Time constant determination method and insulation detection control method

Abstract

The embodiment of the invention discloses a time constant determination method and an insulation detection control method. The time constant determination method is applied to the insulation detection circuit, and comprises the following steps: receiving a control instruction; according to the control instruction, controlling the first insulation switch to be closed, and obtaining an insulation voltage when the first insulation switch is closed and insulation voltages at at least two different preset times after the first insulation switch is closed; determining a first time constant according to the insulation voltage when the first insulation switch is closed and the insulation voltages of at least two different preset times after the first insulation switch is closed; controlling the second insulation switch to be closed, and obtaining the insulation voltage when the second insulation switch is closed and the insulation voltage of at least two different preset times after the second insulation switch is closed; and determining a second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltages of at least two different preset times after the second insulation switch is closed. According to the time constant determination method and the insulation detection control method provided by the embodiment of the invention, the insulation detection efficiency can be improved.

Description

Technical Field

[0001] The embodiments of the present invention relate to insulation detection technology, and in particular to a method for determining a time constant and a method for controlling insulation detection. Background Art

[0002] For scenarios with insulation requirements, such as the high-voltage part of electric vehicles, its insulation strength affects the safety of the entire vehicle. The high-voltage part of an electric vehicle mainly includes batteries and charging and discharging circuits, and the battery shell is connected to the vehicle body ground (body shell). In order to ensure the safety of people in the car, good insulation performance is required between the high-voltage part and the vehicle body ground. However, the high-voltage part of an electric vehicle is subject to changes in working conditions, vibration, temperature, humidity, etc., which may cause changes in the insulation strength of the high-voltage part. Reduced insulation strength may endanger the personal safety of drivers and passengers. Therefore, it is necessary to perform insulation testing on the high-voltage part including the battery. In insulation testing, the time constant is an important part that affects the efficiency of insulation testing, and the size of the time constant needs to be determined. Summary of the invention

[0003] The embodiment of the present invention provides a method for determining a time constant and a method for controlling insulation detection, so as to improve the efficiency of insulation detection.

[0004] In a first aspect, an embodiment of the present invention provides a method for determining a time constant, which is applied to an insulation detection circuit, wherein the insulation detection circuit includes a first insulation resistor, a second insulation resistor, a first insulation switch, a second insulation switch, a first series resistor, a second series resistor, a first capacitor, and a second capacitor; the first insulation switch is connected in series with the first series resistor and then connected in parallel with the first capacitor, the first capacitor is connected in parallel with the first insulation resistor, the second insulation switch is connected in series with the second series resistor and then connected in parallel with the second capacitor, the second capacitor is connected in parallel with the second insulation resistor, the two ends of the first insulation resistor are respectively connected to the positive electrode of the battery and the ground, and the two ends of the second insulation resistor are respectively connected to the negative electrode of the battery and the ground; the method for determining the time constant includes:

[0005] Receive control instructions;

[0006] According to the control instruction, the first insulating switch is controlled to close, and an insulating voltage when the first insulating switch is closed and an insulating voltage at at least two different preset times after closing are obtained; the insulating voltage is the first capacitor voltage or the second capacitor voltage;

[0007] determining a first time constant according to the insulation voltage when the first insulation switch is closed and the insulation voltages at at least two different preset times after closing;

[0008] Controlling the second insulating switch to close, and obtaining the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing;

[0009] The second time constant is determined according to the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing.

[0010] Optionally, the obtaining of the insulation voltage when the first insulating switch is closed and the insulation voltages at at least two different preset times after closing includes:

[0011] The insulation voltage when the first insulating switch is closed and the insulation voltage when it is closed for t seconds and k1t seconds are obtained, where k1 is a number greater than 1.

[0012] Optionally, determining the first time constant according to the insulation voltage when the first insulation switch is closed and the insulation voltages at at least two different preset times after closing includes:

[0013] According to the insulation voltage U0 when the first insulating switch is closed and the insulation voltage U0 t seconds after closing t And the insulation voltage U when closed k1t seconds k1t , determine U k1t -U0 and U t -U0 ratio, k1 is a number greater than 1;

[0014] A first time constant τ1 is determined according to the ratio.

[0015] Optionally, the first time constant is τ1, (U k1t -U0) / (U t -U0)=(1-e -k1t / τ1 ) / (1-e -t / τ1 ), where U k1t is the insulation voltage when the first insulating switch is closed for k1t seconds, U0 is the insulation voltage when the first insulating switch is closed, and U t is the insulation voltage when the first insulating switch is closed for t seconds, and k1 is a number greater than 1.

[0016] Optionally, determining the second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing includes:

[0017] According to the insulation voltage U0′ when the second insulating switch is closed and the insulation voltage U0′ t seconds after closing t ' and the insulation voltage U when closed for k2t seconds k2t ′, determine U k2t ′-U0′ and U t′-U0′ ratio, k2 is a number greater than 1;

[0018] A second time constant τ2 is determined based on the ratio.

[0019] Optionally, the second time constant is τ2, (U k2t ′-U0′) / (U t ′-U0′)=(1-e -k1t / τ2 ) / (1-e -t / τ2 ), where U k2t ' is the insulation voltage when the second insulating switch is closed for k2t seconds, U0' is the insulation voltage when the second insulating switch is closed, U t ' is the insulation voltage when the second insulating switch is closed for t seconds, and k2 is a number greater than 1.

[0020] In a second aspect, an embodiment of the present invention provides a control method for insulation detection, which is applied to an insulation detection circuit, wherein the insulation detection circuit includes a first insulation resistor, a second insulation resistor, a first insulation switch, a second insulation switch, a first series resistor, a second series resistor, a first capacitor, and a second capacitor; the first insulation switch is connected in series with the first series resistor and then connected in parallel with the first capacitor, the first capacitor is connected in parallel with the first insulation resistor, the second insulation switch is connected in series with the second series resistor and then connected in parallel with the second capacitor, the second capacitor is connected in parallel with the second insulation resistor, the two ends of the first insulation resistor are respectively connected to the positive electrode of the battery and the ground, and the two ends of the second insulation resistor are respectively connected to the negative electrode of the battery and the ground; the control method for insulation detection includes:

[0021] Receive control instructions;

[0022] According to the control instruction, the first insulating switch is controlled to close, and an insulating voltage when the first insulating switch is closed and an insulating voltage at at least two different preset times after closing are obtained; the insulating voltage is the first capacitor voltage or the second capacitor voltage;

[0023] determining a first time constant according to the insulation voltage when the first insulation switch is closed and the insulation voltages at at least two different preset times after closing;

[0024] Determining a first group of insulation sampling voltages according to the first time constant;

[0025] Controlling the second insulating switch to close, and obtaining the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing;

[0026] determining a second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing;

[0027] Determine a second set of insulation sampling voltages according to the second time constant;

[0028] Determine the resistance values of the first insulation resistor and the second insulation resistor according to the first set of insulation sampling voltages and the second set of insulation sampling voltages.

[0029] Optionally, the determining the first set of insulation sampling voltages according to the first time constant includes:

[0030] When the first insulation switch is closed for k3τ1, determine the voltage of the first insulation switch and the voltage of the second insulation switch at this time as the first set of insulation sampling voltages; τ1 is the first time constant, k3 is a number greater than 0, and the range where k3 is located is 4.5 - 5.5.

[0031] Optionally, the resistance values of the first insulation resistor and the second insulation resistor are calculated by the formulas V1 / (R1 / / R A ) = V2 / R2 and V1' / R1 = V2' / (R2 / / R B ), where R A is the resistance value of the first series resistor, R B is the resistance value of the second series resistor, R1 is the resistance value of the first insulation resistor, R2 is the resistance value of the second insulation resistor, V1 is the voltage of the first insulation resistor when the first insulation switch is closed, V2 is the voltage of the second insulation resistor when the first insulation switch is closed, V1' is the voltage of the first insulation resistor when the second insulation switch is closed, and V2' is the voltage of the second insulation resistor when the second insulation switch is closed.

[0032] Optionally, after determining the second set of insulation sampling voltages, it includes:

[0033] Control the first insulation switch to close and the second insulation switch to close in a loop at preset intervals to perform a loop detection on the resistance values of the first insulation resistor and the second insulation resistor.

[0034] The embodiment of the present invention provides a method for determining a time constant and a method for controlling insulation detection. The method for determining a time constant is applied to an insulation detection circuit. The insulation detection circuit includes a first insulation resistor, a second insulation resistor, a first insulation switch, a second insulation switch, a first series resistor, a second series resistor, a first capacitor, and a second capacitor; the first insulation switch is connected in series with the first series resistor and then connected in parallel with the first capacitor, the first capacitor is connected in parallel with the first insulation resistor, the second insulation switch is connected in series with the second series resistor and then connected in parallel with the second capacitor, the second capacitor is connected in parallel with the second insulation resistor, the two ends of the first insulation resistor are respectively connected to the positive electrode of the battery and the ground, and the two ends of the second insulation resistor are respectively connected to the negative electrode of the battery and the ground; the time constant The method for determining a time constant comprises: receiving a control instruction; according to the control instruction, controlling the first insulating switch to close, and obtaining the insulation voltage when the first insulating switch is closed and the insulation voltage at least two different preset times after closing; the insulation voltage is the first capacitor voltage or the second capacitor voltage; determining the first time constant according to the insulation voltage when the first insulating switch is closed and the insulation voltage at at least two different preset times after closing; controlling the second insulating switch to close, and obtaining the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing; determining the second time constant according to the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing. The method for determining a time constant and the method for controlling insulation detection provided by the embodiment of the present invention determine the first time constant according to the insulation voltage when the first insulating switch is closed and the insulation voltage at at least two different preset times after closing, and determine the second time constant according to the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing, so as to perform insulation detection on the insulation detection circuit according to the first time constant and the second time constant. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flow chart of a method for determining a time constant provided in Embodiment 1 of the present invention;

[0036] Figure 2 is a schematic diagram of an insulation detection circuit provided in Embodiment 1 of the present invention;

[0037] Figure 3 is a flow chart of a method for determining a time constant provided in Embodiment 2 of the present invention;

[0038] Figure 4 is a flow chart of a control method for insulation detection provided by Embodiment 3 of the present invention;

[0039] Figure 5 A device for determining a time constant provided by a fourth embodiment of the present invention;

[0040] Figure 6A control device for insulation detection provided by a fourth embodiment of the present invention;

[0041] Figure 7 It is a structural schematic diagram of an electronic device provided in Embodiment 5 of the present invention. DETAILED DESCRIPTION

[0042] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0043] Embodiment 1

[0044] Figure 1 is a flow chart of a method for determining a time constant provided in Embodiment 1 of the present invention, Figure 2 Schematic diagram of an insulation detection circuit provided by Embodiment 1 of the present invention. Figure 1 and Figure 2 The method for determining the time constant is applied to an insulation detection circuit, and the insulation detection circuit includes a first insulation resistor R1, a second insulation resistor R2, a first insulation switch K1, a second insulation switch K2, a first series resistor RA, a second series resistor RB, a first capacitor C1, and a second capacitor C2; the first insulation switch K1 is connected in series with the first series resistor RA and then connected in parallel with the first capacitor C1, the first capacitor C1 is connected in parallel with the first insulation resistor R1, the second insulation switch K2 is connected in series with the second series resistor RB and then connected in parallel with the second capacitor C2, the second capacitor C2 is connected in parallel with the second insulation resistor R2, the two ends of the first insulation resistor R1 are respectively connected to the positive electrode V+ of the battery and the ground, and the two ends of the second insulation resistor R2 are respectively connected to the negative electrode V- of the battery and the ground. This embodiment can be applied to aspects such as determining the time constant of the insulation detection circuit. The method can be executed by a device for determining the time constant, which can be integrated in an electronic device such as a computer, and the device can be implemented in the form of software and / or hardware. The method specifically includes the following steps:

[0045] Step 110: Receive control instructions.

[0046] The control instruction may include a control instruction for controlling the closing of the insulating switch.

[0047] Step 120: According to the control instruction, the first insulating switch is controlled to close, and the insulating voltage when the first insulating switch is closed and the insulating voltage at at least two different preset times after closing are obtained; the insulating voltage is the first capacitor voltage or the second capacitor voltage.

[0048] Specifically, when a control instruction is received, the first insulating switch is controlled to close, and the insulating voltage U0 when the first insulating switch is closed and the insulating voltage U0 t seconds after the first insulating switch is closed are obtained. t And the insulation voltage U when closed k1t (k1 is greater than 1) seconds k1t . Exemplarily, t ranges from 1.5-3.

[0049] Step 130: Determine a first time constant according to the insulation voltage when the first insulation switch is closed and the insulation voltages at at least two different preset times after closing.

[0050] Among them, the first time constant is about U k1t -U0 and U t -U0 is the exponential function of the ratio.

[0051] Step 140: Control the second insulating switch to close, and obtain the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing.

[0052] Specifically, after obtaining the insulation voltages at at least two different preset times after the second insulation switch is closed, the second insulation switch is controlled to close, and the insulation voltage U0′ at this time and the insulation voltage U0′ t seconds after the second insulation switch is closed are obtained. t ' and the insulation voltage U when closed k2t (k2 is greater than 1) seconds k2t ′.

[0053] Step 150: Determine a second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing.

[0054] When the second insulating switch is closed, the first insulating switch is opened, and when the first insulating switch is closed, the second insulating switch is opened. The second time constant is about U k2t ′-U0′ and U t The exponential function of the ratio of ′-U0′.

[0055] It should be noted that, in addition to Figure 1 In addition to the process steps shown in the figure, the order of some steps is not limited and can be adjusted as needed; for example, combining Figure 1 Steps 140 and 150 may be executed sequentially first, and then steps 120 and 130 may be executed sequentially; steps 120 and 140 may be executed sequentially first, and then steps 130 and 150 may be executed sequentially, and so on. That is, relevant data may be obtained first to calculate the first time constant, and then the data may be obtained to determine the second time constant. Alternatively, all the data may be obtained first and then the two time constants may be determined (calculated) sequentially / simultaneously. The specific time constants may be determined according to actual test requirements and are not limited here.

[0056] The method for determining the time constant provided in this embodiment determines the first time constant based on the insulation voltage when the first insulation switch is closed and the insulation voltages at at least two different preset times after closing, and determines the second time constant based on the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing. There is no need to determine the time constant when the first capacitor or the second capacitor is about to be fully charged, thereby reducing the waiting time for insulation detection and improving the efficiency of insulation detection.

[0057] Embodiment 2

[0058] Figure 3 : is a flow chart of a method for determining a time constant provided in the second embodiment of the present invention. The method for determining a time constant is applied to an insulation detection circuit. The specific structure of the insulation detection circuit is shown in FIG. Figure 2 This embodiment can be applied to aspects such as determining a time constant of an insulation detection circuit. The method can be executed by a time constant determination device, which can be integrated in an electronic device such as a computer. The device can be implemented in the form of software and / or hardware. The method specifically includes the following steps:

[0059] Step 210: Receive control instructions.

[0060] The control instruction may include a control instruction for controlling the closing of the insulating switch.

[0061] Step 220: According to the control instruction, the first insulating switch is controlled to close, and the insulating voltage when the first insulating switch is closed and the insulating voltage when it is closed for t seconds and k1t seconds are obtained, where k1 is a number greater than 1.

[0062] The insulation voltage is the first capacitor voltage or the second capacitor voltage, and the first capacitor voltage or the second capacitor voltage can be acquired by a voltage sensor.

[0063] Step 230: according to the insulation voltage U0 when the first insulating switch is closed and the insulation voltage U0 t seconds after closing t And the insulation voltage U when closed k1t seconds k1t , determine U k1t -U0 and U t -U0 ratio, k1 is a number greater than 1.

[0064] Step 240: Determine a first time constant τ1 according to the ratio.

[0065] Exemplarily, when the first insulating switch is closed, the first capacitor voltage is U0, and the first capacitor voltages when the first insulating switch is closed for t seconds and k1t seconds are U t and U k1t According to the charge and discharge characteristics of the capacitor, U t-U0=(U1-U0)*(1-e -t / τ1 ), U k1t -U0=(U1-U0)*(1-e -k1t / τ1 ), the above two equations are divided to obtain (U k1t -U0) / (U t -U0)=(1-e -k1t / τ1 ) / (1-e -t / τ1 ), where U k1t is the insulation voltage when the first insulating switch is closed for k1t seconds, U0 is the insulation voltage when the first insulating switch is closed, U t is the insulation voltage when the first insulation switch is closed for t seconds, U1 is the voltage value that the first capacitor can finally be charged or discharged, k1 is a number greater than 1, and the first time constant τ1 can be obtained from the above formula. When k1 is 2, the above formula can be simplified to (U 2t -U0) / (U t -U0)=1+e -t / τ1 .

[0066] Step 250: Control the second insulating switch to close, and obtain the insulation voltage when the second insulating switch is closed and the insulation voltage when it is closed for t seconds and k2t seconds, where k2 is a number greater than 1.

[0067] Step 260: according to the insulation voltage U0′ when the second insulating switch is closed and the insulation voltage U0′ t seconds after closing, t ' and the insulation voltage U when closed for k2t seconds k2t ′, determine U k2t ′-U0′ and U t The ratio of ′-U0′.

[0068] Step 270: Determine a second time constant τ2 according to the ratio.

[0069] Exemplarily, when the second insulating switch is closed, the second capacitor voltage is U0′, and the second capacitor voltages when the second insulating switch is closed for t seconds and k2t seconds are U t ′ and U k2t ′, according to the charge and discharge characteristics of the capacitor, U t ′-U0′=(U1′-U0′)*(1-e -t / τ1 ), U k2t ′-U0′=(U1′-U0′)*(1-e -k1t / τ1 ), the above two equations are divided to obtain (U k2t ′-U0′) / (U t ′-U0′)=(1-e -k1t / τ2 ) / (1-e -t / τ2 ), where U k2t′ is the insulation voltage when the second insulating switch is closed for k2t seconds, U0′ is the insulation voltage when the second insulating switch is closed, U t ' is the insulation voltage when the second insulation switch is closed for t seconds, U1' is the voltage value that the second capacitor can finally be charged or discharged, and k2 is a number greater than 1. When k2 is 2, the above formula can be simplified to (U 2t -U0) / (U t -U0)=1+e -t / τ2 .

[0070] Furthermore, the voltage in the above-mentioned first time constant τ1 calculation formula is the voltage of the first capacitor and is only for schematic illustration, and may also be the voltage of the second capacitor. The voltage in the second time constant τ2 calculation formula is the voltage of the second capacitor and is only for schematic illustration, and may also be the voltage of the first capacitor, which is not limited here.

[0071] It should be noted that, in addition to Figure 3 In addition to the process steps shown in the figure, the order of some steps is not limited and can be adjusted as needed; for example, combining Figure 3 Steps 250, 260, and 270 may be executed sequentially first, and then steps 220, 230, and 240 may be executed sequentially; steps 220, 230, and 240 may be executed sequentially first, and then steps 250, 260, and 270 may be executed sequentially, and so on. That is, relevant data may be obtained first to calculate the first time constant, and then the data may be obtained to determine the second time constant. Alternatively, all the data may be obtained first and then the two time constants may be determined (calculated) sequentially / simultaneously. The specific time constants may be determined according to actual test requirements and are not limited here.

[0072] The method for determining the time constant provided in this embodiment determines the first time constant based on the insulation voltage when the first insulation switch is closed and the insulation voltage when it is closed for t seconds and k1t seconds, and determines the second time constant based on the insulation voltage when the second insulation switch is closed and the insulation voltage when it is closed for t seconds and k2t seconds. There is no need to determine the time constant when the first capacitor or the second capacitor is about to be fully charged, thereby reducing the waiting time for insulation detection and improving the efficiency of insulation detection.

[0073] Embodiment 3

[0074] Figure 4 Flow chart of a control method for insulation detection provided by Embodiment 3 of the present invention. This embodiment can be applied to insulation detection of an insulation detection circuit. The specific structure of the insulation detection circuit is shown in FIG. Figure 2 The method can be performed by a control device for insulation detection, which can be integrated in an electronic device such as a computer, and can be implemented in the form of software and / or hardware. The method specifically includes the following steps:

[0075] Step 310: Receive a control instruction.

[0076] Step 320: According to the control instruction, control the first insulation switch to close, and obtain the insulation voltage when the first insulation switch closes and the insulation voltages at at least two different preset times after closing; the insulation voltage is the first capacitor voltage or the second capacitor voltage.

[0077] Step 330: Determine the first time constant according to the insulation voltage when the first insulation switch closes and the insulation voltages at at least two different preset times after closing.

[0078] Step 340: Determine the first set of insulation sampling voltages according to the first time constant.

[0079] Specifically, when the first insulation switch closes at k3τ1, determine the voltage of the first insulation switch and the voltage of the second insulation switch at this time as the first set of insulation sampling voltages; τ1 is the first time constant, k3 is a number greater than 0, and the range where k3 is located is 4.5 - 5.5.

[0080] Step 350: Control the second insulation switch to close, and obtain the insulation voltage when the second insulation switch closes and the insulation voltages at at least two different preset times after closing.

[0081] Step 360: Determine the second time constant according to the insulation voltage when the second insulation switch closes and the insulation voltages at at least two different preset times after closing.

[0082] Among them, the specific determination process of the first time constant and the second time constant can refer to any of the above embodiments, and will not be elaborated here.

[0083] Step 370: Determine the second set of insulation sampling voltages according to the second time constant.

[0084] Specifically, when the second insulation switch closes at k4τ2, determine the voltage of the first insulation switch and the voltage of the second insulation switch at this time as the second set of insulation sampling voltages; τ2 is the second time constant, k4 is a number greater than 0, and the range where k4 is located is 4.5 - 5.5.

[0085] Step 380: Determine the resistance value of the first insulation resistor and the resistance value of the second insulation resistor according to the first set of insulation sampling voltages and the second set of insulation sampling voltages.

[0086] Specifically, the resistance value of the first insulation resistor and the resistance value of the second insulation resistor are calculated by the formulas V1 / (R1 / / R A )=V2 / R2 and V1′ / R1=V2′ / (R2 / / R B ) where, R1 is the resistance value of the first insulation resistor, R2 is the resistance value of the second insulation resistor, R Ais the resistance of the first series resistor, R B is the resistance value of the second series resistor, V1 is the voltage of the first insulation resistor when the first insulation switch is closed, V2 is the voltage of the second insulation resistor when the first insulation switch is closed, V1′ is the voltage of the first insulation resistor when the second insulation switch is closed, V2′ is the voltage of the second insulation resistor when the second insulation switch is closed, R1 / / R A Represents the resistance value of the first insulation resistor connected in parallel with the first series resistor, R2 / / R B Indicates the resistance of the second insulation resistor connected in parallel with the second series resistor. If the resistance of the first insulation resistor and the resistance of the second insulation resistor are both higher than the preset value, it is determined that the insulation performance of the battery connected to the first insulation resistor and the second insulation resistor is good; if the resistance of the first insulation resistor and / or the resistance of the second insulation resistor is lower than the preset value, it is determined that the battery has an insulation problem.

[0087] In addition, after the second insulating switch is controlled to be closed, the first insulating switch and the second insulating switch are controlled to be closed cyclically at every preset interval, so as to perform cyclic detection on the resistance value of the first insulation resistor and the resistance value of the second insulation resistor. Specifically, the first insulating switch is controlled to be closed at a preset interval after the second insulating switch is closed (to obtain the insulation voltage at least two different preset times after the first insulating switch is closed, determine the first time constant, and determine the first group of insulation sampling voltages by the first time constant), and the second insulating switch is controlled to be closed at a preset interval after the first insulating switch is closed (to obtain the insulation voltage at least two different preset times after the second insulating switch is closed, determine the second time constant, and determine the second group of insulation sampling voltages by the second time constant), so as to cyclically control the on and off of the two insulating switches to achieve continuity of insulation detection.

[0088] It should be noted that, in addition to Figure 4 In addition to obtaining the first time constant and the second time constant by using the process steps shown in the figure, the order of some steps is not limited. For details, please refer to the description of the above-mentioned embodiment 1, which will not be repeated here. Moreover, similar to embodiments 1 and 2, the order of the steps in this embodiment does not necessarily correspond to the order in the flowchart, and the order requirements for obtaining the time constant in embodiments 1 and 2 and obtaining the resistance value in embodiment 3 are different. For example, for the calculation of the time constant, in embodiments 1 and 2, the insulation switch can be closed successively to obtain the insulation voltage, and then the time constant is calculated respectively according to the insulation voltage; but for the calculation of the insulation resistance, since the two groups of insulation voltages must use the time constant, a certain time constant must be calculated first, and then the value is used to obtain the insulation voltage of the corresponding group before the other insulation switch can be closed and the corresponding data can be obtained.

[0089] The insulation detection control method provided in this embodiment belongs to the same inventive concept as the time constant determination method provided in any embodiment of the present invention, and has corresponding beneficial effects. For technical details not detailed in this embodiment, please refer to the time constant determination method provided in any embodiment of the present invention.

[0090] Embodiment 4

[0091] Figure 5 This is a time constant determination device provided by the fourth embodiment of the present invention. The time constant determination device is applied to the insulation detection circuit. The specific structure of the insulation detection circuit can be referred to Figure 2 The above description of the structure of the insulation detection circuit will not be repeated here. Figure 5 The device for determining the time constant includes: an instruction receiving module 511, a first control module 521, a first determining module 531, a second control module 522, and a second determining module 532. The instruction receiving module 511 is used to receive a control instruction; the first control module 521 is used to control the first insulating switch to close according to the control instruction, and obtain the insulation voltage when the first insulating switch is closed and the insulation voltage at least two different preset times after closing; the insulation voltage is the first capacitor voltage or the second capacitor voltage; the first determining module 531 is used to determine the first time constant according to the insulation voltage when the first insulating switch is closed and the insulation voltage at at least two different preset times after closing; the second control module 522 is used to control the second insulating switch to close, and obtain the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing; the second determining module 532 is used to determine the second time constant according to the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing.

[0092] Figure 6 The present invention provides a control device for insulation detection according to the fourth embodiment. The control device for insulation detection is applied to the above insulation detection circuit; Figure 6The control device for insulation detection includes: an instruction receiving module 511, a first control module 521, a first determining module 531, a third determining module 533, a second control module 522, a second determining module 532, a fourth determining module 534 and a fifth determining module 535; wherein the instruction receiving module 511 is used to receive a control instruction; the first control module 521 is used to control the first insulation switch to close according to the control instruction, and obtain the insulation voltage when the first insulation switch is closed and the insulation voltage at least two different preset times after closing; the insulation voltage is the first capacitor voltage or the second capacitor voltage; the first determining module 531 is used to determine the insulation voltage when the first insulation switch is closed and the insulation voltage at at least two different preset times after closing according to the insulation voltage when the first insulation switch is closed and the insulation voltage at at least two different preset times after closing voltage, and determines the first time constant; the third determination module 533 is used to determine the first group of insulation sampling voltages according to the first time constant; the second control module 522 is used to control the second insulation switch to close, and obtain the insulation voltage when the second insulation switch is closed and the insulation voltages at least two different preset times after closing; the second determination module 532 is used to determine the second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing; the fourth determination module 534 is used to determine the second group of insulation sampling voltages according to the second time constant; the fifth determination module 535 is used to determine the resistance value of the first insulation resistor and the resistance value of the second insulation resistor according to the first group of insulation sampling voltages and the second group of insulation sampling voltages.

[0093] The time constant determination device and insulation detection control device provided in this embodiment belong to the same inventive concept as the time constant determination method provided in any embodiment of the present invention, and have corresponding beneficial effects. For technical details not detailed in this embodiment, please refer to the time constant determination method provided in any embodiment of the present invention.

[0094] Embodiment 5

[0095] Figure 7 It is a structural schematic diagram of an electronic device provided in Embodiment 5 of the present invention. Figure 7 A block diagram of an exemplary electronic device 412 suitable for use in implementing embodiments of the present invention is shown. Figure 7 The electronic device 412 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0096] like Figure 7 As shown, the electronic device 412 is in the form of a general purpose device. The components of the electronic device 412 may include, but are not limited to: one or more processors 416, a storage device 428, and a bus 418 connecting different system components (including the storage device 428 and the processor 416).

[0097] Bus 418 represents one or more of several types of bus structures, including a storage device bus or storage device controller, a peripheral bus, an accelerated graphics port, a processor or a local bus using any of a variety of bus architectures. For example, these architectures include but are not limited to Industry Subversive Alliance (ISA) bus, Micro Channel Architecture (MAC) bus, Enhanced ISA bus, Video Electronics Standards Association (VESA) local bus and Peripheral Component Interconnect (PCI) bus.

[0098] The electronic device 412 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by the electronic device 412, including volatile and non-volatile media, removable and non-removable media.

[0099] The storage device 428 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 430 and / or cache memory 432. The electronic device 412 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, the storage system 434 may be used to read and write non-removable, non-volatile magnetic media ( Figure 7 not shown, usually called a "hard drive"). Although Figure 7 Not shown in the figure, a disk drive for reading and writing a removable non-volatile disk (e.g., a "floppy disk"), and an optical disk drive for reading and writing a removable non-volatile optical disk, such as a read-only optical disk (Compact Disc Read-Only Memory, CD-ROM), a digital video disk (Digital Video Disc-Read Only Memory, DVD-ROM) or other optical media) may be provided. In these cases, each drive may be connected to the bus 418 via one or more data medium interfaces. The storage device 428 may include at least one program product having a set (e.g., at least one) of program modules that are configured to perform the functions of the various embodiments of the present invention.

[0100] A program / utility 440 having a set (at least one) of program modules 442 may be stored, for example, in storage device 428, such program modules 442 including, but not limited to, an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment. Program modules 442 generally perform the functions and / or methods of the embodiments described herein.

[0101] The electronic device 412 may also communicate with one or more external devices 414 (e.g., a keyboard, a pointing terminal, a display 424, etc.), may also communicate with one or more terminals that enable a user to interact with the electronic device 412, and / or communicate with any terminal that enables the electronic device 412 to communicate with one or more other computing terminals (e.g., a network card, a modem, etc.). Such communication may be performed through an input / output (I / O) interface 422. Furthermore, the electronic device 412 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) through a network adapter 420. Figure 7 As shown, the network adapter 420 communicates with other modules of the electronic device 412 via the bus 418. It should be understood that, although not shown in the figure, other hardware and / or software modules can be used in conjunction with the electronic device 412, including but not limited to: microcode, terminal drivers, redundant processors, external disk drive arrays, disk arrays (Redundant Arrays of Independent Disks, RAID) systems, tape drives, and data backup storage systems.

[0102] The processor 416 executes various functional applications and data processing by running the program stored in the storage device 428, for example, implementing the control method for insulation detection provided in the embodiment of the present invention, which includes:

[0103] Receive control instructions;

[0104] According to the control instruction, the first insulating switch is controlled to close, and the insulating voltage when the first insulating switch is closed and the insulating voltage at at least two different preset times after closing are obtained; the insulating voltage is the first capacitor voltage or the second capacitor voltage;

[0105] Determining a first time constant according to an insulation voltage when the first insulation switch is closed and insulation voltages at at least two different preset times after closing;

[0106] Determining a first group of insulation sampling voltages according to a first time constant;

[0107] Controlling the second insulating switch to close, and obtaining the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing;

[0108] determining a second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltage at at least two different preset times after closing;

[0109] Determining a second group of insulation sampling voltages according to a second time constant;

[0110] The resistance value of the first insulation resistor and the resistance value of the second insulation resistor are determined according to the first group of insulation sampling voltages and the second group of insulation sampling voltages.

[0111] Embodiment 6

[0112] Embodiment 6 of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the control method for insulation detection provided in the embodiment of the present invention is implemented. The method includes:

[0113] Receive control instructions;

[0114] According to the control instruction, the first insulating switch is controlled to close, and the insulating voltage when the first insulating switch is closed and the insulating voltage at at least two different preset times after closing are obtained; the insulating voltage is the first capacitor voltage or the second capacitor voltage;

[0115] Determining a first time constant according to an insulation voltage when the first insulation switch is closed and insulation voltages at at least two different preset times after closing;

[0116] Determining a first group of insulation sampling voltages according to a first time constant;

[0117] Controlling the second insulating switch to close, and obtaining the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing;

[0118] determining a second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltage at at least two different preset times after closing;

[0119] Determining a second group of insulation sampling voltages according to a second time constant;

[0120] The resistance value of the first insulation resistor and the resistance value of the second insulation resistor are determined according to the first group of insulation sampling voltages and the second group of insulation sampling voltages.

[0121] The computer storage medium of the embodiment of the present invention can adopt any combination of one or more computer-readable media. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples (non-exhaustive list) of computer-readable storage media include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, a computer-readable storage medium can be any tangible medium containing or storing a program, which can be used by an instruction execution system, device or device or used in combination with it.

[0122] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0123] Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0124] Computer program code for performing the operations of the present invention may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or terminal. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., through the Internet using an Internet service provider).

[0125] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for determining a time constant, characterized in that: The method for determining the time constant is applied to an insulation detection circuit, which includes a first insulation resistor, a second insulation resistor, a first insulation switch, a second insulation switch, a first series resistor, a second series resistor, a first capacitor, and a second capacitor; the first insulation switch is connected in series with the first series resistor and then connected in parallel with the first capacitor, the first capacitor is connected in parallel with the first insulation resistor, the second insulation switch is connected in series with the second series resistor and then connected in parallel with the second capacitor, the second capacitor is connected in parallel with the second insulation resistor, the two ends of the first insulation resistor are connected to the positive electrode of the battery and the ground respectively, and the two ends of the second insulation resistor are connected to the negative electrode of the battery and the ground respectively; the method for determining the time constant includes: Receive control instructions; According to the control instruction, the first insulating switch is controlled to close, and an insulating voltage when the first insulating switch is closed and an insulating voltage at at least two different preset times after closing are obtained; the insulating voltage is the first capacitor voltage or the second capacitor voltage; determining a first time constant according to the insulation voltage when the first insulation switch is closed and the insulation voltages at at least two different preset times after closing; Controlling the second insulating switch to close, and obtaining the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing; The second time constant is determined according to the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing.

2. The method for determining a time constant according to claim 1, characterized in that: The obtaining of the insulation voltage when the first insulating switch is closed and the insulation voltages at at least two different preset times after closing includes: The insulation voltage when the first insulating switch is closed and the insulation voltage when it is closed for t seconds and k1t seconds are obtained, where k1 is a number greater than 1.

3. The method for determining a time constant according to claim 1, characterized in that: The determining of the first time constant according to the insulation voltage when the first insulation switch is closed and the insulation voltages at at least two different preset times after closing includes: According to the insulation voltage U0 when the first insulating switch is closed and the insulation voltage U0 t seconds after closing t And the insulation voltage U when closed k1t seconds k1t , determine U k1t -U0 and U t -U0 ratio, k1 is a number greater than 1; A first time constant τ1 is determined according to the ratio.

4. The method for determining a time constant according to claim 1, characterized in that: The first time constant is τ1, (U k1t -U0) / (U t -U0)=(1-e -k1t / τ1 ) / (1-e -t / τ1 ), where U k1t is the insulation voltage when the first insulating switch is closed for k1t seconds, U0 is the insulation voltage when the first insulating switch is closed, and U t is the insulation voltage when the first insulating switch is closed for t seconds, and k1 is a number greater than 1.

5. The method for determining a time constant according to claim 1, characterized in that: The determining of the second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing includes: According to the insulation voltage U0′ when the second insulating switch is closed and the insulation voltage U0′ t seconds after closing t ' and the insulation voltage U when closed for k2t seconds k2t ′, determine U k2t ′-U0′ and U t ′-U0′ ratio, k2 is a number greater than 1; A second time constant τ2 is determined based on the ratio.

6. The method for determining a time constant according to claim 1, characterized in that: The second time constant is τ2, (U k2t ′-U0′) / (U t ′-U0′)=(1-e -k1t / τ2 ) / (1-e -t / τ2 ), where U k2t ' is the insulation voltage when the second insulating switch is closed for k2t seconds, U0' is the insulation voltage when the second insulating switch is closed, U t ' is the insulation voltage when the second insulating switch is closed for t seconds, and k2 is a number greater than 1.

7. A control method for insulation detection, characterized in that: The control method for insulation detection is applied to an insulation detection circuit, which includes a first insulation resistor, a second insulation resistor, a first insulation switch, a second insulation switch, a first series resistor, a second series resistor, a first capacitor, and a second capacitor; the first insulation switch is connected in series with the first series resistor and then connected in parallel with the first capacitor, the first capacitor is connected in parallel with the first insulation resistor, the second insulation switch is connected in series with the second series resistor and then connected in parallel with the second capacitor, the second capacitor is connected in parallel with the second insulation resistor, the two ends of the first insulation resistor are connected to the positive electrode of the battery and the ground respectively, and the two ends of the second insulation resistor are connected to the negative electrode of the battery and the ground respectively; the control method for insulation detection includes: Receive control instructions; According to the control instruction, the first insulating switch is controlled to close, and an insulating voltage when the first insulating switch is closed and an insulating voltage at at least two different preset times after closing are obtained; the insulating voltage is the first capacitor voltage or the second capacitor voltage; determining a first time constant according to the insulation voltage when the first insulation switch is closed and the insulation voltages at at least two different preset times after closing; Determining a first group of insulation sampling voltages according to the first time constant; Controlling the second insulating switch to close, and obtaining the insulation voltage when the second insulating switch is closed and the insulation voltage at at least two different preset times after closing; determining a second time constant according to the insulation voltage when the second insulation switch is closed and the insulation voltages at at least two different preset times after closing; Determining a second group of insulation sampling voltages according to the second time constant; The resistance value of the first insulation resistor and the resistance value of the second insulation resistor are determined according to the first group of insulation sampling voltages and the second group of insulation sampling voltages.

8. The insulation detection control method according to claim 7, characterized in that: Determining a first group of insulation sampling voltages according to the first time constant includes: When the first insulation switch is closed k3τ1, the voltage of the first insulation resistor and the voltage of the second insulation resistor at this time are determined to be the first group of insulation sampling voltages; τ1 is the first time constant, k3 is a number greater than 0, and the range of k3 is 4.5-5.

5.

9. The control method for insulation detection according to claim 7, characterized in that: The resistance values of the first insulation resistance and the second insulation resistance are calculated by the formulas V1 / (R1 / / R A ) = V2 / R2 and V1′ / R1 = V2′ / (R2 / / R B ), where R A is the resistance value of the first series resistance, R B is the resistance value of the second series resistance, R1 is the resistance value of the first insulation resistance, R2 is the resistance value of the second insulation resistance, V1 is the voltage of the first insulation resistance when the first insulation switch is closed, V2 is the voltage of the second insulation resistance when the first insulation switch is closed, V1′ is the voltage of the first insulation resistance when the second insulation switch is closed, and V2′ is the voltage of the second insulation resistance when the second insulation switch is closed.

10. The insulation detection control method according to claim 7, characterized in that: After the second group of insulation sampling voltages is determined, the method further comprises: The first insulation switch and the second insulation switch are cyclically controlled to be closed at every preset interval, so as to cyclically detect the resistance value of the first insulation resistor and the resistance value of the second insulation resistor.

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