Insulation detection method, device and equipment, battery management controller and storage medium

Abstract

The invention discloses an insulation detection method, device and equipment, a battery management controller and a storage medium, and the method comprises the steps: obtaining corresponding first sampling voltage data and second sampling voltage data sampled by a first sampling point and a second sampling point in a preset sampling period when a first power supply supplies power, and obtaining corresponding second sampling voltage data sampled by a second sampling point in a preset sampling period when a second power supply supplies power; the first sampling point and the second sampling point respectively sample corresponding third sampling voltage data and fourth sampling voltage data in a preset sampling time period; obtaining first voltage threshold data, second voltage threshold data, third voltage threshold data and fourth voltage threshold data according to the obtained first sampling voltage data, second sampling voltage data, third sampling voltage data and fourth sampling voltage data; and determining the insulation state of the load based on the sampled voltage data and the corresponding voltage threshold data. The real insulation failure state can be distinguished, and the accuracy of insulation state detection and the stability of insulation detection are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery management, and in particular to an insulation detection method, device, equipment, a battery management controller and a storage medium. Background Art

[0002] In the related art, it is usually necessary to wait for the voltage to stabilize and only use the stable sampling voltage to calculate the insulation resistance, and then perform insulation detection based on the insulation resistance. However, in the process of voltage sampling, since the insulation resistance and the size of the Y capacitor in the circuit will affect the stabilization time of the system, when the insulation resistance is large, there is a fixed Y capacitor and the detection time is limited, the voltage at the sampling point cannot reach a stable state, and the sampled voltage obtained in this way is also unstable, so that the insulation resistance is calculated based on the unstable sampling voltage, and then the insulation detection is performed based on the insulation resistance, which easily triggers the insulation alarm threshold and cannot distinguish the real insulation failure, resulting in low reliability and accuracy of the insulation detection results. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0004] Therefore, an object of the present invention is to provide an insulation detection method, which can reduce the probability of false alarm of insulation status and improve the accuracy and reliability of insulation detection.

[0005] Therefore, a second object of the present invention is to provide an insulation detection device.

[0006] To this end, a third object of the present invention is to provide an insulation detection device.

[0007] To this end, a fourth objective of the present invention is to provide a battery management control system.

[0008] To this end, a fifth object of the present invention is to provide a computer-readable storage medium.

[0009] To achieve the above-mentioned purpose, the first aspect of the present invention discloses an insulation detection method for an insulation detection circuit, wherein the insulation detection circuit includes a power module, a first sampling point, a second sampling point and an insulation resistor, wherein the power module can provide a first power supply or a second power supply, the voltages output by the first power supply and the second power supply are different, the first sampling point is connected to the positive terminal of the power module, the first sampling point is also connected to the first ground terminal and one end of the insulation resistor through a first resistor, the second sampling point is respectively connected to the second ground terminal and the negative terminal of the power module through a second resistor, the second sampling point is also connected to the first sampling point through a third resistor, and the negative terminal of the power module is also connected to the second ground terminal and the other end of the insulation resistor through a fourth resistor, the insulation detection method includes: obtaining first sampling voltage data sampled by the first sampling point within a preset sampling period and the second sampling voltage data sampled by the first sampling point within a preset sampling period when the first power supply is supplied. The method comprises the following steps: obtaining a second sampled voltage data sampled at a voltage sampling point within a preset sampling period, and obtaining a third sampled voltage data sampled at the first sampling point within a preset sampling period and a fourth sampled voltage data sampled at the second voltage sampling point within a preset sampling period when the second power supply is supplied; obtaining first voltage threshold data corresponding to the first sampled voltage data, and obtaining second voltage threshold data corresponding to the second sampled voltage data, and obtaining third voltage threshold data corresponding to the third sampled voltage data, and obtaining fourth voltage threshold data corresponding to the fourth sampled voltage data; determining an insulation state of a load based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state.

[0010] According to the insulation detection method of the embodiment of the invention, the first power supply and the second power supply can be switched with each other. When the first power supply is powered, the first sampled voltage data sampled at the first sampling point within the preset sampling period and the second sampled voltage data sampled at the second sampling point within the preset sampling period are obtained. When the power supply is switched to the second power supply, the third sampled voltage data sampled at the first sampling point within the preset sampling period and the fourth sampled voltage data sampled at the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data. In this way, the stability of the voltage data may be affected by the interference of the insulation resistance of the single grounding terminal, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0011] In addition, the insulation detection method according to the above embodiment of the present invention may also have the following additional technical features:

[0012] In some embodiments, the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state, including: when the first sampled voltage data is greater than the first voltage threshold data, and the second sampled voltage data is greater than the second voltage threshold data, and the third sampled voltage data is greater than the third voltage threshold data, and the fourth sampled voltage data is greater than the fourth voltage threshold data, the insulation state of the load is determined to be a normal insulation state; otherwise, the insulation state of the load is determined to be an insulation failure state.

[0013] In some embodiments, the preset sampling period includes multiple sampling moments from back to front according to the sampling time; the first sampled voltage data is obtained by averaging a plurality of voltage data correspondingly sampled by the first sampling point at the plurality of sampling moments when the first power supply is supplied; the second sampled voltage data is obtained by averaging a plurality of voltage data correspondingly sampled by the second sampling point at the plurality of sampling moments when the first power supply is supplied; the third sampled voltage data is obtained by averaging a plurality of voltage data correspondingly sampled by the first sampling point at the plurality of sampling moments when the second power supply is supplied; the fourth sampled voltage data is obtained by averaging a plurality of voltage data correspondingly sampled by the second sampling point at the plurality of sampling moments when the second power supply is supplied.

[0014] In some embodiments, the obtaining of first voltage threshold data corresponding to the first sampled voltage data, and the obtaining of second voltage threshold data corresponding to the second sampled voltage data, include: when a first reference resistor is used as the insulation resistor and the power is supplied by the first power supply, obtaining a first reference voltage corresponding to the first sampling point at a preset sampling time and a second reference voltage corresponding to the second sampling point at the preset sampling time; when a second reference resistor is used as the insulation resistor and the power is supplied by the first power supply, obtaining a third reference voltage corresponding to the first sampling point at the preset sampling time and a fourth reference voltage corresponding to the second sampling point at the preset sampling time, wherein the resistance of the first reference resistor is less than the resistance of the second reference resistor; determining the first voltage threshold data according to the first reference voltage and the third reference voltage, and determining the second voltage threshold data according to the second reference voltage and the fourth reference voltage.

[0015] In some embodiments, determining the first voltage threshold data based on the first reference voltage and the third reference voltage, and determining the second voltage threshold data based on the second reference voltage and the fourth reference voltage, include: performing weighted operations on the first reference voltage and the third reference voltage respectively and summing them up to obtain the first voltage threshold data, wherein the weight coefficients corresponding to the first reference voltage and the third reference voltage are respectively preset; performing weighted operations on the second reference voltage and the fourth reference voltage respectively and summing them up to obtain the second voltage threshold data, wherein the weight coefficients corresponding to the second reference voltage and the fourth reference voltage are respectively preset.

[0016] In some embodiments, the obtaining of the third voltage threshold data corresponding to the third sampled voltage data, and the obtaining of the fourth voltage threshold data corresponding to the fourth sampled voltage data, include: when the first reference resistor is used as the insulation resistor and the power is supplied by the second power supply, obtaining a fifth reference voltage corresponding to the first sampling point at a preset sampling time and a sixth reference voltage corresponding to the second sampling point at the preset sampling time; when the second reference resistor is used as the insulation resistor and the power is supplied by the second power supply, obtaining a seventh reference voltage corresponding to the first sampling point at the preset sampling time and an eighth reference voltage corresponding to the second sampling point at the preset sampling time, wherein the resistance of the first reference resistor is less than the resistance of the second reference resistor; determining the third voltage threshold data according to the fifth reference voltage and the seventh reference voltage, and determining the fourth voltage threshold data according to the sixth reference voltage and the eighth reference voltage.

[0017] In some embodiments, determining the third voltage threshold data based on the fifth reference voltage and the seventh reference voltage, and determining the fourth voltage threshold data based on the sixth reference voltage and the eighth reference voltage, include: performing weighted operations on the fifth reference voltage and the seventh reference voltage, respectively, and summing them up to obtain the third voltage threshold data, wherein the weight coefficients corresponding to the fifth reference voltage and the seventh reference voltage are respectively preset; performing weighted operations on the sixth reference voltage and the eighth reference voltage, respectively, and summing them up to obtain the fourth voltage threshold data, wherein the weight coefficients corresponding to the sixth reference voltage and the eighth reference voltage are respectively preset.

[0018] In some embodiments, the preset sampling moment is the last sampling moment in the current sampling cycle.

[0019] In some embodiments, before obtaining the first sampled voltage data sampled by the first sampling point within a preset sampling period and the second sampled voltage data sampled by the second voltage sampling point within a preset sampling period when the first power supply is supplied, and obtaining the third sampled voltage data sampled by the first sampling point within a preset sampling period and the fourth sampled voltage data sampled by the second voltage sampling point within a preset sampling period when the second power supply is supplied, it also includes: judging whether the resistance value of the insulation resistance is less than a preset alarm threshold; if so, executing the steps of obtaining the first sampled voltage data sampled by the first sampling point within a preset sampling period and the second sampled voltage data sampled by the second voltage sampling point within a preset sampling period when the first power supply is supplied, and obtaining the third sampled voltage data sampled by the first sampling point within a preset sampling period and the fourth sampled voltage data sampled by the second voltage sampling point within a preset sampling period when the second power supply is supplied; otherwise, determining that the load is in a normal insulation state.

[0020] To achieve the above-mentioned purpose, an embodiment of a second aspect of the present invention discloses an insulation detection device, which is used for an insulation detection circuit. The insulation detection circuit includes a power supply module, a first sampling point, a second sampling point and an insulation resistor, wherein the power supply module can provide a first power supply or a second power supply, and the voltages output by the first power supply and the second power supply are different. The first sampling point is connected to the positive terminal of the power supply module, and the first sampling point is also connected to the first ground terminal and one end of the insulation resistor through a first resistor. The second sampling point is respectively connected to the second ground terminal and the negative terminal of the power supply module through a second resistor. The second sampling point is also connected to the first sampling point through a third resistor, and the negative terminal of the power supply module is also connected to the second ground terminal and the other end of the insulation resistor through a fourth resistor. The insulation detection device includes: a first acquisition module, which is used to acquire first sampled voltage data and second sampled voltage data sampled by the first sampling point within a preset sampling period when the first power supply is supplied. a second sampling voltage data sampled at a sampling point within a preset sampling period, and a third sampling voltage data sampled at the first sampling point within a preset sampling period and a fourth sampling voltage data sampled at the second voltage sampling point within a preset sampling period when the second power supply is supplied; a second obtaining module, used to obtain first voltage threshold data corresponding to the first sampling voltage data, and obtain second voltage threshold data corresponding to the second sampling voltage data, and obtain third voltage threshold data corresponding to the third sampling voltage data, and obtain fourth voltage threshold data corresponding to the fourth sampling voltage data; a determining module, used to determine the insulation state of the load based on the first sampling voltage data, the first voltage threshold data, the second sampling voltage data, the second voltage threshold data, the third sampling voltage data, the third voltage threshold data, the fourth sampling voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state.

[0021] According to the insulation detection device of the embodiment of the present invention, when the power is supplied by the first power supply, the first acquisition module acquires the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period. When the power is switched to the second power supply, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are acquired. In this sampling process, the first grounding terminal and the second grounding terminal are used to acquire the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data. In this way, the stability of the voltage data may be affected by the interference of the insulation resistance of the single grounding terminal, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data acquired within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then the second acquisition module also needs to obtain the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data. The determination module determines the insulation state of the load based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, determines whether the load is in a normal insulation state or an insulation failure state, can distinguish the real insulation failure state, avoids the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0022] To achieve the above-mentioned purpose, an embodiment of the third aspect of the present invention discloses an insulation detection device, comprising: the insulation detection device described in the embodiment of the second aspect of the present invention, or a processor, a memory, and an insulation detection program stored in the memory and executable on the processor, wherein when the insulation detection program is executed by the processor, the insulation detection method described in any one of the embodiments of the first aspect of the present invention is implemented.

[0023] According to the insulation detection device of the embodiment of the present invention, when powered by the first power supply, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. When switched to the second power supply, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data, which can effectively avoid the single grounding terminal from affecting the stability of the voltage data due to the interference of the insulation resistance, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0024] In order to achieve the above-mentioned purpose, the fourth aspect embodiment of the present invention discloses a battery management controller, including the insulation detection device described in the above-mentioned third aspect embodiment of the present invention, or a processor, a memory, and an insulation detection program stored in the memory and executable on the processor, wherein when the insulation detection program is executed by the processor, it implements the insulation detection method described in any one of the embodiments of the first aspect of the present invention.

[0025] According to the battery management controller of the embodiment of the present invention, when powered by the first power source, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. When switched to the second power source for power supply, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data, which can effectively avoid the single grounding terminal possibly affecting the stability of the voltage data due to the interference of the insulation resistance, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0026] To achieve the above-mentioned purpose, an embodiment of the fifth aspect of the present invention discloses a computer-readable storage medium, on which an insulation detection program is stored. When the insulation detection program is executed by a processor, the insulation detection method as described in any embodiment of the first aspect of the present invention is implemented.

[0027] According to the computer-readable storage medium of the embodiment of the present invention, when the insulation detection program stored thereon is executed by the processor, when the power is supplied by the first power source, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period are obtained, and when the power is switched to the second power source, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data, so that the single grounding terminal may effectively avoid the influence of the stability of the voltage data due to the interference of the insulation resistance, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0028] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0030] Figure 1 is a schematic diagram of the insulation detection circuit principle according to an embodiment of the present invention;

[0031] Figure 2 is a schematic diagram of changes in sampling voltage according to an embodiment of the present invention;

[0032] Figure 3is a schematic diagram of the structure of a battery management controller according to an embodiment of the present invention;

[0033] Figure 4 is a flow chart of an insulation detection method according to an embodiment of the present invention;

[0034] Figure 5 is a schematic diagram of a variation trend of a sampling voltage according to an embodiment of the present invention;

[0035] Figure 6 is a flow chart for determining the insulation state of a load according to one embodiment of the present invention;

[0036] Figure 7 is a schematic diagram of changes in sampling voltages of different reference resistors according to an embodiment of the present invention;

[0037] Figure 8 is a schematic diagram of changes in sampling voltages of different reference resistors according to another embodiment of the present invention;

[0038] Fig. 9 is a structural block diagram of an insulation detection device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0039] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0040] like Figure 1 The schematic diagram of the insulation detection circuit shown in the figure includes a power module, a first sampling point A, a second sampling point B and an insulation resistor Riso, and also includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a first ground terminal GND, a second ground terminal GND1 and a vehicle-end Y capacitor, wherein the power module can provide a first power supply or a second power supply, and the voltages output by the first power supply and the second power supply are different. When supplying power, the first power supply and the second power supply can be switched. The first sampling point A is connected to the positive terminal of the power module, and the first sampling point A is also connected to the first ground terminal GND and one end of the insulation resistor Riso through the first resistor R1. The second sampling point B is respectively connected to the second ground terminal GND1 and the negative terminal of the power module through the second resistor R2, and the second sampling point B is also connected to the first sampling point A through the third resistor R3, and the negative terminal of the power module is also connected to the second ground terminal GND1 and the other end of the insulation resistor Riso through the fourth resistor R4.

[0041] The inventors have found that according to Figure 1 When performing insulation testing under large resistance conditions, the circuit schematic diagram shown usually relies on continuously waiting for the voltage to stabilize and only uses the stable sampled voltage to calculate the insulation resistance, and performs insulation testing based on the insulation resistance.

[0042] Specifically, the current insulation detection method under large resistance conditions is, when the first power supply is powered, according to the current formula Vpower / (R3+R2)=|VA-VB| / R3, to inversely deduce the voltage value Vpower of the first power supply, wherein VA is the voltage value corresponding to the first sampling point A when the first power supply is powered; VB is the voltage value corresponding to the second sampling point B when the first power supply is powered, and then according to the fourth resistor R4 and the voltage value VA corresponding to the first sampling point A when the first power supply is powered, the current value IA corresponding to the first sampling point A when the first power supply is powered is obtained, that is, IA=VA / R4.

[0043] Similarly, when the second power supply is powered, the voltage value Vpower' of the first power supply is inversely deduced according to the current formula Vpower' / (R3+R2)=|VA'-VB'| / R3, wherein VA' is the voltage value corresponding to the first sampling point A when the second power supply is powered; VB' is the voltage value corresponding to the second sampling point B when the first power supply is powered, and then according to the fourth resistor R4 and the voltage value VA' corresponding to the first sampling point A when the second power supply is powered, the current value IA' corresponding to the first sampling point A when the second power supply is powered is obtained, that is, IA'=VA' / R4.

[0044] Finally, according to the voltage value Vpower of the first power supply, the voltage value Vpower' of the second power supply, the current value IA corresponding to the first sampling point when the first power supply is powered, the current value IA' corresponding to the first sampling point when the second power supply is powered, the first resistor R1 and the fourth resistor R4, the insulation resistance R is obtained, that is:

[0045] R=|Vpower-Vpower'| / |IA-IA'|-R1-R4

[0046] Among them, the voltage value VA corresponding to the first sampling point A when the first power supply is supplied, the voltage value VB corresponding to the second sampling point B when the first power supply is supplied, and the voltage value VA' corresponding to the first sampling point A when the second power supply is supplied, and the voltage value VB' corresponding to the second sampling point B when the first power supply is supplied, are all obtained by sampling based on the first ground terminal GND. Since the potential across the third resistor R3 will not change, but the potential of the first ground terminal GND will be affected by the insulation resistance Riso of the load, and will change with the change of the insulation resistance Riso of the load, therefore, when obtaining the voltage data across the first sampling point A and the second sampling point B, the first ground terminal GND is used as the reference point for sampling, and the obtained voltage data will also be affected by the insulation resistance Riso of the load, that is, the voltage data obtained at the first sampling point A and the second sampling point B are not voltage data in a stable state. In addition, the size of the Y capacitor at the vehicle end will also affect the stability of the system. Therefore, when the insulation resistance Riso is large, there is a fixed vehicle end Y capacitor and the detection time is limited, the voltage at the sampling point cannot reach a stable state, so that the voltage value VA corresponding to the first sampling point A when the first power supply is supplied and the voltage value VB corresponding to the second sampling point B when the first power supply is supplied, as well as the voltage value VA' corresponding to the first sampling point A when the second power supply is supplied and the voltage value VB' corresponding to the second sampling point B when the first power supply is supplied are also unstable, so that the current value IA corresponding to the first sampling point A when the first power supply is supplied based on the voltage value VA corresponding to the first sampling point A when the first power supply is supplied is also unstable. Similarly, the current value IA' corresponding to the first sampling point A when the second power supply is supplied based on the voltage value VA' corresponding to the first sampling point A when the second power supply is supplied is also unstable. Therefore, the insulation resistance R is obtained based on unstable data, and insulation detection is performed based on the insulation resistance R, which easily triggers the insulation alarm threshold, and cannot distinguish the real insulation failure, resulting in low reliability and accuracy of the insulation detection result.

[0047] Based on the above, an insulation detection method of an embodiment of the present invention is proposed. Since the sampling voltage tends to be stable as the sampling time increases during the sampling process, relatively stable sampling voltage data can be obtained within the preset sampling period. At the same time, the potential of the first ground terminal GND relative to the second ground terminal GND1 can be used to avoid the single ground terminal being affected by the insulation resistance and affecting the stability of the sampling voltage data, thereby improving the stability of the voltage data obtained when sampling the first sampling point A and the second sampling point B. Therefore, using these stable voltage data, the resistance value of the stable insulation resistance is calculated, and the insulation comparison is performed using the resistance of the stable insulation resistance and the preset alarm threshold, which can improve the accuracy of insulation detection. In addition, the embodiment of the present invention also obtains the sampling voltage data corresponding to the first sampling point A and the second sampling point B under different power supplies, and obtains the voltage threshold data corresponding to the different sampling voltage data. Based on these sampling voltage data and the corresponding voltage threshold data, the insulation state of the load is determined, so that the real insulation failure state can be distinguished, and the normal insulation state is avoided from being misjudged as the insulation failure state, thereby reducing the probability of insulation alarm, and improving the accuracy of insulation state detection and the stability of insulation detection.

[0048] As a specific example, Figure 2 As shown, the sampling voltage data of the first sampling point A and the second sampling point B are affected by the change of the insulation resistance Riso and are monotonically changed. Therefore, by sampling the voltage of the insulation resistance Riso from a small resistance value to a large resistance value, the voltage can be obtained. Figure 2 The sampling voltage change diagram shown in Figure 2 It can be seen that under the conditions of large resistance and insulation failure, the voltage value has obvious differences and changes monotonically. Therefore, in order to ensure that the voltage data obtained when sampling the first sampling point A and the second sampling point B is in a stable state, the potential of the first ground terminal GND relative to the second ground terminal GND1 is used to obtain the sampled voltage data of the first sampling point A and the second sampling point B. Specifically, it can be calculated according to the following formula, that is:

[0049] φGND_Power=Vpower / (R4+Riso+R1)*(Riso+R1) (1)

[0050] φB_Power=Vpower / (R3+R2)*R2 (2)

[0051] VA=Vpower-φGND_Power (3)

[0052] VB=φB_Power-φGND_Power (4)

[0053] φB_Power'=Vpower' / (R3+R2)*R2 (5)

[0054] VA'=Vpower'-φGND_Power (6)

[0055] VB'=φB_Power'-φGND_Power (7)

[0056] Among them, φGND_Power is the potential of the first ground terminal GND relative to the second ground terminal GND1 when the first power supply is powered by the first power supply, Vpower is the voltage value of the first power supply, VA is the voltage value corresponding to the first sampling point when the first power supply is powered by the first power supply, VB is the voltage value corresponding to the second sampling point when the first power supply is powered by the first power supply, φGND_Power' is the potential of the first ground terminal GND relative to the second ground terminal GND1 when the second power supply is powered by the second power supply, Vpower' is the voltage value of the second power supply, VA' is the voltage value corresponding to the first sampling point when the second power supply is powered by the second power supply, and VB' is the voltage value corresponding to the second sampling point when the second power supply is powered by the second power supply.

[0057] Then, the current value IA corresponding to the first sampling point when the first power source is supplying power and the current value IA' corresponding to the first sampling point when the second power source is supplying power are calculated, that is:

[0058] Vpower / (R3+R2)=|VA-VB| / R3 (8)

[0059] IA=VA / R4 (9)

[0060] Vpower'(R3+R2)=|VA'-VB'| / R3 (10)

[0061] IA'=VA' / R4 (11)

[0062] In this way, the resistance value R' of the insulation resistance Riso can be calculated according to the current value IA corresponding to the first sampling point when the first power supply is powered, the current value IA' corresponding to the first sampling point when the second power supply is powered, the voltage value Vpower of the first power supply, and the voltage value Vpower' of the second power supply, and then according to the first resistor R1 and the fourth resistor R4, that is, R'=|Vpower-Vpower'| / |IA-IA'|-R4-R1.

[0063] Therefore, compared with the sampled voltage data obtained by sampling only using the first ground terminal GND, the sampled voltage data obtained by sampling according to the first ground terminal GND and the second ground terminal GND1 is relatively stable, and the resistance value of the insulation resistance obtained according to the stable sampled voltage data is also stable. Therefore, when insulation detection is performed using the comparison result of the stable insulation resistance value and the preset alarm threshold, the accuracy of insulation detection is effectively improved.

[0064] Specifically, in an embodiment of the present invention, the battery management controller can provide a first power supply or a second power supply, that is, the battery management controller can control the switching between the first power supply and the second power supply. When the first power supply is needed, the battery management controller provides the first power supply for the entire insulation detection equipment. When the second power supply is needed, the battery management controller will provide the second power supply for the entire insulation detection equipment. In this way, the voltage difference between the first power supply and the second power supply, as well as the sampled voltage data and the corresponding voltage threshold data obtained under different power supply conditions, can be utilized to improve the accuracy of insulation detection.

[0065] like Figure 3 , which is a schematic diagram of the structure of a battery management controller, wherein the battery management controller includes, for example, an insulation detection device, an analog-to-digital converter, and a microcontroller.

[0066] like Figure 3 As shown, the insulation detection device is connected to the high voltage interface and the first ground terminal respectively, and the insulation detection device can provide the sampled voltage of the sampling point to the analog-to-digital converter, that is, the voltage value VA corresponding to the first sampling point A when the first power supply is powered and the voltage value VB corresponding to the second sampling point B when the first power supply is powered, or the voltage value VA' corresponding to the first sampling point A when the second power supply is powered and the voltage value VB' corresponding to the second sampling point B when the second power supply is powered. The analog-to-digital converter is connected to the microcontroller, and the analog-to-digital converter and the microcontroller can process these sampled voltages, for example, compare the sampled voltage data with the corresponding voltage threshold data, and determine the insulation state of the insulation resistance of the load according to the comparison result of the sampled voltage data and the corresponding voltage threshold data.

[0067] Reference below Figure 4 An insulation detection method according to an embodiment of the present invention is described.

[0068] Figure 4 FIG. 1 is a flow chart of an insulation detection method according to an embodiment of the present invention. Figure 4 As shown, the insulation detection method at least includes steps S1 to S3.

[0069] Step S1, obtaining first sampled voltage data sampled at a first sampling point within a preset sampling period and second sampled voltage data sampled at a second voltage sampling point within a preset sampling period when the first power source is supplied, and obtaining third sampled voltage data sampled at the first sampling point within a preset sampling period and fourth sampled voltage data sampled at the second voltage sampling point within a preset sampling period when the second power source is supplied.

[0070] Among them, Figure 5As shown, the preset sampling period can be understood as a plurality of sampling moments from the end to the beginning of the sampling time within the sampling period. For example, when the sampling is about to end, the last one-tenth of the sampling period is selected as the preset sampling period of the sampling data, and as shown in FIG. Figure 5 As shown, as the sampling time increases, the sampled voltage gradually tends to be stable. Therefore, obtaining relatively stable voltage data within a preset sampling period can improve the accuracy of insulation detection.

[0071] In an embodiment, when performing voltage sampling, the first power supply and the second power supply can switch with each other, and the voltages provided by the first power supply and the second power supply are different. For example, the first power supply provides a 48V voltage and the second power supply provides a 24V voltage. During the switching process between the first power supply and the second power supply, a stable sampling voltage can be obtained through dynamic adjustment of the power supply.

[0072] For example, when powered by the first power supply, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second voltage data sampled by the second sampling point within the preset sampling period can be obtained. When powered by the second power supply, the third sampled voltage data of the first sampling point within the preset sampling period and the fourth sampled voltage data of the second sampling point within the preset sampling period can be obtained. In this way, four sampled voltage data can be obtained, and these sampled voltage data are used as the data basis for insulation status detection. For example, the four sampled voltage data obtained are relatively stable. When the insulation status detection is performed based on these sampled voltage data, the stability and accuracy of the insulation status detection can also be improved.

[0073] Step S2, obtaining first voltage threshold data corresponding to the first sampled voltage data, obtaining second voltage threshold data corresponding to the second sampled voltage data, obtaining third voltage threshold data corresponding to the third sampled voltage data, and obtaining fourth voltage threshold data corresponding to the fourth sampled voltage data.

[0074] In an embodiment, the voltage threshold data corresponding to each sampled voltage data is obtained, and the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data can be used as the data basis for judging the insulation state of the insulation resistance of the load to improve the accuracy of insulation detection.

[0075] Step S3, determining the insulation state of the load based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state.

[0076] In an embodiment, the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, the first sampled voltage data is compared with the first voltage threshold data, the second sampled voltage data is compared with the second voltage threshold data, the third sampled voltage data is compared with the third voltage threshold data, and the fourth sampled voltage data is compared with the fourth voltage threshold data. The insulation state of the load is determined according to the comparison result of the first sampled voltage data and the first voltage threshold data, the comparison result of the second sampled voltage data and the second voltage threshold data, the comparison result of the third sampled voltage data and the third voltage threshold data, and the comparison result of the fourth sampled voltage data and the fourth voltage threshold data. This can avoid misjudgment of the insulation failure state, reduce the probability of insulation alarm, and thus improve the accuracy of insulation detection.

[0077] Therefore, in an embodiment of the present invention, when the power is supplied by the first power source, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. When the power is switched to the second power source, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data. In this way, the stability of the voltage data may be effectively avoided due to the interference of the insulation resistance of the single grounding terminal, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0078] In one embodiment of the present invention, the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state, including: when the first sampled voltage data is greater than the first voltage threshold data, and the second sampled voltage data is greater than the second voltage threshold data, and the third sampled voltage data is greater than the third voltage threshold data, and the fourth sampled voltage data is greater than the fourth voltage threshold data, the insulation state of the load is determined to be the insulation normal state, otherwise, the insulation state of the load is determined to be the insulation failure state.

[0079] In an embodiment, when the first sampled voltage data is greater than the first voltage threshold data, the second sampled voltage data is greater than the second voltage threshold data, the third sampled voltage data is greater than the third voltage threshold data, and the fourth sampled voltage data is greater than the fourth voltage threshold data, the insulation state of the load is determined to be a normal insulation state.

[0080] For example, when the four sampled voltage data are all greater than the corresponding voltage threshold data, a preset resistance value within the standard insulation resistance range corresponding to the load will be output, that is, the preset resistance value will replace the previous insulation resistance value. Just as, when the insulation resistance value is greater than the preset alarm threshold, the insulation state of the load is a normal insulation state. Therefore, when the four sampled voltage data are all greater than the corresponding voltage threshold data, the output preset resistance value is greater than the preset alarm threshold, so that the insulation state of the load can be directly determined to be a normal insulation state.

[0081] If the first sampled voltage data is greater than the first voltage threshold data, the second sampled voltage data is greater than the second voltage threshold data, the third sampled voltage data is greater than the third voltage threshold data, and the fourth sampled voltage data is greater than the fourth voltage threshold data cannot be simultaneously satisfied, then it is determined that the insulation state of the load is an insulation failure state.

[0082] For example, when at least one of the four sampled voltage data is not greater than the corresponding voltage threshold data, the resistance value of the insulation resistance will be output. The resistance value of the insulation resistance is the value initially compared with the preset alarm threshold, that is, when the resistance value of the insulation resistance is less than the preset alarm threshold, the insulation state of the load is an insulation failure state. Therefore, when the condition that at least one of the above four sampled voltage data is not greater than the corresponding voltage threshold data is met, the output insulation resistance value is still less than the preset alarm threshold, so that the insulation state of the load can be directly determined to be an insulation failure state.

[0083] Specifically, please refer to Figure 6The flowchart of determining the insulation state of a load is shown, and the process at least includes steps S11 to S17.

[0084] Step S11, start.

[0085] Step S12, obtaining first sampled voltage data, second sampled voltage data, third sampled voltage data and fourth sampled voltage data.

[0086] Step S13, acquiring first voltage threshold data, second voltage threshold data, third voltage threshold data and fourth voltage threshold data.

[0087] Step S14, determine whether the first sampled voltage data is greater than the first voltage threshold data, whether the second sampled voltage data is greater than the second voltage threshold data, whether the third sampled voltage data is greater than the third voltage threshold data, and whether the fourth sampled voltage data is greater than the fourth voltage threshold data. If so, execute step S15, if not, execute step S16.

[0088] Step S15, determining that the load is in a normal insulation state.

[0089] Step S16, determining that the load is in an insulation failure state.

[0090] Step S17, end.

[0091] Therefore, based on the comparison results of the four sampled voltage data and their corresponding voltage threshold data, it is possible to directly determine whether the insulation state of the load is a normal insulation state or an insulation failure state, which can prevent misjudgment under large resistance conditions when the insulation resistance value is compared with the preset alarm threshold, reduce the probability of false insulation alarm under large resistance conditions, and improve the accuracy and reliability of insulation state detection.

[0092] In one embodiment of the present invention, the preset sampling period includes multiple sampling moments from back to front according to the sampling time; the first sampled voltage data is obtained by the average value of multiple voltage data correspondingly sampled at multiple sampling moments by the first sampling point when the first power supply is supplied; the second sampled voltage data is obtained by the average value of multiple voltage data correspondingly sampled at multiple sampling moments by the second sampling point when the first power supply is supplied; the third sampled voltage data is obtained by the average value of multiple voltage data correspondingly sampled at multiple sampling moments by the first sampling point when the second power supply is supplied; the fourth sampled voltage data is obtained by the average value of multiple voltage data correspondingly sampled at multiple sampling moments by the second sampling point when the second power supply is supplied.

[0093] In an embodiment, Figure 5As shown, the preset sampling period is a plurality of sampling moments from the end to the end according to the sampling time, for example, the two sampling moments at the end are selected. As the sampling time goes by, the voltage data also tends to be stable. Therefore, the voltage data corresponding to the two sampling moments at the end are selected to obtain the sampled voltage data, which can improve the stability and accuracy of the sampled voltage data.

[0094] For example, when the first power supply is used, two sampling moments are selected from the back to the front according to the sampling time, and two voltage data corresponding to the first sampling point A at these two sampling moments are obtained, for example, recorded as C1 and C2, and then the average value of the two voltage data is calculated. The calculated average value is the first sampled voltage data and is recorded as C, that is, C=(C1+C2) / 2.

[0095] When the first power supply is used, two sampling moments are selected from the back to the front according to the sampling time, and two voltage data corresponding to the second sampling point B at these two sampling moments are obtained, for example, recorded as D1 and D2, and then the average value of the two voltage data is calculated. The calculated average value is the second sampled voltage data and is recorded as D, that is, D=(D1+D2) / 2.

[0096] When the second power supply is used, two sampling moments are selected from the back to the front according to the sampling time, and two voltage data corresponding to the first sampling point A at these two sampling moments are obtained, for example, recorded as E1 and E2, and then the average value of the two voltage data is calculated. The calculated average value is the third sampling voltage data and is recorded as E, that is, E=(E1+E2) / 2.

[0097] When the second power supply is used, two sampling moments are selected from the back to the front according to the sampling time, and two voltage data corresponding to the second sampling point B at these two sampling moments are obtained, for example, recorded as F1 and F2, and then the average value of the two voltage data is calculated. The calculated average value is the fourth sampling voltage data and is recorded as F, that is, F=(F1+F2) / 2.

[0098] Therefore, if Figure 5 As shown, as the sampling time goes by, the voltage data tends to be stable. At least two sampling moments are selected from the back to the front according to the sampling time. Stable voltage data can be obtained at the sampling moments, and the single voltage data can be prevented from being interfered with and causing the data to be invalid, thereby reducing the impact of invalid data on the sampled voltage data, improving the accuracy and reliability of the sampled voltage data acquisition, and further improving the accuracy and reliability of insulation detection.

[0099] In one embodiment of the present invention, obtaining first voltage threshold data corresponding to first sampled voltage data, and obtaining second voltage threshold data corresponding to second sampled voltage data, include: when a first reference resistor is used as an insulation resistor and the power is supplied by a first power supply, obtaining a first reference voltage corresponding to a first sampling point at a preset sampling time and a second reference voltage corresponding to a second sampling point at a preset sampling time; when a second reference resistor is used as an insulation resistor and the power is supplied by a first power supply, obtaining a third reference voltage corresponding to the first sampling point at a preset sampling time and a fourth reference voltage corresponding to the second sampling point at a preset sampling time, wherein the resistance value of the first reference resistor is less than the resistance value of the second reference resistor; determining the first voltage threshold data according to the first reference voltage and the third reference voltage, and determining the second voltage threshold data according to the second reference voltage and the fourth reference voltage.

[0100] The preset sampling time is the last sampling time in the current sampling cycle, such as Figure 7 As shown, as the sampling time goes by, the reference voltage is also tending to be stable. Therefore, the last sampling moment in the sampling cycle is selected as the preset sampling moment. The preset sampling moment is the sampling moment when the voltage tends to be stable. Then, a stable reference voltage can be obtained at the preset sampling moment.

[0101] In an embodiment, for example, the first reference resistor is recorded as Rlowref, and the second reference resistor is recorded as Rhighref. The resistance of the first reference resistor Rlowref is less than the resistance of the second reference resistor Rhighref. The resistance of the first reference resistor Rlowref includes, but is not limited to, 250KΩ, and the resistance of the second reference resistor Rhighref includes, but is not limited to, 1.5MΩ. The resistance of the first reference resistor Rlowref is related to the selected voltage platform, and the voltage platform includes, for example, 500V, 1000V, and 1500V. For example, if the current voltage platform is 500V, and the accuracy requirement boundary threshold is 500V / Ω, then the product of the current voltage platform 500V and the accuracy requirement boundary threshold 500V / Ω is the resistance of the first reference resistor Rlowref, that is, the resistance of the first reference resistor Rlowref is 250KΩ.

[0102] Specifically, when obtaining the first voltage threshold data corresponding to the first sampled voltage data, when the first power supply is used, the first reference resistor Rlowref is used as the insulation resistor, the first reference voltage corresponding to the first sampling point A at the preset sampling time is obtained, and then the second reference resistor Rhighref is used as the insulation resistor to obtain the third reference voltage corresponding to the first sampling point A at the preset sampling time. Figure 8As shown, when the first power supply is supplied, there is an obvious voltage difference between the sampling voltages of the first reference resistor Rlowref and the second reference resistor Rhighref. Therefore, after obtaining the first reference resistor and the third reference resistor, a weighted operation is used to determine the first voltage threshold data based on the voltage difference between the first reference resistor and the third reference resistor.

[0103] When obtaining the second voltage threshold data corresponding to the second sampled voltage data, when the first power supply is supplied, the first reference resistor Rlowref is used as the insulation resistance, the second reference voltage corresponding to the second sampling point B at the preset sampling time is obtained, and then the second reference resistor Rhighref is used as the insulation resistance to obtain the fourth reference voltage corresponding to the second sampling point B at the preset sampling time, and then the second voltage threshold data is determined by a weighted operation based on the voltage difference between the second reference resistor and the fourth reference resistor.

[0104] Combination Figure 7 and Figure 8 As shown, as the sampling time increases, the voltage gradually tends to be stable. By using the reference voltage at the sampling moment in the relatively stable stage to determine the voltage threshold data, the acquired voltage threshold data can also be relatively stable, thereby improving the stability of insulation detection. In addition, when the first power supply is used, the voltage difference of the reference voltage acquired by different reference resistors at the sampling point is used to determine the first voltage threshold data and the second voltage threshold data, which can improve the accuracy of determining the first voltage threshold data and the second voltage threshold data.

[0105] In one embodiment of the present invention, first voltage threshold data is determined based on a first reference voltage and a third reference voltage, and second voltage threshold data is determined based on a second reference voltage and a fourth reference voltage, including: performing weighted operations on the first reference voltage and the third reference voltage respectively and summing them up to obtain the first voltage threshold data, wherein the weight coefficients corresponding to the first reference voltage and the third reference voltage are respectively preset; performing weighted operations on the second reference voltage and the fourth reference voltage respectively and summing them up to obtain the second voltage threshold data, wherein the weight coefficients corresponding to the second reference voltage and the fourth reference voltage are respectively preset.

[0106] In an embodiment, when the first voltage threshold data is determined according to the first reference voltage and the third reference voltage, for example, the first reference voltage is recorded as V1 and the third reference voltage is recorded as V3. Figure 8As shown, since there is an obvious voltage difference between the first reference voltage V1 and the third reference voltage V3, the voltage difference between the first reference voltage V1 and the third reference voltage V3 can be used, and then the weight coefficients corresponding to the first reference voltage V1 and the third reference voltage V3 are pre-set, the weight coefficient corresponding to the first reference voltage V1 is, for example, 0.3, and the weight coefficient corresponding to the third reference voltage V3 is, for example, 0.7. The first reference voltage V1 and the third reference voltage V3 are weighted, respectively. The data are then summed to obtain the first voltage threshold data, for example, denoted as Va, that is, Va=0.3*V1+0.7*V3.

[0107] When the second voltage threshold data is determined according to the second reference voltage and the fourth reference voltage, for example, the second reference voltage is recorded as V2, and the fourth reference voltage is recorded as V4. Figure 8 As shown, since there is an obvious voltage difference between the second reference voltage V2 and the fourth reference voltage V4, the voltage difference between the second reference voltage V2 and the fourth reference voltage V4 can be used, and then through the pre-set weight coefficients corresponding to the second reference voltage V2 and the fourth reference voltage V4, the weight coefficient corresponding to the second reference voltage V2 is, for example, 0.3, and the weight coefficient corresponding to the fourth reference voltage V4 is, for example, 0.7, weighted operations are performed on the second reference voltage V2 and the fourth reference voltage V4 respectively, and then the sum is obtained to obtain the second voltage threshold data, for example, recorded as Vb, that is, Vb=0.3*V2+0.7*V4.

[0108] Therefore, the voltage difference between the reference voltages obtained at the same sampling point when different reference resistors are powered by the same power supply can be used to calculate the first voltage threshold data Va and the second voltage threshold data Vb using a weighted algorithm, thereby improving the accuracy of obtaining the first voltage threshold data Va and the second voltage threshold data Vb and further improving the accuracy and reliability of insulation detection.

[0109] In one embodiment of the present invention, obtaining third voltage threshold data corresponding to the third sampled voltage data, and obtaining fourth voltage threshold data corresponding to the fourth sampled voltage data, include: when the first reference resistor is used as the insulation resistor and the power is supplied by the second power supply, obtaining a fifth reference voltage corresponding to the first sampling point at a preset sampling time and a sixth reference voltage corresponding to the second sampling point at a preset sampling time; when the second reference resistor is used as the insulation resistor and the power is supplied by the second power supply, obtaining a seventh reference voltage corresponding to the first sampling point at a preset sampling time and an eighth reference voltage corresponding to the second sampling point at a preset sampling time, wherein the resistance value of the first reference resistor is less than the resistance value of the second reference resistor; determining the third voltage threshold data according to the fifth reference voltage and the seventh reference voltage, and determining the fourth voltage threshold data according to the sixth reference voltage and the eighth reference voltage.

[0110] In an embodiment, when obtaining the third voltage threshold data corresponding to the third sampling voltage data, when the second power supply is used, the first reference resistor Rlowref is used as the insulation resistor, the fifth reference voltage corresponding to the first sampling point A at the preset sampling time is obtained, and then the second reference resistor Rhighref is used as the insulation resistor to obtain the seventh reference voltage corresponding to the first sampling point A at the preset sampling time. Figure 8 As shown, when the second power supply is used, there is an obvious voltage difference between the sampling voltages of the first reference resistor Rlowref and the second reference resistor Rhighref. Therefore, after obtaining the fifth reference resistor and the seventh reference resistor, a weighted operation is used to determine the third voltage threshold data based on the voltage difference between the fifth reference resistor and the seventh reference resistor.

[0111] When obtaining the fourth voltage threshold data corresponding to the fourth sampling voltage data, when the second power supply is used, the first reference resistor Rlowref is used as the insulation resistance, the sixth reference voltage corresponding to the second sampling point B at the preset sampling time is obtained, and then the second reference resistor Rhighref is used as the insulation resistance to obtain the eighth reference voltage corresponding to the second sampling point B at the preset sampling time, and then the fourth voltage threshold data is determined by weighted operation based on the voltage difference between the sixth reference resistor and the eighth reference resistor.

[0112] Combination Figure 7 and Figure 8 As shown, as the sampling time increases, the voltage gradually tends to be stable. By using the reference voltage at the sampling moment in the relatively stable stage to determine the voltage threshold data, the acquired voltage threshold data can also be relatively stable, thereby improving the stability of insulation detection. In addition, when the second power supply is used, the voltage difference of the reference voltage acquired by different reference resistors at the sampling point is used to determine the third voltage threshold data and the fourth voltage threshold data, which can improve the accuracy of the determination of the third voltage threshold data and the fourth voltage threshold data.

[0113] In one embodiment of the present invention, third voltage threshold data is determined based on a fifth reference voltage and a seventh reference voltage, and fourth voltage threshold data is determined based on a sixth reference voltage and an eighth reference voltage, including: performing weighted operations on the fifth reference voltage and the seventh reference voltage and summing them up to obtain the third voltage threshold data, wherein the weight coefficients corresponding to the fifth reference voltage and the seventh reference voltage are respectively preset; performing weighted operations on the sixth reference voltage and the eighth reference voltage and summing them up to obtain the fourth voltage threshold data, wherein the weight coefficients corresponding to the sixth reference voltage and the eighth reference voltage are respectively preset.

[0114] In an embodiment, when the first voltage threshold data is determined according to the fifth reference voltage and the seventh reference voltage, for example, the fifth reference voltage is recorded as V5 and the seventh reference voltage is recorded as V7. Figure 8 As shown, since there is an obvious voltage difference between the fifth reference voltage V5 and the seventh reference voltage V7, the voltage difference between the fifth reference voltage V5 and the seventh reference voltage V7 can be used, and then the weight coefficients corresponding to the fifth reference voltage V5 and the seventh reference voltage V7 are preset, respectively. The weight coefficient corresponding to the fifth reference voltage V5 is, for example, 0.3, and the weight coefficient corresponding to the seventh reference voltage V7 is, for example, 0.7. The fifth reference voltage V5 and the seventh reference voltage V7 are weighted, respectively, and then the sum is obtained to obtain the third voltage threshold data, for example, recorded as Vc, that is, Vc=0.3*V5+0.7*V7.

[0115] When the fourth voltage threshold data is determined according to the sixth reference voltage and the eighth reference voltage, for example, the sixth reference voltage is recorded as V6 and the eighth reference voltage is recorded as V8. Figure 8 As shown, since there is an obvious voltage difference between the sixth reference voltage V6 and the eighth reference voltage V8, the voltage difference between the sixth reference voltage V6 and the eighth reference voltage V8 can be used, and then the weight coefficients corresponding to the sixth reference voltage V6 and the eighth reference voltage V8 are preset, respectively. The weight coefficient corresponding to the sixth reference voltage V6 is, for example, 0.3, and the weight coefficient corresponding to the eighth reference voltage V8 is, for example, 0.7. The sixth reference voltage V6 and the eighth reference voltage V8 are weighted, respectively. Then the sum is summed to obtain the fourth voltage threshold data, for example, recorded as Vd, that is, Vd=0.3*V6+0.7*V8.

[0116] Therefore, based on the voltage difference between the reference voltages obtained at the same sampling point when different reference resistors are powered by the same power supply, a weighted algorithm can be used to calculate the third voltage threshold data Vc and the fourth voltage threshold data Vd, thereby improving the accuracy of obtaining the third voltage threshold data Vc and the fourth voltage threshold data Vd and further improving the accuracy and reliability of insulation detection.

[0117] In one embodiment of the present invention, the preset sampling moment is the last sampling moment in the current sampling cycle.

[0118] In an embodiment, Figure 7 As shown, during the sampling process, as the sampling time increases, the reference voltage tends to be stable. Therefore, the preset sampling moment is the last sampling moment in the current sampling cycle, and the reference voltage obtained at the preset sampling moment is a stable voltage. Using a stable reference voltage to calculate the voltage threshold data can also improve the accuracy and stability of the voltage threshold data calculation, thereby improving the stability and accuracy of insulation detection.

[0119] In one embodiment of the present invention, before obtaining the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the first power supply is supplied, and obtaining the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the second power supply is supplied, it also includes: judging whether the resistance value of the insulation resistance is less than a preset alarm threshold; if so, executing the steps of obtaining the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the first power supply is supplied, and obtaining the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the second power supply is supplied, otherwise, determining that the load is in a normal insulation state.

[0120] In an embodiment, before obtaining the first sampled voltage data, the first voltage threshold data, the second sampled voltage data and the second voltage threshold data, it is necessary to further compare the insulation resistance of the load with the preset alarm threshold. If the insulation resistance of the load is greater than the preset alarm threshold, it means that the insulation resistance of the current load is within the standard insulation resistance range, indicating that the current insulation resistance value can be normally insulated. Therefore, the insulation state of the load can be directly determined based on the insulation resistance value, that is, it is determined that the current load is in a normal insulation state.

[0121] If the insulation resistance of the load is less than the preset alarm threshold, the steps of obtaining first sampled voltage data sampled by the first sampling point within the preset sampling period and second sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the first power supply is supplied, and obtaining third sampled voltage data sampled by the first sampling point within the preset sampling period and fourth sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the second power supply is supplied are further performed, so as to determine the insulation resistance of the load again according to the voltage threshold data corresponding to each sampled voltage data obtained, that is, to correct the insulation resistance value initially obtained, and determine the insulation state of the load according to the corrected resistance value, so as to avoid misjudging the normal insulation state as the insulation failure state under the condition of large resistance value, and reduce the probability of erroneously reporting the insulation warning, so as to distinguish whether the current insulation resistance value is in a real insulation failure state based on the corrected resistance value, thereby improving the accuracy of insulation state detection.

[0122] According to the insulation detection method of the embodiment of the present invention, when the power is supplied by the first power supply, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. When the power is switched to the second power supply, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data. In this way, the stability of the voltage data may be affected by the interference of the insulation resistance of the single grounding terminal, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0123] A further embodiment of the present invention also discloses an insulation detection device, which is used for an insulation detection circuit. The insulation detection circuit includes a power supply module, a first sampling point, a second sampling point and an insulation resistor, wherein the power supply module can provide a first power supply or a second power supply, the voltages output by the first power supply and the second power supply are different, the first sampling point is connected to the positive terminal of the power supply module, the first sampling point is also connected to the first ground terminal and one end of the insulation resistor through a first resistor, the second sampling point is respectively connected to the second ground terminal and the negative terminal of the power supply module through a second resistor, the second sampling point is also connected to the first sampling point through a third resistor, and the negative terminal of the power supply module is also connected to the second ground terminal and the other end of the insulation resistor through a fourth resistor.

[0124] like Fig. 9 As shown, the insulation detection device 2 includes: a first acquisition module 21 , a second acquisition module 22 and a determination module 23 .

[0125] Among them, the first acquisition module 21 is used to obtain the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the first power supply is supplied, and to obtain the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the second power supply is supplied; the second acquisition module 22 is used to obtain the first voltage threshold data corresponding to the first sampled voltage data, and to obtain the second voltage threshold data corresponding to the second sampled voltage data, and to obtain the third voltage threshold data corresponding to the third sampled voltage data, and to obtain the fourth voltage threshold data corresponding to the fourth sampled voltage data; the determination module 23 is used to determine the insulation state of the load based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and a normal insulation state.

[0126] In one embodiment of the present invention, the determination module 23 determines the insulation state of the load based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state, including: when the first sampled voltage data is greater than the first voltage threshold data, and the second sampled voltage data is greater than the second voltage threshold data, and the third sampled voltage data is greater than the third voltage threshold data, and the fourth sampled voltage data is greater than the fourth voltage threshold data, the insulation state of the load is determined to be the insulation normal state, otherwise, the insulation state of the load is determined to be the insulation failure state.

[0127] In one embodiment of the present invention, the preset sampling period includes multiple sampling moments from back to front according to the sampling time; the first sampled voltage data is obtained by the average value of multiple voltage data correspondingly sampled at multiple sampling moments by the first sampling point when the first power supply is supplied; the second sampled voltage data is obtained by the average value of multiple voltage data correspondingly sampled at multiple sampling moments by the second sampling point when the first power supply is supplied; the third sampled voltage data is obtained by the average value of multiple voltage data correspondingly sampled at multiple sampling moments by the first sampling point when the second power supply is supplied; the fourth sampled voltage data is obtained by the average value of multiple voltage data correspondingly sampled at multiple sampling moments by the second sampling point when the second power supply is supplied.

[0128] In one embodiment of the present invention, the second acquisition module 22 acquires first voltage threshold data corresponding to the first sampled voltage data, and acquires second voltage threshold data corresponding to the second sampled voltage data, including: when the first reference resistor is used as the insulation resistor and the power is supplied by the first power supply, acquiring the first reference voltage corresponding to the first sampling point at the preset sampling time and the second reference voltage corresponding to the second sampling point at the preset sampling time; when the second reference resistor is used as the insulation resistor and the power is supplied by the first power supply, acquiring the third reference voltage corresponding to the first sampling point at the preset sampling time and the fourth reference voltage corresponding to the second sampling point at the preset sampling time, wherein the resistance value of the first reference resistor is less than the resistance value of the second reference resistor; determining the first voltage threshold data according to the first reference voltage and the third reference voltage, and determining the second voltage threshold data according to the second reference voltage and the fourth reference voltage.

[0129] In one embodiment of the present invention, the acquisition module 22 determines the first voltage threshold data according to the first reference voltage and the third reference voltage, and determines the second voltage threshold data according to the second reference voltage and the fourth reference voltage, including: performing weighted operations on the first reference voltage and the third reference voltage respectively and summing them up to obtain the first voltage threshold data, wherein the weight coefficients corresponding to the first reference voltage and the third reference voltage are respectively preset; performing weighted operations on the second reference voltage and the fourth reference voltage respectively and summing them up to obtain the second voltage threshold data, wherein the weight coefficients corresponding to the second reference voltage and the fourth reference voltage are respectively preset.

[0130] In one embodiment of the present invention, the second acquisition module 22 acquires the third voltage threshold data corresponding to the third sampled voltage data, and acquires the fourth voltage threshold data corresponding to the fourth sampled voltage data, including: when the first reference resistor is used as the insulation resistor and the power is supplied by the second power supply, acquiring the fifth reference voltage corresponding to the first sampling point at the preset sampling time and the sixth reference voltage corresponding to the second sampling point at the preset sampling time; when the second reference resistor is used as the insulation resistor and the power is supplied by the second power supply, acquiring the seventh reference voltage corresponding to the first sampling point at the preset sampling time and the eighth reference voltage corresponding to the second sampling point at the preset sampling time, wherein the resistance value of the first reference resistor is less than the resistance value of the second reference resistor; determining the third voltage threshold data according to the fifth reference voltage and the seventh reference voltage, and determining the fourth voltage threshold data according to the sixth reference voltage and the eighth reference voltage.

[0131] In one embodiment of the present invention, the second acquisition module 22 determines the third voltage threshold data based on the fifth reference voltage and the seventh reference voltage, and determines the fourth voltage threshold data based on the sixth reference voltage and the eighth reference voltage, including: performing weighted operations on the fifth reference voltage and the seventh reference voltage and summing them up to obtain the third voltage threshold data, wherein the weight coefficients corresponding to the fifth reference voltage and the seventh reference voltage are respectively preset; performing weighted operations on the sixth reference voltage and the eighth reference voltage and summing them up to obtain the fourth voltage threshold data, wherein the weight coefficients corresponding to the sixth reference voltage and the eighth reference voltage are respectively preset.

[0132] In one embodiment of the present invention, the preset sampling moment is the last sampling moment in the current sampling cycle.

[0133] In one embodiment of the present invention, before obtaining the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the first power supply is supplied, and obtaining the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the second power supply is supplied, the first acquisition module 21 is further used to: determine whether the resistance value of the insulation resistance is less than a preset alarm threshold; if so, execute the steps of obtaining the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the first power supply is supplied, and obtaining the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the second power supply is supplied; otherwise, determine that the load is in a normal insulation state.

[0134] According to the insulation detection device 2 of the embodiment of the present invention, when powered by the first power supply, the first acquisition module 21 acquires the first sampled voltage data sampled at the first sampling point within the preset sampling period and the second sampled voltage data sampled at the second sampling point within the preset sampling period. When switched to the second power supply, the third sampled voltage data sampled at the first sampling point within the preset sampling period and the fourth sampled voltage data sampled at the second sampling point within the preset sampling period are acquired. Since the preset sampling period is a period when the sampling voltage tends to be stable, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data acquired within the preset sampling period are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then the second acquisition module 22 also needs to obtain the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data. The determination module 23 determines the insulation state of the load based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, determines whether the load is in a normal insulation state or an insulation failure state, can distinguish the actual insulation failure state, avoids the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0135] A further embodiment of the present invention also discloses an insulation detection device.

[0136] In some embodiments, the insulation detection equipment includes the insulation detection device 2 described in the above embodiments of the present invention.

[0137] In other embodiments, the insulation detection device includes a processor, a memory, and an insulation detection program stored in the memory and executable on the processor. When the insulation detection program is executed by the processor, the insulation detection method described in the above embodiment of the present invention is implemented.

[0138] According to the insulation detection device of the embodiment of the present invention, when powered by the first power supply, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. When switched to the second power supply, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data, which can effectively avoid the single grounding terminal from affecting the stability of the voltage data due to the interference of the insulation resistance, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0139] A further embodiment of the present invention also discloses a battery management controller, comprising the insulation detection device described in the above embodiment of the present invention, or a processor, a memory, and an insulation detection program stored in the memory and executable on the processor, wherein when the insulation detection program is executed by the processor, the insulation detection method described in the above embodiment of the present invention is implemented.

[0140] According to the battery management controller of the embodiment of the present invention, when powered by the first power source, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. When switched to the second power source for power supply, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data, which can effectively avoid the single grounding terminal possibly affecting the stability of the voltage data due to the interference of the insulation resistance, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0141] A further embodiment of the present invention also discloses a computer-readable storage medium, on which an insulation detection program is stored. When the insulation detection program is executed by a processor, the insulation detection method described in the above embodiment of the present invention is implemented.

[0142] According to the computer-readable storage medium of the embodiment of the present invention, when the insulation detection program stored thereon is executed by the processor, when the power is supplied by the first power source, the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second sampling point within the preset sampling period are obtained, and when the power is switched to the second power source, the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second sampling point within the preset sampling period are obtained. In this sampling process, the first grounding terminal and the second grounding terminal are used to obtain the voltage data of the first sampling point and the second sampling point, and the voltage data within the preset sampling period is selected as the sampled voltage data, so that the single grounding terminal may effectively avoid the influence of the stability of the voltage data due to the interference of the insulation resistance, and the preset sampling period is a period when the sampled voltage tends to be stable. Therefore, the first sampled voltage data, the second sampled voltage data, the third sampled voltage data and the fourth sampled voltage data obtained within the preset sampling period by using the first grounding segment and the second grounding terminal are also relatively stable, thereby improving the stability and reliability of the acquisition of the sampled voltage data. Then, the first voltage threshold data corresponding to the first sampled voltage data and the second voltage threshold data corresponding to the second sampled voltage data, as well as the third voltage threshold data corresponding to the third sampled voltage data and the fourth voltage threshold data corresponding to the fourth sampled voltage data are obtained, and the insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, that is, it is judged whether the load is in a normal insulation state or an insulation failure state, and the real insulation failure state can be distinguished to avoid the situation where the normal insulation state is misjudged as an insulation failure state, thereby reducing the probability of insulation alarm and improving the accuracy of insulation state detection and the stability of insulation detection.

[0143] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0144] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An insulation detection method, characterized in that: For an insulation detection circuit, the insulation detection circuit includes a power supply module, a first sampling point, a second sampling point and an insulation resistor, wherein the power supply module can provide a first power supply or a second power supply, the first power supply and the second power supply output voltages are different, the first sampling point is connected to the positive terminal of the power supply module, the first sampling point is also connected to the first ground terminal and one end of the insulation resistor through a first resistor, the second sampling point is respectively connected to the second ground terminal and the negative terminal of the power supply module through a second resistor, the second sampling point is also connected to the first sampling point through a third resistor, the negative terminal of the power supply module is also connected to the second ground terminal and the other end of the insulation resistor through a fourth resistor, and the insulation detection method includes: acquiring first sampled voltage data sampled at the first sampling point within a preset sampling period and second sampled voltage data sampled at the second voltage sampling point within a preset sampling period when the first power source is supplied, and acquiring third sampled voltage data sampled at the first sampling point within a preset sampling period and fourth sampled voltage data sampled at the second voltage sampling point within a preset sampling period when the second power source is supplied; Acquire first voltage threshold data corresponding to the first sampled voltage data, acquire second voltage threshold data corresponding to the second sampled voltage data, acquire third voltage threshold data corresponding to the third sampled voltage data, and acquire fourth voltage threshold data corresponding to the fourth sampled voltage data; The insulation state of the load is determined based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state.

2. The insulation detection method according to claim 1, characterized in that: The step of determining the insulation state of the load based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data, and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state, comprises: When the first sampling voltage data is greater than the first voltage threshold data, the second sampling voltage data is greater than the second voltage threshold data, the third sampling voltage data is greater than the third voltage threshold data, and the fourth sampling voltage data is greater than the fourth voltage threshold data, it is determined that the insulation state of the load is a normal insulation state; otherwise, it is determined that the insulation state of the load is an insulation failure state.

3. The insulation detection method according to claim 1, characterized in that: The preset sampling period includes a plurality of sampling moments from the back to the front according to the sampling time; The first sampled voltage data is obtained by averaging a plurality of voltage data correspondingly sampled at a plurality of sampling moments at the first sampling point when the first power supply is powered; The second sampled voltage data is obtained by averaging a plurality of voltage data correspondingly sampled at a plurality of sampling moments at the second sampling point when the first power supply is supplying power; The third sampled voltage data is obtained by averaging a plurality of voltage data correspondingly sampled at the first sampling point at a plurality of sampling moments when the second power supply is supplying power; The fourth sampled voltage data is obtained by averaging a plurality of voltage data correspondingly sampled at a plurality of sampling moments by the second sampling point when the second power supply is supplying power.

4. The insulation detection method according to claim 1, characterized in that: The obtaining of first voltage threshold data corresponding to the first sampled voltage data, and the obtaining of second voltage threshold data corresponding to the second sampled voltage data, include: When a first reference resistor is used as the insulation resistor and the first power supply is used for power supply, a first reference voltage corresponding to the first sampling point at a preset sampling time and a second reference voltage corresponding to the second sampling point at the preset sampling time are obtained; When a second reference resistor is used as the insulation resistor and the first power supply is used for power supply, a third reference voltage corresponding to the first sampling point at the preset sampling time and a fourth reference voltage corresponding to the second sampling point at the preset sampling time are obtained, wherein the resistance value of the first reference resistor is less than the resistance value of the second reference resistor; The first voltage threshold data is determined according to the first reference voltage and the third reference voltage, and the second voltage threshold data is determined according to the second reference voltage and the fourth reference voltage.

5. The insulation detection method according to claim 4, characterized in that: The determining the first voltage threshold data according to the first reference voltage and the third reference voltage, and determining the second voltage threshold data according to the second reference voltage and the fourth reference voltage, comprises: Performing weighted operations on the first reference voltage and the third reference voltage respectively and summing them up to obtain the first voltage threshold data, wherein the weight coefficients corresponding to the first reference voltage and the third reference voltage are preset; The second voltage threshold data is obtained by performing weighted operations on the second reference voltage and the fourth reference voltage and then summing the sum of the sums. The weight coefficients corresponding to the second reference voltage and the fourth reference voltage are preset.

6. The insulation detection method according to claim 1, characterized in that: The obtaining of third voltage threshold data corresponding to the third sampled voltage data, and the obtaining of fourth voltage threshold data corresponding to the fourth sampled voltage data, include: When the first reference resistor is used as the insulation resistor and the second power supply is used for power supply, a fifth reference voltage corresponding to the first sampling point at a preset sampling time and a sixth reference voltage corresponding to the second sampling point at the preset sampling time are obtained; When a second reference resistor is used as the insulation resistor and the second power supply is used for power supply, a seventh reference voltage corresponding to the first sampling point at the preset sampling time and an eighth reference voltage corresponding to the second sampling point at the preset sampling time are obtained, wherein the resistance value of the first reference resistor is less than the resistance value of the second reference resistor; The third voltage threshold data is determined according to the fifth reference voltage and the seventh reference voltage, and the fourth voltage threshold data is determined according to the sixth reference voltage and the eighth reference voltage.

7. The insulation detection method according to claim 6, characterized in that: The determining the third voltage threshold data according to the fifth reference voltage and the seventh reference voltage, and determining the fourth voltage threshold data according to the sixth reference voltage and the eighth reference voltage, comprises: Performing weighted operations on the fifth reference voltage and the seventh reference voltage respectively and summing them up to obtain the third voltage threshold data, wherein the weight coefficients corresponding to the fifth reference voltage and the seventh reference voltage are respectively preset; The fourth voltage threshold data is obtained by performing weighted operations on the sixth reference voltage and the eighth reference voltage and then summing the sum of the sums. The weight coefficients corresponding to the sixth reference voltage and the eighth reference voltage are preset.

8. The insulation detection method according to any one of claims 4 to 7, characterized in that: The preset sampling time is the last sampling time in the current sampling cycle.

9. The insulation detection method according to any one of claims 1 to 7, characterized in that: Before the first sampled voltage data sampled at the first sampling point within a preset sampling period and the second sampled voltage data sampled at the second voltage sampling point within a preset sampling period when the first power supply is obtained, and before the third sampled voltage data sampled at the first sampling point within a preset sampling period and the fourth sampled voltage data sampled at the second voltage sampling point within a preset sampling period when the second power supply is obtained, the method further includes: Determining whether the insulation resistance is less than a preset alarm threshold; If so, the steps of obtaining the first sampled voltage data sampled by the first sampling point within the preset sampling period and the second sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the first power supply is supplied, and obtaining the third sampled voltage data sampled by the first sampling point within the preset sampling period and the fourth sampled voltage data sampled by the second voltage sampling point within the preset sampling period when the second power supply is supplied are performed; otherwise, it is determined that the load is in a normal insulation state.

10. An insulation detection device, characterized in that: Used for an insulation detection circuit, the insulation detection circuit includes a power supply module, a first sampling point, a second sampling point and an insulation resistor, wherein the power supply module can provide a first power supply or a second power supply, the first power supply and the second power supply output voltage are different, the first sampling point is connected to the positive terminal of the power supply module, the first sampling point is also connected to the first ground terminal and one end of the insulation resistor through a first resistor, the second sampling point is respectively connected to the second ground terminal and the negative terminal of the power supply module through a second resistor, the second sampling point is also connected to the first sampling point through a third resistor, the negative terminal of the power supply module is also connected to the second ground terminal and the other end of the insulation resistor through a fourth resistor, and the insulation detection device includes: a first acquisition module, configured to acquire first sampled voltage data sampled by the first sampling point within a preset sampling period and second sampled voltage data sampled by the second voltage sampling point within a preset sampling period when the first power source is supplying power, and to acquire third sampled voltage data sampled by the first sampling point within a preset sampling period and fourth sampled voltage data sampled by the second voltage sampling point within a preset sampling period when the second power source is supplying power; a second acquisition module, configured to acquire first voltage threshold data corresponding to the first sampled voltage data, acquire second voltage threshold data corresponding to the second sampled voltage data, acquire third voltage threshold data corresponding to the third sampled voltage data, and acquire fourth voltage threshold data corresponding to the fourth sampled voltage data; A determination module is used to determine the insulation state of the load based on the first sampled voltage data, the first voltage threshold data, the second sampled voltage data, the second voltage threshold data, the third sampled voltage data, the third voltage threshold data, the fourth sampled voltage data and the fourth voltage threshold data, wherein the insulation state includes an insulation failure state and an insulation normal state.

11. An insulation detection device, characterized in that: include: The insulation detection device according to claim 10; or, A processor, a memory, and an insulation detection program stored in the memory and executable on the processor, wherein the insulation detection program implements the insulation detection method according to any one of claims 1 to 9 when executed by the processor.

12. A battery management controller, characterized in that: include: The insulation testing device according to claim 11; or, A processor, a memory, and an insulation detection program stored in the memory and executable on the processor, wherein the insulation detection program implements the insulation detection method according to any one of claims 1 to 9 when executed by the processor.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores an insulation detection program, and when the insulation detection program is executed by the processor, the insulation detection method according to any one of claims 1 to 9 is implemented.

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