Insulation detection circuit and detection device

Abstract

An insulation detection circuit and a detection device are characterized in that the insulation detection circuit comprises a signal generation module which is electrically connected with a power supply; the battery module is electrically connected with the signal generation module; the sampling module comprises an acquisition end, and the acquisition end is electrically connected with the signal generation module and the battery module; the processing module is electrically connected with the signal generation module and the sampling module, and the processing module is used for obtaining the resistance values of the first insulation resistance of the to-be-detected battery and the second insulation resistance of the to-be-detected battery according to the voltage data collected by the sampling module; resistance values of the first insulation resistor and the second insulation resistor are used for judging insulation failure of the battery module. According to the utility model, through mutual cooperation of the signal generation module, the battery module, the sampling module and the processing module, the resistance value of the insulation resistor can be accurately measured, insulation false alarm and missing alarm are avoided, and the circuit safety is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and more specifically to a battery insulation detection circuit and a detection device. Background Art

[0002] During operation, electrical equipment may experience various faults and abnormal operation due to external influences such as impact pressure, moisture, foreign matter intrusion, or internal material defects, aging, wear, heat, insulation damage, and misoperation during operation. In addition, electronic circuits can be easily damaged by overvoltage, overcurrent, surge, etc.

[0003] With the development of technology, electronic circuit products are becoming increasingly diversified and complex, so circuit protection has become particularly important. Circuit safety is an important factor in ensuring that there are no safety hazards during circuit operation. A safe circuit can effectively prevent circuit accidents and equipment damage, protect the personal safety of users; it can also improve the reliability and stability of the system and extend the service life of the equipment. A battery is responsible for storing and providing electrical energy. With the rapid development of power energy storage systems, energy storage battery systems contain batteries, and there is a risk of battery leakage and insulation damage at the positive and negative electrodes, which causes the system to have excessive leakage current and create risks. Utility Model Content

[0004] The present application is proposed to solve the above-mentioned problems. According to one aspect of the present application, an insulation detection circuit is provided, which includes: a signal generating module, which is electrically connected to a power supply and used to generate a positive pulse voltage signal and a negative pulse voltage signal; a battery module, which includes a battery to be detected, a first insulation resistor and a second insulation resistor, and is electrically connected to the signal generating module; a sampling module, which includes an acquisition end, which is electrically connected to the signal generating module and the battery module, and is used to acquire the positive pulse voltage signal and the negative pulse voltage signal and the voltage of the battery module; a processing module, which is electrically connected to the signal generating module and the sampling module, and is used to obtain the resistance values ​​of the first insulation resistor of the battery to be detected and the second insulation resistor of the battery to be detected according to the voltage data collected by the sampling module, and the resistance values ​​of the first insulation resistor and the second insulation resistor are used to determine whether the battery module insulation has failed.

[0005] As a preferred solution of the present invention, when the resistance value of the first insulation resistor or the resistance value of the second insulation resistor is less than a first threshold value, the insulation of the battery module fails.

[0006] As a preferred solution of the utility model, one end of the first insulation resistor is electrically connected to the positive electrode of the battery to be tested, and the other end of the first insulation resistor is grounded; one end of the second insulation resistor is electrically connected to the negative electrode of the battery to be tested, and the other end of the second insulation resistor is grounded.

[0007] As a preferred solution of the utility model, the battery module also includes a first resistor and a second resistor, one end of the first resistor is electrically connected to the positive electrode of the battery to be detected and one end of the first insulation resistor, and one end of the second resistor is electrically connected to the negative electrode of the battery to be detected and one end of the second insulation resistor; a third resistor, one end of the third resistor is grounded, and the other end of the third resistor is electrically connected to the common end of the first resistor and the second resistor.

[0008] As a preferred solution of the utility model, the signal generating module inputs a positive pulse voltage signal and a negative pulse voltage signal between the third resistor and the ground terminal. The positive pulse voltage signal and the negative pulse voltage signal are two DC pulse voltage signals with equal amplitudes and a phase difference of 180°.

[0009] As a preferred solution of the utility model, the sampling module includes a first sampling module, the collection end of the first sampling module is electrically connected to the signal generating module, and the first sampling module is used to collect the voltage signal of the signal generating circuit; a second sampling module, the collection end of the second sampling module is electrically connected to the common end of the first resistor and the second resistor; a third sampling module, the collection end of the third sampling module is arranged on a branch between the positive electrode of the battery to be detected and the common end of the first resistor and the first insulation resistor; a fourth sampling module, the collection end of the fourth sampling module is arranged on a branch between the negative electrode of the battery to be detected and the common end of the second resistor and the second insulation resistor.

[0010] As a preferred solution of the utility model, the sampling module includes a step-down circuit, a conditioning circuit and a filtering circuit; the step-down circuit is electrically connected to the conditioning circuit, the conditioning circuit is electrically connected to the filtering circuit, and the filtering circuit is electrically connected to the processing module; the collection end of the sampling module includes the input end of the step-down circuit.

[0011] As a preferred solution of the utility model, the signal generating module includes: a data selector, the input end of the data selector is electrically connected to the processing module; the first chip select end and the third chip select end of the data selector are electrically connected to the positive pole of the power input, and the second chip select end and the fourth chip select end of the data selector are electrically connected to the negative pole of the power input; a first amplifier, the first input end of the first amplifier includes a first in-phase input end, and the first in-phase input end is electrically connected to the output end of the data selector; the second input end of the first amplifier includes a first inverting input end, and the first inverting input end is electrically connected to the output end of the first amplifier.

[0012] As a preferred solution of the utility model, the step-down circuit includes: a second amplifier, the first input end of the second amplifier includes a second inverting input end, the second inverting input end is electrically connected to the output end of the second amplifier and the output end of the first amplifier; the second input end of the second amplifier includes a second non-inverting input end, and the second non-inverting input end is grounded.

[0013] As a preferred solution of the utility model, the conditioning circuit includes: a third amplifier, the first input end of the third amplifier includes a third non-inverting input end, and the third non-inverting input end is electrically connected to the first voltage; the second input end of the third amplifier includes a third inverting input end, and the third inverting input end is electrically connected to the output end of the second amplifier; the output end of the third amplifier is electrically connected to the third inverting input end of the third amplifier.

[0014] As a preferred solution of the utility model, the filtering circuit includes: a fourth amplifier, the first input end of the fourth amplifier includes a fourth non-inverting input end, and the fourth non-inverting input end is electrically connected to the output end of the third amplifier; the second input end of the fourth amplifier includes a fourth inverting input end, and the fourth inverting input end is electrically connected to the output end of the fourth amplifier; the output end of the fourth amplifier is electrically connected to the processing module; a first capacitor, one end of the first capacitor is electrically connected to the fourth non-inverting input end of the fourth amplifier, and the other end of the first capacitor is electrically connected to the output end of the fourth amplifier; a second capacitor, one end of the second capacitor is electrically connected to the fourth non-inverting input end of the fourth amplifier, and the other end of the second capacitor is grounded.

[0015] In another aspect, the present application provides an insulation detection device, including a communication circuit and also provided with any one of the circuit structures described above.

[0016] like Figure 1 As shown, the signal generating module 10 is electrically connected to the battery module 11, the sampling module 12 is electrically connected to the signal generating module 10 and the battery module 11, the processing module 13 is electrically connected to the sampling module 12, the signal generating module 10 is used to generate a positive pulse voltage signal and a negative pulse voltage signal, the sampling module 12 is used to collect the positive pulse voltage signal and the negative pulse voltage signal and the voltage of the battery module, and the processing module 13 is used to perform insulation detection according to the voltage data collected by the sampling module 12.

[0017] Optional, such as Figure 2As shown, the battery module 11 includes a battery to be detected Udc, a first insulation resistor R+, a second insulation resistor R-, a first resistor R1, a second resistor R2, and a third resistor Rm, one end of the first insulation resistor R+ is electrically connected to the positive electrode of the battery to be detected Udc, the other end of the first insulation resistor R+ is grounded, one end of the second insulation resistor R- is electrically connected to the negative electrode of the battery to be detected Udc, the other end of the second insulation resistor R- is grounded, one end of the first resistor R1 is electrically connected to the positive electrode of the battery to be detected Udc and one end of the first insulation resistor R+, one end of the second resistor R2 is electrically connected to the negative electrode of the battery to be detected Udc and one end of the second insulation resistor R-, one end of the third resistor Rm is grounded, and the other end of the third resistor Rm is electrically connected to the common end of the first resistor R1 and the second resistor R2; the signal generating module 10 inputs a pulse voltage signal Us between the third resistor Rm and the ground end, the pulse voltage signal includes a positive pulse voltage signal and a negative pulse voltage signal, and the positive pulse voltage signal and the negative pulse voltage signal are two DC pulse voltage signals with equal amplitudes and a phase difference of 180°.

[0018] Optional, such as Figure 3 As shown, the sampling module 12 includes a first sampling module 121, a second sampling module 122, a third sampling module 123, and a fourth sampling module 124. The acquisition end of the first sampling module 121 is electrically connected to the signal generating module 10. The first sampling module 121 is used to collect positive voltage pulse signals and negative voltage pulse signals. The acquisition end of the second sampling module 122 is electrically connected to the common end of the first resistor R1 and the second resistor R2. The second sampling module 122 is used to collect the reference voltage to the ground at the connection point of the first resistor R1 and the second resistor R2. The acquisition end of the third sampling module 123 is set on the branch between the positive electrode of the battery to be detected Udc and the common end of the first resistor R1 and the first insulation resistor R+. The acquisition end of the fourth sampling module 124 is set on the branch between the negative electrode of the battery to be detected Udc and the common end of the second resistor R2 and the second insulation resistor R-. The third sampling module 123 and the fourth sampling module 124 are used to collect the voltages at both ends of the battery to be detected Udc.

[0019] Optional, such as Figure 4As shown, the signal generating module 10 includes a data selector 101 and a first amplifier 102. The input end of the data selector 101 is electrically connected to the processing module 13. The first chip select end Y1 and the third chip select end Y3 of the data selector 101 are electrically connected to the positive pole of the power input. The second chip select end Y2 and the fourth chip select end Y4 of the data selector 101 are electrically connected to the negative pole of the power input. The first in-phase input end of the first amplifier 102 is electrically connected to the output end of the data selector 101. The first inverting input end of the first amplifier 102 is electrically connected to the output end of the first amplifier 102. One end of the twelfth resistor R12 is electrically connected to the first inverting input end of the first amplifier 102. The other end of the twelfth resistor R12 is grounded. One end of the thirteenth resistor R13 is electrically connected to the first inverting input end of the first amplifier 102. The other end of the thirteenth resistor R13 is electrically connected to the output end of the first amplifier 102.

[0020] Optional, such as Figure 5 As shown, the sampling module 12 includes a step-down circuit 1211, a conditioning circuit 1212 and a filtering circuit 1213. The step-down circuit 1211 is electrically connected to the conditioning circuit 1212, the conditioning circuit 1212 is electrically connected to the filtering circuit 1213, the filtering circuit 1213 is electrically connected to the processing module 13, the collection end of the sampling module 12 includes the input end of the step-down circuit 1211, the step-down circuit includes a second amplifier U2, a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6, the second inverting input end of the second amplifier U2 is electrically connected to the output end of the second amplifier U2, the second non-inverting input end of the second amplifier U2 is grounded, one end of the fourth resistor R4 is electrically connected to the second inverting input end of the second amplifier U2, one end of the fifth resistor R5 is electrically connected to the second inverting input end of the second amplifier U2, the other end of the fifth resistor R5 is electrically connected to the output end of the second amplifier U2, one end of the sixth resistor R6 is electrically connected to the second non-inverting input end of the second amplifier U2, and the other end of the sixth resistor R6 is grounded.

[0021] The conditioning circuit 1212 includes a third amplifier U3, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, and a tenth resistor R10. The third non-inverting input terminal of the third amplifier U3 is electrically connected to the first voltage Vref, the third inverting input terminal of the third amplifier U3 is electrically connected to the output terminal of the second amplifier U2, the output terminal of the third amplifier U3 is electrically connected to the third inverting input terminal of the third amplifier U3, one end of the seventh resistor R7 is electrically connected to the output terminal of the second amplifier U2, the other end of the seventh resistor R7 is electrically connected to the third inverting input terminal of the third amplifier U3, one end of the eighth resistor is electrically connected to the third inverting input terminal of the third amplifier U3, the other end of the eighth resistor is electrically connected to the output terminal of the third amplifier U3, one end of the ninth resistor is electrically connected to the third non-inverting input terminal of the third amplifier U3, the other end of the ninth resistor is electrically connected to the first voltage Vref, one end of the tenth resistor is electrically connected to the third non-inverting input terminal of the third amplifier U3, and the other end of the tenth resistor is grounded.

[0022] The filtering circuit 1213 includes a fourth amplifier U4, a first capacitor C1, a second capacitor C2, and an eleventh resistor R11. The fourth non-inverting input terminal of the fourth amplifier U4 is electrically connected to the output terminal of the third amplifier U3, the fourth inverting input terminal of the fourth amplifier U4 is electrically connected to the output terminal of the fourth amplifier U4, the output terminal of the fourth amplifier U4 is electrically connected to the processing module 13, one end of the first capacitor C1 is electrically connected to the fourth non-inverting input terminal of the fourth amplifier U4, the other end of the first capacitor C1 is electrically connected to the output terminal of the fourth amplifier U4, one end of the second capacitor C2 is electrically connected to the fourth non-inverting input terminal of the fourth amplifier U4, the other end of the second capacitor C2 is grounded, one end of the eleventh resistor R11 is electrically connected to the output terminal of the third amplifier U3, and the other end of the eleventh resistor R11 is electrically connected to the fourth non-inverting input terminal of the fourth amplifier U4.

[0023] like Figure 6 As shown, the insulation detection device includes an insulation detection circuit and a communication circuit 14. The communication circuit 14 is electrically connected to the insulation detection circuit through a processing module 13 and is used to communicate with an external device. The communication circuit 14 can be CAN communication, RS485 communication, or Ethernet communication. When it is detected that the first insulation resistance R+ or the second insulation resistance R- is lower than a set first threshold, the processing module 13 outputs the insulation resistance value and sends an alarm signal.

[0024] An insulation detection circuit and detection device according to the embodiments of the present application have the following beneficial effects: the utility model can accurately measure the resistance value of the insulation resistance through the cooperation of the signal generating module, the battery module, the sampling module, and the processing module, thereby avoiding false alarms or missed alarms of insulation and improving circuit safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic structural block diagram of an insulation detection circuit according to a specific embodiment of the present application.

[0026] Figure 2 It is a circuit diagram of a battery module according to a specific embodiment of the present application.

[0027] Figure 3 It is a schematic structural block diagram of an insulation detection circuit according to another specific embodiment of the present application.

[0028] Figure 4 It is a circuit diagram of a signal generating module according to a specific embodiment of the present application.

[0029] Figure 5 It is a circuit diagram of a sampling module according to a specific embodiment of the present application.

[0030] Figure 6 It is a schematic structural block diagram of an insulation detection device according to a specific embodiment of the present application.

[0031] Figure 7 It is a flowchart of an insulation detection method according to a specific embodiment of the present application. DETAILED DESCRIPTION

[0032] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present application. However, it is apparent to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present application, some technical features well known in the art are not described.

[0033] It should be understood that the present application can be implemented in different forms and should not be construed as being limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete and fully convey the scope of the present application to those skilled in the art. In the accompanying drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0034] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present application, the first element, component, region, layer or part discussed below can be represented as a second element, component, region, layer or part.

[0035] Spatially relative terms such as "under," "below," "below," "under," "above," "above," etc., may be used herein for ease of description to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, the spatially relative terms are intended to include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, then the elements or features described as "under other elements" or "under" or "under" will be oriented as "on" the other elements or features. Therefore, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be oriented otherwise (rotated 90 degrees or other orientations) and the spatial descriptors used herein are interpreted accordingly.

[0036] Some implementation methods of the present utility model are described in detail below in conjunction with the accompanying drawings.

[0037] The signal generating module 10 is used to generate positive pulse voltage signals and negative pulse voltage signals. In one cycle, the voltage generated in the positive half cycle is U S + , the voltage generated in the negative half cycle is U S - In an ideal situation, C is a constant and can be 8, 10, or 30. The voltage signal is injected between the third resistor Rm and the ground.

[0038] The specific implementation of the signal generating module 10 is as follows: Figure 4As shown, the circuit is composed of a four-to-one data selector 74153 and a first amplifier 102. The address input terminals A1 and A0 of 74153 are connected to the I / O terminal of the processing module 13, the chip selection terminal Y3=Y1=Vcc, Y2=Y0=-Vcc, and generally, Vcc can be 2.5V; the output terminal Y of 74153 is connected to the input terminal of the first amplifier 102; the single-chip microcomputer can realize a pulse voltage signal with a positive half-cycle voltage of Vcc and a negative half-cycle voltage of -Vcc by controlling the output of I / O.

[0039] The first amplifier 102 includes a twelfth resistor R12, a thirteenth resistor R13 and a first operational amplifier U1. The input end of the first amplifier 102 is connected to the positive input end of the first operational amplifier U1; the negative input end of the first operational amplifier U1 is connected between the twelfth resistor R12 and the thirteenth resistor R13, the other end of the twelfth resistor R12 is grounded, and the thirteenth resistor R13 is electrically connected to the output end of the first operational amplifier U1. The amplification factor of the first amplifier 102 is changed by adjusting the ratio of the twelfth resistor R12 and the thirteenth resistor R13, thereby achieving amplification of the pulse voltage signal.

[0040] The specific implementation of the sampling module 12 is as follows: Figure 5 As shown, the sampling module 12 includes a first sampling module 121 , a second sampling module 122 , a third sampling module 123 and a fourth sampling module 124 , and the first sampling module 121 is taken as an example for specific description.

[0041] The first sampling module 121 is composed of a step-down circuit 1211, a conditioning circuit 1212 and a filtering circuit 1213. The step-down circuit 1211 includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6 and a second amplifier U2. The negative input terminal of the second amplifier U2 is connected between the fourth resistor R4 and the fifth resistor R5. The other end of the fourth resistor R4 is the input terminal of the step-down circuit 1211, which is connected to the output terminal of the signal generating module 10. The other end of the fifth resistor R5 is connected to the output terminal of the second amplifier U2. The positive input terminal of the second amplifier U2 is connected to the ground through the sixth resistor R6. Generally, the sixth resistor R6 is called a balancing resistor, and R6=R4 / R5 is usually taken. By adjusting the ratio of R4 and R5, the reduction factor of the step-down circuit 1211 is changed, thereby reducing the sampling voltage.

[0042] The conditioning circuit 1212 includes a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10 and a third amplifier U3. The positive input terminal of the third amplifier U3 is connected to the reference voltage Vref through the ninth resistor R9, one end of the tenth resistor R10 is grounded, and the other end is connected to the positive input terminal of the third amplifier U3; the negative input terminal of the third amplifier U3 is connected between the seventh resistor R7 and the eighth resistor R8, the other end of the seventh resistor R7 is connected to the output terminal of the step-down circuit 1211, and the other end of the eighth resistor R8 is connected to the output terminal of the third amplifier U3; by setting the seventh resistor R7, the eighth resistor R8, the ninth resistor R9, and the tenth resistor R10, the sampling signal can be raised to a certain value to ensure that the sampling voltage range is within the normal acquisition range of the processing module 13.

[0043] The filter circuit 1213 includes an eleventh resistor R11, a first capacitor C1, a second capacitor C2 and a fourth operational amplifier U4. The first capacitor C1 and the second capacitor C2 are both ordinary chip capacitors, which have the function of isolating direct current and passing alternating current. The positive input terminal of the fourth amplifier U4 is connected to the output terminal of the third amplifier U3 through the eleventh resistor R11; the positive input terminal of the fourth amplifier U4 is connected to the ground through the second capacitor C2; the negative input terminal of the fourth amplifier U4 is connected to the output terminal of the fourth amplifier U4; the output terminal of the fourth amplifier U4 is connected through the first capacitor C1. This circuit is a first-order RC low-pass filter, which can filter out the high-frequency noise of the environment and the high-frequency ripple of the signal source through a low-frequency signal to avoid causing deviations in the sampling results.

[0044] like Figure 2 As shown, the voltage across the battery to be tested is Udc, the sampling resistor is Rm, R1 and R2 are the positive branch voltage divider resistor and the negative branch voltage divider resistor respectively; R+ and R- are the insulation resistance of the positive electrode of the battery to the ground and the insulation resistance of the negative electrode of the battery to the ground respectively; Us is the injected voltage signal of the signal generator, in one cycle, the positive half cycle and the negative half cycle have equal amplitudes and two DC pulse voltage signals with a phase difference of 180°. Taking the earth as the reference 0 potential, let the potential at the connection point of Rm and R1 be Um, also called the sampling resistor potential; the potential at the connection point of the negative electrode of the battery and R2 is U-; the potential at the connection point of the positive electrode of the battery and R1 is U+; the output current of the battery branch is I. Using the node voltage analysis method, we get:

[0045] At the connection point of Rm and R1:

[0046] (1 / R m +1 / R1+1 / R2)U m -1 / R1·U + -1 / R2·U - =U s / R m (1)

[0047] At the junction of the negative battery terminal and R2:

[0048] (1 / R1+1 / R + ) + -1 / R1·U m =I (2)

[0049] At the junction of the positive battery terminal and R1:

[0050] (1 / R2+1 / R - ) + -1 / R2·U m =-I (3)

[0051] The voltage at the junction of the negative battery and R2 and the junction of the positive battery and R1 is:

[0052] U + -U - =U dc (4)

[0053] Combining equations (1)(2)(3)(4), eliminating U+ and U-, we get:

[0054]

[0055] In the positive half cycle, the injected voltage of the voltage signal Us injected by the signal generator is Us+, and the corresponding sampling resistor potential is Um+. Substituting into formula (5), we get:

[0056]

[0057] In the negative half cycle, the injected voltage of the voltage signal Us injected by the signal generator is Us-, and the corresponding sampling resistor potential is Um-. Substituting into formula (5), we get:

[0058]

[0059] Combining (6) and (7), we get:

[0060]

[0061]

[0062] In formulas (8) and (9):

[0063]

[0064]

[0065] like Figure 7As shown, in step S1, the sampling module 12 has sampled the sampling values ​​of Udc, Us+, Us-, Um+, and Um-, and the processing module can read the sampling values ​​of each voltage; in step S2, in formula (10) and formula (11), R and Rm are known values, and Us+, Us-, Um+, Um-, and Udc are substituted into the expressions of c and d to obtain the values ​​of c and d; in step S3, c and d and the sampling values ​​in step S2 are substituted into the expressions of R+ and R- to obtain the insulation resistance R+ of the positive electrode of the battery to the ground and the insulation resistance R- of the negative electrode of the battery to the ground; in step S4, the processing module 13 determines whether R+ or R- is less than the set first threshold value. If R+ or R- is less than the set first threshold value, the processing module 13 confirms that the circuit insulation fails and outputs the specific R+ and R- values; if the value of R+ or R- is not less than the set first threshold value, the processing module outputs normal.

[0066] The utility model inputs two DC pulse voltage signals with equal amplitude and 180° phase difference between the sampling resistor in the battery module and the ground terminal, and collects the reference potential of the ground at the connection point of the first resistor and the second resistor, the voltage at both ends of the battery to be detected, and the voltage signal of the signal generating circuit through the sampling module. The resistance values ​​of the first insulation resistor and the second insulation resistor can be accurately calculated according to the collected signals through the processing module. The resistance values ​​of the first insulation resistor and the second insulation resistor are obtained respectively, and the polarity of the grounding busbar can be identified, saving manpower and material resources for searching and measuring, and improving work efficiency. At the same time, accurately knowing the resistance values ​​of the first insulation resistor and the second insulation resistor can avoid false insulation reports and omissions, thereby causing harm to people and property. When the positive and negative insulation resistances are both reduced or their values ​​are close, or one end is grounded, the utility model can accurately measure.

[0067] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application to this. Those of ordinary skill in the art may make various changes and modifications therein without departing from the scope and spirit of the present application. All these changes and modifications are intended to be included within the scope of the present application as required by the appended claims.

[0068] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various application aspects, in the description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present application should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the corresponding claims, the application point is that the corresponding technical problem can be solved with less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are hereby explicitly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0069] In addition, those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0070] It should be noted that the above embodiments illustrate rather than limit the present application, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets should not be construed as a limitation to the claims. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names.

Claims

1. An insulation detection circuit, characterized in that: The insulation detection circuit comprises: A signal generating module, the signal generating module is electrically connected to the power supply, and the signal generating module is used to generate a positive pulse voltage signal and a negative pulse voltage signal; A battery module, the battery module comprising a battery to be detected, a first insulation resistor and a second insulation resistor, the battery module being electrically connected to the signal generating module; A sampling module, the sampling module comprising a collection end, the collection end is electrically connected to the signal generating module and the battery module, and the sampling module is used to collect the positive pulse voltage signal, the negative pulse voltage signal and the voltage of the battery module; A processing module, wherein the processing module is electrically connected to the signal generating module and the sampling module, and the processing module is used to obtain the first insulation resistance of the battery to be detected and the second insulation resistance of the battery to be detected according to the voltage data collected by the sampling module, and the first insulation resistance and the second insulation resistance are used to determine whether the battery module insulation fails.

2. The insulation detection circuit according to claim 1, characterized in that: When the resistance value of the first insulation resistor or the resistance value of the second insulation resistor is less than a first threshold, the insulation of the battery module fails.

3. The insulation detection circuit according to claim 1, characterized in that: One end of the first insulation resistor is electrically connected to the positive electrode of the battery to be detected, and the other end of the first insulation resistor is grounded; One end of the second insulation resistor is electrically connected to the negative electrode of the battery to be detected, and the other end of the second insulation resistor is grounded.

4. The insulation detection circuit according to claim 2, characterized in that: The battery module further comprises: a first resistor and a second resistor, wherein one end of the first resistor is electrically connected to the positive electrode of the battery to be detected and one end of the first insulation resistor, and one end of the second resistor is electrically connected to the negative electrode of the battery to be detected and one end of the second insulation resistor; A third resistor, one end of which is grounded, and the other end of which is electrically connected to a common end of the first resistor and the second resistor.

5. According to the claim 4 The insulation detection circuit is characterized in that: The signal generating module inputs the positive pulse voltage signal and the negative pulse voltage signal between the third resistor and the ground terminal. The positive pulse voltage signal and the negative pulse voltage signal are two DC pulse voltage signals with equal amplitudes and a phase difference of 180°.

6. According to the claim 4 The insulation detection circuit is characterized in that: The sampling module comprises: A first sampling module, wherein a collection end of the first sampling module is electrically connected to the signal generating module, and the first sampling module is used to collect a voltage signal of a signal generating circuit; a second sampling module, wherein a collection end of the second sampling module is electrically connected to a common end of the first resistor and the second resistor; A third sampling module, wherein a collection end of the third sampling module is arranged on a branch between the positive electrode of the battery to be detected and a common end of the first resistor and the first insulation resistor; A fourth sampling module, wherein a collection end of the fourth sampling module is arranged on a branch circuit at a common end of the negative electrode of the battery to be detected and the second resistor and the second insulation resistor.

7. The insulation detection circuit according to claim 1, characterized in that: The sampling module includes a step-down circuit, a conditioning circuit and a filtering circuit; The step-down circuit is electrically connected to the conditioning circuit, the conditioning circuit is electrically connected to the filtering circuit, and the filtering circuit is electrically connected to the processing module; The collection end of the sampling module includes the input end of the buck circuit.

8. According to the claim 7 The insulation detection circuit is characterized in that: The signal generating module comprises: A data selector, wherein an input end of the data selector is electrically connected to the processing module; a first chip select end and a third chip select end of the data selector are electrically connected to an input positive electrode of the power supply, and a second chip select end and a fourth chip select end of the data selector are electrically connected to an input negative electrode of the power supply; a first amplifier, wherein a first input terminal of the first amplifier comprises a first non-inverting input terminal, and the first non-inverting input terminal is electrically connected to an output terminal of the data selector; The second input terminal of the first amplifier includes a first inverting input terminal, and the first inverting input terminal is electrically connected to the output terminal of the first amplifier.

9. According to Claim 8 The insulation detection circuit is characterized in that: The step-down circuit comprises: a second amplifier, wherein the first input terminal of the second amplifier comprises a second inverting input terminal, and the second inverting input terminal is electrically connected to the output terminal of the second amplifier and the output terminal of the first amplifier; The second input terminal of the second amplifier includes a second non-inverting input terminal, and the second non-inverting input terminal is grounded.

10. According to Claim 9 The insulation detection circuit is characterized in that: The conditioning circuit comprises: a third amplifier, wherein the first input terminal of the third amplifier comprises a third in-phase input terminal, and the third in-phase input terminal is electrically connected to the first voltage; The second input terminal of the third amplifier includes a third inverting input terminal, and the third inverting input terminal is electrically connected to the output terminal of the second amplifier; The output terminal of the third amplifier is electrically connected to the third inverting input terminal of the third amplifier. 11.According to Claim 10 The insulation detection circuit is characterized in that: The filtering circuit comprises: a fourth amplifier, wherein the first input end of the fourth amplifier comprises a fourth non-inverting input end, and the fourth non-inverting input end is electrically connected to the output end of the third amplifier; the second input end of the fourth amplifier comprises a fourth inverting input end, and the fourth inverting input end is electrically connected to the output end of the fourth amplifier; and the output end of the fourth amplifier is electrically connected to the processing module; a first capacitor, one end of the first capacitor being electrically connected to the fourth in-phase input terminal of the fourth amplifier, and the other end of the first capacitor being electrically connected to the output terminal of the fourth amplifier; A second capacitor, one end of the second capacitor is electrically connected to the fourth non-inverting input terminal of the fourth amplifier, and the other end of the second capacitor is grounded.

12. An insulation detection device, characterized in that: A communication circuit is also provided, wherein the Insulation testing Circuit.

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