance value of the negative resistor based on the first closing voltage, the second closing voltage and the second open-circuit voltage.

[0070] Specifically, let the first closed voltage be Up, the second closed voltage be Un, the first open-circuit voltage be Up', the second open-circuit voltage be Un', and the voltage across the power supply Q be SumV.

[0071] Figure 2 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention; as shown. Figure 2 As shown, when the first switch module Sp and the second switch module Sn are closed simultaneously, the first KCL equation obtained is:

[0072] (Up / Rps*Rp1+Up) / Rp+Up / Rps=(Un / Rns*Rn1+Un) / Rn+Un / Rns;

[0073] (1) Figure 3 This is a schematic diagram of the structure of another insulation detection device provided according to an embodiment of the present invention, as shown below. Figure 3 As shown, when the resistance of the positive resistor Rp is determined to be less than the resistance of the negative resistor Rn based on the first closing voltage Up and the second closing voltage Un, the second switch module Sn is controlled to open, the first switch module Sp is controlled to close, and the first open-circuit voltage Up' is obtained. If the first open-circuit voltage Up' is not zero, the second KCL equation obtained at this time is:

[0074] (Up' / Rps*Rp1+Up') / Rp+Up' / Rps=(SumV-Up' / Rps*Rp1-Up') / Rn;

[0075] The resistance value of the positive resistor is calculated using the first and second KCL equations:

[0076] Rp=[(Rps+Rp1)Up*SumV-(Rps*Rp1+Rp1*Rp1+Rps*Rps+Rps*Rp1)Up*Up' / 100Rps-(Rns*Rp1+Rn1*Rp1+Rns*Rps+Rps*Rn1)Un*Up' / 100Rns] / [(Rps+Rp1)*Up*Up' / 100Rps+Un*Up' / 100-Un*Up'*Rps / 100Rns+Un*Up'*Rn1 / 100Rns-Un*Up'*Rp1 / 100Rns+Rps*Un*SumV / Rns-Up*SumV].

[0077] Figure 4 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention, as shown below. Figure 4 As shown, if the first open-circuit voltage Up' is zero, then the negative resistance Rn is infinite or the negative resistance Rn is open-circuited. In this case, the third KCL equation is obtained as follows:

[0078] (Up / Rps*Rp1+Up) / Rp+Up / Rps=Un / Rns;

[0079] The resistance value of the positive resistor is calculated using the first and third KCL equations:

[0080] Rp=(Rps*Rns+Rns*Rp1)Up / (Un*Rps-Up*Rns).

[0081] (2) Figure 5 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention, such as... Figure 5 As shown, when the resistance of the positive resistor Rp is determined to be greater than the resistance of the negative resistor Rn based on the first closing voltage Up and the second closing voltage Un, the first switch module Sp is opened, the second switch module Sn is closed, and the second open-circuit voltage Un' is obtained. If the second open-circuit voltage Un' is not zero, the fourth KCL equation obtained at this time is:

[0082] (Un' / Rns*Rn1+Un') / Rn+Un' / Rns=(SumV-Un' / Rns*Rn1-Un') / Rp;

[0083] The resistance value of the negative resistor Rn is calculated based on the first and fourth KCL equations:

[0084] Rn=[(Rps+Rp1)Un*SumV-(Rps*Rp1+Rp1*Rp1+Rps*Rps+Rps*Rp1)Un*Un' / 100Rps-(Rns*Rp1+Rn1*Rp1+Rns*Rps+Rps*Rn1)Up*Un' / 100Rns] / [(Rps+Rp1)Un*Un' / 100Rps+Up*Un' / 100-Up*Un'*Rps / 100Rns+Up*Un'*Rn1 / 100Rns-Up*Un'*Rp1 / 100Rns+Rps*Up*SumV / Rns-Un*SumV];

[0085] Figure 6 This is a schematic diagram of the structure of another insulation detection device provided according to an embodiment of the present invention, as shown below. Figure 6 As shown, if the second open-circuit voltage Un' is zero, then the positive resistance Rp is infinite or the positive resistance Rp is open-circuited. In this case, the fifth KCL equation is obtained as follows:

[0086] (Un / Rns*Rn1+Un) / Rn+Un / Rns=Up / Rps;

[0087] The resistance value of the negative resistor is calculated using the first and fifth KCL equations:

[0088] Rn=(Rps*Rns+Rps*Rn1)Un / (Up*Rns-Un*Rps).

[0089] Figure 7 This is a circuit connection diagram of the first switch module of an insulation detection device according to an embodiment of the present invention. Optionally, refer to... Figure 7 The first switch module Sp includes:

[0090] The components are: third resistor R1, fourth resistor R2, fifth resistor R3, sixth resistor R4, seventh resistor R5, eighth resistor R6, ninth resistor R7, first transistor Q1, second transistor Q2, first optocoupler U1, second optocoupler U2, and ferrite bead FB.

[0091] The first terminal of the control module is electrically connected to the first terminal of the third resistor R1 and the first terminal of the fourth resistor R2. The second terminal of the third resistor R1 is electrically connected to the first terminal of the first transistor Q1. The second terminal of the fourth resistor R2 is electrically connected to the second terminal of the first transistor Q1 and the first ground terminal GND. The third terminal of the first transistor Q1 is electrically connected to the second terminal of the first optocoupler U1. The first power supply terminal VCC is electrically connected to the first terminal of the fifth resistor R3. The second terminal of the fifth resistor R3 is electrically connected to the first terminal of the first optocoupler U1. The second power supply terminal VCC1 is electrically connected to the fourth terminal of the first optocoupler U1. The third terminal of the first optocoupler U1 is electrically connected to the first terminal of the eighth resistor R6 and the first terminal of the ninth resistor R7.

[0092] The first terminals of the sixth resistor R4 and the seventh resistor R5 are connected to the second power supply terminal VCC1. The second terminal of the sixth resistor R4 is electrically connected to the first terminal of the second optocoupler U2. The second terminal of the seventh resistor R5 is electrically connected to the second terminal of the second optocoupler U2. The second terminal of the eighth resistor R6 is electrically connected to the first terminal of the second transistor Q2. The second terminal of the ninth resistor R7 is electrically connected to the second terminal of the second transistor Q2. The second terminal of the second transistor Q2 is electrically connected to the second ground terminal GND2. The second terminal of the second transistor Q2 is electrically connected to the first terminal of the ferrite bead FB. The second terminal of the ferrite bead FB is electrically connected to the reference ground GND1. The third terminal of the second transistor Q2 is electrically connected to the second optocoupler U2. The third terminal of the second optocoupler U2 is electrically connected to the second terminal of the first resistor Rp1. The fourth terminal of the second optocoupler U2 is electrically connected to the first terminal of the first voltage divider resistor Rps.

[0093] Specifically, when the control module determines the value of the positive resistor, it needs to send a high-level signal to the first switch module Sp. After receiving the high-level signal from the control module, the first switch module Sp is energized and turns on the first transistor Q1, which connects the first power supply terminal VCC, the fifth resistor R3, the LED in the first optocoupler U1, the first transistor Q1, and the first ground terminal GND, forming a closed loop. At this time, the LED in the first optocoupler U1 is energized and turns on, which connects the second power supply terminal VCC1, the first optocoupler U1, the ninth resistor R7, and the second ground terminal GND2, forming a closed loop. The second transistor Q2 receives the high-level signal and turns on, which connects the second power supply terminal VCC1, the sixth resistor R4, the LED in the second optocoupler U2, the second transistor Q2, and the second ground terminal GND2, forming a closed loop. At this time, the LED in the second optocoupler U2 is energized and turns on, which connects the first resistor Rp1 and the first voltage divider resistor Rps in series, resulting in the first switch module Sp being closed and the positive detection module being turned on.

[0094] Figure 8 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention. Optionally, refer to... Figure 8 The positive electrode detection module also includes:

[0095] First filtering and amplification module 10 and first analog-to-digital conversion module 20;

[0096] The first terminal of the first switch module Sp is electrically connected to the first terminal of the control module K. The second terminal of the first switch module Sp is electrically connected to the second terminal of the first resistor Rp1. The first terminal of the first resistor Rp1 is electrically connected to the positive terminal of the power supply. The third terminal of the first switch module Sp is electrically connected to the first terminal of the first voltage divider resistor Rps. The second terminal of the first voltage divider resistor Rps is electrically connected to the second ground terminal GND2. The first terminal of the first voltage divider resistor Rps is electrically connected to the first terminal of the first filter amplifier module 10. The second terminal of the first filter amplifier module 10 is electrically connected to the first terminal of the first analog-to-digital converter module 20. The second terminal of the first analog-to-digital converter module 20 is electrically connected to the second terminal of the control module K. The third terminal of the first analog-to-digital converter module 20 is electrically connected to the third terminal of the control module K.

[0097] The first resistor Rp1 can be formed by connecting multiple resistors in series. For example, the first resistor Rp1 can be formed by connecting four resistors with the same resistance value in series.

[0098] Specifically, when determining the resistance value of the positive resistor, the control module K sends a high-level signal to the first switch module Sp. Upon receiving this signal, the first switch module Sp connects the positive terminal of the power supply, the first resistor Rp1, the first voltage divider resistor Rps, and the second ground terminal GND2, forming a closed loop. Simultaneously, it sends an "Analog-to-Digital Converter Module Open" signal to the first analog-to-digital converter module 20, controlling it to start operation. The closing of the first switch module Sp allows the voltage across the first voltage divider resistor Rps to be transmitted to the first filter and amplify module 10. The first filter and amplify module 10 filters and amplifies the analog signal of the voltage across the first voltage divider resistor Rps, then transmits the processed analog signal to the first analog-to-digital converter module 20. The first filter and amplify module 20 converts the analog signal of the voltage across the first voltage divider resistor Rps into a digital signal, which is then transmitted to the control module K for calculation, ultimately calculating the resistance value of the positive resistor. Because the analog signal is processed by the first filter and amplify module 10, interference signals are effectively removed, resulting in a more accurate resistance value calculated by the control module K.

[0099] Figure 9 This is a circuit connection diagram of the first filtering and amplification module of an insulation detection device according to an embodiment of the present invention. Optionally, refer to... Figure 9 The first filtering and amplification module includes:

[0100] The tenth resistor R8, the eleventh resistor R9, the twelfth resistor R10, the thirteenth resistor R11, the fourteenth resistor R12, the fifteenth resistor R13, the first capacitor C1, the second capacitor C2, the third capacitor C3, the fourth capacitor C4, the fifth capacitor C5, and the dual operational amplifier U3;

[0101] The first terminal of the first voltage divider resistor is electrically connected to the first terminal of the tenth resistor R8. The second terminal of the tenth resistor R8 is electrically connected to the first terminal of the eleventh resistor R9 and the first terminal of the first capacitor C1. The second terminal of the first capacitor C1 is electrically connected to the first terminal 1 and the second terminal 2 of the dual operational amplifier U3. The second terminal of the eleventh resistor R9 is electrically connected to the third terminal 3 of the dual operational amplifier U3. The second terminal 2 of the eleventh resistor R9 is electrically connected to the first terminal of the second capacitor C2. The second terminal of the second capacitor C2 is electrically connected to the fourth terminal and the second ground terminal GND2 of the dual operational amplifier U3.

[0102] The fifth terminal 5 of the dual operational amplifier U3 is electrically connected to the first terminal of the twelfth resistor R10; the sixth terminal 6 of the dual operational amplifier U3 is electrically connected to the first terminal of the thirteenth resistor R11; the second terminal of the twelfth resistor R10 is electrically connected to the first terminal 1 of the dual operational amplifier U3; the second terminal of the thirteenth resistor R11 is electrically connected to the second ground terminal GND2; the seventh terminal of the dual operational amplifier U3 is electrically connected to the first terminal of the fourteenth resistor R12 and the first terminal of the fifteenth resistor R13; the second terminal of the fourteenth resistor R12 is electrically connected to the sixth terminal 6 of the dual operational amplifier U3; the second terminal of the fifteenth resistor R13 is electrically connected to the first terminal of the fifth capacitor C5 and the first terminal of the first analog-to-digital converter module; and the second terminal of the fifth capacitor C5 is electrically connected to the second ground terminal GND2.

[0103] The eighth terminal 8 of the dual operational amplifier U3 is electrically connected to the second power supply terminal VCC1. The first terminal of the third capacitor C3 and the first terminal of the fourth capacitor C4 are electrically connected to the second power supply terminal VCC1. The second terminal of the third capacitor C3 and the second terminal of the fourth capacitor C4 are electrically connected to the second ground terminal GND2.

[0104] Specifically, after the voltage signal across the first voltage divider resistor Rps is input to the first filter and amplification module, the voltage signal passes through the tenth resistor R8 and the eleventh resistor R9 and enters the third terminal 3 of the dual operational amplifier U3. After filtering, the voltage signal is converted into a voltage signal without interference. The voltage signal without interference is input from the first terminal 1 of the dual operational amplifier U3 through the twelfth resistor R10 to the fifth terminal 5 of the dual operational amplifier U3. After amplification, the voltage signal without interference is input to the first analog-to-digital converter module through the fifteenth resistor R13.

[0105] Figure 10 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention. Optionally, refer to... Figure 10 The first analog-to-digital conversion module 20 includes:

[0106] Digital-to-analog converter unit 21 and switching unit 22;

[0107] The first end of the digital-to-analog converter 21 is electrically connected to the second end of the first filter and amplification module 10, the second end of the digital-to-analog converter 21 is electrically connected to the second end of the control module K, the third end of the digital-to-analog converter 21 is electrically connected to the first end of the switch unit 22, and the second end of the switch unit 22 is electrically connected to the third end of the control module K.

[0108] Specifically, while sending a high-level signal to the first switch module Sp, the control module K sends an analog-to-digital converter module open signal to the first analog-to-digital converter module 20, controlling the switch unit 22 to close, so that the first analog-to-digital converter unit 21 starts working, converting the analog signal input from the first filter amplification module 10 into a digital signal, and transmitting it to the control module K for calculation and processing, and finally calculating the resistance value of the positive resistor.

[0109] Figure 11 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention. Optionally, refer to... Figure 11 The digital-to-analog conversion unit 21 includes:

[0110] A / D converter U4, sixth capacitor C6 and seventh capacitor C7;

[0111] The seventh terminal 7 and the eighth terminal 8 of the A / D converter U4 are electrically connected to the second power supply terminal VCC1. The fifth terminal 5 and the sixth terminal 6 of the A / D converter U4 are electrically connected to the second ground terminal GND2. The fourth terminal 4 of the A / D converter U4 is electrically connected to the first terminal of the sixth capacitor C6 and the first terminal of the seventh capacitor C7. The fourth terminal 4 of the A / D converter U4 is electrically connected to the second terminal of the fifteenth resistor and the first terminal of the fifth capacitor. The second terminals of the sixth capacitor C6 and the seventh capacitor C7 are electrically connected to the second ground terminal GND2. The third terminal 3 of the A / D converter U4 is electrically connected to the second ground terminal GND2. The second terminal 2 of the A / D converter U4 is electrically connected to the first terminal of the switching unit 22. The first terminal 1, the ninth terminal 9, and the tenth terminal 10 of the A / D converter U4 are electrically connected to the second terminal of the control module.

[0112] Specifically, when the switch unit 22 is closed, the second terminal 2 of the A / D converter U4 will receive a high-level signal, which will trigger the A / D converter U4 to start working. The analog signal processed by the first filtering and amplification module is input through the fourth terminal of the A / D converter U4. After analog-to-digital conversion in the A / D converter U4, it is transmitted to the control module through the first terminal 1, the ninth terminal 9 and the tenth terminal 10 of the A / D converter U4 for calculation and processing, and finally the resistance value of the positive resistor is calculated.

[0113] Optional, continue to refer to Figure 11 The switching unit 22 includes:

[0114] The sixteenth resistor R14, the seventeenth resistor R15, the eighteenth resistor R16, the nineteenth resistor R17, the third transistor Q3, and the third optocoupler U5;

[0115] The third terminal of the control module is electrically connected to the first terminal of the sixteenth resistor R14 and the first terminal of the seventeenth resistor R15. The second terminal of the seventeenth resistor R15 is electrically connected to the first terminal of the third transistor Q3. The second terminal of the sixteenth resistor R14 is electrically connected to the second terminal of the third transistor Q3 and the first ground terminal GND. The third terminal of the third transistor Q3 is electrically connected to the second terminal of the third optocoupler U5. The first power supply terminal VCC is electrically connected to the first terminal of the eighteenth resistor R16. The second terminal of the eighteenth resistor R16 is electrically connected to the first terminal of the third optocoupler U5. The second power supply terminal VCC1 is electrically connected to the first terminal of the nineteenth resistor R17. The second terminal of the nineteenth resistor R17 is electrically connected to the fourth terminal of the third optocoupler U5. The third terminal of the third optocoupler U5 is electrically connected to the second ground terminal GND2. The fourth terminal of the third optocoupler U5 is electrically connected to the second terminal 2 of the A / D converter U4.

[0116] Specifically, while the control module sends a high-level signal to the first switch module, it also sends an analog-to-digital converter module open signal to the switch unit 22. After receiving the analog-to-digital converter module open signal, the switch unit 22 energizes and turns on the third transistor Q3, which in turn turns on the first power supply terminal VCC, the eighteenth resistor R16, the light-emitting diode in the third optocoupler U5, the third transistor Q3, and the first ground terminal GND, forming a closed loop. At this time, the light-emitting diode in the third optocoupler U5 is energized and illuminates, which turns on the second power supply terminal VCC1, the third optocoupler U5, the nineteenth resistor R17, and the second ground terminal GND2, forming a closed loop, thereby triggering the start-up of the A / D converter U4.

[0117] Figure 12 This is a schematic diagram of another insulation detection device provided according to an embodiment of the present invention. Optionally, refer to... Figure 12 The negative electrode detection module also includes:

[0118] Second filter amplification module 100 and second analog-to-digital conversion module 200;

[0119] The second switching module Sn includes a fourth optocoupler U6;

[0120] The first terminal of the second switching module Sn is electrically connected to the fourth terminal of the control module K. The first terminal of the fourth optocoupler U6 in the second switching module Sn is electrically connected to the second ground terminal GND2. The second terminal of the fourth optocoupler U6 in the second switching module Sn is electrically connected to the first terminal of the second resistor Rn1. The second terminal of the second resistor Rn1 is electrically connected to the first terminal of the second voltage divider resistor Rns. The second terminal of the second voltage divider resistor Rns is electrically connected to the negative terminal O of the power supply. The first terminal of the second voltage divider resistor Rns is electrically connected to the first terminal of the second filter amplification module 100. The second terminal of the second filter amplification module 100 is electrically connected to the first terminal of the second analog-to-digital conversion module 200. The second terminal of the second analog-to-digital conversion module 200 is electrically connected to the fifth terminal of the control module K.

[0121] The second resistor Rn1 can be formed by connecting multiple resistors in series. For example, the second resistor Rn1 can be formed by connecting four resistors with the same resistance value in series. The circuit of the second switch module Sn is the same as that of the first switch module.

[0122] Specifically, when determining the resistance value of the negative resistor, the control module K sends a high-level signal to the first switching module Sn. Upon receiving this high-level signal, the first switching module Sn connects the negative terminal O of the power supply, the second resistor Rn1, the second voltage divider resistor Rns, and the second ground terminal GND2, forming a closed loop. The closure of the first switching module Sn causes the voltage across the second voltage divider resistor Rns to be transmitted to the second filtering and amplifying module 100. The second filtering and amplifying module 100 filters and amplifies the analog signal of the voltage across the second voltage divider resistor Rns, then transmits the processed analog signal to the second analog-to-digital converter module 200. This module converts the analog signal of the voltage across the second voltage divider resistor Rns into a digital signal, which is then transmitted to the control module K for calculation, ultimately determining the resistance value of the negative resistor. Because the analog signal is processed by the first filtering and amplifying module 100, interference signals in the analog signal are effectively removed, making the resistance value calculated by the control module K more accurate.

[0123] For example, Figure 13 This is a schematic diagram of the structure of the second analog-to-digital conversion module in an insulation detection device according to an embodiment of the present invention. (Refer to...) Figure 13The processed analog signal is transmitted to the second analog-to-digital converter module through pin a, which converts the analog signal of the voltage across the second voltage divider resistor into a digital signal. The digital signal processed by the second analog-to-digital converter module is then transmitted to the control module through pin b for calculation and processing, and finally the resistance value of the negative resistor is calculated.

[0124] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0125] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An insulation detection device for detecting the insulation resistance value of an energy storage system, the energy storage system comprising a power source, a positive resistor, and a negative resistor, wherein the power source, the positive resistor, and the negative resistor are connected in series, and a first node is provided between the positive resistor and the negative resistor, and the first node is connected to a reference ground; Its features are, The insulation testing device includes: Positive electrode detection module, negative electrode detection module, and control module; The positive electrode detection module includes a first resistor, a first voltage divider resistor, and a first switch module, wherein the first resistor, the first voltage divider resistor, and the first switch module are connected in series; the negative electrode detection module includes a second resistor, a second voltage divider resistor, and a second switch module, wherein the second resistor, the second voltage divider resistor, and the second switch module are connected in series. The positive detection module is connected across the positive resistor, and the positive detection module is used to output the voltage value across the first voltage divider resistor to the control module. The negative electrode detection module is connected across the negative resistor, and the negative electrode detection module is used to output the voltage value across the second voltage divider resistor to the control module. The control module is used to calculate the resistance value of the positive resistor based on the first closing voltage, the second closing voltage, and the first open-circuit voltage, or to calculate the resistance value of the negative resistor based on the first closing voltage, the second closing voltage, and the second open-circuit voltage; wherein, the first closing voltage is the voltage value across the first voltage divider resistor when the first switch module and the second switch module are closed simultaneously; the second closing voltage is the voltage value across the second voltage divider resistor when the first switch module and the second switch module are closed simultaneously; the first open-circuit voltage is the voltage value across the first voltage divider resistor when the first switch module is closed and the second switch module is open; and the second open-circuit voltage is the voltage value across the second voltage divider resistor when the first switch module is open and the second switch module is closed. When the first switch module Sp and the second switch module Sn are closed simultaneously, the first KCL equation obtained is: (Up / Rps*Rp1+Up) / Rp+Up / Rps=(Un / Rns*Rn1+Un) / Rn+Un / Rns; The second switch module Sn is opened, the first switch module Sp is closed, and the first open-circuit voltage Up' is obtained. If the first open-circuit voltage Up' is not zero, the second KCL equation is obtained as: (Up' / Rps*Rp1+Up') / Rp+Up' / Rps=(SumV-Up' / Rps*Rp1-Up') / Rn; the resistance value of the positive resistor Rp is calculated based on the first KCL equation and the second KCL equation. If the first open-circuit voltage Up' is zero, then the negative resistance Rn is infinite or the negative resistance Rn is open-circuited. In this case, the third KCL equation is obtained as: (Up / Rps*Rp1+Up) / Rp+Up / Rps=Un / Rns; the resistance value of the positive resistance Rp is calculated based on the first KCL equation and the third KCL equation. The first switch module Sp is opened, the second switch module Sn is closed, and the second open-circuit voltage Un' is obtained. If the second open-circuit voltage Un' is not zero, the fourth KCL equation obtained is: (Un' / Rns*Rn1+Un') / Rn+Un' / Rns=(SumV-Un' / Rns*Rn1-Un') / Rp; the resistance value of the negative resistor Rn is calculated according to the first KCL equation and the fourth KCL equation. If the second open-circuit voltage Un' is zero, then the positive resistance Rp is infinite or the positive resistance Rp is open-circuited. In this case, the fifth KCL equation is obtained as: (Un / Rns*Rn1+Un) / Rn+Un / Rns=Up / Rps; the resistance value of the negative resistance Rn is calculated based on the first KCL equation and the fifth KCL equation. Where Up is the first closed-circuit voltage, Un is the second closed-circuit voltage, Up' is the first open-circuit voltage, Un' is the second open-circuit voltage, SumV is the voltage across power supply Q, Rps is the first voltage divider resistor, Rp1 is the first resistor, Rp is the positive resistor, Rns is the second voltage divider resistor, Rn1 is the second resistor, and Rn is the negative resistor.

2. The insulation testing device according to claim 1, characterized in that, The control module is also used to determine the resistance value of the positive resistor or the resistance value of the negative resistor based on the comparison result between the first closing voltage and the second closing voltage.

3. The insulation testing device according to claim 2, characterized in that, The control module is used to control the second switch module to open and the first switch module to close when it is determined from the first closing voltage and the second closing voltage that the resistance value of the positive resistor is less than the resistance value of the negative resistor, and to obtain the first open circuit voltage, and to calculate the resistance value of the positive resistor based on the first closing voltage, the second closing voltage and the first open circuit voltage; Alternatively, when it is determined that the resistance value of the positive resistor is greater than the resistance value of the negative resistor based on the first closing voltage and the second closing voltage, the first switch module is controlled to open, the second switch module is controlled to close, the second open-circuit voltage is obtained, and the resistance value of the negative resistor is calculated based on the first closing voltage, the second closing voltage, and the second open-circuit voltage.

4. The insulation testing device according to claim 1, characterized in that, The first switch module includes: Fourth resistor, seventh resistor, ninth resistor, first transistor, second transistor, first optocoupler, second optocoupler, and ferrite bead; The first terminal of the control module is electrically connected to the gate terminal of the first transistor and the first terminal of the fourth resistor. The second terminal of the fourth resistor is electrically connected to the source terminal and the first ground terminal of the first transistor. The drain terminal of the first transistor is electrically connected to the cathode terminal of the light-emitting diode in the first optocoupler. The first power supply terminal is electrically connected to the anode terminal of the light-emitting diode in the first optocoupler. The second power supply terminal is electrically connected to the collector terminal of the phototransistor in the first optocoupler. The emitter terminal of the phototransistor in the first optocoupler is electrically connected to the gate terminal of the second transistor and the first terminal of the ninth resistor. In the second optocoupler, the anode of the LED and the first terminal of the seventh resistor are connected to the second power supply terminal. The second terminal of the seventh resistor is electrically connected to the cathode of the LED in the second optocoupler. The second terminal of the ninth resistor is electrically connected to the source terminal of the second transistor. The source terminal of the second transistor is electrically connected to the second ground terminal. The source terminal of the second transistor is electrically connected to the first terminal of the ferrite bead. The second terminal of the ferrite bead is electrically connected to the reference ground. The drain terminal of the second transistor is electrically connected to the cathode of the LED in the second optocoupler. The positive photosensitive terminal of the photosensitive receiving array in the second optocoupler is electrically connected to the second terminal of the first resistor. The negative photosensitive terminal of the photosensitive receiving array in the second optocoupler is electrically connected to the first terminal of the first voltage divider resistor. The first terminal of the first resistor is electrically connected to the positive terminal of the power supply. The second terminal of the first voltage divider resistor is electrically connected to the second ground terminal.

5. The insulation testing device according to claim 4, characterized in that, The positive electrode detection module also includes: The first filtering and amplification module and the first analog-to-digital conversion module; In the first switching module, the gate terminal of the first transistor is electrically connected to the first terminal of the control module; the photosensitive positive terminal of the second optocoupler in the first switching module is electrically connected to the second terminal of the first resistor; the first terminal of the first resistor is electrically connected to the positive terminal of the power supply; the photosensitive negative terminal of the second optocoupler in the first switching module is electrically connected to the first terminal of the first voltage divider resistor; the second terminal of the first voltage divider resistor is electrically connected to the second ground terminal; the first terminal of the first voltage divider resistor is electrically connected to the first terminal of the first filter amplification module; the second terminal of the first filter amplification module is electrically connected to the first terminal of the first analog-to-digital converter module; the second terminal of the first analog-to-digital converter module is electrically connected to the second terminal of the control module; and the third terminal of the first analog-to-digital converter module is electrically connected to the third terminal of the control module.

6. The insulation testing device according to claim 5, characterized in that, The first filtering and amplification module includes: Eleventh resistor, thirteenth resistor, fourteenth resistor, first capacitor, second capacitor, and dual operational amplifier; The first end of the first voltage divider resistor is electrically connected to the first end of the eleventh resistor and the first end of the first capacitor. The second end of the first capacitor is electrically connected to the first and second ends of the dual operational amplifier. The second end of the eleventh resistor is electrically connected to the third end of the dual operational amplifier. The second end of the eleventh resistor is electrically connected to the first end of the second capacitor. The second end of the second capacitor is electrically connected to the fourth end of the dual operational amplifier and the second ground terminal. The fifth terminal of the dual operational amplifier is electrically connected to the first terminal of the dual operational amplifier; the sixth terminal of the dual operational amplifier is electrically connected to the first terminal of the thirteenth resistor; the second terminal of the thirteenth resistor is electrically connected to the second ground terminal; the seventh terminal of the dual operational amplifier is electrically connected to the first terminal of the fourteenth resistor; the second terminal of the fourteenth resistor is electrically connected to the sixth terminal of the dual operational amplifier; the seventh terminal of the dual operational amplifier is electrically connected to the second ground terminal and the first terminal of the first analog-to-digital conversion module; and the eighth terminal of the dual operational amplifier is electrically connected to the second power supply terminal.

7. The insulation testing device according to claim 5, characterized in that, The first analog-to-digital conversion module includes: Digital-to-analog converter unit and switching unit; The first terminal of the digital-to-analog converter is electrically connected to the second terminal of the first filter amplification module, the second terminal of the digital-to-analog converter is electrically connected to the second terminal of the control module, the third terminal of the digital-to-analog converter is electrically connected to the first terminal of the switching unit, and the second terminal of the switching unit is electrically connected to the third terminal of the control module.

8. The insulation testing device according to claim 7, characterized in that, The digital-to-analog conversion unit includes: A / D converter, sixth capacitor and seventh capacitor; The seventh and eighth terminals of the A / D converter are electrically connected to the second power supply terminal; the fifth and sixth terminals of the A / D converter are electrically connected to the second ground terminal; the fourth terminal of the A / D converter is electrically connected to the first terminal of the sixth capacitor and the first terminal of the seventh capacitor; the fourth terminal of the A / D converter is electrically connected to the second terminal of the fifteenth resistor and the first terminal of the fifth capacitor; the second terminals of the sixth capacitor and the second terminals of the seventh capacitor are electrically connected to the second ground terminal; the third terminal of the A / D converter is electrically connected to the second ground terminal; the second terminal of the A / D converter is electrically connected to the first terminal of the switching unit; and the first, ninth, and tenth terminals of the A / D converter are electrically connected to the second terminal of the control module.

9. The insulation testing device according to claim 7, characterized in that, The switching unit includes: The sixteenth resistor, the third transistor, and the third optocoupler; The third terminal of the control module is electrically connected to the first terminal of the sixteenth resistor and the gate terminal of the third transistor. The second terminal of the sixteenth resistor is electrically connected to the source terminal and the first ground terminal of the third transistor. The drain terminal of the third transistor is electrically connected to the cathode terminal of the light-emitting diode in the third optocoupler. The first power supply terminal is electrically connected to the anode terminal of the light-emitting diode in the third optocoupler. The second power supply terminal is electrically connected to the collector terminal of the phototransistor in the third optocoupler. The emitter terminal of the phototransistor in the third optocoupler is electrically connected to the second ground terminal. The collector terminal of the phototransistor in the third optocoupler is electrically connected to the second terminal of the A / D converter.

10. The insulation testing device according to claim 4, characterized in that, The negative electrode detection module also includes: Second filtering and amplification module; Second analog-to-digital conversion module; The second switching module includes a fourth optocoupler; The gate terminal of the fourth transistor in the second switching module is electrically connected to the fourth terminal of the control module. The negative photosensitive terminal of the photosensitive receiving array in the fourth optocoupler in the second switching module is electrically connected to the second ground terminal. The positive photosensitive terminal of the photosensitive receiving array in the fourth optocoupler in the second switching module is electrically connected to the first terminal of the second resistor. The second terminal of the second resistor is electrically connected to the first terminal of the second voltage divider resistor. The second terminal of the second voltage divider resistor is electrically connected to the negative terminal of the power supply. The first terminal of the second voltage divider resistor is electrically connected to the first terminal of the second filter amplification module. The second terminal of the second filter amplification module is electrically connected to the first terminal of the second analog-to-digital conversion module. The second terminal of the second analog-to-digital conversion module is electrically connected to the fifth terminal of the control module. The second switch module has the same circuit as the first switch module, and the fourth transistor corresponds to the first transistor in the first switch module.

Images