Insulation performance testing method, device, equipment, storage medium and program product

Abstract

The present application relates to an insulation performance detection method, device, equipment, storage medium and program product. The method includes: obtaining the electrode-to-ground voltage of the battery to be tested collected by the voltage sampling unit, obtaining the reference-to-ground voltage of the battery to be tested collected by the voltage sampling unit according to the sampling error information of the voltage sampling unit, and obtaining the positive electrode insulation resistance and negative electrode insulation resistance of the battery to be tested according to the current balance relationship expression between the positive and negative electrodes of the battery to be tested, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage and the reference-to-ground voltage, and determining the insulation performance detection result of the battery to be tested according to the positive electrode insulation resistance and the negative electrode insulation resistance; the electrode-to-ground voltage includes the positive electrode-to-ground voltage and the negative electrode-to-ground voltage. In the above method, the reference-to-ground voltage is determined based on the sampling error information of the voltage sampling unit, taking into account the influence of the sampling error information of the voltage sampling unit on the detection result, and correspondingly improving the accuracy of the insulation performance detection result.

Description

Technical Field

[0001] The present application relates to the technical field of battery detection, and in particular to an insulation performance detection method, device, equipment, storage medium and program product. Background Art

[0002] With the continuous development of new energy technologies, more and more devices use electricity as a power source.

[0003] Take new energy vehicles as an example. New energy vehicles use batteries as their power source, which have the characteristics of high voltage and high current. For high voltage and high current power batteries, it is very important to maintain good insulation performance. Based on this, in related technologies, it is usually necessary to test the insulation performance of the battery to determine whether the insulation performance of the battery meets the requirements.

[0004] However, the insulation performance detection of batteries in the related art has the problem of poor accuracy. Summary of the invention

[0005] Based on this, it is necessary to provide an insulation performance detection method, device, equipment, storage medium and program product to address the above technical problems.

[0006] In a first aspect, an embodiment of the present application provides an insulation performance detection method, the method comprising:

[0007] Acquire the electrode-to-ground voltage of the battery to be tested collected by the voltage sampling unit; the electrode-to-ground voltage includes the positive electrode-to-ground voltage and the negative electrode-to-ground voltage;

[0008] According to the sampling error information of the voltage sampling unit, a reference voltage to ground of the battery to be tested collected by the voltage sampling unit is obtained;

[0009] Obtain the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode voltage to ground, the negative electrode voltage to ground and the reference voltage to ground;

[0010] The insulation performance test result of the battery to be tested is determined based on the positive electrode insulation resistance value and the negative electrode insulation resistance value.

[0011] In an embodiment of the present application, during the insulation performance test, a reference voltage to ground is determined based on the sampling error information of the voltage sampling unit, so as to determine the insulation performance test result of the battery to be tested according to the positive electrode voltage to ground, the negative electrode voltage to ground and the reference voltage to ground, taking into account the influence of the sampling error information of the voltage sampling unit on the test result, and correspondingly improving the accuracy of the insulation performance test result, and the current balance relationship expression between the positive and negative electrodes of the battery to be tested can be used to accurately reflect the correlation between the positive electrode voltage to ground, the negative electrode voltage to ground, the reference voltage to ground, the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested, and the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested are determined based on the current balance relationship expression to determine the insulation performance test result of the battery to be tested, thereby improving the data comprehensiveness and accuracy of the test result.

[0012] In one embodiment, obtaining the electrode-to-ground voltage of the battery to be tested collected by the voltage sampling unit includes:

[0013] When the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are both in the on state, the positive electrode sampling unit in the control voltage sampling unit collects the positive electrode-to-ground voltage of the battery to be tested, and the negative electrode sampling unit in the control voltage sampling unit collects the negative electrode-to-ground voltage of the battery to be tested.

[0014] In the embodiment of the present application, when both the positive electrode measurement circuit and the negative electrode measurement circuit are in the on state, the positive electrode-to-ground voltage of the battery to be tested is collected by the positive electrode sampling unit, and the negative electrode-to-ground voltage of the battery to be tested is collected by the negative electrode sampling unit, so as to subsequently determine the insulation performance test result of the battery to be tested, thereby improving the comprehensiveness of the data and simultaneously improving the reliability of the insulation performance test result.

[0015] In one embodiment, obtaining the reference ground voltage of the battery to be tested collected by the voltage sampling unit according to the sampling error information of the voltage sampling unit includes:

[0016] Determine the target measurement circuit to be disconnected in the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested according to the sampling error information;

[0017] When the target measurement circuit is in a disconnected state, the voltage sampling unit is controlled to collect the reference ground voltage of the battery to be measured.

[0018] In an embodiment of the present application, a target measurement circuit to be disconnected is determined based on sampling error information to obtain the voltage to ground of a closed measurement circuit as a reference voltage to ground for subsequent determination of the insulation performance test result of the battery to be tested, thereby achieving a more accurate reference voltage to ground based on the sampling error information, and correspondingly improving the accuracy of the insulation performance test result determined based on the reference voltage to ground.

[0019] In one embodiment, the voltage sampling unit includes a positive electrode sampling unit and a negative electrode sampling unit; determining a target measurement circuit to be disconnected in a positive electrode measurement circuit and a negative electrode measurement circuit of a battery to be tested according to sampling error information includes:

[0020] Determine a reference ratio according to a first sampling error of the positive sampling unit and a second sampling error of the negative sampling unit in the sampling error information;

[0021] The target measurement circuit is determined based on the electrode-to-ground voltage and the reference ratio.

[0022] In an embodiment of the present application, based on the fact that the voltage sampling unit includes a positive sampling unit and a negative sampling unit, the target measurement circuit is simultaneously determined by the first sampling error of the positive sampling unit and the second sampling error of the negative sampling unit. This is suitable for an application environment in which the positive-to-ground voltage and the negative-to-ground voltage are sampled respectively by two sampling units, thereby improving the accuracy of the insulation performance test results in this application environment.

[0023] In one embodiment, determining the reference ratio according to the first sampling error of the positive sampling unit and the second sampling error of the negative sampling unit in the sampling error information includes:

[0024] Obtaining a difference function between a first error function and a second error function; the first error function includes a first sampling error, and the second error function includes a second sampling error;

[0025] Obtaining voltage data collected by the positive sampling unit and the negative sampling unit under working conditions with different insulation resistance values;

[0026] The reference ratio is determined based on the voltage data and the difference function under various working conditions.

[0027] In the embodiment of the present application, the process of determining the reference ratio is converted into a function problem, which is suitable for program implementation and improves the efficiency of determining the reference ratio.

[0028] In one embodiment, determining the reference ratio according to the voltage data and the difference function under various working conditions includes:

[0029] For each working condition, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the negative electrode reference-to-ground voltage, and the positive electrode reference-to-ground voltage in the voltage data are input into the difference function to obtain the difference value under the working condition;

[0030] The reference ratio is determined based on the difference values ​​under each working condition.

[0031] In an embodiment of the present application, a difference value is determined based on voltage data under actual working conditions, so as to determine a reference ratio according to the specific difference value, thereby improving the matching degree between the obtained reference ratio and the actual working conditions, and can correspondingly improve the accuracy of the insulation performance test results obtained based on the reference ratio.

[0032] In one embodiment, determining the reference ratio according to the difference values ​​under various working conditions includes:

[0033] The working condition corresponding to the difference value with the smallest absolute value among all working conditions is determined as the target working condition;

[0034] The positive electrode-to-ground voltage and the negative electrode-to-ground voltage under the target operating condition are obtained, and a reference ratio is determined according to the ratio of the positive electrode-to-ground voltage to the negative electrode-to-ground voltage under the target operating condition.

[0035] In an embodiment of the present application, the target operating condition corresponds to the operating condition with the smallest absolute value of the difference value. The reference ratio is determined based on the positive pole-to-ground voltage and the negative pole-to-ground voltage under the target operating condition, which can correspondingly improve the accuracy of the insulation performance test results obtained based on the reference ratio.

[0036] In one embodiment, determining a target measurement circuit according to an electrode-to-ground voltage and a reference ratio includes:

[0037] Obtain the positive-to-negative voltage ratio of the positive electrode voltage to ground and the negative electrode voltage to ground;

[0038] When the positive-to-negative voltage ratio is greater than the reference ratio, determining that the target measurement circuit is a positive electrode measurement circuit of the battery to be tested;

[0039] When the positive-to-negative voltage ratio is less than or equal to the reference ratio, the target measurement circuit is determined to be the negative electrode measurement circuit of the battery to be measured.

[0040] In the embodiment of the present application, the reference ratio is a critical parameter determined based on different actual operating conditions and sampling error information of the voltage sampling unit, taking into account the impact of the sampling error on different actual operating conditions of the battery, thereby improving the accuracy and reliability of the detection results.

[0041] In one embodiment, the current balance relationship expression includes an expression of a first state and an expression of a second state; according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, and the reference-to-ground voltage, obtaining the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested, including:

[0042] Input the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit of the battery to be tested, and the resistance value of the resistor unit in the negative electrode measurement circuit into the expression of the first state, input the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit, the resistance value of the resistor unit in the negative electrode measurement circuit, and the reference voltage to ground into the expression of the second state, and solve to obtain the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested;

[0043] The first state indicates that both the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are in the on state; the second state indicates that one of the positive electrode measurement circuit and the negative electrode measurement circuit is in the off state and the other is in the on state.

[0044] In the embodiment of the present application, the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested are determined based on the expression of the first state and the expression of the second state formed by the positive electrode measurement circuit and the negative electrode measurement circuit in different on-off states, and the positive electrode insulation resistance and the negative electrode insulation resistance are solved by connecting the two state expressions, thereby improving the detection efficiency.

[0045] In a second aspect, an embodiment of the present application further provides an insulation performance detection device, the device comprising:

[0046] A first acquisition module is used to acquire the electrode-to-ground voltage of the battery to be tested collected by the voltage sampling unit; the electrode-to-ground voltage includes a positive electrode-to-ground voltage and a negative electrode-to-ground voltage;

[0047] A second acquisition module, configured to acquire a reference ground voltage of the battery to be tested collected by the voltage sampling unit according to sampling error information of the voltage sampling unit;

[0048] A resistance acquisition module is used to obtain the insulation resistance of the positive electrode and the insulation resistance of the negative electrode of the battery to be tested according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode voltage to ground, the negative electrode voltage to ground and the reference voltage to ground;

[0049] The result determination module is used to determine the insulation performance test result of the battery to be tested according to the positive electrode insulation resistance value and the negative electrode insulation resistance value.

[0050] In a third aspect, an embodiment of the present application further provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps in the insulation performance detection method provided in any one of the embodiments of the first aspect are implemented.

[0051] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the insulation performance detection provided in any one of the embodiments of the first aspect above.

[0052] In a fifth aspect, an embodiment of the present application further provides a computer program product, including a computer program, which, when executed by a processor, implements the steps in the insulation performance detection provided in any one of the embodiments of the first aspect above.

[0053] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A schematic diagram of an application environment of an insulation performance detection method in an embodiment;

[0055] Figure 2 A schematic diagram of a flow chart of an insulation performance detection method in one embodiment;

[0056] Figure 3 A schematic diagram of a process for obtaining a reference voltage to ground in one embodiment;

[0057] Figure 4 A schematic diagram of a flow chart for determining a target measurement circuit in one embodiment;

[0058] Figure 5 A schematic diagram of a process for determining a reference ratio in one embodiment;

[0059] Figure 6 A schematic diagram of a flow chart for determining a reference ratio in another embodiment;

[0060] Figure 7 A schematic diagram of a flow chart for determining a reference ratio in another embodiment;

[0061] Figure 8 A schematic diagram of a flow chart for determining a target measurement circuit in another embodiment;

[0062] Fig. 9 A schematic diagram of a flow chart of an insulation performance detection method in another embodiment;

[0063] Fig.10 A schematic diagram of a reference ratio flow chart in another embodiment;

[0064] Fig.11 is a structural block diagram of an insulation performance detection device in one embodiment;

[0065] Fig.12 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the term "including" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0068] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0069] In the description of the embodiments of the present application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. In the description of the embodiments of the present application, the term "plurality" refers to more than two (including two), unless otherwise clearly and specifically defined.

[0070] With the continuous development of new energy technologies, more and more devices use electricity as a power source.

[0071] Take new energy vehicles as an example. New energy vehicles use batteries as their power source, which have the characteristics of high voltage and high current. For high-voltage and high-current power batteries, it is very important to maintain good insulation performance.

[0072] In the related art, an insulation detection circuit is usually configured for the battery to be tested to detect the insulation performance of the battery and determine whether the insulation performance of the battery meets the requirements. The insulation detection circuit includes a voltage sampling unit for voltage sampling. The control chip can calculate the insulation resistance value of the battery to be tested based on the voltage data collected by the voltage sampling unit as the insulation performance test result of the battery to be tested.

[0073] However, due to the influence of electrical components (such as analog-to-digital converters) in the voltage sampling unit, the voltage sampling unit has inherent sampling errors, which directly affects the accuracy of the collected voltage data, and correspondingly reduces the accuracy of the insulation performance test results obtained based on the voltage data. In addition, for the case where two voltage sampling units are included to respectively sample the positive electrode-to-ground voltage and the negative electrode-to-ground voltage of the battery to be tested, the sampling error deviation between the two voltage sampling units aggravates the problem of voltage data accuracy, increases the gap between the test results and the actual situation, and reduces the accuracy of the test results.

[0074] To this end, the present application provides a method for detecting insulation performance, which can be applied to Figure 1 In the application environment shown. The positive electrode of the battery 100 to be tested is connected to the resistor unit M1 and grounded through the switch S1 to form a positive electrode measurement circuit, and the negative electrode is connected to the resistor unit M2 and grounded through the switch S2 to form a negative electrode measurement circuit. The positive electrode measurement circuit and the negative electrode measurement circuit are connected to the voltage sampling unit A to collect the positive electrode-to-ground voltage of the battery to be tested when the switch S1 is closed, and the negative electrode-to-ground voltage of the battery to be tested when the switch S2 is closed. The control chip 200 can obtain the voltage data collected by the voltage sampling unit A to determine the insulation performance test result of the battery 100 to be tested based on the voltage data.

[0075] Those skilled in the art will understand that Figure 1 The structure shown in the figure is only a block diagram of a partial structure related to the embodiment of the present application, and does not constitute a limitation on the computer device to which the embodiment of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0076] In one embodiment, the present application provides a method for detecting insulation performance. Figure 1 Take the control chip in as an example. Figure 2 As shown, the method comprises the following steps:

[0077] S210, acquiring the electrode-to-ground voltage of the battery to be tested collected by a voltage sampling unit; the electrode-to-ground voltage includes a positive electrode-to-ground voltage and a negative electrode-to-ground voltage.

[0078] The voltage acquisition unit includes a positive sampling unit and a negative sampling unit. The positive sampling unit samples the positive electrode-to-ground voltage of the battery to be tested, and the negative sampling unit samples the negative electrode-to-ground voltage of the battery to be tested.

[0079] Optionally, the control chip can respectively obtain the positive electrode-to-ground voltage and the negative electrode-to-ground voltage collected by the positive electrode sampling unit and the negative electrode-to-ground voltage collected by the negative electrode sampling unit, and use the positive electrode-to-ground voltage and the negative electrode-to-ground voltage of the battery to be tested as the electrode-to-ground voltage of the battery to be tested.

[0080] S220 . Obtain, according to sampling error information of the voltage sampling unit, a reference ground voltage of the battery to be tested collected by the voltage sampling unit.

[0081] In practical applications, the voltage sampling unit includes an analog-to-digital converter (ADC), and the sampling error information of the voltage sampling unit can be calculated based on the sampling digital quantity bit number of the ADC and the error unit value, and can be directly read and used in practical applications. Exemplarily, the error unit value includes but is not limited to unadjustable error, integral nonlinear error, gain error, differential nonlinear error, offset error, root mean square noise error, etc.

[0082] Optionally, the control chip can read the sampling error information of the pre-configured positive sampling unit and the negative sampling unit respectively, or can calculate the sampling error information of the positive sampling unit and the sampling error information of the negative sampling unit according to the sampling digital quantity bit number and error unit value of the ADC in the positive sampling unit and the negative sampling unit input by the user. The sampling error information is usually represented by an error percentage.

[0083] After obtaining the sampling error information of the positive sampling unit and the negative sampling unit, the control chip can control the positive electrode sampling unit or the negative electrode sampling unit to collect the positive electrode-to-ground voltage or the negative electrode-to-ground voltage of the battery to be tested again based on the sampling error information of the two sampling units as the reference voltage to ground of the battery to be tested.

[0084] For example, the larger the sampling error information, the worse the sampling accuracy. Based on this, the control chip can compare the sampling error information of the positive sampling unit with the sampling error information of the negative sampling unit, determine the sampling unit with the smaller sampling error information, and obtain the voltage to ground obtained by the sampling unit as the reference voltage to ground.

[0085] For example, when the sampling error information of the positive sampling unit is greater than the sampling error information of the negative sampling unit, the negative electrode-to-ground voltage of the battery to be tested collected by the negative sampling unit is obtained as a reference voltage to ground; when the sampling error information of the positive sampling unit is less than the sampling error information of the negative sampling unit, the positive electrode-to-ground voltage of the battery to be tested collected by the positive sampling unit is obtained as a reference voltage to ground; when the sampling error information of the positive sampling unit is equal to the sampling error information of the negative sampling unit, the positive electrode-to-ground voltage of the battery to be tested collected by the positive sampling unit is obtained as a reference voltage to ground, or the negative electrode-to-ground voltage of the battery to be tested collected by the negative sampling unit is obtained as a reference voltage to ground.

[0086] S230, obtaining the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode voltage to ground, the negative electrode voltage to ground and the reference voltage to ground.

[0087] The current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested can be obtained based on Kirchhoff's voltage law. The current balance relationship expression includes the correlation between the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the reference-to-ground voltage, and the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested.

[0088] Optionally, the control chip can directly read the current balance relationship expression between the positive and negative electrodes of the battery to be tested, which is pre-constructed based on Kirchhoff's voltage law, and input the collected positive electrode-to-ground voltage, negative electrode-to-ground voltage and reference-to-ground voltage of the battery to be tested into the current balance relationship expression to calculate the positive electrode insulation resistance and negative electrode insulation resistance of the battery to be tested.

[0089] S240: Determine the insulation performance test result of the battery to be tested according to the positive electrode insulation resistance value and the negative electrode insulation resistance value.

[0090] The insulation performance test result of the battery to be tested is used to characterize the insulation performance of the battery to be tested. Exemplarily, the insulation performance test result may include a binary classification result of whether the battery to be tested meets the insulation requirements, and may also include the insulation resistance value of the battery to be tested.

[0091] Optionally, the control chip can directly use the obtained positive electrode insulation resistance and negative electrode insulation resistance of the battery to be tested as the insulation performance test result of the battery to be tested, or it can determine whether the battery to be tested meets the insulation requirements based on the positive electrode insulation resistance and the negative electrode insulation resistance, and use whether the battery to be tested meets the insulation requirements as the insulation performance test result of the battery to be tested.

[0092] Exemplarily, when the positive electrode insulation resistance of the battery to be tested is greater than the positive electrode insulation threshold, and the negative electrode insulation resistance is greater than the negative electrode insulation threshold, the control chip determines that the insulation performance test result of the battery to be tested is that the battery to be tested meets the insulation requirements; conversely, when the positive electrode insulation resistance of the battery to be tested is less than or equal to the positive electrode insulation threshold, or the negative electrode insulation resistance is less than or equal to the negative electrode insulation threshold, the control chip determines that the insulation performance test result of the battery to be tested is that the battery to be tested does not meet the insulation requirements.

[0093] In an embodiment of the present application, the electrode-to-ground voltage of the battery to be tested collected by the voltage sampling unit is obtained, and the reference-to-ground voltage of the battery to be tested collected by the voltage sampling unit is obtained according to the sampling error information of the voltage sampling unit, so as to determine the insulation performance test result of the battery to be tested according to the electrode-to-ground voltage and the reference-to-ground voltage; the electrode-to-ground voltage includes the positive electrode-to-ground voltage and the negative electrode-to-ground voltage. In the above method, during the insulation performance detection process, the reference voltage to ground is determined based on the sampling error information of the voltage sampling unit, so as to determine the insulation performance detection result of the battery to be tested according to the positive electrode to ground voltage, the negative electrode to ground voltage and the reference voltage to ground, taking into account the influence of the sampling error information of the voltage sampling unit on the detection result, and correspondingly improving the accuracy of the insulation performance detection result, and the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested can be used to accurately reflect the correlation between the positive electrode to ground voltage, the negative electrode to ground voltage, the reference voltage to ground, the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested, and the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested are determined based on the current balance relationship expression to determine the insulation performance detection result of the battery to be tested, thereby improving the data comprehensiveness and accuracy of the detection result.

[0094] Based on this, in one embodiment, the above S210, obtaining the electrode-to-ground voltage of the battery to be tested collected by the voltage sampling unit, includes:

[0095] When the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are both in the on state, the positive electrode sampling unit in the control voltage sampling unit collects the positive electrode-to-ground voltage of the battery to be tested, and the negative electrode sampling unit in the control voltage sampling unit collects the negative electrode-to-ground voltage of the battery to be tested.

[0096] like Figure 1 As shown, the positive sampling unit A1 is used to sample the voltage across the resistor unit M1 in the positive measurement circuit as the positive electrode-to-ground voltage Up1 of the battery to be tested; the negative sampling unit A2 is used to sample the voltage across the resistor unit M2 in the negative measurement circuit as the negative electrode-to-ground voltage Un1 of the battery to be tested.

[0097] Optionally, the control chip can control switches S1 and S2 to turn on the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested, so that when both the positive electrode measurement circuit and the negative electrode measurement circuit are in the on state, the positive electrode sampling unit is controlled to collect the positive electrode-to-ground voltage of the battery to be tested, and the negative electrode sampling unit is controlled to collect the negative electrode-to-ground voltage of the battery to be tested.

[0098] In the embodiment of the present application, the electrode-to-ground voltage includes the positive electrode-to-ground voltage and the negative electrode-to-ground voltage. When the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are both in the on state, the positive electrode sampling unit in the voltage sampling unit is controlled to collect the positive electrode-to-ground voltage of the battery to be tested, and the negative electrode sampling unit in the voltage sampling unit is controlled to collect the negative electrode-to-ground voltage of the battery to be tested. In the above method, when the positive electrode measurement circuit and the negative electrode measurement circuit are both in the on state, the positive electrode-to-ground voltage of the battery to be tested is collected by the positive electrode sampling unit, and the negative electrode-to-ground voltage of the battery to be tested is collected by the negative electrode sampling unit, so as to provide for the subsequent determination of the insulation performance test result of the battery to be tested, thereby improving the comprehensiveness of the data and simultaneously improving the reliability of the insulation performance test result.

[0099] The reference voltage to ground of the battery to be tested is the voltage to ground of the measuring circuit in the conducting state, which is collected when one of the positive electrode measuring circuit and the negative electrode measuring circuit is in the conducting state and the other is in the disconnected state. Figure 3 As shown, the above S220, obtaining the reference ground voltage of the battery to be tested collected by the voltage sampling unit according to the sampling error information of the voltage sampling unit, includes:

[0100] S310, determining a target measurement circuit to be disconnected in the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested according to the sampling error information.

[0101] Optionally, after respectively obtaining the error information of the positive sampling unit and the negative sampling unit, the control chip may compare the two to determine the measurement circuit to be disconnected in the positive measurement circuit and the negative measurement circuit according to the comparison result as the target measurement circuit.

[0102] Exemplarily, the control chip may determine that the positive measurement circuit is the target measurement circuit to be disconnected when the sampling error information of the positive sampling unit is greater than the sampling error information of the negative sampling unit; conversely, when the sampling error information of the positive sampling unit is less than the sampling error information of the negative sampling unit, determine that the negative measurement circuit is the target measurement circuit to be disconnected; and, when the sampling error information of the positive sampling unit is equal to the sampling error information of the negative sampling unit, determine that either the positive measurement circuit or the negative measurement circuit is the target measurement circuit to be disconnected.

[0103] S320: When the target measurement circuit is in a disconnected state, control the voltage sampling unit to collect the reference ground voltage of the battery to be measured.

[0104] Optionally, after determining the target measurement circuit to be disconnected, the control chip may control a switch in the target measurement circuit to be disconnected, so as to control the voltage sampling unit to collect the reference voltage to ground of the battery to be tested when the target measurement circuit is in a disconnected state.

[0105] Exemplarily, after obtaining the positive electrode-to-ground voltage and the negative electrode-to-ground voltage when both the positive electrode measurement circuit and the negative electrode measurement circuit are in the on state, when it is determined that the target measurement circuit is the positive electrode measurement circuit, the control chip can control the switch S1 to be disconnected and keep the switch S2 closed, so as to control the negative electrode sampling unit to collect the negative electrode-to-ground voltage Un2 of the battery to be tested as the reference voltage to ground (i.e., the negative electrode reference voltage to ground); when it is determined that the target measurement circuit is the negative electrode measurement circuit, the control chip can control the switch S2 to be disconnected and keep the switch S1 closed, so as to control the positive electrode sampling unit to collect the positive electrode-to-ground voltage Up2 of the battery to be tested as the reference voltage to ground (i.e., the positive electrode reference voltage to ground).

[0106] In an embodiment of the present application, the target measurement circuit to be disconnected in the positive measurement circuit and the negative measurement circuit of the battery to be tested is determined based on the sampling error information, and when the target measurement circuit is in a disconnected state, the voltage sampling unit is controlled to collect the reference ground voltage of the battery to be tested. In the above method, the target measurement circuit to be disconnected is determined based on the sampling error information to obtain the ground voltage of the closed measurement circuit as the reference ground voltage for subsequent determination of the insulation performance test result of the battery to be tested, thereby achieving a more accurate reference ground voltage based on the sampling error information, and correspondingly improving the accuracy of the insulation performance test result determined based on the reference ground voltage.

[0107] In the case where the voltage sampling unit includes a positive sampling unit and a negative sampling unit, the sampling error information of the voltage sampling unit correspondingly includes a first sampling error of the positive sampling unit and a second sampling error of the negative sampling unit. Figure 4 As shown, the above S310, determining the target measurement circuit to be disconnected in the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested according to the sampling error information, includes:

[0108] S410 : Determine a reference ratio according to a first sampling error of a positive sampling unit and a second sampling error of a negative sampling unit in the sampling error information.

[0109] The first sampling error is determined based on the hardware configuration information of the positive sampling unit, and the second sampling error is determined based on the hardware configuration information of the negative sampling unit. The reference ratio voltage is used to indicate the target measurement circuit to be disconnected in the positive measurement circuit and the negative measurement circuit.

[0110] Optionally, for the case where the voltage sampling unit includes a positive sampling unit and a negative sampling unit, the control chip can read the first sampling error of the positive sampling unit and the second sampling error of the negative sampling unit in the sampling error information to determine the reference ratio according to the first sampling error and the second sampling error.

[0111] S420: Determine a target measurement circuit according to the electrode-to-ground voltage and a reference ratio.

[0112] Optionally, the control chip may obtain the ratio between the positive electrode voltage to ground and the negative electrode voltage to ground of the battery to be tested, that is, the positive-negative voltage ratio, to determine the target measurement circuit according to the positive-negative voltage ratio and the reference ratio.

[0113] In the embodiment of the present application, the voltage sampling unit includes a positive sampling unit and a negative sampling unit, and a reference ratio is determined according to the first sampling error of the positive sampling unit in the sampling error information and the second sampling error of the negative sampling unit, and a target measurement circuit is determined according to the electrode-to-ground voltage and the reference ratio. In the above method, based on the case where the voltage sampling unit includes a positive sampling unit and a negative sampling unit, the target measurement circuit is simultaneously determined by the first sampling error of the positive sampling unit and the second sampling error of the negative sampling unit, which is suitable for an application environment where the positive-to-ground voltage and the negative-to-ground voltage are sampled by two sampling units respectively, thereby improving the accuracy of the insulation performance detection results in the application environment.

[0114] In practical applications, the reference ratio can be determined by combining the voltage data of the battery under test under different insulation resistance conditions. Figure 5 As shown, the above S410, determining the reference ratio according to the first sampling error of the positive sampling unit and the second sampling error of the negative sampling unit in the sampling error information, includes:

[0115] S510, obtaining a difference function between a first error function and a second error function; the first error function includes a first sampling error, and the second error function includes a second sampling error.

[0116] The first error function is used to characterize the error information generated by the positive sampling unit, and the second error function is used to characterize the error information generated by the negative sampling unit.

[0117] It should be noted that when subsequently determining the insulation performance test result of the battery to be tested, not only the reference voltage to ground is required, but also the voltage to ground of another electrode needs to be determined based on the reference voltage to ground, thereby introducing a new voltage error.

[0118] Therefore, the first error function includes not only the first sampling error of the positive sampling unit, but also the first voltage error introduced by the positive sampling unit; correspondingly, the second error function includes not only the second sampling error of the negative sampling unit, but also the second voltage error introduced by the negative sampling unit.

[0119] Exemplarily, the first sampling error of the positive sampling unit is α, and when the reference voltage to ground is the positive reference voltage to ground Up2 collected by the positive sampling unit, the first voltage error introduced is Up2*α / (Up1+Un1-Up2), and the first error function F1 is determined based on the first sampling error and the first voltage error. For example, F1=α+Up2*α / (Up1+Un1-Up2); Up1+Un1-Up2 represents the negative voltage to ground determined based on the positive reference voltage to ground Up2. Similarly, the second sampling error of the negative sampling unit is β, and when the reference voltage to ground is the negative reference voltage to ground Un2 collected by the positive sampling unit, the second voltage error introduced is Un2*β / (Up1+Un1-Un2), and the second error function F2 is determined based on the second sampling error and the second voltage error. For example, F2=β+Un2*β / (Up1+Un1-Un2); Up1+Un1-Un2 represents the positive voltage to ground determined based on the negative reference voltage to ground Un2.

[0120] Optionally, after obtaining the first error function and the second error function, the control chip may use an expression of the first error function minus the second error function as a difference function between the first error function and the second error function, wherein the difference function F=F1-F2.

[0121] S520: Obtain voltage data collected by the positive electrode sampling unit and the negative electrode sampling unit under working conditions with different insulation resistance values.

[0122] Optionally, before acquiring voltage data, the user can Figure 1 The battery to be tested is replaced with a reference battery with a known insulation resistance value. The control chip can obtain the voltage data collected by the positive sampling unit and the negative sampling unit under the working condition, and the reference battery is updated. The control chip can correspondingly obtain the voltage data under the new working condition.

[0123] S530: Determine a reference ratio according to the voltage data and the difference function under each working condition.

[0124] Optionally, after obtaining the voltage data under each working condition, the voltage data under each working condition may be substituted into the determined difference function to obtain the difference value corresponding to each working condition, and the reference ratio may be determined based on the difference value corresponding to each working condition.

[0125] In an embodiment of the present application, by obtaining a difference function between a first error function and a second error function, and obtaining voltage data collected by a positive sampling unit and a negative sampling unit under working conditions with different insulation resistance values, a reference ratio is determined based on the voltage data and the difference function under each working condition; the first error function includes a first sampling error, and the second error function includes a second sampling error; in the above method, the process of determining the reference ratio is converted into a function problem, which is suitable for program implementation, thereby improving the efficiency of determining the reference ratio.

[0126] The voltage data under each working condition includes the voltage data collected at different sampling stages. Based on this, in one embodiment, Figure 6 As shown, the above S530, determining the reference ratio according to the voltage data and the difference function under each working condition, includes:

[0127] S610. For each working condition, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the negative electrode reference-to-ground voltage, and the positive electrode reference-to-ground voltage in the voltage data are input into a difference function to obtain a difference value under the working condition.

[0128] The different sampling stages include a first sampling stage and a second sampling stage after the first sampling stage. The first sampling stage corresponds to a stage in which both the positive electrode measurement circuit and the negative electrode measurement circuit are in an on state; the second sampling stage corresponds to a stage in which one of the positive electrode measurement circuit and the negative electrode measurement circuit is in an on state and the other is in an off state.

[0129] The positive voltage to ground and the negative voltage to ground in the voltage data correspond to those collected by the positive sampling unit and the negative sampling unit respectively in the first sampling phase. The negative reference voltage to ground and the positive reference voltage to ground correspond to those collected by the negative sampling unit / positive sampling unit in the second sampling phase.

[0130] Optionally, after obtaining the voltage data under different working conditions, for each working condition, the control chip can input the positive pole-to-ground voltage, negative pole-to-ground voltage, negative pole reference-to-ground voltage and positive pole reference-to-ground voltage in the voltage data under that working condition into a difference function to calculate the difference value under that working condition.

[0131] S620. Determine a reference ratio according to the difference values ​​under each working condition.

[0132] Optionally, after obtaining the difference values ​​under each working condition, the control chip can determine a reference ratio based on each difference value. For example, the control chip can filter difference values ​​that meet a preset value range from all difference values, and obtain the average value of the ratio of the positive electrode voltage to the negative electrode voltage to the ground obtained by obtaining these difference values ​​as the reference ratio.

[0133] In the embodiment of the present application, for each working condition, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the negative electrode reference-to-ground voltage, and the positive electrode reference-to-ground voltage in the voltage data are input into the difference function to obtain the difference value under the working condition, so as to determine the reference ratio according to the difference value under each working condition. In the above method, the difference value is determined based on the voltage data under the actual working condition, so as to determine the reference ratio according to the specific difference value, thereby improving the matching degree between the obtained reference ratio and the actual working condition, and correspondingly improving the accuracy of the insulation performance test result obtained based on the reference ratio.

[0134] The reference ratio is the ratio of the positive electrode voltage to the ground to the negative electrode voltage to the ground under the target operating condition. Figure 7 As shown, the above S620, determining the reference ratio according to the difference values ​​under each working condition, includes:

[0135] S710. Determine the operating condition corresponding to the difference value with the smallest absolute value among all operating conditions as the target operating condition.

[0136] Optionally, after obtaining the difference values ​​under each operating condition, the control chip may compare the difference values, determine the difference value with the smallest absolute value, and determine the operating condition corresponding to the difference value with the smallest absolute value as the target operating condition.

[0137] S720: Obtain the positive electrode-to-ground voltage and the negative electrode-to-ground voltage under the target operating condition, and determine a reference ratio according to the ratio of the positive electrode-to-ground voltage to the negative electrode-to-ground voltage under the target operating condition.

[0138] Optionally, after determining the target operating condition, the control chip can obtain the positive pole-to-ground voltage and the negative pole-to-ground voltage in the voltage data under the target operating condition to obtain the ratio of the positive pole-to-ground voltage to the negative pole-to-ground voltage, and determine the reference ratio based on the ratio.

[0139] Exemplarily, the control chip can directly use the ratio as a reference ratio, or it can perform mathematical processing on the ratio to obtain a reference ratio, such as converting the ratio into 1 / N using the nearest principle, where N is a positive integer, and using the converted 1 / N as a reference ratio.

[0140] In the embodiment of the present application, the operating condition corresponding to the difference value with the smallest absolute value in each operating condition is determined as the target operating condition to obtain the positive electrode-to-ground voltage and the negative electrode-to-ground voltage under the target operating condition, and the reference ratio is determined according to the ratio of the positive electrode-to-ground voltage to the negative electrode-to-ground voltage under the target operating condition. In the above method, the target operating condition corresponds to the operating condition with the smallest absolute value of the difference value, and the reference ratio is determined based on the positive electrode-to-ground voltage and the negative electrode-to-ground voltage under the target operating condition, which can correspondingly improve the accuracy of the insulation performance test result obtained based on the reference ratio.

[0141] The electrode-to-ground voltage includes a positive electrode-to-ground voltage and a negative electrode-to-ground voltage. In one embodiment, Figure 8 As shown, the above S420, determining the target measurement circuit according to the electrode-to-ground voltage and the reference ratio, includes:

[0142] S810: Obtain a positive-to-negative voltage ratio of a positive electrode voltage to ground and a negative electrode voltage to ground.

[0143] Optionally, after the control chip obtains the positive-to-ground voltage and the negative-to-ground voltage in the first sampling phase, it can calculate the ratio of the positive-to-ground voltage to the negative-to-ground voltage, that is, the positive-to-negative voltage ratio. Among them, the positive-to-ground voltage is Up1, the negative-to-ground voltage is Un1, and the positive-to-negative voltage ratio is Up1 / Un1.

[0144] S820: When the positive-to-negative voltage ratio is greater than the reference ratio, determine that the target measurement circuit is a positive electrode measurement circuit.

[0145] Optionally, after obtaining the positive-negative voltage ratio, the control chip can compare the positive-negative voltage ratio with a reference ratio, and when the positive-negative voltage ratio is greater than the reference ratio, determine that the target measurement circuit is a positive measurement circuit, that is, determine that the positive measurement circuit needs to be disconnected.

[0146] S830: When the positive-to-negative voltage ratio is less than or equal to the reference ratio, determine that the target measurement circuit is a negative electrode measurement circuit.

[0147] Optionally, after obtaining the positive-negative voltage ratio, the control chip can compare the positive-negative voltage ratio with a reference ratio, and when the positive-negative voltage ratio is less than or equal to the reference ratio, determine that the target measurement circuit is a negative pole measurement circuit, that is, determine that the negative pole measurement circuit needs to be disconnected.

[0148] In the embodiment of the present application, the positive-to-negative voltage ratio of the positive-to-ground voltage and the negative-to-ground voltage is obtained, and when the positive-to-negative voltage ratio is greater than the reference ratio, the target measurement circuit is determined to be the positive measurement circuit; when the positive-to-negative voltage ratio is less than or equal to the reference ratio, the target measurement circuit is determined to be the negative measurement circuit. In the above method, the reference ratio is a critical parameter determined based on different actual working conditions and the sampling error information of the voltage sampling unit, taking into account the influence of the sampling error on different actual working conditions of the battery, thereby improving the accuracy and reliability of the detection result.

[0149] The current balance relationship expression includes an expression of the first state and an expression of the second state. In one embodiment, the above S240, according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage and the reference-to-ground voltage, obtains the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested, including:

[0150] Input the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit, and the resistance value of the resistor unit in the negative electrode measurement circuit into the expression of the first state, input the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit of the battery to be tested, the resistance value of the resistor unit in the negative electrode measurement circuit, and the reference voltage to ground into the expression of the second state, and solve to obtain the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested;

[0151] The first state indicates that both the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are in the on state; the second state indicates that one of the positive electrode measurement circuit and the negative electrode measurement circuit is in the off state and the other is in the on state.

[0152] It should be noted that the expression of the first state is the current balance relationship expression between the positive and negative electrodes of the battery under test in the first sampling stage, and the expression of the second state is the current balance relationship expression between the positive and negative electrodes of the battery under test in the second sampling stage.

[0153] based on Figure 1 In the application environment, the expression of the first state of the battery to be tested is as follows:

[0154] Up1 / Rp+Up1 / RS1=Un1 / Rn+Un1 / RS2 Formula 1

[0155] When the reference voltage to ground is the negative reference voltage to ground (corresponding to the second sampling stage in which the positive electrode measurement circuit is in the disconnected state and the negative electrode measurement circuit is in the on state), the expression of the second state of the battery to be tested is as follows:

[0156] (Up1+Un1-Un2) / Rp=Un2 / Rn+Un2 / RS2 Formula 2

[0157] When the reference voltage to ground is the positive reference voltage to ground (corresponding to the second sampling stage in which the positive electrode measurement circuit is in the on state and the negative electrode measurement circuit is in the off state), the expression of the second state of the battery to be tested is as follows:

[0158] (Up1+Un1-Up2) / Rp=Up2 / Rn+Up2 / RS1 Formula 3

[0159] Wherein, RS1 represents the resistance value of the resistance unit in the positive electrode measurement circuit, RS2 represents the resistance value of the resistance unit in the negative electrode measurement circuit, Rp represents the insulation resistance value of the positive electrode of the battery to be tested, and Rn represents the insulation resistance value of the negative electrode of the battery to be tested.

[0160] Optionally, when the reference voltage to ground is the negative reference voltage to ground Un2, the control chip can input the positive voltage to ground Up1 and the negative voltage to ground Un1 obtained in the first sampling stage, as well as the resistance value RS1 of the resistor unit in the positive measurement circuit and the resistance value RS2 of the resistor unit in the negative measurement circuit into Formula 1, and input the positive voltage to ground Up1, the negative voltage to ground Un1 and the negative reference voltage to ground Un2 obtained in the second sampling stage into Formula 2, and then solve Formula 1 and Formula 2 in conjunction to obtain the positive insulation resistance Rp and the negative insulation resistance Rn of the battery to be tested.

[0161] Correspondingly, when the reference voltage to ground is the positive reference voltage to ground Up2, the control chip can input the positive voltage to ground Up1 and the negative voltage to ground Un1 obtained in the first sampling stage, as well as the resistance value RS1 of the resistor unit in the positive measurement circuit and the resistance value RS2 of the resistor unit in the negative measurement circuit into Formula 1, and input the positive voltage to ground Up1, the negative voltage to ground Un1 and the positive reference voltage to ground Up2 obtained in the second sampling stage into Formula 3, and then solve Formula 1 and Formula 3 in conjunction to obtain the positive insulation resistance Rp and the negative insulation resistance Rn of the battery to be tested.

[0162] In the embodiment of the present application, the current balance relationship expression includes an expression of a first state and an expression of a second state, by inputting the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit of the battery to be tested, and the resistance value of the resistor unit in the negative electrode measurement circuit into the expression of the first state, and inputting the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit, the resistance value of the resistor unit in the negative electrode measurement circuit, and the reference voltage to ground into the expression of the second state, and solving to obtain the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested; the first state indicates that the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are both in the on state; the second state indicates that one of the positive electrode measurement circuit and the negative electrode measurement circuit is in the off state and the other is in the on state. In the above method, the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested are determined based on the expression of the first state and the expression of the second state formed by the positive electrode measurement circuit and the negative electrode measurement circuit in different on-off states, and the positive electrode insulation resistance and the negative electrode insulation resistance are solved by connecting the two state expressions, thereby improving the detection efficiency.

[0163] In order to facilitate the understanding of those skilled in the art, the insulation performance detection method provided by the present application is described in detail below. Fig. 9 As shown, the method may include:

[0164] S901, when both the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are in a conducting state, obtaining the positive electrode-to-ground voltage of the battery to be tested collected by the positive electrode sampling unit in the voltage sampling unit, and obtaining the negative electrode-to-ground voltage of the battery to be tested collected by the negative electrode sampling unit in the voltage sampling unit;

[0165] S902, obtaining a positive-to-negative voltage ratio of a positive electrode voltage to ground and a negative electrode voltage to ground;

[0166] S903, when the positive-to-negative voltage ratio is greater than the reference ratio, determining that the target measurement circuit to be disconnected between the positive measurement circuit and the negative measurement circuit is the positive measurement circuit; the reference ratio is determined based on sampling error information of the voltage sampling unit;

[0167] S904: when the positive-to-negative voltage ratio is less than or equal to the reference ratio, determine that the target measurement circuit to be disconnected between the positive measurement circuit and the negative measurement circuit is the negative measurement circuit;

[0168] S905, when the target measurement circuit is in a disconnected state, obtaining a reference ground voltage of the battery to be tested collected by a voltage sampling unit;

[0169] S906, inputting the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistance unit in the positive electrode measurement circuit, and the resistance value of the resistance unit in the negative electrode measurement circuit into the current balance relationship expression of the first state; the first state indicates that the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are both in the on state;

[0170] S907, inputting the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit, the resistance value of the resistor unit in the negative electrode measurement circuit, and the reference voltage to ground into the current balance relationship expression of the second state; the second state indicates that one of the positive electrode measurement circuit and the negative electrode measurement circuit is in an off state and the other is in an on state;

[0171] S908, the current balance relationship expression of the first state and the current balance relationship expression of the second state after the input parameters are linked, and the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested are solved.

[0172] In an optional embodiment, if Fig.10 As shown, the process of determining the reference ratio based on the sampling error information of the voltage sampling unit includes:

[0173] S1001, determining a first error function according to a first sampling error of a positive sampling unit in sampling error information; the first error function includes a first sampling error;

[0174] S1002, determining a second error function according to a second sampling error of a negative sampling unit in the sampling error information; the second error function includes a second sampling error;

[0175] S1003, obtaining a difference function between the first error function and the second error function;

[0176] S1004, obtaining voltage data collected by the positive electrode sampling unit and the negative electrode sampling unit under working conditions with different insulation resistance values;

[0177] S1005. For each working condition, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the negative electrode reference-to-ground voltage, and the positive electrode reference-to-ground voltage in the voltage data are input into a difference function to obtain a difference value under the working condition;

[0178] S1006, determining the operating condition corresponding to the difference value with the smallest absolute value among the operating conditions as the target operating condition;

[0179] S1007. Obtain the positive electrode-to-ground voltage and the negative electrode-to-ground voltage under the target operating condition, and determine a reference ratio according to the ratio of the positive electrode-to-ground voltage to the negative electrode-to-ground voltage under the target operating condition.

[0180] It should be noted that, for the descriptions in the above S901-S908 and S1001-S1007, reference can be made to the relevant descriptions in the above embodiments, and the effects are similar, which will not be repeated in this embodiment.

[0181] The sampling error deviation between the two voltage sampling units (i.e., the positive sampling unit and the negative sampling unit) affects the target measurement circuit that needs to be disconnected in the second sampling stage (corresponding to the second state). During the insulation detection process, the voltage to ground of the closed measurement circuit obtained by sampling in the second sampling stage needs to be used to calculate the voltage to ground of the other pole, and the existence of the sampling error causes the calculation process to produce calculation error amplification. Accordingly, the existence of the sampling error deviation causes the degree of calculation error amplification to be different in different target measurement circuits. In the above insulation detection method, a reference ratio is determined based on the sampling error information of each of the two sampling units, and the target measurement circuit is selected by using the reference ratio, so that the insulation resistance of the positive electrode and the insulation resistance of the negative electrode of the battery to be tested can be calculated based on a smaller degree of calculation error amplification, thereby improving the accuracy of the detection results.

[0182] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0183] In one embodiment, Fig.11 As shown, an insulation performance detection device is provided, including: a first acquisition module 1101, a second acquisition module 1102, a resistance acquisition module 1103 and a result determination module 1104; wherein:

[0184] The first acquisition module 1101 is used to acquire the electrode-to-ground voltage of the battery to be tested collected by the voltage sampling unit; the electrode-to-ground voltage includes the positive electrode-to-ground voltage and the negative electrode-to-ground voltage;

[0185] The second acquisition module 1102 is used to acquire the reference ground voltage of the battery to be tested collected by the voltage sampling unit according to the sampling error information of the voltage sampling unit;

[0186] The resistance value acquisition module 1103 is used to acquire the insulation resistance value of the positive electrode and the insulation resistance value of the negative electrode of the battery to be tested according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage and the reference-to-ground voltage;

[0187] The result determination module 1104 is used to determine the insulation performance test result of the battery to be tested according to the positive electrode insulation resistance value and the negative electrode insulation resistance value.

[0188] Each module in the above insulation performance detection device can be implemented in whole or in part by software, hardware or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each module.

[0189] In an exemplary embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in FIG. Fig.12 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, near field communication (NFC) or other technologies. When the computer program is executed by the processor, an insulation performance detection method is implemented.

[0190] Those skilled in the art will understand that Fig.12 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0191] In one embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps of any one of the above insulation performance detection methods when executing the computer program.

[0192] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above insulation performance detection methods are implemented.

[0193] In one embodiment, a computer program product is provided, comprising a computer program, wherein when the computer program is executed by a processor, the steps of any one of the above insulation performance detection methods are implemented.

[0194] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0195] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0196] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for detecting insulation performance, characterized in that: The method comprises: When both the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are in the on state, the positive electrode sampling unit in the voltage sampling unit is controlled to collect the positive electrode-to-ground voltage of the battery to be tested, and the negative electrode sampling unit in the voltage sampling unit is controlled to collect the negative electrode-to-ground voltage of the battery to be tested, and the positive electrode-to-ground voltage and the negative electrode-to-ground voltage are used as the electrode-to-ground voltage; Determining a target measurement circuit to be disconnected in the positive measurement circuit and the negative measurement circuit according to a first sampling error of the positive sampling unit and a second sampling error of the negative sampling unit; When the target measurement circuit is in an open state, controlling the voltage sampling unit to collect the voltage to ground of the closed measurement circuit as a reference voltage to ground of the battery to be measured; Obtaining the insulation resistance value of the positive electrode and the negative electrode of the battery to be tested according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, and the reference-to-ground voltage; The insulation performance test result of the battery to be tested is determined according to the positive electrode insulation resistance value and the negative electrode insulation resistance value.

2. The method according to claim 1, characterized in that The step of determining a target measurement circuit to be disconnected in the positive measurement circuit and the negative measurement circuit according to the first sampling error of the positive sampling unit and the second sampling error of the negative sampling unit includes: Obtaining a difference function between a first error function and a second error function; the first error function includes the first sampling error, and the second error function includes the second sampling error; Acquire voltage data collected by the positive electrode sampling unit and the negative electrode sampling unit under working conditions with different insulation resistance values; For each working condition, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the negative electrode reference-to-ground voltage, and the positive electrode reference-to-ground voltage in the voltage data are input into the difference function to obtain the difference value under the working condition; The reference ratio is determined according to the difference value under each of the working conditions, and the target measurement circuit is determined according to the electrode-to-ground voltage and the reference ratio.

3. The method according to claim 2, characterized in that Determining the reference ratio according to the difference values ​​under each of the working conditions includes: Determine the operating condition corresponding to the difference value with the smallest absolute value among the operating conditions as the target operating condition; The positive electrode-to-ground voltage and the negative electrode-to-ground voltage under the target operating condition are obtained, and the reference ratio is determined according to the ratio of the positive electrode-to-ground voltage to the negative electrode-to-ground voltage under the target operating condition.

4. The method according to claim 2, characterized in that: The step of determining the target measurement circuit according to the electrode-to-ground voltage and the reference ratio includes: Obtaining a positive-to-negative voltage ratio of the positive electrode voltage to ground and the negative electrode voltage to ground; When the positive-to-negative voltage ratio is greater than the reference ratio, determining that the target measurement circuit is a positive electrode measurement circuit of the battery to be tested; When the positive-to-negative voltage ratio is less than or equal to the reference ratio, the target measurement circuit is determined to be a negative electrode measurement circuit of the battery to be measured.

5. The method according to claim 1, characterized in that The current balance relationship expression includes an expression of a first state and an expression of a second state; the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested are obtained according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode voltage to ground, the negative electrode voltage to ground and the reference voltage to ground, including: Input the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit of the battery to be tested, and the resistance value of the resistor unit in the negative electrode measurement circuit into the expression of the first state, input the positive electrode-to-ground voltage, the negative electrode-to-ground voltage, the resistance value of the resistor unit in the positive electrode measurement circuit, the resistance value of the resistor unit in the negative electrode measurement circuit, and the reference voltage to ground into the expression of the second state, and solve to obtain the positive electrode insulation resistance and the negative electrode insulation resistance of the battery to be tested; The first state indicates that both the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are in an on state; the second state indicates that one of the positive electrode measurement circuit and the negative electrode measurement circuit is in an off state and the other is in an on state.

6. The method according to claim 1, characterized in that When the target measurement circuit is a positive measurement circuit, the reference voltage to ground is the negative voltage to ground collected by the negative sampling unit; when the target measurement circuit is a negative measurement circuit, the reference voltage to ground is the positive voltage to ground collected by the positive sampling unit.

7. An insulation performance detection device, characterized in that: The device comprises: A first acquisition module is used to control the positive electrode sampling unit in the voltage sampling unit to collect the positive electrode-to-ground voltage of the battery to be tested, and to control the negative electrode sampling unit in the voltage sampling unit to collect the negative electrode-to-ground voltage of the battery to be tested, and use the positive electrode-to-ground voltage and the negative electrode-to-ground voltage as the electrode-to-ground voltage when both the positive electrode measurement circuit and the negative electrode measurement circuit of the battery to be tested are in a conducting state; A second acquisition module is used to determine a target measurement circuit to be disconnected in the positive measurement circuit and the negative measurement circuit according to a first sampling error of the positive sampling unit and a second sampling error of the negative sampling unit; when the target measurement circuit is in a disconnected state, control the voltage sampling unit to collect the ground voltage of the closed measurement circuit as a reference ground voltage of the battery to be tested; A resistance acquisition module, used to acquire the insulation resistance of the positive electrode and the insulation resistance of the negative electrode of the battery to be tested according to the current balance relationship expression between the positive electrode and the negative electrode of the battery to be tested, the positive electrode-to-ground voltage, the negative electrode-to-ground voltage and the reference-to-ground voltage; The result determination module is used to determine the insulation performance test result of the battery to be tested according to the positive electrode insulation resistance value and the negative electrode insulation resistance value.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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