A dynamic insulation detection method and device, a storage medium and an electronic device

Abstract

The application discloses a kind of dynamic insulation detection method, device, storage medium and electronic equipment, the method comprises: obtaining bridge arm voltage and total voltage after main positive switch is closed or main negative switch is closed for a preset time;According to whether the change value of bridge arm voltage in any adjacent sampling period in preset sampling period is less than the first preset value, judge whether bridge arm voltage is stable;According to the difference between the maximum value, minimum value and average value of total voltage in each insulation detection period unilaterally period, judge whether total voltage is stable;When bridge arm voltage is stable and / or total voltage is stable, calculate insulation resistance according to bridge arm voltage and total voltage.By implementing the present application, the bridge arm voltage and total voltage after the main positive switch is closed or the main negative switch is closed for a preset time are obtained, the stability of the bridge arm voltage and the total voltage is judged, and the insulation resistance is calculated only when the total voltage fluctuation meets the condition or the bridge arm voltage is stable, thereby improving the stability, accuracy and reliability of the calculated insulation resistance.

Description

Technical Field

[0001] This invention relates to the field of high-voltage electrical testing technology in new energy vehicles, specifically to a dynamic insulation testing method, device, storage medium, and electronic equipment. Background Technology

[0002] In the battery management system of new energy vehicles, two important functions require special consideration and design due to their connection to personal safety. The first is high-voltage detection, and the second is PACK insulation resistance detection. Because the voltage of the power battery in an electric vehicle can reach over 500V, contact with it could endanger human life. Therefore, the insulation between the power battery and the vehicle is extremely important.

[0003] High-voltage detection involves monitoring the input voltage of the power battery. The system needs to monitor the voltage at different locations within the vehicle's high-voltage electrical system in real time to determine the system's operating status, and especially to take appropriate measures to bring the vehicle to a safe state in case of a fault. Currently, these high-voltage detection methods generally employ a resistor network for pre-division voltage measurement, followed by analog-to-digital (AD) sampling conversion. Considering the high voltage, high-resistance resistors should be selected for the voltage divider, and multiple resistors should be connected in series. This reduces the voltage across a single resistor and improves circuit reliability.

[0004] Regarding insulation resistance testing, national standards stipulate minimum requirements for the insulation of the entire vehicle. Furthermore, during the design process, insulation parameters must have a safety margin to ensure that insulation measures do not fail due to aging throughout the component's lifespan. The primary purpose of insulation resistance testing is to measure the insulation resistance between the positive and negative terminals of the high-voltage battery and the vehicle chassis. Current insulation resistance testing methods mainly include the balanced bridge method, the unbalanced bridge method, the AC injection method, and the current sensing method.

[0005] When using the balanced bridge method for testing, an external resistor needs to be connected. This external resistor changes the equivalent circuit of the current insulation circuit, resulting in a problem that the insulation resistance value calculated using the current bridge arm voltage is less accurate. Summary of the Invention

[0006] In view of this, embodiments of the present invention provide a dynamic insulation detection method, apparatus, storage medium, and electronic device to solve the technical problem of poor accuracy when using the balanced bridge method to detect insulation resistance in the prior art.

[0007] The technical solution proposed in this invention is as follows:

[0008] The first aspect of this invention provides a dynamic insulation detection method, comprising: acquiring the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch; determining whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within a preset sampling period is less than a first preset value; determining whether the total voltage is stable based on the difference between the maximum value, minimum value and average value of the total voltage in a single period of each insulation detection period; and calculating the insulation resistance based on the bridge arm voltage and total voltage after the bridge arm voltage and / or the total voltage are stable.

[0009] Optionally, obtaining the bridge arm voltage and total voltage after a preset time following the closing of the main positive switch or the closing of the main negative switch includes: obtaining the positive bridge arm voltage and total voltage after a preset time following the closing of the main positive switch and the opening of the main negative switch; obtaining the negative bridge arm voltage and total voltage after a preset time following the closing of the main negative switch and the opening of the main positive switch.

[0010] Optionally, determining whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within the preset sampling period is less than a preset value includes: determining whether the change value of the bridge arm voltage in any adjacent sampling period within the preset sampling period is less than a first preset value; when it is less than the preset value, performing window filtering on the bridge arm voltage; during the window filtering period, continuing to determine whether the change value of the bridge arm voltage in any adjacent sampling period is less than the first preset value; when it is less than the preset value, determining that the bridge arm voltage is stable.

[0011] Optionally, after determining whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within the preset sampling period is less than a preset value, the method further includes: acquiring the positive bridge arm voltage determined in two adjacent insulation detection periods; determining whether the difference between the two positive bridge arm voltages is less than a second preset value; when it is less than the second preset value, calculating the insulation resistance value based on the positive bridge arm voltage determined in the later insulation detection period and the negative bridge arm voltage determined in the previous insulation detection period; when it is not less than the second preset value, continuing to acquire the positive bridge arm voltage determined in the next insulation detection period and the difference judgment in the previous insulation detection period, until it is less than the second preset value.

[0012] Optionally, the dynamic insulation detection method further includes: acquiring the negative bridge arm voltage determined by two adjacent insulation detection cycles; determining whether the difference between the two negative bridge arm voltages is less than a second preset value; when it is less than the second preset value, calculating the insulation resistance value based on the negative bridge arm voltage determined by the later insulation detection cycle and the positive bridge arm voltage determined by the corresponding cycle; when it is not less than the second preset value, continuing to acquire the negative bridge arm voltage determined by the next insulation detection cycle and judging the difference with the previous insulation detection cycle, until it is less than the second preset value.

[0013] Optionally, determining whether the total voltage is stable based on the difference between the maximum, minimum, and average values ​​of the total voltage in a single-sided cycle of each insulation detection cycle includes: obtaining the first maximum, first minimum, and first average value of the total voltage when the main positive switch is closed; obtaining the second maximum, second minimum, and second average value of the total voltage when the main negative switch is closed; and determining whether the total voltage is stable based on the difference between the first maximum and first minimum values, the difference between the second maximum and second minimum values, and the difference between the first average value and the second average value.

[0014] Optionally, after the bridge arm voltage stabilizes and / or the total voltage stabilizes, the insulation resistance is calculated based on the bridge arm voltage and the total voltage, including: after the bridge arm voltage stabilizes, determining the stable bridge arm voltage based on the average value of the bridge arm voltage over a preset sampling period after window filtering; after the total voltage stabilizes, determining the stable total voltage based on the average value of the total voltage over a preset sampling period; and calculating the insulation resistance based on the bridge arm voltage and the total voltage.

[0015] A second aspect of this invention provides a dynamic insulation detection device, comprising: a voltage acquisition module for acquiring the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch; a first stability judgment module for determining whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within a preset sampling period is less than a first preset value; a second stability judgment module for determining whether the total voltage is stable based on the difference between the maximum value, minimum value, and average value of the total voltage in a single-sided period of each insulation detection period; and a calculation module for calculating the insulation resistance based on the bridge arm voltage and total voltage after the bridge arm voltage and / or the total voltage are stable.

[0016] A third aspect of the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to perform the dynamic insulation detection method as described in the first aspect and any one of the first aspects of the present invention.

[0017] A fourth aspect of the present invention provides an electronic device, including: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the dynamic insulation detection method as described in the first aspect and any one of the first aspects of the present invention.

[0018] The technical solution provided by this invention has the following effects:

[0019] The dynamic insulation detection method, device, storage medium, and electronic device provided in this invention obtain the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch, and then determine the stability of the bridge arm voltage and total voltage. The insulation resistance is calculated only when the total voltage fluctuation meets the conditions or the bridge arm voltage is stable, thereby avoiding the calculation of incorrect resistance values ​​and improving the stability, accuracy, and reliability of the calculated insulation resistance values. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a flowchart of a dynamic insulation detection method according to an embodiment of the present invention;

[0022] Figure 2 This is an insulation detection circuit diagram of the dynamic insulation detection method according to an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the detection process of the dynamic insulation detection method according to an embodiment of the present invention;

[0024] Figure 4 This is a flowchart of a dynamic insulation detection method according to another embodiment of the present invention;

[0025] Figure 5 This is a structural block diagram of a dynamic insulation detection device according to an embodiment of the present invention;

[0026] Figure 6 This is a schematic diagram of the structure of a computer-readable storage medium provided according to an embodiment of the present invention;

[0027] Figure 7 This is a schematic diagram of the structure of an electronic device provided according to an embodiment of the present invention. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0029] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] As described in the background section, the current method of insulation resistance testing using the balanced bridge method suffers from inaccurate calculations of the insulation resistance. Specifically, when using the balanced bridge method, a large detection resistor needs to be connected in parallel with both the positive insulation resistance (RP) and the negative insulation resistance (RN). When the insulation resistance of one side decreases, the voltage on that side is rapidly pulled down, thus detecting the fault and the resistance value.

[0031] However, the connection of an external sensing resistor alters the equivalent circuit of the current insulation loop, affecting the voltage division ratio of the positive and negative bridge arms. The bridge arm voltages require time to reach a stable state again. Therefore, if testing is performed directly after connecting the sensing resistor, the unstable bridge arm voltages will cause insulation resistance jumps. Furthermore, due to the long insulation period, fluctuations in the total voltage during this period will affect the insulation bridge arm voltages. Thus, at low resistance values, these fluctuations in total voltage can lead to significant deviations in insulation accuracy.

[0032] Furthermore, during the insulation accuracy testing of the entire package or vehicle, the errors acquired by the ADC and the presence of zero drift can also cause the calculated insulation resistance value to be positively biased.

[0033] In view of this, embodiments of the present invention provide a dynamic insulation detection method, which solves the problem of unstable insulation resistance calculation caused by unstable bridge arm voltage or large fluctuations in total voltage by determining a stable bridge arm voltage or total voltage.

[0034] According to an embodiment of the present invention, a dynamic insulation detection method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0035] This embodiment provides a dynamic insulation detection method, which can be used in electronic devices such as computers, mobile phones, and tablets. Figure 1 This is a flowchart of a dynamic insulation detection method according to an embodiment of the present invention, such as... Figure 1 As shown, the method includes the following steps:

[0036] Step S101: Obtain the bridge arm voltage and total voltage after a preset time following the closing of the main positive switch or the main negative switch;

[0037] Specifically, such as Figure 2 The diagram shown is a circuit diagram for insulation resistance testing using the balanced bridge method. Where R... p R represents the positive electrode insulation resistance. n C represents the insulation resistance of the negative electrode. p and C n R is the parasitic capacitance in the circuit. a and R b The input resistors are the detection resistors. Switch1 to Switch4 are switches. Switch1 is the main positive switch, Switch2 is the main negative switch, and Switch3 and Switch4 are auxiliary switches. By opening the auxiliary switches, Yb and Yc can be connected to the circuit. Vmsr_p represents the voltage sampling point of the main positive switch bridge arm, and Vmsr_n represents the voltage sampling point of the main negative switch bridge arm.

[0038] In the process of insulation resistance detection and calculation, generally, an insulation resistance calculation needs to be performed after each insulation detection cycle. An insulation detection cycle includes two single-sided cycles. In the first single-sided cycle, by controlling the main positive switch to close and the main negative switch to open, a stable bridge arm voltage and total voltage are obtained. In the second single-sided cycle, the main positive switch opens and the main negative switch closes, obtaining a stable bridge arm voltage and total voltage. Furthermore, the first and second single-sided cycles can be interchanged, i.e., the main negative switch can be closed first, followed by the main negative switch. This embodiment of the invention does not specifically limit this.

[0039] In this embodiment, each insulation detection cycle is 10 seconds, and a single-sided cycle is 5 seconds. Each insulation cycle can also be other times, and this embodiment of the invention does not limit this. Within each single-sided cycle, the bridge arm voltage and total voltage need to be sampled and recorded based on the sampling period. That is, the bridge arm voltage is collected and recorded once every sampling cycle, thus obtaining multiple bridge arm voltages and total voltages within each single-sided cycle. In this embodiment, the sampling period is 20 ms, but it can also be other times, as long as it is shorter than the single-sided cycle.

[0040] In one embodiment, when the single-sided period is 5s and the sampling period is 20ms, in the first insulation detection period, that is, when the insulation resistance is calculated for the first time, the bridge arm voltage and total voltage are not sampled in the first 3s before the main positive switch or the main negative switch is closed, and sampling is performed after 3s, so as to avoid circuit instability when power is started.

[0041] Step S102: Determine whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within the preset sampling period is less than the first preset value.

[0042] Specifically, taking the bridge arm voltage collected when the main positive switch is closed and the positive and negative switches are open as an example, we will explain the bridge arm voltage stability judgment. After the main positive switch is closed for a preset time, such as 3 seconds after closing, the bridge arm voltage is sampled for a preset sampling period. Then, the difference between the bridge arm voltages of adjacent sampling periods is calculated to determine whether the change value of the adjacent bridge arm voltage is less than the preset value, thereby judging the stability of the bridge arm voltage within a single period.

[0043] The same method can be used to determine the bridge arm voltage when the main negative switch is closed and the main positive switch is open, which will not be elaborated here. Furthermore, it should be noted that if the bridge arm voltage is determined to be unstable in one single-sided cycle, an insulation detection cycle must be completed, and the insulation resistance calculation should only be triggered after the bridge arm voltage has stabilized in both single-sided cycles.

[0044] Step S103: Determine whether the total voltage is stable based on the difference between the maximum, minimum, and average values ​​of the total voltage in each single-sided cycle of the insulation detection cycle. Specifically, in each single-sided cycle, after a preset time following the closure of the main positive switch or the main negative switch, the total voltage is sampled according to the sampling period to obtain multiple total voltages. For example, in each single-sided cycle, 3 seconds after the closure of the main positive switch or the main negative switch, 100 total voltages are sampled at a sampling interval of 20ms. The maximum, minimum, and average values ​​of the 100 total voltages are calculated, and then the stability of the total voltage is determined based on the difference between these values.

[0045] Step S104: Once the bridge arm voltage and / or the total voltage are stable, calculate the insulation resistance based on the bridge arm voltage and the total voltage. Specifically, within one insulation testing cycle, if the bridge arm voltage or the total voltage is determined to be stable through the above steps, the insulation resistance can be calculated using the stable bridge arm voltage and the total voltage. The specific insulation resistance calculation process can employ the existing balanced bridge method, which will not be elaborated upon here.

[0046] The dynamic insulation detection method provided in this invention obtains the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch, and then judges the stability of the bridge arm voltage and total voltage. The insulation resistance is calculated only when the total voltage fluctuation meets the conditions or the bridge arm voltage is stable, thereby avoiding the calculation of incorrect resistance values ​​and improving the stability, accuracy and reliability of the calculated insulation resistance value.

[0047] In one embodiment, determining whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within a preset sampling period is less than a preset value includes: determining whether the change value of the bridge arm voltage in any adjacent sampling period within a preset sampling period is less than a first preset value; when it is less than the preset value, performing window filtering on the bridge arm voltage; during the window filtering period, continuing to determine whether the change value of the bridge arm voltage in any adjacent sampling period is less than the first preset value; when it is less than the preset value, determining that the bridge arm voltage is stable.

[0048] like Figure 3 As shown, specifically, when judging the stability of the bridge arm voltage within a single-sided cycle, after the main positive or negative switch is closed for 3 seconds, the bridge arm voltage value is continuously sampled for multiple sampling cycles, such as 25 sampling cycles. Then, the difference between the bridge arm voltages of any two adjacent sampling cycles is calculated, and it is determined whether the difference is less than a first preset value, such as whether it is less than 5mV. If all differences are less than the first preset value, window filtering of the sampled bridge arm voltage is started. During the window filtering period, the bridge arm voltage is sampled again, and the change value of the bridge arm voltage is judged. If the change value of the bridge arm voltage is not less than the first preset value at any time after the main positive or negative switch is closed for 3 seconds, the bridge arm voltage is resampled for 25 sampling cycles for judgment. If the bridge arm voltage is not stable at the end of a single-sided cycle, insulation calculation is not performed.

[0049] In one embodiment, after determining whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within a preset sampling period is less than a preset value, the method further includes: acquiring the positive bridge arm voltage determined in two adjacent insulation detection periods; determining whether the difference between the two positive bridge arm voltages is less than a second preset value; when it is less than the second preset value, calculating the insulation resistance value based on the positive bridge arm voltage determined in the later insulation detection period and the negative bridge arm voltage determined in the previous insulation detection period; when it is not less than the second preset value, continuing to acquire the positive bridge arm voltage determined in the next insulation detection period and the difference judgment in the previous insulation detection period, until it is less than the second preset value.

[0050] Specifically, during the first insulation detection cycle after power-on, once the bridge arm voltage is determined to be stable using the above method, the insulation resistance can be calculated. Simultaneously, the bridge arm voltage Vp1 when the main positive switch is closed and the bridge arm voltage Vn1 when the main negative switch is closed, obtained during the first insulation detection cycle, are obtained. Then, the second insulation detection cycle begins. The positive bridge arm voltage Vp1 when the main positive switch is closed and the negative bridge arm voltage Vn1 when the main negative switch is closed, when the bridge arm voltage is stable, can be obtained by averaging multiple window-filtered bridge arm voltages within the last preset time period of a single-sided cycle. For example, the average calculation can be performed on 15 window-filtered bridge arm voltages within the last 300ms of a 5s single-sided cycle.

[0051] Therefore, in the second insulation detection cycle, within the single-sided cycle of the main positive switch closing and the main negative switch closing, the average of multiple bridge arm voltages filtered by the window within the last preset time of the single-sided cycle is taken to obtain the positive bridge arm voltage Vp2. Then, the difference between this positive bridge arm voltage Vp2 and the positive bridge arm voltage Vp1 in the previous insulation detection cycle is calculated, and it is determined whether the difference is less than a second preset value, such as whether it is less than 50mV. If it is less, it is considered that the insulation resistance value in this cycle has not changed much from the resistance in the previous cycle, and the insulation resistance value can be calculated and updated using Vp2 and Vn1, and Vp2 is recorded. If the difference is not less than the second preset value, it is considered that the insulation resistance value in this cycle has changed significantly from the resistance or total voltage in the previous cycle, and the insulation resistance is not calculated in this case, and Vp2 is recorded. Then, the positive bridge arm voltage is calculated in the next insulation detection cycle, and it is determined whether the difference between the two positive bridge arm voltages meets the condition. When the condition is met, the insulation resistance is calculated.

[0052] In one embodiment, the dynamic insulation detection method further includes: acquiring the negative bridge arm voltage determined by two adjacent insulation detection cycles; determining whether the difference between the two negative bridge arm voltages is less than a second preset value; when it is less than the second preset value, calculating the insulation resistance value based on the negative bridge arm voltage determined by the later insulation detection cycle and the positive bridge arm voltage determined by the corresponding cycle; when it is not less than the second preset value, continuing to acquire the negative bridge arm voltage determined by the next insulation detection cycle and the difference judgment by the previous insulation detection cycle, until it is less than the second preset value.

[0053] Specifically, after determining that the positive arm voltage meets the condition during the second insulation detection cycle, the negative arm voltage Vn2 is obtained by calculating the average value of multiple filtered arm voltages within the last preset time period during the single-sided cycle of the negative switch closing and the main positive switch closing. Then, in the same way, it is determined whether the difference between the negative arm voltage Vn2 and the negative arm voltage Vn1 meets the condition. If the condition is met, the insulation resistance is calculated based on the positive arm voltage Vp2 and the negative arm voltage Vn2.

[0054] In one embodiment, determining whether the total voltage is stable based on the difference between the maximum, minimum, and average values ​​of the total voltage in a single-sided cycle of each insulation detection cycle includes: obtaining the first maximum, first minimum, and first average value of the total voltage when the main positive switch is closed; obtaining the second maximum, second minimum, and second average value of the total voltage when the main negative switch is closed; and determining whether the total voltage is stable based on the difference between the first maximum and first minimum values, the difference between the second maximum and second minimum values, and the difference between the first average value and the second average value.

[0055] Specifically, the total voltage is recorded starting from the 3rd second of each single-sided cycle (5s) and ending at the end of the cycle. When the main positive switch is closed, the maximum value Vpack_PosMax, minimum value Vpack_PosMin, and average value Vpack_PosAvg of the total voltage in that interval are recorded; when the negative bridge arm is closed, the maximum value Vpack_NegMax, minimum value Vpack_NegMin, and average value Vpack_NegAvg of the total voltage in that interval are recorded; simultaneously, the average values ​​Vpack_PosAvgF and Vpack_NegAvgF of the total voltage in the last 15 sampling cycles (300ms) of each single side are calculated. When judging the total voltage, if |Vpack_PosMax - Vpack_PosMin| >= 10V or |Vpack_NegMax - Vpack_NegMin| >= 10V (or other values), then the total voltage fluctuation is considered large. Meanwhile, if |Vpack_PosAvg - Vpack_NegAvg| >= 5V (or other values), then the total voltage fluctuation is considered large. When the total voltage fluctuation is large, insulation resistance is not calculated.

[0056] In one embodiment, after the bridge arm voltage stabilizes and / or the total voltage stabilizes, the insulation resistance is calculated based on the bridge arm voltage and the total voltage, including: after the bridge arm voltage stabilizes, determining the stable bridge arm voltage based on the average value of the bridge arm voltage over a preset sampling period after window filtering; after the total voltage stabilizes, determining the stable total voltage based on the average value of the total voltage over a preset sampling period; and calculating the insulation resistance based on the bridge arm voltage and the total voltage.

[0057] Specifically, within each insulation detection cycle, if the bridge arm voltage of each single-sided cycle is determined to be stable, the average of multiple bridge arm voltages filtered through a window within the last preset time period of each single-sided cycle is taken to obtain the bridge arm voltage of the corresponding single-sided cycle. Simultaneously, when the total voltage is determined to be stable, the average of multiple total voltages within the last preset time period of each single-sided cycle can also be obtained to obtain the total voltage of the current single-sided cycle. The preset time period can be the last 15 sampling cycles in a single-sided cycle.

[0058] In one implementation, such as Figure 4 As shown, the dynamic insulation testing method is implemented using the following process:

[0059] After BMS initialization is complete, insulation resistance detection begins. If activation fails, insulation detection stops and an insulation detection fault is reported. Upon successful activation, insulation resistance is calculated by closing either the main positive or negative switch. Simultaneously, when closing the main positive or negative switch, auxiliary switches can also be closed as needed.

[0060] The determination of bridge arm voltage is illustrated using the closure of the main positive switch as an example. After the main positive switch closes and the main negative switch opens, a stability assessment of the positive bridge arm voltage is performed after a 3-second wait. The voltage variation of adjacent bridge arms within 25 consecutive sampling periods is continuously checked to see if it is less than 5mV (to be calibrated; other preset values ​​can also be used). If this condition is met, the sampled bridge arm voltage is window-filtered, and the stability assessment continues during the filtering period. If the stability requirement is not met, insulation calculation is not performed, and the previous calculated value is retained. Furthermore, to facilitate subsequent insulation resistance calculations, the average of the latest 15 filtered bridge arm voltage values ​​is calculated to obtain the stable positive bridge arm voltage Vp1 and negative bridge arm voltage Vn1.

[0061] Then, in the next insulation detection cycle, the positive bridge arm voltage Vp2 is calculated by analyzing the windowed bridge arm voltages. The insulation resistance is then calculated based on whether the difference between the positive bridge arm voltage Vp1 and the positive bridge arm voltage Vp2 of the next insulation detection cycle is less than 50mV. The same judgment is then made based on the negative bridge arm voltage Vn2. When both the positive and negative bridge arm voltages meet the conditions, Vp2 and Vn2 for the current cycle are obtained. This completes the bridge arm voltage judgment process.

[0062] To determine the total voltage, the total voltage can be recorded starting from the 3rd second of each single-sided cycle (5s) until the end of the cycle. When the main positive switch is closed, record the maximum value Vpack_PosMax, minimum value Vpack_PosMin, and average value Vpack_PosAvg of the total voltage in that interval; when the negative bridge arm is closed, record the maximum value Vpack_NegMax, minimum value Vpack_NegMin, and average value Vpack_NegAvg of the total voltage in that interval; simultaneously calculate the average values ​​Vpack_PosAvgF and Vpack_NegAvgF of the total voltage in the last 15 sampling cycles (300ms) of each single side. When determining the total voltage, if |Vpack_PosMax - Vpack_PosMin| >= 10V or |Vpack_NegMax - Vpack_NegMin| >= 10V (or other values), then the total voltage fluctuation is considered large. Meanwhile, if |Vpack_PosAvg - Vpack_NegAvg| >= 5V (or other values), then the total voltage fluctuation is considered large. When the total voltage fluctuation is large, insulation resistance is not calculated. Then, based on the total voltage satisfying |Vpack_PosMax - Vpack_PosMin| < 10V and |Vpack_NegMax - Vpack_NegMin| < 10V, and |Vpack_PosAvg - Vpack_NegAvg| < 5V, it is filtered and used as the parameter for calculating the insulation resistance.

[0063] The filtered positive and negative bridge arm voltages and the total voltage are substituted into the insulation calculation formula to calculate the insulation resistance. The insulation resistance is then continuously updated.

[0064] In one embodiment, to demonstrate the detection effect of the dynamic insulation detection method of the present invention, simulation tests can be conducted under the same operating conditions with different resistances. Specifically, when the negative electrode is set to 50kΩ, the static result calculated using existing methods is 45kΩ, and the maximum dynamic insulation resistance is 72kΩ, with a minimum of 28kΩ; while using the detection method of the present invention, the calculated static result is 43kΩ, and the maximum dynamic insulation resistance is 51kΩ, with a minimum of 37kΩ. When the negative electrode is set to 100kΩ, the static result calculated using existing methods is 91kΩ, and the maximum dynamic insulation resistance is 117kΩ, with a minimum of 75kΩ; while using the detection method of the present invention, the calculated static result is 89kΩ, and the maximum dynamic insulation resistance is 98kΩ, with a minimum of 83kΩ. When the negative electrode is set to 500kΩ, the static result calculated using existing methods is 450kΩ, and the maximum dynamic insulation resistance is 480kΩ, with a minimum of 435kΩ; while using the detection method of the present invention, the calculated static result is 448kΩ, and the maximum dynamic insulation resistance is 458kΩ, with a minimum of 439kΩ.

[0065] In addition, a static comparison can be performed. In this case, the total voltage is set to be stable, and the positive electrode resistance is set sequentially as follows: 1000kΩ → 200kΩ → 200kΩ → 50kΩ → 50kΩ → 20kΩ → 20kΩ → 0kΩ. If the existing method is used for detection, the calculated resistance is sequentially as follows: 965kΩ → 33kΩ → 193kΩ → 10kΩ → 50kΩ → 16kΩ → 22kΩ → 2kΩ. If the method of this invention is used for detection, the calculated resistance is sequentially as follows: 916kΩ → 916kΩ → 183kΩ → 185kΩ → 45kΩ → 12kΩ → 17kΩ → 0kΩ.

[0066] Since the total voltage under dynamic operating conditions with low resistance has a relatively large impact on the insulation resistance, when the dynamic insulation detection method of the present invention is used for dynamic simulation testing, the interference from the total voltage fluctuation is greatly reduced, and the fluctuation range of the insulation resistance is significantly narrowed.

[0067] This invention also provides a dynamic insulation detection device, such as... Figure 5 As shown, the device includes:

[0068] The voltage acquisition module is used to acquire the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch; for details, please refer to the corresponding part of the above method embodiment, which will not be repeated here.

[0069] The first stability judgment module is used to determine whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within the preset sampling period is less than the first preset value; for details, please refer to the corresponding part of the above method embodiment, which will not be repeated here.

[0070] The second stability judgment module is used to determine whether the total voltage is stable based on the difference between the maximum, minimum and average values ​​of the total voltage in a single-sided period of each insulation detection cycle; for details, please refer to the corresponding part of the above method embodiment, which will not be repeated here.

[0071] The calculation module is used to calculate the insulation resistance based on the bridge arm voltage and / or the total voltage after the bridge arm voltage has stabilized and / or the total voltage has stabilized. For details, please refer to the corresponding sections of the above method embodiments, which will not be repeated here.

[0072] The dynamic insulation detection device provided in this embodiment of the invention acquires the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch, and judges the stability of the bridge arm voltage and total voltage. The insulation resistance is calculated only when the total voltage fluctuation meets the conditions or the bridge arm voltage is stable, thereby avoiding the calculation of incorrect resistance values ​​and improving the stability, accuracy and reliability of the calculated insulation resistance value.

[0073] For a detailed description of the function of the dynamic insulation detection device provided in this embodiment of the invention, please refer to the description of the dynamic insulation detection method in the above embodiments.

[0074] This invention also provides a storage medium, such as... Figure 6 As shown, a computer program 601 is stored on it. When executed by a processor, this program implements the steps of the dynamic insulation detection method described in the above embodiments. The storage medium also stores audio and video stream data, feature frame data, interactive request signaling, encrypted data, and a preset data size. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium may also include combinations of the above types of memory.

[0075] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium can also include combinations of the above types of memory.

[0076] This invention also provides an electronic device, such as... Figure 7 As shown, the electronic device may include a processor 51 and a memory 52, wherein the processor 51 and the memory 52 may be connected via a bus or other means. Figure 7 Taking the example of a connection between China and Israel via a bus.

[0077] Processor 51 can be a central processing unit (CPU). Processor 51 can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above types of chips.

[0078] The memory 52, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the corresponding program instructions / modules in the embodiments of the present invention. The processor 51 executes various functional applications and data processing of the processor by running the non-transitory software programs, instructions, and modules stored in the memory 52, thereby implementing the dynamic insulation detection method in the above method embodiments.

[0079] The memory 52 may include a program storage area and a data storage area. The program storage area may store applications required for operating the device and at least one function; the data storage area may store data created by the processor 51, etc. Furthermore, the memory 52 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 52 may optionally include memory remotely located relative to the processor 51, and these remote memories may be connected to the processor 51 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0080] The one or more modules are stored in the memory 52, and when executed by the processor 51, they perform the following: Figure 1 The dynamic insulation detection method in the embodiment shown in Figure 4.

[0081] For specific details regarding the aforementioned electronic devices, please refer to the relevant documentation. Figures 1 to 4 The relevant descriptions and effects in the illustrated embodiments are for understanding purposes only and will not be repeated here.

[0082] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A dynamic insulation testing method, characterized in that, include: Within an insulation detection cycle, acquire the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch. Whether the bridge arm voltage is stable is determined by whether the change value of the bridge arm voltage in any adjacent sampling period within the preset sampling period is less than the first preset value. When the bridge arm voltage is stable, the average value of multiple bridge arm voltages filtered by the window in the last preset time of the single-sided cycle is taken to obtain the positive bridge arm voltage and the negative bridge arm voltage. The stability of the total voltage is determined by the difference between the maximum, minimum and average values ​​of the total voltage in each single-sided cycle of the insulation test cycle. Once the bridge arm voltage and / or the total voltage are stable, calculate the insulation resistance based on the bridge arm voltage and the total voltage. After determining whether the bridge arm voltage is stable based on whether the change in bridge arm voltage in any adjacent sampling period within the preset sampling period is less than the preset value, the following steps are also included: Obtain the positive bridge arm voltage determined by two adjacent insulation detection cycles; Determine whether the difference between the voltages of the two positive bridge arms is less than a second preset value; When it is less than the second preset value, the insulation resistance value is calculated based on the positive bridge arm voltage determined in the later insulation detection cycle and the negative bridge arm voltage determined in the previous insulation detection cycle. When the voltage is not less than the second preset value, continue to obtain the positive bridge arm voltage determined in the next insulation detection cycle and the difference between the voltage in the previous insulation detection cycle until it is less than the second preset value. An insulation detection cycle includes two single-sided cycles; acquiring the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch, including: Within one single-sided cycle of the insulation detection cycle, acquire the positive bridge arm voltage and total voltage after the main positive switch closes and the main negative switch opens for a preset time; During another single-sided cycle of the insulation detection cycle, the negative bridge arm voltage and total voltage are acquired after the main negative switch is closed and the main positive switch is opened for a preset time.

2. The dynamic insulation testing method according to claim 1, characterized in that, The stability of the bridge arm voltage is determined by whether the change in bridge arm voltage between any two adjacent sampling periods within a preset sampling period is less than a preset value, including: Determine whether the change in bridge arm voltage between any two adjacent sampling periods within a preset sampling period is less than a first preset value; When the voltage is less than the preset value, the bridge arm voltage is window-filtered. During window filtering, it continues to determine whether the change in bridge arm voltage in any adjacent sampling period is less than a first preset value; When the voltage is less than the preset value, the bridge arm voltage is considered stable.

3. The dynamic insulation testing method according to claim 1, characterized in that, Also includes: Obtain the negative bridge arm voltage determined by two adjacent insulation detection cycles; Determine whether the difference between the voltages of the two negative bridge arms is less than a second preset value; When it is less than the second preset value, the insulation resistance value is calculated based on the negative bridge arm voltage determined in the latter insulation detection cycle of the two negative bridge arm voltages and the positive bridge arm voltage determined in the corresponding cycle. If the voltage is not less than the second preset value, continue to obtain the negative bridge arm voltage determined in the next insulation detection cycle and compare it with the voltage in the previous insulation detection cycle to determine the difference, until it is less than the second preset value.

4. The dynamic insulation testing method according to claim 1, characterized in that, The stability of the total voltage is determined by the difference between the maximum, minimum, and average values ​​of the total voltage in each single-sided cycle of the insulation test cycle, including: Obtain the first maximum value, first minimum value, and first average value of the total voltage when the main positive switch is closed; Obtain the second maximum value, second minimum value, and second average value of the total voltage when the main negative switch is closed; The stability of the total voltage is determined by the difference between the first maximum and the first minimum, the difference between the second maximum and the second minimum, and the difference between the first average and the second average.

5. The dynamic insulation testing method according to claim 1, characterized in that, Once the bridge arm voltage and / or the total voltage have stabilized, calculate the insulation resistance based on the bridge arm voltage and the total voltage, including: Once the bridge arm voltage stabilizes, the stable bridge arm voltage is determined based on the average value of the bridge arm voltage over the preset sampling period after window filtering. Once the total voltage stabilizes, the stable total voltage is determined based on the average value of the total voltage over the preset sampling period. Calculate the insulation resistance based on the bridge arm voltage and the total voltage.

6. A dynamic insulation detection device, characterized in that, include: The voltage acquisition module is used to acquire the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch within one insulation detection cycle. The first stability judgment module is used to determine whether the bridge arm voltage is stable based on whether the change value of the bridge arm voltage in any adjacent sampling period within the preset sampling period is less than the first preset value. The bridge arm voltage determination module is used to obtain the positive bridge arm voltage and the negative bridge arm voltage by averaging multiple bridge arm voltages filtered by a window during the last preset time in a single cycle when the bridge arm voltage is stable. The second stability judgment module is used to determine whether the total voltage is stable based on the difference between the maximum, minimum and average values ​​of the total voltage in a single-sided period of each insulation detection cycle. The calculation module is used to calculate the insulation resistance based on the bridge arm voltage and the total voltage after the bridge arm voltage stabilizes and / or the total voltage stabilizes. After determining whether the bridge arm voltage is stable based on whether the change in bridge arm voltage in any adjacent sampling period within the preset sampling period is less than the preset value, the following steps are also included: Obtain the positive bridge arm voltage determined by two adjacent insulation detection cycles; Determine whether the difference between the voltages of the two positive bridge arms is less than a second preset value; When it is less than the second preset value, the insulation resistance value is calculated based on the positive bridge arm voltage determined in the later insulation detection cycle and the negative bridge arm voltage determined in the previous insulation detection cycle. When the voltage is not less than the second preset value, continue to obtain the positive bridge arm voltage determined in the next insulation detection cycle and the difference between the voltage in the previous insulation detection cycle until it is less than the second preset value. An insulation detection cycle includes two single-sided cycles; acquiring the bridge arm voltage and total voltage after a preset time following the closure of the main positive switch or the main negative switch, including: Within one single-sided cycle of the insulation detection cycle, acquire the positive bridge arm voltage and total voltage after the main positive switch closes and the main negative switch opens for a preset time; During another single-sided cycle of the insulation detection cycle, the negative bridge arm voltage and total voltage are acquired after the main negative switch is closed and the main positive switch is opened for a preset time.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the dynamic insulation detection method as described in any one of claims 1-5.

8. An electronic device, characterized in that, include: The system includes a memory and a processor, which are communicatively connected to each other. The memory stores computer instructions, and the processor executes the computer instructions to perform the dynamic insulation detection method as described in any one of claims 1-5.

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