Insulation resistance detection method and device, storage medium and program product

Abstract

The invention discloses an insulation resistance detection method and device, a storage medium and a program product, and belongs to the technical field of detection. The method comprises the following steps: in the charging or discharging process of a power supply device, sampling a voltage value of an equivalent capacitor of the power supply device to the ground at equal time intervals to obtain N sampling points; wherein each sampling point corresponds to one sampling time and one voltage value, and N is an integer greater than or equal to 3; selecting M groups of sampling points from the N sampling points; wherein each group of sampling points comprises three sampling points with equal sampling time intervals in the N sampling points, and M is a positive integer; determining a target steady-state voltage value of the equivalent capacitor according to the voltage values corresponding to the sampling points included in the M groups of sampling points; and determining the insulation resistance of the power supply device to the ground according to the target steady-state voltage value. According to the invention, the real-time performance and adaptability of insulation resistance detection can be improved.

Description

Technical Field

[0001] The present application belongs to the field of detection technology, and in particular, relates to an insulation resistance detection method, device, storage medium and program product. Background Art

[0002] Insulation resistance testing can be used to detect the insulation performance of a power supply device to ensure safe and stable operation of the power supply device.

[0003] The existing insulation resistance detection scheme generally adopts the national standard unbalanced bridge method. This scheme needs to sample after a delay waiting time td=k×R×Cy (where k=3, 4, 5) based on the maximum Y capacitance value Cy of the power supply device and the equivalent maximum resistance R of the bridge arm to obtain the steady-state voltage of the power supply device, and then determine the insulation resistance of the power supply resistor based on the steady-state voltage of the power supply device. This scheme needs to delay waiting to obtain the steady-state voltage of the power supply device, and the delay waiting time depends on the Y capacitance value and the equivalent resistance R. Therefore, the use of this scheme for insulation resistance detection has poor real-time performance, and different power supply devices need to configure delay waiting time separately, resulting in poor compatibility of insulation resistance detection between different power supply devices. Summary of the invention

[0004] The embodiments of the present application provide an insulation resistance detection method, device, storage medium and program product, which can solve the problems of poor real-time performance and poor adaptability of existing insulation detection solutions.

[0005] In a first aspect, an embodiment of the present application provides an insulation resistance detection method, the method comprising:

[0006] During the charging or discharging process of the power supply device, the voltage value of the equivalent capacitance of the power supply device to the ground is sampled at equal time intervals to obtain N sampling points; wherein each sampling point corresponds to a sampling time and a voltage value, and N is an integer greater than or equal to 3;

[0007] Selecting M groups of sampling points from the N sampling points; wherein each group of sampling points includes 3 sampling points with equal sampling time intervals among the N sampling points, and M is a positive integer;

[0008] Determining a target steady-state voltage value of the equivalent capacitor according to voltage values ​​corresponding to the sampling points included in the M groups of sampling points;

[0009] The insulation resistance of the power supply device to ground is determined according to the target steady-state voltage value.

[0010] In a second aspect, an embodiment of the present application provides an insulation resistance detection device, the device comprising:

[0011] A sampling module, used to sample the voltage value of the equivalent capacitance of the power supply device to the ground at equal time intervals during the charging or discharging process of the power supply device, to obtain N sampling points; wherein each of the sampling points corresponds to a sampling time and a voltage value, and N is an integer greater than or equal to 3;

[0012] A first determination module is used to select M groups of sampling points from the N sampling points; wherein each group of sampling points includes 3 sampling points with equal sampling time intervals among the N sampling points, and M is a positive integer;

[0013] A second determination module, configured to determine a target steady-state voltage value of the equivalent capacitor according to voltage values ​​corresponding to the sampling points included in the M groups of sampling points;

[0014] The third determination module is used to determine the insulation resistance of the power supply device to the ground according to the target steady-state voltage value.

[0015] In a third aspect, an embodiment of the present application provides an insulation resistance detection device, the device comprising: a processor and a memory storing computer program instructions; when the processor executes the computer program instructions, the insulation resistance detection method as described in the first aspect is implemented.

[0016] In a fourth aspect, an embodiment of the present application provides a computer storage medium, wherein the computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the insulation resistance detection method as described in the first aspect is implemented.

[0017] In a fifth aspect, an embodiment of the present application provides a computer program product. When instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the insulation resistance detection method as described in the first aspect.

[0018] In an embodiment of the present application, during the charging or discharging process of the power supply device, the voltage value of the equivalent capacitance of the power supply device to the ground can be sampled at equal time intervals to obtain N sampling points, each sampling point corresponds to a sampling time and a voltage value, and N is an integer greater than 1 or equal to 3. Then, 3 sampling points with equal sampling time intervals are selected from the N sampling points to form a group of sampling points to obtain M groups of sampling points. Afterwards, the target steady-state voltage value of the equivalent capacitance can be determined using the voltage value corresponding to the sampling point of at least one group of sampling points in the M groups of sampling points, and then the insulation resistance of the power supply device to the ground can be obtained. It can be seen that the steady-state voltage can be determined by the voltage value corresponding to the sampling point obtained by sampling at equal time intervals in the embodiment of the present application. In this way, the real-time acquisition of the steady-state voltage can be improved, and the influence of the Y capacitance value and the equivalent resistance R on the determination of the steady-state voltage can be eliminated, thereby improving the real-time and adaptability of the insulation resistance detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0020] Figure 1 It is a flow chart of the insulation resistance detection method provided in the embodiment of the present application;

[0021] Figure 2 is a schematic diagram of a capacitor charge and discharge curve provided in an embodiment of the present application;

[0022] Figure 3 is a structural schematic diagram of an insulation resistance detection device provided in an embodiment of the present application;

[0023] Figure 4 It is a structural schematic diagram of the insulation resistance detection device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0025] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0026] For ease of understanding, some contents involved in the embodiments of the present application are described below:

[0027] The embodiments of the present application do not limit the power supply device and specific form.

[0028] In some embodiments, the power supply device may be a battery. In these embodiments, insulation resistance detection may be used to detect whether there is insulation failure inside the battery to the housing (i.e., ground). When the insulation detection function is enabled, if the battery detects insulation failure during operation, the system will issue a battery insulation failure alarm and interrupt the output of the battery, thereby ensuring that the battery stops operating to avoid potential safety risks. This detection mechanism is critical to ensuring the safety and stability of the battery.

[0029] In other embodiments, the power supply resistor may be a high-voltage electrical device in the power system. In these embodiments, the insulation resistance test may be used to test the insulation performance of the high-voltage electrical device in the power system to ensure the safe and stable operation of the power system. This test measures the insulation resistance value of the device to assess whether the device can withstand the influence of adverse factors such as the external environment, high voltage, corrosion, and machinery during operation, thereby preventing equipment failure or power interruption.

[0030] The existing insulation detection scheme generally adopts the national standard unbalanced bridge method, which provides the maximum Y capacitance value Cy according to the vehicle or energy storage system, combined with the equivalent maximum resistance R of the bridge arm; sampling is performed after the delay waiting time td = k*R*Cy, (where k = 3, 4, 5), and the steady-state voltage V of this step is obtained. end This detection method takes a long time to detect and has poor real-time performance. When different vehicle models or energy storage system maximum Y capacitance values ​​Cy are different, an additional delay waiting time td needs to be configured.

[0031] Therefore, the embodiments of the present application aim to provide an insulation resistance detection method, device, storage medium and program product to solve the problems of long time to obtain steady-state voltage, poor real-time performance and poor adaptability during insulation resistance detection.

[0032] The insulation resistance detection method provided in the embodiment of the present application is described in detail below through some embodiments and their application scenarios in combination with the accompanying drawings.

[0033] See also Figure 1 , Figure 1 : is a flow chart of the insulation resistance detection method provided in the embodiment of the present application. Figure 1 As shown, the insulation resistance detection method may include the following steps:

[0034] Step 101: During the charging or discharging process of the power supply device, the voltage value of the equivalent capacitance of the power supply device to the ground is sampled at equal time intervals to obtain N sampling points; wherein each sampling point corresponds to a sampling time and a voltage value, and N is an integer greater than or equal to 3.

[0035] Sampling the voltage value of the equivalent capacitor at equal time intervals can be understood as: performing a sampling task of the voltage value of the equivalent capacitor at equal time intervals (hereinafter referred to as Δt1 ).

[0036] Δt1 can be set based on actual needs and can be a time in seconds, such as 10s or 15s.

[0037] Each time a sampling task is executed, a sampling point can be obtained. The sampling time corresponding to each sampling point is the execution time of the sampling task corresponding to the sampling point, and the voltage value corresponding to each sampling point can be determined based on the voltage value of the equivalent capacitor sampled by the sampling task corresponding to the sampling point.

[0038] In the embodiment of the present application, the sampling of the voltage value of the equivalent capacitor at equal time intervals can occur during the charging process or the discharging process of the power supply device. It can be understood that the N sampling points are all sampling points obtained by sampling at equal time intervals during the charging process of the power supply device, or the N sampling points are all sampling points obtained by sampling at equal time intervals during the discharging process of the power supply device. It can be seen that the embodiment of the present application can determine the steady-state voltage of the equivalent capacitor by sampling the voltage value of the equivalent capacitor at equal time intervals during the charging or discharging process of the power supply device, and then determine the insulation resistance of the power supply device to the ground, so that the detection scenario of the insulation resistance can be enriched.

[0039] In the embodiment of the present application, N can be any integer greater than or equal to 3, such as N can be 3, 4, or the like. The specific setting can be based on actual needs and is not limited here.

[0040] Step 102: Determine M groups of sampling points according to the N sampling points; wherein each group of sampling points includes 3 sampling points with equal sampling time intervals, and M is a positive integer.

[0041] In an embodiment of the present application, the steady-state voltage value of the equivalent capacitor can be calculated by the voltage values ​​corresponding to the three sampling points with equal sampling time intervals, wherein the sampling time interval can be a×Δt1, where a is a positive integer. For example, assuming that 10 sampling tasks are executed in sequence to obtain 10 sampling points, these 10 sampling points are recorded as sampling points 1 to 10 in the order of the sampling time corresponding to the sampling points from first to last. Then, in one example, the steady-state voltage value of the equivalent capacitor can be calculated by the voltage values ​​corresponding to sampling points 1 to 3. In this example, the sampling time interval is Δt1. In another example, the steady-state voltage value of the equivalent capacitor can be calculated by sampling points 1, 3 and 5. In this example, the sampling time interval is 2Δt1. In this way, the acquisition of the steady-state voltage does not require delayed waiting, and does not need to rely on the external Y capacitor and the equivalent resistor R, thereby improving the real-time and adaptability of the steady-state voltage acquisition.

[0042] It should be noted that, when N is greater than 3, since the embodiment of the present application can calculate the steady-state voltage value through the voltage values ​​corresponding to the three sampling points with equal sampling time intervals, in some embodiments, step 102 can be executed after sampling to obtain the three sampling points; of course, in other embodiments, step 102 can also be executed after sampling to obtain all N sampling points. The specific decision can be made according to actual needs, and the embodiment of the present application is not limited to this.

[0043] It can be understood that, when N is equal to 3, M is 1; when N is greater than 3, M can be greater than or equal to 1. Further, M can be preset or determined based on actual needs.

[0044] That is to say, when N is greater than 3, the detection device can select one or more groups of 3 sampling points with equal sampling time intervals from the N sampling points, and then use each group of sampling points to determine the steady-state voltage value of an equivalent capacitor, and then finally determine the target steady-state voltage value of the equivalent capacitor based on the steady-state voltage values ​​determined by each group of sampling points.

[0045] It is worth noting that, when N is equal to 3, the detection device can directly determine the target steady-state voltage value of the equivalent capacitor according to the voltage values ​​corresponding to the three sampling points. Therefore, in this case, in some embodiments, the detection device may not need to select sampling points, that is, it is not necessary to perform step 102.

[0046] Step 103: Determine a target steady-state voltage value of the equivalent capacitor according to voltage values ​​corresponding to the sampling points included in the M groups of sampling points.

[0047] When N is equal to 3, the detection device can directly calculate the target steady-state voltage value of the equivalent capacitance based on the three sampling points obtained by sampling.

[0048] In the case where N is greater than 3, if M is equal to 1, the detection device can directly calculate the target steady-state voltage value of the equivalent capacitor according to the voltage values ​​corresponding to the sampling points included in the selected group of sampling points. If M is greater than 1, for each group of sampling points, the steady-state voltage value of the equivalent capacitor corresponding to the group of sampling points can be calculated according to the voltage values ​​corresponding to the sampling points, and then the target steady-state voltage value of the equivalent capacitor is calculated by the steady-state voltage values ​​corresponding to the multiple groups of sampling points.

[0049] Step 104: Determine the insulation resistance of the power supply device to ground according to the target steady-state voltage value.

[0050] For the specific implementation of determining the insulation resistance of the power supply device to the ground based on the target steady-state voltage value of the equivalent capacitance of the power supply device to the ground, please refer to the relevant technology and will not be described here.

[0051] In the insulation resistance detection method of the present embodiment, during the charging or discharging process of the power supply device, the voltage value of the equivalent capacitance of the power supply device to the ground can be sampled at equal time intervals to obtain N sampling points, each sampling point corresponds to a sampling time and a voltage value, and N is an integer greater than 1 or equal to 3. Then, 3 sampling points with equal sampling time intervals are selected from the N sampling points to form a group of sampling points to obtain M groups of sampling points. Afterwards, the target steady-state voltage value of the equivalent capacitance can be determined using the voltage value corresponding to the sampling point of at least one group of sampling points in the M groups of sampling points, and then the insulation resistance of the power supply device to the ground can be obtained. It can be seen that the steady-state voltage can be determined by the voltage value corresponding to the sampling point obtained by sampling at equal time intervals in the embodiment of the present application. In this way, the real-time acquisition of the steady-state voltage can be improved, and the influence of the Y capacitance value and the equivalent resistance R on the determination of the steady-state voltage can be eliminated, thereby improving the real-time and adaptability of the insulation resistance detection.

[0052] In some embodiments, determining the target steady-state voltage value of the equivalent capacitor according to the voltage values ​​corresponding to the sampling points included in the M groups of sampling points may include:

[0053] Obtaining a calculation formula for the steady-state voltage of the equivalent capacitor;

[0054] Determine the steady-state voltage value of the equivalent capacitor corresponding to the target group sampling point according to the steady-state voltage calculation formula and the voltage value corresponding to the sampling point included in the target group sampling point;

[0055] Wherein, the target group of sampling points is any group of sampling points in the M groups of sampling points;

[0056] The steady-state voltage calculation formula is:

[0057] or,

[0058] V end is the steady-state voltage of the equivalent capacitor, V1, V2 and V3 are voltage values ​​corresponding to three sampling points with equal sampling time intervals, and the sampling time of the sampling point corresponding to V1 is before the sampling time of the sampling point corresponding to V2, and the sampling time of the sampling point corresponding to V2 is before the sampling time of the sampling point corresponding to V3.

[0059] In specific implementation, when calculating the steady-state voltage value corresponding to the target group sampling point of the equivalent capacitance, V1 in the steady-state voltage calculation formula can be assigned to the voltage value corresponding to the sampling point with the smallest sampling time among the target group sampling points, V2 can be assigned to the voltage value corresponding to the sampling point with the second smallest sampling time among the target group sampling points, and V3 can be assigned to the voltage value corresponding to the sampling point with the largest sampling time among the target group sampling points. Then, a V can be calculated using the steady-state voltage calculation formula.end , that is, the steady-state voltage value of the equivalent capacitor corresponding to the sampling point of the target group.

[0060] Exemplarily, assuming that the target group sampling points include a first sampling point, a second sampling point, and a third sampling point, wherein a first sampling time corresponding to the first sampling point is before a second sampling time corresponding to the second sampling point, and the second sampling time is before a third sampling time corresponding to the third sampling point. Then, V1 can be assigned the first voltage value corresponding to the first sampling point, V2 can be assigned the second voltage value corresponding to the second sampling point, and V3 can be assigned the third voltage value corresponding to the third sampling point.

[0061] In this embodiment, for each group of sampling points, the equivalent capacitance and the steady-state voltage value corresponding thereto can be calculated based on the voltage values ​​corresponding to the sampling points included therein and the steady-state voltage calculation formula, thereby improving the reliability of determining the steady-state voltage value.

[0062] In some other embodiments, the detection device may pre-store V1, V2, V3 and V end Then, using V1, V2 and V3 corresponding to each sampling point included in each group of sampling points, the above correspondence is searched to obtain the V corresponding to the group of sampling points. end , so we can simplify V end to obtain.

[0063] The embodiments of the present application do not limit the method for obtaining the steady-state voltage calculation formula. In some embodiments, the steady-state voltage calculation formula can be obtained based on a large amount of experimental data. In other embodiments, the steady-state voltage calculation formula for obtaining the equivalent capacitance may include:

[0064] Get the initial capacitance charging and discharging formula;

[0065] Selecting three coordinate points at equal time intervals on a capacitor charging curve or a capacitor discharging curve, each of the coordinate points corresponding to a time and voltage value;

[0066] Substituting the time and voltage values ​​corresponding to the three coordinate points into the capacitance charging and discharging formulas respectively, to obtain three target capacitance charging formulas corresponding to the three coordinate points;

[0067] Determine the time relationship corresponding to the three coordinate points;

[0068] According to the three target capacitance charging formulas and the time relationship formula, a steady-state voltage calculation formula of the equivalent capacitance is determined.

[0069] The initial capacitance charge and discharge formula is a conventional capacitance charge and discharge formula. In this embodiment, the steady-state voltage calculation formula can be derived based on the capacitance charge and discharge formula and the coordinate points of equal time intervals on the capacitance charge and discharge curve, as described below:

[0070] 1) Assume V start is the initial voltage value of the equivalent capacitor; V end V is the voltage value that the equivalent capacitor can finally be charged or discharged to, that is, the steady-state voltage value; t is the voltage value of the equivalent capacitor at time t, R is the equivalent resistance of the power supply device to the ground, and C is the equivalent capacitor, that is, the Y capacitor.

[0071] The initial capacitance charge and discharge formula can be expressed by formula (1) and formula (2):

[0072]

[0073] τ=R*C (2)

[0074] 2) Based on formula (1) and formula (2), formula (3) is derived:

[0075]

[0076] 3) Take three coordinate points with equal time intervals on the capacitance charging curve or capacitance discharging curve of the equivalent capacitance, record them as (t1, V1), (t2, V2), (t3, V3), substitute the three coordinate points into formula (3) to obtain formula (4) to formula (5), and then because the time intervals of the three coordinate points are equal, the time relationship of the three coordinate points can be obtained, that is, formula (6):

[0077]

[0078] t2-t1=t3-t2 (7)

[0079] 4) Combine formula (4) to formula (7) to calculate V end Solving it, we get formula (8):

[0080]

[0081] 5) Since R≠0 and C≠0, then R*C≠0. Divide both sides of formula (8) by R*C to obtain formula (9):

[0082]

[0083] 6) Further assume that V start ≠V end (If V3=V2=V1, then V start =Vend ), solve the exponent ln and get formula (10):

[0084]

[0085] Simplifying formula (10), we get formula (11):

[0086]

[0087] 7) Further solving, because the function y=ln(x) is monotonic, based on formula (11), formula (12) is obtained:

[0088]

[0089] 8) Further assume that V2≠V end , and V3≠V end (If V3=V2, then V end =V3=V2), swap the numerator and denominator on both sides of formula (12) to get formula (13):

[0090] (V1-V end )*(V3-V end )=(V2-V end )*(V2-V end ) (13)

[0091] Based on formula (13), we get formula (14):

[0092] V1*V3-(V1+V3)*V end +(V end ) 2 =(V2) 2 -2*V2*V end +(V end ) 2 (14)

[0093] By swapping the two sides of formula (14) to eliminate the same terms, we get formula (15), and then formula (16):

[0094] 2*V2*V end -(V1+V3)*V end =(V2) 2 -V1*V3 (15)

[0095] (2*V2-(V1+V3))*V end =(V2) 2 -V1*V3 (16)

[0096] Use formula (16) to solve V end, we get the steady-state voltage calculation formula, that is, formula (17) or formula (18)

[0097]

[0098] Among them, 2*V2-(V1+V3)≠0. Take points at equal intervals on the monotonic curve. If 2*V2-(V1+V3)=0, then the curve should be a straight line. However, Figure 2 The capacitor charging curve or capacitor discharging curve shown is not a straight line, so it meets the condition, so that the equivalent voltage value can be calculated using formula (17) or formula (18).

[0099] It can be seen from formula (17) or formula (18) that the equivalent voltage calculation formula is only related to the voltage value corresponding to the sampling point obtained by sampling at equal time intervals, and is independent of the equivalent resistance value R and the equivalent capacitance value C in the circuit. Therefore, it can be applied to the insulation resistance detection of various types of power supply devices, thereby improving the adaptability of insulation resistance detection.

[0100] In this embodiment, the steady-state voltage calculation formula can be derived based on the capacitor charge and discharge formula and the coordinate points of equal time intervals on the capacitor charge and discharge curve, so that the reliability of obtaining the steady-state voltage calculation formula can be improved.

[0101] The sampling task is described in detail below.

[0102] In some embodiments, the voltage value of the equivalent capacitance of the power supply device to the ground is sampled at equal time intervals to obtain N sampling points, which can be specifically expressed as follows:

[0103] At every preset time interval (ie, Δt1), the voltage value of the equivalent capacitance of the power supply device to the ground is sampled once to obtain N sampling points;

[0104] Each of the sampling points corresponds to one sampling, the sampling time corresponding to each of the sampling points is the sampling moment of the one sampling corresponding to the sampling point, and the voltage value corresponding to each of the sampling points is the capacitance value of the equivalent capacitor sampled at the sampling moment.

[0105] In these embodiments, a sampling task may be performed only once. The detection device may perform sampling once every Δt1 to obtain a sampling point. The sampling time corresponding to each sampling point is the sampling time of the corresponding sampling, and the voltage value corresponding to each sampling point is the voltage value of the equivalent capacitor sampled by the corresponding sampling. In this way, the sampling of the voltage value of the equivalent voltage can be simplified.

[0106] In some other embodiments, the voltage value of the equivalent capacitance of the power supply device to the ground is sampled at equal time intervals to obtain N sampling points, which can be specifically expressed as follows:

[0107] At every preset time interval, sampling is performed for a preset time length on the voltage value of the equivalent capacitance of the power supply device to the ground to obtain N sampling points;

[0108] Among them, each sampling point corresponds to a sampling of the preset duration, the sampling time corresponding to each sampling point is the preset duration, and the voltage value corresponding to each sampling point is the average value of the voltage value of the equivalent capacitor sampled within the sampling time corresponding to the sampling point.

[0109] In these embodiments, a sampling task may perform multiple samplings. The detection device may perform sampling for a preset duration (hereinafter referred to as Δt2) at a preset sampling frequency (hereinafter referred to as f) every Δt1 to obtain a sampling point, wherein Δt2 is greater than 2 / f, i.e., it is ensured that at least two samplings can be performed within the preset duration, and Δt2 may be set based on actual needs, and may be in milliseconds, such as 1ms, 5ms, 10ms, 30ms, 50ms, or 100ms.

[0110] The sampling time corresponding to each sampling point can be the sampling time of any sampling of the corresponding sampling task, and the voltage value corresponding to each sampling point can be the average value of the voltage values ​​of multiple equivalent capacitors collected in the corresponding sampling task. For example, assuming that Δt1 is 10s and Δt2 is 30ms, then: every 10s, 30ms of sampling can be performed at a preset frequency, and then the voltage value obtained by 30ms sampling is locally filtered, and the average value of these voltage values ​​is calculated to obtain the voltage value corresponding to each sampling point.

[0111] In this way, each sampling task can implement local filtering of the sampling points by executing sampling for a preset time, thereby increasing external interference resistance and improving the reliability of insulation resistance determination.

[0112] The determination of the target steady-state voltage value when M is greater than 1 is described in detail below.

[0113] In some embodiments, when M is greater than 1, determining the target steady-state voltage value of the equivalent capacitor according to the voltage values ​​corresponding to the sampling points included in the M groups of sampling points includes:

[0114] Sort the M groups of sampling points in ascending order of sampling time;

[0115] According to the order of the M groups of sampling points from first to last, the steady-state voltage value of the equivalent capacitor corresponding to the group of sampling points is determined according to the voltage values ​​corresponding to the sampling points included in each group of sampling points, until the i-th steady-state voltage value of the equivalent capacitor corresponding to the i-th group of sampling points and the i-1-th steady-state voltage value of the equivalent capacitor corresponding to the i-1-th group of sampling points meet a preset condition; wherein the preset condition is that the difference between the i-th steady-state voltage value and the i-1-th steady-state voltage value is less than a first threshold, or the relative change rate between the i-th steady-state voltage value and the i-1-th steady-state voltage value is less than a second threshold; i is a positive integer greater than 1 and less than or equal to M;

[0116] The i-th steady-state voltage value or the (i-1)-th steady-state voltage value is determined as a target steady-state voltage value of the equivalent capacitor.

[0117] It can be understood that different groups of sampling points include at least one different sampling point. The sampling intervals of the sampling points included in different groups of sampling points may be the same or different.

[0118] When the sampling intervals of the sampling points included in different groups of sampling points are equal, the M groups of sampling points can be directly sorted in ascending order of the minimum sampling time.

[0119] In the case where the sampling intervals of the sampling points included in different groups of sampling points are different, considering that the minimum sampling times corresponding to the different groups of sampling points may be equal (for example, assuming that one group of sampling points includes the aforementioned sampling points 1 to sampling point 3, and the other group of sampling points includes the aforementioned sampling point 1, sampling point 3 and sampling point 5), when sorting the M groups of sampling points, the two groups of sampling points can be arbitrarily combined, and the arrangement order of the two groups of sampling points is determined one by one with the two groups of sampling points as units, thereby determining the arrangement order of the M groups of sampling points. For any two groups of sampling points, the sampling points included in each group can be sorted from first to last according to the sampling times corresponding to the sampling points, and then the sampling times corresponding to the two sampling points in the same arrangement order in the two groups of sampling points are compared in turn according to the sorting from first to last, and the first sampling point with unequal sampling times in the two groups of sampling points is found, and then the two groups of sampling points are sorted using the sampling time. For example, for the above two groups of sampling points, the first sampling points with unequal sampling times in the two groups of sampling points are sampling point 2 and sampling point 3. Since the sampling time corresponding to sampling point 2 is before the sampling time corresponding to sampling point 3, it can be determined that the group of sampling points including sampling point 2 is sorted before the group of sampling points including sampling point 3.

[0120] In this embodiment, the steady-state voltage value of the equivalent capacitor corresponding to each group of sampling points may be determined in sequence according to the M groups of sampling points from the earliest to the latest.

[0121] After obtaining two steady-state voltage values, the difference or relative change rate of the two steady-state voltage values ​​can be calculated, and then the difference between the two steady-state voltage values ​​can be compared with a first threshold, or the relative change rate of the two steady-state voltage values ​​can be compared with a second threshold to determine whether the two steady-state voltage values ​​meet a preset condition.

[0122] If the difference between the two steady-state voltage values ​​is less than the first threshold, or the relative change rate of the two steady-state voltage values ​​is less than the second threshold, it means that the two steady-state voltage values ​​are close, and it can be determined that the two steady-state voltage values ​​meet the preset conditions. In this case, any one of the two steady-state voltage values ​​can be directly used as the target steady-state voltage value, or the average of the two steady-state voltage values ​​can be used as the target steady-state voltage. Furthermore, the determination of the steady-state voltage values ​​corresponding to other groups of sampling points can be stopped, so that the operating burden of the detection device can be reduced.

[0123] If the difference between the two steady-state voltage values ​​is greater than or equal to the first threshold, or the relative change rate of the two steady-state voltage values ​​is greater than or equal to the second threshold, it means that the two steady-state voltage values ​​differ greatly, and it can be determined that the two steady-state voltage values ​​do not meet the preset conditions, and the next steady-state voltage value can be determined, and then the last two determined steady-state voltage values ​​are compared as above, and so on, until two steady-state voltage values ​​that meet the preset conditions are determined, and then the target steady-state voltage value is determined based on the two steady-state voltage values, or, the traversal of the M groups of sampling points is completed, and the last determined steady-state voltage value is determined as the target steady-state voltage value.

[0124] In the above manner, as long as two steady-state voltage values ​​that meet the preset conditions are found, the target steady-state voltage value can be determined based on these two steady-state voltage values. In this way, the operating burden of the detection device can be minimized while ensuring the reliability of determining the target steady-state voltage value.

[0125] Of course, in other embodiments, after obtaining the steady-state voltage value corresponding to each group of sampling points, these steady-state voltage values ​​can be averaged to obtain the target steady-state voltage value, which can be determined according to actual needs and is not limited in this embodiment of the present application.

[0126] It should be noted that the various optional implementation modes introduced in the embodiments of the present application can be implemented in combination with each other or separately if they do not conflict with each other, and the embodiments of the present application are not limited to this.

[0127] Based on the insulation resistance detection method provided in the above embodiment, the present application also provides a specific implementation of an insulation resistance detection device. Please refer to the following embodiment.

[0128] See also Figure 3, the insulation resistance detection device provided in the embodiment of the present application may include:

[0129] The sampling module 301 is used to sample the voltage value of the equivalent capacitance of the power supply device to the ground at equal time intervals during the charging or discharging process of the power supply device to obtain N sampling points; wherein each sampling point corresponds to a sampling time and a voltage value, and N is an integer greater than or equal to 3;

[0130] A first determination module 302 is configured to select M groups of sampling points from the N sampling points; wherein each group of sampling points includes three sampling points with equal sampling time intervals among the N sampling points, and M is a positive integer;

[0131] A second determination module 303, configured to determine a target steady-state voltage value of the equivalent capacitor according to voltage values ​​corresponding to the sampling points included in the M groups of sampling points;

[0132] The third determination module 304 is used to determine the insulation resistance of the power supply device to the ground according to the target steady-state voltage value.

[0133] The insulation resistance detection device provided in the embodiment of the present application can implement each process implemented by the insulation resistance detection device in the method embodiment, and will not be described again here to avoid repetition.

[0134] Figure 4 A schematic diagram of the hardware structure of insulation resistance detection provided in an embodiment of the present application is shown.

[0135] The insulation resistance detection device may include a processor 401 and a memory 402 storing computer program instructions.

[0136] Specifically, the processor 401 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0137] Memory 402 may include a large capacity memory for data or instructions. By way of example and not limitation, memory 402 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, memory 402 may include a removable or non-removable (or fixed) medium. In appropriate cases, memory 402 may be inside or outside of an integrated gateway disaster recovery device. In a specific embodiment, memory 402 is a non-volatile solid-state memory.

[0138] The memory may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Therefore, generally, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the method according to one aspect of the present disclosure.

[0139] The processor 401 implements any one of the insulation resistance detection methods in the above embodiments by reading and executing computer program instructions stored in the memory 402 .

[0140] In one example, the insulation resistance detection device may further include a communication interface 404 and a bus 410. Figure 4 As shown, the processor 401, the memory 402, and the communication interface 404 are connected via a bus 410 and communicate with each other.

[0141] The communication interface 404 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0142] Bus 410 includes hardware, software or both, and the components of the insulation resistance detection device are coupled to each other. For example, but not limitation, the bus may include Accelerated Graphics Port (AGP) or other graphics bus, Enhanced Industry Standard Architecture (EISA) bus, Front Side Bus (FSB), Hyper Transport (HT) interconnection, Industry Standard Architecture (ISA) bus, InfiniBand interconnection, Low Pin Count (LPC) bus, Memory bus, Micro Channel Architecture (MCA) bus, Peripheral Component Interconnect (PCI) bus, Serial Advanced Technology Attachment (SATA) bus, Video Electronics Standards Association Local Bus (VLB) bus or other suitable bus or two or more of these combinations. In appropriate cases, bus 410 may include one or more buses. Although the present application embodiment describes and shows a specific bus, the present application considers any suitable bus or interconnection.

[0143] In addition, in combination with the insulation resistance detection method in the above embodiment, the embodiment of the present application can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by a processor, any insulation resistance detection method in the above embodiment is implemented.

[0144] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0145] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM, floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0146] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0147] Aspects of the present disclosure are described above with reference to the flowchart and / or block diagram of the method, device (system) and computer program product according to the embodiment of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the function / action specified in one or more boxes of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit. It can also be understood that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can also be implemented by dedicated hardware that performs a specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions.

[0148] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A method for detecting insulation resistance, characterized in that: include: During the charging or discharging process of the power supply device, the voltage value of the equivalent capacitance of the power supply device to the ground is sampled at equal time intervals to obtain N sampling points; wherein each sampling point corresponds to a sampling time and a voltage value, and N is an integer greater than or equal to 3; Selecting M groups of sampling points from the N sampling points; wherein each group of sampling points includes 3 sampling points with equal sampling time intervals among the N sampling points, and M is a positive integer; Determining a target steady-state voltage value of the equivalent capacitor according to voltage values ​​corresponding to the sampling points included in the M groups of sampling points; The insulation resistance of the power supply device to ground is determined according to the target steady-state voltage value.

2. The method according to claim 1, characterized in that The step of determining the target steady-state voltage value of the equivalent capacitor according to the voltage values ​​corresponding to the sampling points included in the M groups of sampling points includes: Obtaining a steady-state voltage calculation formula for the equivalent capacitor; Determine the steady-state voltage value of the equivalent capacitor corresponding to the target group sampling point according to the steady-state voltage calculation formula and the voltage value corresponding to the sampling point included in the target group sampling point; Wherein, the target group of sampling points is any group of sampling points in the M groups of sampling points; The steady-state voltage calculation formula is: V end is the steady-state voltage of the equivalent capacitor, V1, V2 and V3 are voltage values ​​corresponding to three sampling points with equal sampling time intervals, and the sampling time of the sampling point corresponding to V1 is before the sampling time of the sampling point corresponding to V2, and the sampling time of the sampling point corresponding to V2 is before the sampling time of the sampling point corresponding to V3.

3. The method according to claim 2, characterized in that The calculation formula for obtaining the steady-state voltage of the equivalent capacitor includes: Get the initial capacitance charging and discharging formula; Selecting three coordinate points at equal time intervals on a capacitor charging curve or a capacitor discharging curve, each of the coordinate points corresponding to a time and voltage value; Substituting the time and voltage values ​​corresponding to the three coordinate points into the capacitance charging and discharging formulas respectively, to obtain three target capacitance charging formulas corresponding to the three coordinate points; Determine the time relationship corresponding to the three coordinate points; According to the three target capacitance charging formulas and the time relationship formula, a steady-state voltage calculation formula of the equivalent capacitance is determined.

4. The method according to claim 1, characterized in that: The step of sampling the voltage value of the equivalent capacitance of the power supply device to the ground at equal time intervals to obtain N sampling points includes: At every preset time interval, sampling is performed once on the voltage value of the equivalent capacitance of the power supply device to the ground to obtain N sampling points; Each of the sampling points corresponds to one sampling, the sampling time corresponding to each of the sampling points is the sampling moment of the one sampling corresponding to the sampling point, and the voltage value corresponding to each of the sampling points is the capacitance value of the equivalent capacitor sampled at the sampling moment.

5. The method according to claim 1, characterized in that The step of sampling the voltage value of the equivalent capacitance of the power supply device to the ground at equal time intervals to obtain N sampling points includes: At every preset time interval, sampling is performed for a preset time length on the voltage value of the equivalent capacitance of the power supply device to the ground to obtain N sampling points; Among them, each sampling point corresponds to a sampling of the preset duration, the sampling time corresponding to each sampling point is the preset duration, and the voltage value corresponding to each sampling point is the average value of the voltage value of the equivalent capacitor sampled within the sampling time corresponding to the sampling point.

6. The method according to claim 1, characterized in that When M is greater than 1, determining the target steady-state voltage value of the equivalent capacitor according to the voltage values ​​corresponding to the sampling points included in the M groups of sampling points includes: Sort the M groups of sampling points in ascending order of sampling time; According to the order of the M groups of sampling points from first to last, the steady-state voltage value of the equivalent capacitor corresponding to the group of sampling points is determined according to the voltage values ​​corresponding to the sampling points included in each group of sampling points, until the i-th steady-state voltage value of the equivalent capacitor corresponding to the i-th group of sampling points and the i-1-th steady-state voltage value of the equivalent capacitor corresponding to the i-1-th group of sampling points meet a preset condition; wherein the preset condition is that the difference between the i-th steady-state voltage value and the i-1-th steady-state voltage value is less than a first threshold, or the relative change rate between the i-th steady-state voltage value and the i-1-th steady-state voltage value is less than a second threshold; i is a positive integer greater than 1 and less than or equal to M; The i-th steady-state voltage value or the (i-1)-th steady-state voltage value is determined as a target steady-state voltage value of the equivalent capacitor.

7. An insulation resistance detection device, characterized in that: include: A sampling module, used to sample the voltage value of the equivalent capacitance of the power supply device to the ground at equal time intervals during the charging or discharging process of the power supply device, to obtain N sampling points; wherein each of the sampling points corresponds to a sampling time and a voltage value, and N is an integer greater than or equal to 3; A first determination module is used to select M groups of sampling points from the N sampling points; wherein each group of sampling points includes 3 sampling points with equal sampling time intervals among the N sampling points, and M is a positive integer; A second determination module, configured to determine a target steady-state voltage value of the equivalent capacitor according to voltage values ​​corresponding to the sampling points included in the M groups of sampling points; The third determination module is used to determine the insulation resistance of the power supply device to the ground according to the target steady-state voltage value.

8. An insulation resistance detection device, characterized in that: The device comprises: a processor and a memory storing computer program instructions; when the processor executes the computer program instructions, the insulation resistance detection method according to any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the insulation resistance detection method according to any one of claims 1 to 6 is implemented.

10. A computer program product, characterized in that When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the insulation resistance detection method according to any one of claims 1 to 6.

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