WO2022000206A1 - 一种绝缘电阻检测电路、方法、装置及其存储介质 - Google Patents

一种绝缘电阻检测电路、方法、装置及其存储介质 Download PDF

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Publication number
WO2022000206A1
WO2022000206A1 PCT/CN2020/099031 CN2020099031W WO2022000206A1 WO 2022000206 A1 WO2022000206 A1 WO 2022000206A1 CN 2020099031 W CN2020099031 W CN 2020099031W WO 2022000206 A1 WO2022000206 A1 WO 2022000206A1
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WIPO (PCT)
Prior art keywords
capacitor
voltage
resistor
resistance
value
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PCT/CN2020/099031
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English (en)
French (fr)
Inventor
蒋晶
吴志伟
赵晓鹏
莫维
Original Assignee
华为数字能源技术有限公司
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Application filed by 华为数字能源技术有限公司 filed Critical 华为数字能源技术有限公司
Priority to EP20943354.9A priority Critical patent/EP4155739A4/en
Priority to PCT/CN2020/099031 priority patent/WO2022000206A1/zh
Priority to CN202080056880.8A priority patent/CN114270198A/zh
Publication of WO2022000206A1 publication Critical patent/WO2022000206A1/zh
Priority to US18/069,427 priority patent/US20230128107A1/en

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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/12Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
    • G01R31/14Circuits therefor, e.g. for generating test voltages, sensing circuits
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/52Testing for short-circuits, leakage current or ground faults
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G01R27/025Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H02J7/00304Overcurrent protection
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H02J7/0036Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits using connection detecting circuits
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/005Testing of electric installations on transport means
    • G01R31/006Testing of electric installations on transport means on road vehicles, e.g. automobiles or trucks
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J2310/00The network for supplying or distributing electric power characterised by its spatial reach or by the load
    • H02J2310/40The network being an on-board power network, i.e. within a vehicle
    • H02J2310/48The network being an on-board power network, i.e. within a vehicle for electric vehicles [EV] or hybrid vehicles [HEV]

Definitions

  • the present application relates to the technical field of electric vehicles, and in particular, to an insulation resistance detection circuit, method, device and storage medium thereof.
  • Electric vehicles compared with traditional vehicles, the power supply voltage of the high-voltage power supply system of electric vehicles is often several hundred volts (V).
  • V volts
  • BEVs battery electric vehicles
  • the voltage between the positive pole of the power supply and the negative pole of the power supply is the highest.
  • the two insulation resistances are determined When the resistance of any of the insulation resistances is smaller than the high-voltage power supply system's requirement for the insulation resistance, the power supply in the high-voltage power supply system needs to be disconnected from the load to ensure the safe operation of the high-voltage power supply system.
  • the AC signal injection method refers to injecting an AC signal of a certain frequency between the positive and negative poles of the power supply of the high-voltage power supply system, and by measuring the feedback of the high-voltage power supply system, the resistance value of the insulation resistance of the high-voltage power supply system is obtained.
  • this detection method is applied, the injected AC signal is likely to cause interference to the high-voltage power supply system and affect the normal operation of the system.
  • the external resistance method is to connect a switch and a series of resistances between the positive and negative poles of the power supply of the high-voltage power supply system, and by controlling the on-off of the switch, the voltage value of the insulation resistance of the switch in different states can be obtained, and the voltage value of the insulation resistance voltage can be obtained by listing the voltage of the insulation resistance.
  • Change the equation, the two equations are solved simultaneously to obtain the insulation resistance value of the positive pole to ground and the negative pole to the ground of the power supply in the high-voltage power supply system, and determine the resistance value of the insulation resistance of the positive pole and the negative pole of the power supply to the ground.
  • the switch is opened or closed at a fixed cycle.
  • the insulation resistance between the positive and negative poles of the power supply and the ground fails, the If the insulation resistance is detected at a fixed period, the high-voltage power supply system will not be able to detect the fault of the insulation resistance in time. Therefore, when the insulation resistance fault cannot meet the insulation requirements of the high-voltage power supply system, the above-mentioned detection methods cannot perform fault alarm or processing in time, which affects the safe operation of the high-voltage power supply system, and even causes electric shocks to personnel.
  • the existing insulation resistance detection method cannot detect the failure of the insulation resistance in time, which affects the safe operation of the high-voltage power supply system.
  • the present application provides an insulation resistance detection circuit, method, device and storage medium thereof, which are used to quickly detect whether the insulation resistance is faulty and ensure the safe operation of a high-voltage power supply system.
  • the present application provides an insulation resistance detection circuit, which can be connected to the device to be detected, and is used to detect the insulation resistance between the positive electrode and the negative electrode of the power supply of the device to be detected, and to determine whether the device to be detected is not. Insulation failure occurs.
  • the insulation resistance detection circuit may include: a state control unit, a first voltage dividing branch, a second voltage dividing branch, and a processor.
  • the state control unit is bridged between the positive pole and the negative pole of the power supply of the device to be detected, and the processor is respectively connected with the state control unit, the first voltage dividing branch and the second voltage dividing branch.
  • the state control unit is used for switching between the first state or the second state under the control of the processor.
  • the state control unit When the state control unit is in the first state, the first capacitor is charged and the second capacitor is discharged.
  • the state control unit is in the second state, the first capacitor is discharged and the second capacitor is charged.
  • the first capacitor is the capacitor between the positive electrode of the power supply and the ground.
  • the second capacitor is a capacitor between the negative electrode of the power supply and the ground.
  • the first voltage dividing branch is used to be connected in parallel with the first capacitor, and used to divide the voltage across the first capacitor to obtain a first voltage waveform.
  • the second voltage dividing branch is used to be connected in parallel with the second capacitor, and used to divide the voltage across the second capacitor to obtain a second voltage waveform.
  • the processor is used to: calculate the characteristic value of the first capacitor voltage at different times within the set time period before the current time according to the first voltage waveform obtained at the current time; and calculate the voltage before the current time according to the second voltage waveform obtained at the current time.
  • the second capacitor voltage characteristic value at different times within the set duration of the When the next switching time is reached, the state control unit is controlled to perform state switching.
  • control state control unit switches between the first state and the second state, so as to control the first capacitor and the second capacitor to charge and discharge.
  • the control state control unit switches between the first state and the second state, so as to control the first capacitor and the second capacitor to charge and discharge.
  • the change law changes, so it is possible to detect whether the insulation resistance changes in time by calculating the characteristic value of the first capacitor voltage at different times and/or the characteristic value of the second capacitor voltage at different times, and when it is determined that the insulation resistance changes, the change Switch the time, so as to obtain the waveform corresponding to the insulation resistance at the current time as soon as possible to calculate the resistance value of the insulation resistance, so that when the resistance value of the insulation resistance is not up to the requirements, the device to be detected can be quickly protected.
  • the processor is further configured to: determine the first voltage waveform according to the obtained first voltage waveform and the obtained second voltage waveform in the first state and the second state after reaching the next switching moment
  • the resistance value of the resistance and the resistance value of the second resistance is used to determine whether an insulation resistance fault has occurred.
  • the first voltage resistance value and the second resistance value can be calculated according to the first voltage waveform and the second voltage waveform corresponding to the current insulation resistance at the next switching moment when the state switching unit is in the first state and the second state
  • the resistance value of the first resistor and the resistance value of the second resistor are used to accurately determine whether the device to be tested has insulation failure.
  • the first switch unit may include: the state control unit includes: a first switch unit and a second switch unit.
  • the first end of the first switch unit is connected to the positive pole of the power supply, and the second end of the first switch unit is connected to the ground.
  • the second end of the second switch unit is connected to the negative pole of the power supply, and the second end of the second switch unit is connected to the ground.
  • the charging or discharging of the first capacitor and the second capacitor can be controlled respectively by controlling the working states of the first switch unit and the second switch unit, so as to realize precise control of the state of the control unit in the first state and the second state. switch between.
  • the first switch unit includes: a first switch and a third resistor.
  • the first end of the third resistor is connected to the positive pole of the power supply, and the second end of the third resistor is connected to the first end of the first switch.
  • the second end of the first switch is connected to the ground, and the control end of the first switch is connected to the processor.
  • the charging and discharging timing of the first capacitor can be controlled by controlling the working state of the first switch, and the third resistor is used to limit the current, thereby preventing the first switch from short-circuiting the positive electrode of the power supply to the ground.
  • the second switch unit includes: a second switch and a fourth resistor.
  • the first end of the second switch is connected to the ground, the second end of the second switch is connected to the first end of the fourth resistor, and the control end of the second switch is connected to the processor.
  • the second end of the fourth resistor is connected to the negative pole of the power supply.
  • the charging and discharging timing of the second capacitor can be controlled by controlling the working state of the second switch, and the fourth resistor is used to limit the current, thereby preventing the second switch from short-circuiting the negative electrode of the power supply to the ground.
  • the first voltage dividing branch may include: a fifth resistor and a sixth resistor.
  • one end of the fifth resistor is connected to the positive pole of the power supply, and the second end of the fifth resistor is respectively connected to the first end of the sixth resistor and the processor.
  • the second end of the sixth resistor is connected to the ground and the processor.
  • the second voltage dividing branch may include: a seventh resistor and an eighth resistor.
  • the first end of the seventh resistor is connected to the ground and the processor, and the second end of the seventh resistor is respectively connected to the first end of the eighth resistor and the processor.
  • the second end of the eighth resistor is connected to the negative pole of the power supply.
  • the insulation resistance detection circuit provided by the embodiment of the present application further includes: a ninth resistor and a third switch.
  • the first end of the ninth resistor is respectively connected with the positive pole of the power supply and the processor
  • the second end of the ninth resistor is respectively connected with the first end of the third switch and the processor
  • the resistance value of the ninth resistor is less than the preset threshold .
  • the second end of the third switch is connected to the ground
  • the control end of the third switch is connected to the processor.
  • the processor is further configured to: control the closing and opening of the third switch; according to the first voltage waveform obtained by the first voltage dividing branch and the second voltage dividing branch within a period of time after reaching the next switching time
  • the obtained second voltage waveform and the voltage waveform across the ninth resistor when the third switch is closed are used to calculate the parallel resistance value of the first resistor and the second resistor, and the parallel resistance value is used to determine whether an insulation resistance fault occurs.
  • the first resistor and the second resistor are connected in series between the positive electrode and the negative electrode of the power supply of the device to be detected, when any one of the first resistor and the second resistor fails, it will affect the device to be detected. Therefore, by detecting the parallel resistance of the first resistance and the second resistance, it can be determined whether the insulation failure of the device to be detected has occurred. Since it is not necessary to calculate the resistance value of the first resistor and the resistance value of the second resistor, the calculation amount of the processor is reduced.
  • an embodiment of the present application provides a monitoring device for a high-voltage system, and the high-voltage system monitoring device can be connected to the high-voltage system for monitoring the working state of the high-voltage system.
  • the monitoring device may include: a switch module, an alarm module, a communication module, and the insulation resistance detection circuit provided by the first aspect of the embodiments of the present application.
  • the insulation resistance detection circuit is connected with the communication module, and the communication module is connected with the alarm module.
  • the switch module is used to connect between the power supply and the load of the high-voltage system.
  • the insulation resistance detection circuit is used to detect the resistance of the first resistance between the positive pole of the power supply and the ground and the resistance of the second resistance between the negative pole of the power supply and the ground, and compare the resistance of the first resistance with the resistance of the second resistance.
  • the resistance value is sent to the communication module.
  • the communication module is used to notify the alarm module to give an alarm when it is determined that the resistance value of the first resistor or the resistance value of the second resistor is less than the first preset resistance threshold; and when the resistance value of the first resistor or the resistance value of the second resistor is less than When the second preset resistance threshold is reached, the control switch module is turned off.
  • an embodiment of the present application provides an insulation resistance detection method
  • the execution body of the method may be the processor in the insulation resistance circuit provided in the first aspect of this embodiment or another processor communicatively connected to the device to be detected.
  • the method specifically includes the following steps: obtaining a first voltage waveform corresponding to a first capacitor and a second voltage waveform corresponding to a second capacitor, where the first capacitor is the capacitor between the positive electrode of the power supply of the device to be detected and the ground, and the second capacitor is Capacitance between the negative pole of the power supply and the ground; control the first capacitor and the second capacitor to switch between the first state or the second state, the first state is that the first capacitor is charged and the second capacitor is discharged, and the second state is the first state The capacitor is discharged and the second capacitor is charged; according to the first voltage waveform obtained at the current moment, calculate the characteristic value of the voltage of the first capacitor at different times within the set time period before the current moment; and according to the second voltage waveform obtained at the current moment , calculate the
  • the characteristic value of the first capacitor voltage at different times and the characteristic value of the second capacitor voltage at different times can be used to determine whether the resistance value of the insulation resistance of the device to be detected has changed, and whether the state of the first capacitor and the second capacitor has changed. Adjust the switching time. Since the first voltage waveform and the second voltage waveform corresponding to the insulation resistance need to be obtained when calculating the resistance value of the insulation resistance of the device to be detected, the above method can be used to obtain the resistance value as soon as possible when the resistance value of the insulation resistance changes.
  • the voltage waveform corresponding to the resistance value of the insulation resistance ensures that when the resistance value of the insulation resistance changes, it can be detected as soon as possible whether the resistance value of the current insulation resistance meets the insulation requirements of the device to be tested, so as to determine whether the device to be tested has insulation failure. .
  • the method further includes:
  • first voltage waveform and second voltage waveform determine the resistance value of the first resistor and the resistance value of the second resistor.
  • the first resistor is the insulation resistance between the positive pole of the power supply and the ground
  • the second resistance is the The insulation resistance between the negative pole and the ground, the resistance of the first resistance and the resistance of the second resistance are used to determine whether an insulation resistance fault occurs.
  • the first voltage waveform and the second voltage waveform corresponding to the resistance value of the first resistor and the resistance value of the second resistor at the current moment are obtained, and the The voltage waveform can accurately calculate the resistance value of the first resistor and the resistance value of the second resistor.
  • determining the next switching moment of the first capacitor and the second capacitor according to the characteristic value of the voltage of the first capacitor at different times and/or the characteristic value of the voltage of the second capacitor at different times including:
  • the first voltage waveform and The second voltage waveform changes with a fixed law, and two adjacent eigenvalues in the calculated first capacitor voltage eigenvalues at different times are equal or similar, and/or two adjacent eigenvalues in the second capacitor voltage eigenvalues at different times
  • the values are equal or similar; when the difference between the two adjacent voltage characteristic values of the first capacitor voltage characteristic values at different times is greater than the preset error threshold, and/or the adjacent second capacitor voltage characteristic values at different times.
  • the difference between the two voltage characteristic values is greater than the preset error threshold, it can be determined that the resistance value of the first resistor and/or the resistance value of the second resistor changes at the current moment, and the state of the first capacitor and the second capacitor is immediately changed.
  • the switching is performed to obtain the voltage waveform corresponding to the change of the resistance value of the first resistor
  • the resistance values of the first resistor and the second resistor are determined according to the continuously obtained first voltage waveform and the second voltage waveform, including:
  • the insulation resistance detection method provided by the embodiment of the present application further includes:
  • a shutdown command is sent to the device to be detected, and the shutdown command is used to instruct the device to be detected to disconnect the power supply from the load.
  • the insulation resistance detection method provided by the embodiment of the present application further includes:
  • a shutdown instruction is sent to the device to be detected, and the shutdown instruction is used to instruct the device to be detected to disconnect the power supply from the load.
  • the first resistor is connected in parallel with the first capacitor
  • the second resistor is connected in parallel with the second capacitor, and is connected in series between the positive electrode and the negative electrode of the power supply of the device to be detected.
  • the voltage and the voltage between the negative electrode and the ground are relatively high.
  • the first capacitor voltage characteristic value includes one or more of the following: the time constant of the first capacitor and the voltage waveform state of the first capacitor;
  • the second capacitor voltage characteristic value includes one or more of the following: the first capacitor The time constant of the second capacitor and the voltage waveform state of the second capacitor; the waveform state of the first capacitor represents the fluctuation trend of the voltage across the first capacitor, and the waveform state of the second capacitor represents the waveform trend of the voltage across the second capacitor.
  • an embodiment of the present application provides an insulation resistance detection device.
  • the insulation resistance detection device includes an acquisition module, a processing unit, and a calculation module.
  • the acquiring unit may be used to acquire a first voltage waveform corresponding to the first capacitor and a second voltage waveform corresponding to the second capacitor, where the first capacitor is the capacitor between the positive pole of the power supply to be detected and the ground, and the second capacitor is the Capacitance between negative and ground.
  • the processing unit can be used to control the first capacitor and the second capacitor to switch between a first state or a second state, the first state is that the first capacitor is charged and the second capacitor is discharged, and the second state is that the first capacitor is discharged and the second state is Capacitor charging.
  • the calculation unit is used to calculate the characteristic value of the first capacitor voltage at different times within the set time period before the current moment according to the first voltage waveform obtained at the current moment; and according to the second voltage waveform obtained at the current moment, calculate the The characteristic value of the second capacitor voltage at different times within the set time period before the current time.
  • the processing unit is further configured to determine the next switching moment according to the first capacitor voltage characteristic value at different times and/or the second capacitor voltage characteristic value at different times output by the computing unit; and control the first capacitor when the next switching moment is reached State switching with the second capacitor.
  • the acquisition unit is further configured to: continue to acquire the first voltage waveform and the second voltage waveform after controlling the first capacitor and the second capacitor to perform state switching when the next switching moment is reached; the processing unit also uses In: determining the resistance value of the first resistor and the resistance value of the second resistor according to the first voltage waveform and the second voltage waveform continuously obtained by the obtaining unit.
  • the first resistance is the insulation resistance between the positive pole of the power supply and the ground
  • the second resistance is the insulation resistance between the negative pole of the power supply and the ground
  • the resistance of the first resistance and the resistance of the second resistance are used to determine whether the occurrence of Insulation resistance failure.
  • the processing unit is specifically configured to: compare any two adjacent voltage characteristic values of the first capacitor voltage characteristic values at different times, and/or compare the second capacitor voltage characteristic values at different times Comparing any two adjacent voltage characteristic values; when determining that the difference between any two adjacent voltage characteristic values is greater than the preset error threshold, determine the current moment as the next switching moment; and when determining any two adjacent voltage characteristics When the value is less than or equal to the preset error threshold, determine the time constant of the first capacitor and/or the time constant of the second capacitor, and determine the next switching moment according to the time constant of the first capacitor and/or the time constant of the second capacitor .
  • the processing unit is specifically configured to: when it is determined that any two adjacent voltage characteristic values are less than or equal to a preset error threshold, record the first voltage of the first capacitor and the second capacitor at each switching moment The first voltage value and the second voltage value corresponding to the waveform and the second voltage waveform; and when it is determined that the difference between any two adjacent voltage characteristic values is greater than the preset error threshold, delete the first voltage value and the first voltage value recorded before the current moment.
  • the processing unit is further configured to: when it is determined that the resistance value of the first resistor or the resistance value of the second resistor is smaller than the first preset insulation threshold, send a shutdown instruction to the device to be detected, and the shutdown instruction uses It is used to instruct the device to be tested to disconnect the power supply from the load.
  • the processing unit is further configured to: determine the parallel resistance value of the first resistor and the second resistor according to the continuously acquired first voltage waveform and the second voltage waveform, and determine the resistance value of the first resistor and the second resistor in parallel. Parallel resistance; when it is determined that the parallel resistance is less than the second preset insulation threshold, a shutdown command is sent to the device to be detected, and the shutdown command is used to instruct the device to be detected to disconnect the power supply from the load.
  • the first capacitor voltage characteristic value includes one or more of the following: the time constant of the first capacitor and the voltage waveform state of the first capacitor;
  • the second capacitor voltage characteristic value includes one or more of the following: the first capacitor The time constant of the second capacitor and the voltage waveform state of the second capacitor; the waveform state of the first capacitor represents the fluctuation trend of the voltage across the first capacitor, and the waveform state of the second capacitor represents the waveform trend of the voltage across the second capacitor.
  • the embodiments of the present application further provide a computer-readable storage medium, where computer-readable instructions are stored in the computer-readable storage medium, and when the computer-readable instructions are run on a computer, the third aspect or the The method in any of the three possible designs is performed.
  • Fig. 1 is the structural schematic diagram of the application scene of the insulation resistance detection device of the present application
  • FIG. 2 is a schematic structural diagram of an insulation resistance detection circuit in an embodiment of the application.
  • FIG. 3 is a schematic diagram 1 of a circuit structure of a state control unit in an embodiment of the present application.
  • FIG. 4 is a schematic diagram 1 of the circuit structure of an insulation resistance detection circuit according to an embodiment of the application.
  • FIG. 5 is a schematic diagram 1 of a first voltage and a second voltage variation curve in an embodiment of the present application
  • FIG. 6 is a schematic diagram 2 of a first voltage and a second voltage change curve in an embodiment of the application
  • FIG. 7 is a schematic diagram 3 of a first voltage and a second voltage change curve in an embodiment of the present application.
  • FIG. 8 is a second schematic diagram of the circuit structure of an insulation resistance detection circuit according to an embodiment of the application.
  • FIG. 9 is a schematic structural diagram of a high-voltage system monitoring device in an embodiment of the application.
  • FIG. 10 is a schematic flowchart of an insulation resistance detection method in an embodiment of the present application.
  • FIG. 11 is a schematic flowchart of an insulation resistance detection method in an embodiment of the present application.
  • FIG. 12 is a schematic structural diagram of an insulation resistance detection device in an embodiment of the present application.
  • Embodiments of the present application provide an insulation resistance detection circuit, method, device, and storage medium thereof.
  • the methods and devices are conceived based on the same or similar technologies. Since the principles of the methods and devices for solving problems are similar, the implementation of the devices and the methods can be referred to each other, and repeated descriptions will not be repeated here.
  • the insulation resistance-based detection circuit, method, device and storage medium thereof provided by the embodiments of the present application can be applied to electric vehicles, numerically controlled machine tools, wind power generation systems, photovoltaic power generation systems, and other devices using high-voltage power supply, for detecting the device to be detected Check whether the insulation resistance between the positive and negative poles of the power supply fails.
  • FIG. 1 exemplarily shows an application scenario of an electric vehicle.
  • an electric vehicle at least includes: a power module, a high-voltage power-on and off-load module, and a high-voltage load.
  • the power module includes multiple battery packs for supplying power to the high-voltage load, and the high-voltage power-on/off module is used to control the connection between the power module and the high-voltage load.
  • the insulation resistance detection circuit provided by the embodiment of the present application can be connected between the positive output terminal HVDC+ and the negative output terminal HVDC- of the power supply of the power module to detect whether the insulation resistance between the positive and negative terminals of the power module fails.
  • the insulation resistance detection circuit 200 can be connected to the positive pole of the power supply of the device to be detected and the negative pole of the power supply, and is used to quickly and accurately detect the power supply to be detected.
  • the insulation resistance detection circuit 200 may include: a state control unit 201 , a first voltage dividing branch 202 , a second voltage dividing branch 203 and a processor 204 .
  • the state control unit 201 is connected across the positive pole HVDC+ of the power supply of the device to be detected and the negative pole HVDC- of the power supply.
  • the processor 204 is respectively connected to the state control unit 201 , the first voltage dividing branch 202 and the second voltage dividing branch 203 .
  • the state control unit 201 switches between the first state or the second state under the control of the processor 204 .
  • the state control unit 204 When the state control unit 204 is in the first state, the first capacitor C1 is charged and the second capacitor is discharged C2; when the state control unit 201 is in the second state, the first capacitor C1 is discharged and the second capacitor C2 is charged, and the first capacitor C1 is the positive pole of the power supply
  • the capacitance between the ground and the second capacitor C2 is the capacitance between the negative pole of the power supply and the ground.
  • the first voltage dividing branch 202 is used for connecting in parallel with the first capacitor C1 and for dividing the voltage across the first capacitor C1 to obtain a first voltage waveform.
  • the second voltage dividing branch 203 is used for connecting in parallel with the second capacitor C2 and dividing the voltage across the second capacitor C2 to obtain a second voltage waveform.
  • the processor 204 is used for: calculating the characteristic value of the first capacitor voltage at different times within the set time period before the current time according to the first voltage waveform obtained at the current time; and calculating the current value according to the second voltage waveform obtained at the current time.
  • the characteristic value of the second capacitor voltage at different times within the set time period before the time; and according to the characteristic value of the first capacitor voltage at different times and/or the characteristic value of the second capacitor voltage at different times, the next switching time is determined, and when it arrives At the next switching time, the state control unit 201 is controlled to perform state switching.
  • the processor 204 controls the state control unit 201 to perform state switching when the next switching time is reached, and uses the subsequent state control unit 201 to be in the first state and the second state
  • the first voltage dividing branch 202 has obtained
  • the first voltage waveform obtained by the second voltage dividing branch 203 and the second voltage waveform obtained by the second voltage dividing branch 203 determine the resistance value of the first resistor R1 and the resistance value of the second resistor R2.
  • the first resistance R1 is the insulation resistance between the positive pole of the power supply and the ground
  • the second resistance R2 is the insulation resistance between the negative pole of the power supply and the ground
  • the resistance value of the first resistance R1 and the resistance value of the second resistance R2 are determined by It is used to determine whether insulation resistance failure occurs in the device to be tested, and whether there is an insulation failure.
  • the first capacitor C1 is connected in parallel with the first voltage dividing branch 202 . Therefore, the voltage variation across the first capacitor C1 can be determined by detecting the first voltage waveform on the first voltage dividing branch 202 . Similarly, the voltage variation across the second capacitor C2 can be determined by detecting the second voltage waveform of the second voltage dividing branch 203 .
  • the state control unit 201 controls the charging process and discharging process of the first capacitor C1 and the second capacitor C2. If the resistance value of the first resistor R1 and the resistance value of the second resistor R2 remain unchanged, the obtained first The voltage waveform and the obtained second voltage waveform change with a fixed rule, and the first capacitor voltage characteristic values obtained at different times and/or the second capacitor voltage characteristic values obtained at different times are equal or similar. If during the charging process and discharging process of the first capacitor and the second capacitor, if the resistance value of the first resistor R1 and the resistance value of the second resistor R2 change, the resistance value of the first resistor R1 and the resistance value of the second resistor R2 will change.
  • the voltage characteristic value of the changed second capacitor determines whether the current resistance value of the first resistor R1 and the resistance value of the second resistor R2 have changed, and according to the change of the resistance value of the first resistor R1 and the resistance value of the second resistor R2 Adjust the state switching time of the state control unit 201 to obtain the first voltage waveform and the second voltage waveform corresponding to the current resistance value of the first resistor R1 and the resistance value of the second resistor R2 as soon as possible, so as to accurately calculate the value of the first resistor R1.
  • first capacitor C1 and the second capacitor C2 are connected in series between the positive electrode HVDC+ negative electrode HVDC- of the power supply, when the first resistor R1 connected in parallel with the first capacitor C1 changes, the voltage across the first capacitor C1 changes, and the voltage value between the positive HVDC+ negative HVDC- of the power supply remains unchanged, so the voltage across the second capacitor C2 will also change accordingly. Therefore, it is possible to detect the voltage characteristic value of the first capacitor C1 at different times or different The voltage characteristic value of the second capacitor C2 at the moment can determine whether the resistance value of the first resistor R1 and the resistance value of the second resistor R2 change.
  • the voltage characteristic values of the first capacitor C1 at different times can be simultaneously detected by detecting and the voltage characteristic value of the second capacitor C2 at different times to accurately determine whether the resistance value of the first resistor R1 and the resistance value of the second resistor R2 change, so as to accurately determine the next switching time.
  • the voltage characteristic value of the first capacitor C1 may be, but not limited to, the time constant of the first capacitor and/or the voltage waveform state of the first capacitor.
  • the second capacitor voltage characteristic value may be, but not limited to, the time constant of the second capacitor and/or the voltage waveform state of the second capacitor.
  • the waveform state of the first capacitor represents the fluctuation trend of the voltage across the first capacitor
  • the waveform state of the second capacitor represents the waveform trend of the two ends of the second capacitor.
  • the direction of the first voltage waveform and the direction of the second voltage waveform are the same, wherein the direction of the first voltage waveform and the second voltage waveform are the same, and the specific meaning may be: the first voltage dividing branch 202 outputs the first voltage In the waveform, one end that outputs a high potential is connected to one end of the processor 204 that receives a high potential, and the first end that outputs a low potential is connected to one end of the processor 204 that receives a low potential, and the difference between the high and low potentials is equal to the first voltage; the second voltage divider When the branch 203 outputs the second voltage waveform, the end of the output high potential is connected to the end of the processor 204 that receives the high potential, the end of the output low potential is connected to the end of the processor 204 that receives the low potential, and the difference between the high and low potentials is the second voltage. .
  • the state control unit 201 can be switched between the first state and the second state through the processor 204 .
  • the processor 204 may send a control signal to the state control unit 201 to control the state control unit 201 to be in the first state or the second state.
  • the first state may be, but not limited to, the first capacitor C1 is charged and the second capacitor C2 is discharged.
  • the second state may be, but is not limited to: the first capacitor C1 is discharged and the second capacitor C2 is charged.
  • the device to be detected may be provided with a fixed interface, and the insulation resistance detection circuit 200 may be connected to the device to be detected through the fixed interface, so as to detect the resistance value of the first resistor R1 and the resistance value of the second resistor R2.
  • the processor 204 can be connected to the state control unit 201 and send a control signal to the state control unit 201. After the state control unit 201 receives the control signal, it controls the state control unit 201 to be in the first state in response to the control signal. and the second state.
  • the processor 204 may be any one of a microcontroller unit (microcontroller unit, MCU), a central processing unit (central processing unit, CPU), and a digital signal processor (digital signal processor, DSP).
  • MCU microcontroller unit
  • CPU central processing unit
  • DSP digital signal processor
  • the specific form of the processor is not limited to the above examples.
  • the state control unit 201 is connected between the positive pole and the negative pole of the power supply of the device to be detected, and the state control unit 201 can be used to switch between the first state or the second state under the control of the processor 204 .
  • the state control unit 201 when the state control unit 201 is in the first state, the first capacitor C1 is charged and the second capacitor C2 is discharged; when the state control unit 201 is in the second state, the first capacitor C1 is discharged and the second capacitor C2 is charged, and the first capacitor C1 is the power source
  • the capacitance between the positive pole of the power supply and the ground, and the second capacitance C2 is the capacitance between the negative pole of the power supply and the ground.
  • the state control unit 201 may include a first switch unit and a second switch unit.
  • the first end of the first switch unit is connected to the positive pole of the power supply, and the second end of the first switch unit is connected to the ground.
  • the second end of the second switch unit is connected to the negative pole of the power supply, and the second end of the second switch unit is connected to the ground.
  • the state control unit 201 is in the first state when the first switch unit is closed and the second switch unit is disconnected. When the first switch unit is turned off and the second switch unit is turned on, the state control unit 201 is in the second state.
  • the function of setting the first switch unit is to control the discharge and charging of the first capacitor connected in parallel with the first switch unit through the closing and opening of the first switch unit
  • the function of setting the second switch unit is to: pass the second switch unit The closing and opening of control the discharge and charge of the second capacitor connected in parallel with the second switch unit.
  • the first switch unit may include a first switch and a third resistor.
  • the second switch unit may include a second switch and a fourth resistor.
  • the function of setting the first switch is to control the charging or discharging of the first capacitor by changing the state of the first switch.
  • the functions of setting the third resistor are: to provide a discharge path for the first capacitor and to avoid a short circuit between the positive pole of the power supply and the ground when the first switch is closed.
  • the function of setting the second switch is to control the charging or discharging of the second capacitor by changing the state of the second switch.
  • the function of setting the fourth resistor is to provide a discharge path for the second capacitor to avoid a short circuit between the negative pole of the power supply and the ground when the second switch is closed.
  • the first end of the third resistor is connected to the positive pole of the power supply
  • the second end of the third resistor is connected to the first end of the first switch
  • the second end of the first switch is connected to the ground
  • the first end of the second switch is connected to the ground
  • the end is connected to the ground
  • the second end of the second switch is connected to the first end of the fourth resistor
  • the second end of the fourth resistor is connected to the negative electrode of the power supply.
  • the first switch and the second switch may be switch transistors. If the first switch and the second switch are metal oxide semiconductor (metal oxide semiconductor, MOS) transistors, the gates of the MOS transistors may be the first switch and the second switch.
  • the control terminal of the switch unit is connected to the processor 204, and the processor 204 realizes the switching of the control state control unit 201 between the first state and the second state by controlling the on-off of the MOS transistor; if the first switch and the second switch are bipolar A junction transistor (bipolar junction transistor, BJT), the base of the BJT can be the control terminal of the first switch and the second switch connected to the processor 204, and the processor 204 can control the on-off of the BJT to realize the control state control unit 201. switch between the first state and the second state.
  • BJT bipolar A junction transistor
  • FIG. 3 it is a schematic structural diagram of the state control unit 201 in the embodiment of the present application.
  • switches K1 and K2, resistors R3 and R4 are included.
  • a and B as the input terminals of the state switching unit 201, are respectively connected to the positive HVDC+ and negative HVDC- of the power supply of the device to be detected
  • C and D are used as the control terminals of the state control unit 201, and both are connected to the processor 204
  • E and F as the output terminals of the state control unit 201, are respectively connected to the first voltage dividing branch 202 and the second voltage dividing branch 203.
  • the connection relationship of each device may be: the first end of R3 is connected to the positive HVDC+ power supply of the device to be detected, the second end of R3 is connected to the first end of K1, and the control of K1
  • the terminal is connected to the processor 204, the second terminal of K1 is connected to the second terminal of K2 and the ground wire respectively, the control terminal of K2 is connected to the processor 204, the second terminal of K2 is connected to the first terminal of R4, and the first terminal of R4 is connected to the first terminal of R4.
  • the two terminals are connected to the negative HVDC- of the power supply of the device to be detected.
  • the state control unit 201 shown in FIG. 3 is used to control the charging and discharging of the first capacitor C1 and the second capacitor C2, taking the first capacitor C1 as an example, when K1 is disconnected, the resistances across C1 are the first resistor R1 and the second capacitor C1.
  • a resistor on the voltage dividing branch 202, HVDC+ charges the first capacitor C1 through the first resistor R1 and the first voltage dividing branch 202, until the voltage across the first capacitor C1 is charged to a steady state value, when K1 is closed,
  • the first capacitor C1 provides current for R3, and at this time, the first capacitor C1 is discharged through R3, the first voltage dividing branch, and the first resistor R1.
  • the charging or discharging of the second capacitor C2 can be controlled by controlling the switch K2.
  • the state control unit 201 may also adopt other structures.
  • the state control unit 201 may use a relay, and by changing the input quantity of the relay, the state control unit 201 can be first state and second state.
  • the first voltage dividing branch 202 is used for connecting in parallel with the first capacitor C1, and the first voltage dividing branch 202 can be used for dividing the voltage across the first capacitor C1 to obtain a first voltage waveform.
  • the insulation detection circuit 200 provided in the embodiment of the present application is connected to the positive pole and the negative pole of the power supply of the device to be detected, and the voltage between the positive pole and the negative pole of the power supply is relatively high, therefore, the directly obtained voltage at both ends of the first capacitor C1 The voltage may be difficult to meet the voltage requirements of the processor 204. Therefore, by obtaining the voltage on the first voltage dividing branch 202 connected in parallel with the first capacitor C1, the output of the first capacitor C1 that meets the voltage requirements of the processor 204 can be realized. The first voltage waveform of the terminal voltage change.
  • the first voltage dividing branch 202 may include: a fifth resistor and a sixth resistor.
  • One end of the fifth resistor is connected to the positive pole of the power supply, the second end of the fifth resistor is connected to the first end of the sixth resistor and the processor 204 respectively; the second end of the sixth resistor is connected to the ground and the processor 204 .
  • the resistance value of the sixth resistor is far smaller than the resistance value of the fifth resistor.
  • the functions of setting the fifth resistor and the sixth resistor are: since the first voltage dividing branch 202 is connected in parallel with the first capacitor C1, the voltage across the first capacitor C1 can be divided by the fifth resistor and the sixth resistor. voltage, and by detecting the voltage waveform across the sixth resistor, the voltage waveforms of the first capacitor C1 during charging and discharging are obtained, so that the voltage across the first capacitor C1 can be obtained without using a high-voltage detection device with higher detection cost.
  • the resistance value of the sixth resistor is much smaller than the resistance value of the fifth resistor.
  • the resistance values of the fifth resistor and the sixth resistor may be set according to the application scenario of the insulation resistance detection circuit 200 and the specifications of the processor 204, which are not described in detail here in this application.
  • the above description of the structure of the first voltage dividing branch 202 is only an example. In practical applications, the first voltage dividing branch 202 may also adopt other structures. For example, the first voltage dividing branch 202 may be set to adopt two or more structures. A structure in which resistors are connected in series.
  • the second voltage dividing branch 203 is configured to be connected in parallel with the second capacitor C2, and the second voltage dividing branch 203 may be used to divide the voltage across the second capacitor C2 to obtain a second voltage waveform.
  • the insulation detection circuit 200 provided in the embodiment of the present application is connected to the positive pole and the negative pole of the power supply of the device to be detected, and the voltage between the positive pole and the negative pole of the power supply is relatively high, therefore, the directly obtained voltage at both ends of the second capacitor C2 The voltage may be difficult to meet the voltage requirements of the processor 204. Therefore, by obtaining the voltage on the second voltage dividing branch 203 connected in parallel with the second capacitor C2, the output of the second capacitor C2 that meets the voltage requirements of the processor 204 can be realized. The second voltage waveform of the terminal voltage change.
  • the second voltage dividing branch 203 may include: a seventh resistor and an eighth resistor.
  • the first end of the seventh resistor is connected to the ground and the processor 204, the second end of the seventh resistor is respectively connected to the first end of the eighth resistor and the processor 204; the second end of the eighth resistor is connected to the negative electrode of the power supply connect.
  • the resistance value of the seventh resistor is far smaller than the resistance value of the fifth resistor.
  • the functions of setting the seventh resistor and the eighth resistor are: since the second voltage dividing branch 203 is connected in parallel with the first capacitor, the voltage across the second capacitor C2 can be divided by the seventh resistor and the eighth resistor. , and by detecting the voltage waveform across the seventh resistor, the voltage waveforms of the second capacitor C2 during charging and discharging are obtained, so that the voltage across the second capacitor C2 can be obtained without using a high-voltage detection device with higher detection cost.
  • the resistance value of the seventh resistor is much smaller than the resistance value of the eighth resistor.
  • the resistance values of the seventh resistor and the eighth resistor can be set according to the application scenario of the insulation resistance detection circuit 200 and the specifications of the processor 204, which are not described in detail here in this application.
  • the above description of the structure of the second voltage dividing branch 203 is only an example.
  • the second voltage dividing branch 203 may also adopt other structures.
  • the second voltage dividing branch 203 may be set to adopt more than two A structure in which resistors are connected in series.
  • the processor 204 is respectively connected with the state control unit 201, the first voltage dividing branch 202 and the second voltage dividing branch 203, and the processor 204 can be used to calculate the setting before the current time according to the first voltage waveform obtained at the current time The characteristic value of the first capacitor voltage at different times in the duration; and according to the second voltage waveform obtained at the current moment, calculate the characteristic value of the second capacitor voltage at different times in the set duration before the current moment; The capacitor voltage characteristic value and/or the second capacitor voltage characteristic value at different times determines the next switching time of the state control unit 201, and controls the state control unit 201 to perform state switching when the next switching time is reached.
  • the processor 204 can also be used to control the state control unit 201 to perform state switching when the next switching moment is reached, and determine the first resistance R1 from the first voltage waveform and the second voltage waveform obtained in the first state and the second state. and the resistance of the second resistor R2.
  • the first resistance R1 is the insulation resistance between the positive pole of the power supply and the ground
  • the second resistance R2 is the insulation resistance between the negative pole of the power supply and the ground
  • the resistance of the first resistance R1 and the resistance of the second resistance R2 are determined by It is used to determine whether the insulation resistance fault occurs in the device to be tested.
  • the first capacitor voltage characteristic value may be, but not limited to, the time constant of the first capacitor and/or the voltage waveform state of the first capacitor.
  • the second capacitor voltage characteristic value may be, but not limited to, the time constant of the second capacitor and/or the voltage waveform state of the second capacitor.
  • the waveform state of the first capacitor represents the fluctuation trend of the voltage across the first capacitor
  • the waveform state of the second capacitor represents the waveform trend of the voltage across the second capacitor.
  • the characteristic value of the first capacitor voltage is in a voltage waveform state, when between any two adjacent voltage values in the first voltage waveform, when the second value after the second value is greater than the preset threshold value of the first value before, it can be It is determined that the waveform trend of the voltage across the first capacitor at the time corresponding to the second value is rising, and the characteristic value of the voltage of the first capacitor at the time corresponding to the second value can be determined to be 1. If the latter second value is smaller than the former first value, it can be determined that the waveform trend of the voltage across the first capacitor at the moment corresponding to the second value is decreasing, and the characteristic value of the voltage of the first capacitor at the moment corresponding to the second value can be determined 0.
  • the preset threshold may be set according to the application scenario of the insulation resistance detection circuit 200, which is not described in detail here in this application.
  • any two adjacent voltage characteristic values of the first capacitor voltage characteristic values at different times are compared, and/or the difference between any two adjacent voltage characteristic values of the second capacitor voltage characteristic values at different times is compared.
  • the difference is greater than the preset error threshold
  • the first voltage waveform and the second voltage waveform can accurately detect whether the device to be tested currently has an insulation fault.
  • the difference between any two adjacent voltage characteristic values of the first capacitor voltage characteristic values at different times is less than or equal to the preset error threshold, and/or the difference between any adjacent two voltage characteristic values of the second capacitor voltage characteristic values at different times is When the difference between the voltage characteristic values is less than or equal to the preset error threshold, it can be determined that the resistance value of the first resistor R1 and the resistance value of the second resistor R2 remain unchanged at this moment, and the time constant of the first capacitor and the time of the second capacitor can be determined.
  • the preset error threshold may be set to 1.
  • the time constant of the first capacitor may be an average value of the characteristic value of the voltage of the first capacitor at different times
  • the preset error threshold may be based on the application scenario of the insulation resistance detection circuit 200 and This application scenario sets the exact requirements for the detection result, which will not be described in detail here in this application.
  • the insulation resistance detection circuit 200 may further include a ninth resistor and a third switch.
  • the second terminal of the third switch is connected to the ground, and the control terminal of the third switch is connected to the processor 204 .
  • the processor 204 can also be used to: control the third switch to be closed and open; and according to the first voltage waveform obtained by the first voltage dividing branch 201 in the first state and the second state after reaching the next switching time , the second voltage waveform obtained by the second voltage dividing branch 202 and the voltage waveform across the ninth resistor when the third switch is closed to calculate the parallel resistance value of the first resistor and the second resistor.
  • the parallel resistance value can be used to determine whether an insulation resistance fault occurs in the device to be detected.
  • the insulation resistance detection circuit 200 may further include a memory for storing the first voltage waveform and the second voltage waveform.
  • FIG. 4 a circuit structure diagram of an insulation resistance detection circuit provided by an embodiment of the present application.
  • the insulation resistance detection circuit may include a state control unit, a first voltage dividing branch, a second voltage dividing branch and a processor.
  • switches K1 and K2 and resistors R3 and R4 are included.
  • the first end of R3 is connected to the positive HVDC+ of the power supply of the device to be detected
  • the second end of R3 is connected to the first end of K1
  • the second end of K2 is connected to the ground
  • the first end of K2 is connected to the ground
  • the second end of K2 is connected to the ground
  • the second end of K2 is connected to the ground.
  • the second end is connected to the first end of R4, the second end of R4 is connected to the negative HVDC- of the power supply of the device to be detected, and the control ends of K1 and K2 are both connected to the processor.
  • a fifth resistor R5 and a sixth resistor R6 are included in the first voltage dividing branch.
  • One end of R5 is connected to the positive pole of the power supply, the second end of R5 is connected to the first end of R6 and the processor respectively, and the second end of R6 is connected to the ground and the processor. Wherein, both ends of R6 output the first voltage waveform.
  • a seventh resistor R7 and an eighth resistor R8 are included in the second voltage dividing branch.
  • the first end of R7 is connected to the ground and the processor, the second end of R7 is connected to the first end of R8 and the processor respectively, and the second end of R8 is connected to the negative pole of the power supply.
  • both ends of R7 output the second voltage waveform.
  • the processor is respectively connected with both ends of R6, both ends of R7, the control end of K1, the control end of K2 and the memory.
  • a and B are used as single-phase input terminals, which are respectively connected to the positive HVDC+ of the power supply of the device to be detected and the negative HVDC- of the power supply, and the energy from the left Transmit right.
  • C1 is the safety capacitor between the positive electrode and the ground of the power supply of the device to be detected
  • C2 is the safety capacitor between the negative electrode and the ground of the power supply of the device to be detected
  • R1 is the insulation between the positive electrode and the ground of the power supply of the device to be detected.
  • Resistance, R2 is the insulation resistance between the negative pole of the power supply of the device to be detected and the ground.
  • K1 closed and K2 open as switch state 1
  • K1 open and K2 closed as switch state 2
  • K1 and K2 are switched between switch state one and switch state two under the control of the processor.
  • the processor sends a first control signal to K1 and K2, and K1 and K2 are in switch state one in response to the first control signal.
  • the first capacitor C1 is discharged through R1, R5, R6 and R3, and the second capacitor C2 is discharged through R2, R7 and R2.
  • R8 is charged, and the processor obtains the first voltage waveform through the port connected with R6 and the second voltage waveform through the port connected with R7.
  • the processor calculates the characteristic value of the first capacitor voltage at different times within the set time period before the current time according to the first voltage waveform obtained at the current time, and/or calculates the voltage before the current time according to the second voltage waveform obtained before the current time.
  • the characteristic value of the second capacitor voltage at different times within the set time period is set to determine the next switching time. If the difference between any two adjacent voltage characteristic values in the first capacitor voltage characteristic values at different times is less than or equal to the preset error threshold, and/or any two adjacent voltage characteristic values in the second capacitor voltage characteristic values at different times When the difference between the values is less than or equal to the preset error threshold, it can be determined that the resistance value of the first resistor and the resistance value of the second resistor have not changed before the current moment.
  • the time constant of the first capacitor and/or the time constant of the second capacitor calculated according to the second voltage waveform obtained at the current moment determines the next switching moment, and when the next switching moment is reached, a second switching moment is sent to K1 and K2.
  • the control signal controls K1 and K2 to switch from switch state one to switch state two. If the difference between any two adjacent voltage characteristic values in the first capacitor voltage characteristic values at different times is greater than the preset error threshold, and/or the difference between two adjacent voltage characteristic values in the second capacitor voltage characteristic values at different times When the difference is greater than the preset error threshold, it can be determined that the resistance value of the first resistor and the resistance value of the second resistor have changed before the current moment, the current moment can be determined as the next switching moment, and a second control signal is sent to K1 and K2, Control K1 and K2 to switch from switch state one to switch state two.
  • the first resistance R1 is the insulation resistance between the positive pole of the power supply and the ground
  • the second resistance R2 is the insulation resistance between the negative pole of the power supply and the ground
  • the resistance of the first resistance R1 and the resistance of the second resistance R2 are determined by It is used to determine whether the insulation resistance fault occurs in the device to be tested.
  • first capacitor C1 and the second capacitor C2 are connected in series between the positive pole HVDC+ of the power supply to be detected and the negative pole HVDC- of the power supply.
  • the resistance value of the first resistor R1 connected in parallel with the first capacitor C1 changes, , the voltage across the first capacitor C1 changes, while the voltage value between the positive HVDC+ of the power supply and the negative HVDC- of the power supply remains unchanged, and the voltage across the second capacitor C2 will also change accordingly. Therefore, it is possible to detect different moments.
  • the first capacitor voltage characteristic value or the second capacitor voltage characteristic value at different times can determine whether the resistance value of the first resistor and the resistance value of the second resistor change.
  • the calculated characteristic value of the first capacitor voltage at different times is: The difference between the voltage characteristic value at the moment corresponding to the resistance value of the first resistor R1 and the voltage characteristic value calculated at any adjacent moment is small, resulting in detection errors.
  • the first capacitor voltage characteristic value at different times and the second capacitor voltage characteristic value at different times can be calculated at the same time. The characteristic value of the capacitor voltage is used to accurately determine whether the resistance value of the first resistor R1 and the resistance value of the second resistor R2 have changed before the current moment.
  • the characteristic value of the voltage of the first capacitor is the time constant of the first capacitor
  • the calculated voltage of the first capacitor at different times can be calculated.
  • the average value of the eigenvalues is used as the time constant of the first capacitor, and the next switching moment is calculated.
  • the next switching time may be the time corresponding to the moment when K1 and K2 are switched to the switch state as soon as the preset time period elapses.
  • the preset duration is 3 to 5 duration constants.
  • the processor uses the above-mentioned switching time determination methods K1 and K2 to turn on and off, and obtain the first voltage waveform and the second voltage waveform when K1 and K2 are in switching state 1 and switching state 2. , determine the resistance value of the first resistor R1 and the resistance value of the second resistor R2.
  • the current moment can be determined as the next switching moment, and the resistance of the first resistor R1 and the second resistor R2 at the next switching moment can be obtained as soon as possible.
  • the corresponding first voltage waveform and second voltage waveform are used, and the obtained first voltage waveform and second voltage waveform are used to calculate the resistance value of the first resistor R1 and the resistance value of the second resistor R2, and according to the first voltage waveform and the second voltage waveform.
  • the resistance of a resistor R1 and a second resistor R2 determine whether the device to be tested is faulty.
  • a shutdown command is sent to the device to be detected, and the shutdown command is used to instruct the device to be detected to disconnect the power supply from the load, thereby ensuring the safety of the operation to be detected.
  • R5 and R6 are connected in series with the first capacitor C1, and R7 and R9 are connected in parallel with the second capacitor C2. Therefore, the value corresponding to the first moment in the first voltage waveform across R6 is the same as that of the first capacitor C1.
  • the value corresponding to the first moment in the voltage waveform at both ends presents a ratio relationship
  • the value corresponding to the first moment in the second voltage waveform across R7 and the value corresponding to the first moment in the voltage waveform across the first capacitor C2 presents a ratio relationship. Therefore, for ease of understanding, the following describes the calculation process of the voltage characteristic value of the first capacitor at different times by taking the voltage waveforms across the first capacitor C1 and the second capacitor C2 as an example.
  • the processor sends a first control signal to the control terminals of K1 and K2, and K1 and K2 are in switch state one in response to the first control signal.
  • the first capacitor C1 discharges through R1, R5, R6 and R3, and the second capacitor C2 passes through R2, R7 and R8 charge.
  • the voltage U1 across the first voltage C1 and the voltage U2 across the second voltage C2 satisfy the common relationship between capacitor charging and discharging:
  • V0 and V2 are the first voltage value and the second voltage value when K1 and K2 are switched to the switching state, respectively, U1st and U2st are the value of the two ends of the first capacitor and the second voltage when K1 and K2 are switched to the second state, respectively. value across the capacitor.
  • ⁇ 1 and ⁇ 2 are the time constant of the first capacitor C1 and the time constant of the second capacitor C2, respectively.
  • t is the corresponding time after the first capacitor C1 and the second capacitor C2 are switched to the first state.
  • R5+R6), ⁇ 2 C2* (R2
  • C1 is the capacitance of the first capacitor C1
  • C2 is the capacitance of the first capacitor C2.
  • the resistance value of the first resistor R1 and the resistance value of the second resistor R2 do not change before the current time, as shown in FIG. 5 , then the first voltage waveform before the current time and the second voltage waveform obtained at the current time The voltage waveform changes with a fixed regularity.
  • U1'(t) is the voltage waveform corresponding to the first capacitor C1 when K1 and K2 are in the second state
  • U2'(t) is the voltage waveform corresponding to the second capacitor C2 when K1 and K2 are in the second state.
  • the first resistor R1 When the resistance value of the first resistor R1 and the resistance value of the second resistor R2 change, as shown in FIG. 6 or FIG. 7 , before the resistance value of the first resistor R1 and the resistance value of the second resistor R2 change, the first resistor R1 The voltage waveform and the second voltage waveform change according to the first law, and after the resistance value of the first resistor R1 and the resistance value of the second resistor R2 change, the first voltage waveform and the second voltage waveform change according to the second law.
  • the abrupt change in the insulation state means that the resistance value of the first resistor R1 and the resistance value of the second resistor R2 change.
  • the process of determining the voltage characteristic value of the first capacitor will be described in detail.
  • X is the corresponding acquisition time after K1 is switched to switch state 1.
  • X(i) represents the time when the i-th point is collected
  • X(i-1) represents the time when the i-1-th point is collected
  • M is the set collection point
  • the collection point M is updated in real time, and the collection point M and the collection time X(i) are accumulated through the new collection point M and collection time X(i), and the values in the above formula are updated to obtain the following formula:
  • N is a natural number.
  • the set number of acquisition points can be obtained from the first voltage waveform obtained before the current moment.
  • the time constant ⁇ 2 of the second capacitor can be calculated and obtained by using the second voltage waveform obtained before the current moment.
  • the above method is used to calculate the characteristic value of the first capacitor voltage at different times in the set time period before the current time, and calculate the characteristic value of the second capacitor voltage at different times in the set time period before the current time.
  • the insulation resistance detection circuit provided by the embodiment of the present application also has several other structures. The principles of other circuit structures are the same, and will not be described in detail in this application.
  • FIG. 8 a circuit structure diagram of another insulation resistance detection circuit provided by an embodiment of the present application.
  • the insulation resistance detection circuit may include a state control unit, a first voltage dividing branch, a second voltage dividing branch, a processor, a ninth resistor R9 and a third switch K3.
  • switches K1 and K2 and resistors R3 and R4 are included.
  • the first end of R3 is connected to the positive HVDC+ of the power supply of the device to be detected
  • the second end of R3 is connected to the first end of K1
  • the second end of K2 is connected to the ground
  • the first end of K2 is connected to the ground
  • the second end of K2 is connected to the ground
  • the second end of K2 is connected to the ground.
  • the second end is connected to the first end of R4, the second end of R4 is connected to the negative HVDC- of the power supply of the device to be detected, and the control ends of K1 and K2 are both connected to the processor.
  • a fifth resistor R5 and a sixth resistor R6 are included in the first voltage dividing branch.
  • One end of R5 is connected to the positive pole of the power supply, the second end of R5 is connected to the first end of R6 and the processor respectively, and the second end of R6 is connected to the ground and the processor. Wherein, both ends of R6 output the first voltage waveform.
  • a seventh resistor R7 and an eighth resistor R8 are included in the second voltage dividing branch.
  • the first end of R7 is connected to the ground and the processor, the second end of R7 is connected to the first end of R8 and the processor respectively, and the second end of R8 is connected to the negative pole of the power supply.
  • both ends of R7 output the second voltage waveform.
  • the processor is respectively connected with both ends of R6, both ends of R7, the control end of K1, the control end of K2, the two ends of R9, the control end of K3 and the memory.
  • the first end of R9 is connected to the positive pole of the power supply and the processor, respectively, the second end of R9 is connected to the first end of K3 and the processor, the second end of K3 is connected to the ground, and the control end of K3 is connected to the processor.
  • the resistance of R3 is less than the preset threshold.
  • a and B are used as single-phase input terminals, which are respectively connected to the positive HVDC+ of the power supply of the device to be detected and the negative HVDC- of the power supply, and the energy from the left Transmit right.
  • C1 is the safety capacitor between the positive electrode and the ground of the power supply of the device to be detected
  • C2 is the safety capacitor between the negative electrode and the ground of the power supply of the device to be detected
  • R1 is the insulation between the positive electrode and the ground of the power supply of the device to be detected.
  • Resistance, R2 is the insulation resistance between the negative pole of the power supply of the device to be detected and the ground.
  • K1 closed and K2 open as switch state 1
  • K1 open and K2 closed as switch state 2
  • K1 open and K2 closed as switch state 2
  • the processor sends a first control signal to K3, K3 closes in response to the first control signal, and sends a second control signal to K1 and K2, K1 and K2 respond to the second control signal, K1 and K2 are in switch state one, and the first
  • the capacitor C1 is discharged through R1, R5, R6, R9 and R3, the second capacitor C2 is charged through R2, R7 and R8, and the processor obtains the first and second voltage waveforms through the ports connected to R6 and R7.
  • the processor calculates the characteristic value of the first capacitor voltage at different times within the set time period before the current time according to the first voltage waveform obtained at the current time, and/or calculates the voltage before the current time according to the second voltage waveform obtained before the current time.
  • the difference between any two adjacent voltage characteristic values in the first capacitor voltage characteristic values at different times is greater than the preset error threshold, and/or the difference between any two adjacent voltage characteristic values in the second capacitor voltage characteristic values at different times
  • the difference is greater than the preset error threshold, it can be determined that the resistance value of the first resistor and the resistance value of the second resistor have changed before the current moment, and the current moment can be determined as the next switching moment.
  • the calculated average value of the first capacitor voltage characteristic value at different times may be used as the time constant of the first capacitor to calculate the next switching time.
  • K3 can send a second control signal, K3 is closed in response to the second control signal, and the voltage waveform across R9 is detected, and the voltage waveform across R9 is used to determine the first resistance and the second resistance.
  • the first resistance is the insulation resistance between the positive pole of the power supply and the ground
  • the second resistance is the insulation resistance between the negative pole of the power supply and the ground
  • the parallel resistance of the first resistance and the second resistance can be used to determine whether insulation occurs Resistor failure.
  • the voltage waveform at both ends of R9 calculates the parallel resistance value of the first resistor and the second resistor, and determines the insulation condition of the device to be detected by the parallel resistance value.
  • a shutdown command is sent to the device to be detected, and the shutdown command can be used to instruct the device to be detected to disconnect the power supply from the load, thereby protecting the operation safety of the device to be detected.
  • R5 and R6 are connected in series with the first capacitor C1, and R7 and R8 are connected in parallel with the second capacitor C2. Therefore, the value corresponding to the first moment in the first voltage waveform across R6 and the first capacitor C1
  • the value corresponding to the first moment in the voltage waveform at both ends presents a ratio relationship
  • the value corresponding to the first moment in the second voltage waveform across R7 and the value corresponding to the first moment in the voltage waveform across the first capacitor C2 presents a ratio relationship. Therefore, for ease of understanding, the following describes the calculation process of the voltage characteristic value of the first capacitor at different times by taking the voltage waveforms across the first capacitor C1 and the second capacitor C2 as an example.
  • the processor sends a first control signal to the control terminals of K1 and K2, K1 and K2 are in switch state one in response to the first control signal, at this time the first capacitor C1 discharges through R1, R5, R6 and R3, and the second capacitor C2 passes through R2, R7 and R8 charge.
  • the first capacitor voltage characteristic value and/or the second capacitor voltage characteristic value at different times determine the next switching time.
  • a second control signal can be sent to K3, and K3 is closed in response to the second control signal.
  • the Y capacitor Safety Fixed capacitor
  • Y can be discharged through R9, and Y can be calculated by using the above calculation time constant.
  • C3 is the capacitance value of the Y capacitor.
  • R sum is the parallel resistance value of multiple resistors connected in parallel with the Y capacitor.
  • the parallel resistance value of R1 and R2 can be calculated, and according to the parallel resistance value of R1 and R2, it can be determined whether the insulation failure of the device to be detected has occurred, and after determining the device to be detected. In the event of insulation failure, disconnect the power supply of the device to be detected and the load to ensure the safe operation of the device to be detected.
  • the second preset resistance threshold can be set according to the application scenario of the device to be detected, which is not described in detail here in this application.
  • the resistance value of R9 can be set to be smaller than a preset threshold value, and the preset threshold value is smaller than the first voltage dividing branch, the second voltage dividing path, R1, R2,
  • the resistance value of any resistor including R3 and R4 realizes that when K3 is closed, R sum ⁇ R 9 .
  • the value of the Y capacitor can be obtained through the calculated ⁇ 3, and then use the above method to calculate the parallel resistance to calculate the first A resistor and a second resistor are connected in parallel.
  • the insulation resistance detection circuit provided by the embodiment of the present application also has several other structures. The principles of other circuit structures are the same, and will not be described in detail in this application.
  • an embodiment of the present application also provides a monitoring device for a high-voltage system.
  • the monitoring system 900 may include a switch module 901 , an alarm module 902 , a communication module 903 and the Insulation resistance detection circuit 200 .
  • the insulation resistance detection circuit 200 can be connected to the communication module connection 903 , and the communication module 903 can be connected to the alarm module 902 .
  • the switch module 901 can be used to connect between the power supply and the load of the high-voltage system.
  • the insulation resistance detection circuit 200 is used to detect the resistance of the first resistance between the positive pole of the power supply and the ground and the resistance of the second resistance between the negative pole of the power supply and the ground, and compare the resistance of the first resistance with the resistance of the second resistance. The resistance value is sent to the communication module 903 .
  • the communication module 903 can be used to notify the alarm module 902 to give an alarm when it is determined that the resistance value of the first resistor or the resistance value of the second resistor is smaller than the first preset resistance threshold; When the resistance value is less than the second preset resistance threshold value, the control switch module 901 is turned off.
  • the monitoring device 900 of the high-voltage system can be connected to the high-voltage system of the electric vehicle, for monitoring the operation of the high-voltage system of the electric vehicle and protecting the operation safety of the high-voltage system.
  • the embodiment of the present application also provides an insulation resistance detection method, as shown in FIG. 10
  • the image processing method provided by the embodiment of the present application is as follows. The method may be executed by the processor shown in FIG. 2 , or may be executed by other processors in communication with the insulation resistance detection circuit shown in FIG. 2 .
  • the processor acquires a first voltage waveform corresponding to the first capacitor and a second voltage waveform corresponding to the second capacitor.
  • the first capacitance is the capacitance between the positive pole of the power supply of the device to be detected and the ground
  • the second capacitance is the capacitance between the negative pole of the power supply and the ground.
  • the processor can directly obtain the first voltage waveform and the second voltage waveform through the first capacitor and the second capacitor; when the first voltage waveform and When the corresponding voltage value in the second voltage waveform is large, the voltage values in the first voltage waveform and the second voltage waveform are difficult to meet the requirements of the processor for the voltage value, and a voltage sensor can be used to connect the first voltage and the second voltage, A first voltage waveform and a second voltage waveform that meet the processor voltage requirements are obtained.
  • a voltage divider circuit may be used to divide the voltage across the first capacitor and the second capacitor to obtain the divided first voltage. waveform and the second voltage waveform.
  • the processor controls the first capacitor and the second capacitor to switch between the first state or the second state.
  • the first state may be, but not limited to, the first capacitor is charged and the second capacitor is discharged
  • the second state may be, but not limited to, the first capacitor is discharged and the second capacitor is charged.
  • a control signal may be sent to a switch tube or a relay connected to the first capacitor and the second capacitor, so as to control the first capacitor and the second capacitor to switch between the first state and the second state.
  • first capacitor and the second capacitor are connected in series between the positive electrode and the negative electrode of the power supply of the device to be detected, when the first capacitor and the second capacitor are both discharged, the voltage at both ends of the first capacitor and the second capacitor are two.
  • the voltage of the terminal is small, and the voltage between the positive electrode and the negative electrode of the power supply to be detected is relatively high, which may cause the breakdown of the first capacitor and the second capacitor at this time, resulting in leakage. Therefore, the first capacitor and the second capacitor will not be turned on or off at the same time.
  • the processor calculates, according to the first voltage waveform obtained at the current moment, the characteristic values of the first capacitor voltage at different times within the set time period before the current moment; The characteristic value of the second capacitor voltage at different times within the set time period before the time.
  • the first capacitor voltage characteristic value may be, but not limited to, the time constant of the first capacitor and/or the voltage waveform state of the first capacitor.
  • the second capacitor voltage characteristic value may be, but not limited to, the time constant of the second capacitor or the voltage waveform state of the second capacitor.
  • S1004 The processor determines the next switching time according to the characteristic value of the first capacitor voltage at different times and/or the characteristic value of the second capacitor voltage at different times.
  • the average value of the first capacitor voltage characteristic value at different times is used as the time constant of the first capacitor.
  • S1005 The processor controls the first capacitor and the second capacitor to perform state switching when the next switching time is reached.
  • a control command is sent to the switch tube or relay connected to the first capacitor and the second capacitor, and the switch tube or the relay is controlled to control the first capacitor and the second capacitor to switch states.
  • the processor may continue to acquire the first voltage waveform and the second voltage waveform, and continue to acquire the first voltage waveform and the second voltage waveform to determine the resistance of the first resistor and the resistance of the second resistor.
  • the first resistance is the insulation resistance between the positive pole of the power supply and the ground
  • the second resistance is the insulation resistance between the negative pole of the power supply and the ground
  • the resistance of the first resistance and the resistance of the second resistance are used to determine whether the occurrence of Insulation resistance failure.
  • the resistance value of the first resistor and the resistance value of the second resistor do not change, record the first capacitance and the second capacitance at each The first voltage value and the second voltage value corresponding to the first voltage waveform and the second voltage waveform at the switching time; and when it is determined that the difference between any two adjacent voltage characteristic values is greater than the preset error threshold, the resistance of the first resistor is determined.
  • the value and the resistance value of the second resistor change, delete the first voltage value and the second voltage value recorded before the current moment, and re-record the first voltage waveform and the first voltage waveform and the second voltage waveform at each subsequent switching moment of the first capacitor and the second capacitor.
  • the first voltage value and the second voltage value corresponding to the two voltage waveforms; the resistance value of the first resistor and the resistance value of the second resistor are determined by using the recorded first voltage value and the second voltage value.
  • the first preset insulation threshold may be set according to the requirements of the device to be detected for the insulation resistance, which will not be described in detail in this application.
  • the current moment can be determined as the next switching moment, so as to obtain the voltage waveform corresponding to the resistance value of the first resistor and the resistance value of the second resistor as soon as possible, and use the obtained voltage waveform to calculate the resistance value of the first resistor and the resistance of the second resistor, so that when the resistance of the first resistor and the resistance of the second resistor cannot meet the insulation resistance requirements of the device to be detected, the connection between the power supply and the load of the device to be detected can be disconnected, thereby avoiding electric shock The occurrence of an accident ensures the safe operation of the device to be detected.
  • the states of the first capacitor and the second capacitor can be switched, and the first voltage can be obtained after the state switching is obtained.
  • the first and second voltage values U1 st , U2 st , U1' st and U2' st corresponding to each switching moment in the waveform and the second voltage waveform.
  • V HV is the voltage between the positive pole of the power supply to be detected and the negative pole of the power supply
  • the resistance of R5 and the resistance of R8 can be the same
  • the resistance of R6 and R7 can be the same
  • the above two equations can be obtained.
  • the processor After calculating the resistance value of the first resistor and the resistance value of the second resistor, the processor determines the current resistance value of the first resistor when it is determined that the resistance value of the first resistor or the resistance value of the second resistor is smaller than the first preset insulation threshold. If the resistance value and the resistance value of the second resistor cannot meet the insulation resistance requirements of the device to be detected, a shutdown command is sent to the device to be detected, and the shutdown command is used to instruct the device to be detected to disconnect the power supply from the load.
  • the first resistance representing the insulation of the device to be detected can be directly calculated. and the parallel resistance of the second resistor.
  • the resistance of the charging and discharging path includes the parallel resistance of the first resistance and the second resistance and the resistance of the insulation resistance detection circuit, after the When the resistance of the insulation resistance detection circuit is known, the parallel resistance value of the first resistance and the second resistance can be calculated.
  • the processor After calculating the parallel resistance value of the first resistance and the second resistance, the processor determines that the parallel resistance value of the first resistance and the second resistance cannot satisfy the insulation resistance of the device to be detected when the parallel resistance is determined to be less than the second preset insulation threshold.
  • a shutdown command is sent to the device to be detected, and the shutdown command is used to instruct the device to be detected to disconnect the power supply from the load.
  • the second preset insulation threshold may be set according to the requirements of the device to be detected for the insulation resistance, which will not be described in detail here in this application.
  • FIG. 11 Based on the description described in FIG. 10 , reference may be made to the schematic flowchart of the method for detecting insulation resistance shown in FIG. 11 .
  • the detection process of the insulation resistance is described in detail by taking the determination of the next switching time according to the characteristic value of the first capacitor voltage at different time as an example.
  • S1101 Acquire a first voltage waveform and a second voltage waveform.
  • S1102 Using the first voltage waveform obtained at the current time, calculate the characteristic value of the first capacitor voltage at different times within a set time period before the current time.
  • S1103 Detect whether the resistance value of the first resistor and the resistance value of the second resistor change by using the characteristic value of the voltage of the first capacitor at different times, and if so, execute S1104, otherwise, execute S1106.
  • S1104 Determine the current time as the next switching time.
  • S1106 When it is determined that the resistance value of the first resistor has not changed, calculate the time constant of the first capacitor, and use the time constant of the first capacitor to calculate the next switching time.
  • S1108 Store the first voltage value and the second voltage value at the current moment.
  • an embodiment of the present application further provides an insulation resistance detection device, the insulation resistance detection device 1200 .
  • the insulation resistance detection device 1200 may include an acquisition unit 1201 , a processing unit 1202 and a calculation unit 1203 .
  • the obtaining module 1201 can be used to obtain the first voltage waveform and the second voltage waveform.
  • the first voltage is the voltage across the first capacitor between the positive pole of the power supply to be detected and the ground
  • the second voltage is the voltage across the second capacitor between the negative pole of the power supply and the ground.
  • the processing unit 1202 may be used to control the first capacitor and the second capacitor to switch between the first state or the second state. The first state is when the first capacitor is charged and the second capacitor is discharged, and the second state is when the first capacitor is discharged and the second capacitor is charged.
  • the calculation unit 1203 can be used to calculate the characteristic value of the first capacitor voltage at different times within the set time period before the current moment according to the first voltage waveform obtained by the acquisition module 1201 at the current moment;
  • the second voltage waveform is used to calculate the second capacitor voltage characteristic values at different times within the set time period before the current time.
  • the processing unit 1202 may also be configured to determine the next switching moment of the first capacitor and the second capacitor according to the first capacitor voltage characteristic value at different times and/or the second capacitor voltage characteristic value at different times output by the computing unit 1203, and When the next switching moment is reached, the first capacitor and the second capacitor are controlled to perform state switching.
  • the acquired second voltage waveform is used to calculate the characteristic value of the second capacitor voltage at different times within the set time period before the current time.
  • the obtaining unit 1201 is further configured to: continue to obtain the first voltage waveform and the second voltage waveform after controlling the first capacitor and the second capacitor to perform state switching when the next switching time is reached.
  • the processing unit 1202 is further configured to determine the resistance value of the first resistor and the resistance value of the second resistor according to the first voltage waveform and the second voltage waveform continuously obtained by the obtaining unit 1201 .
  • the first resistance is the insulation resistance between the positive pole of the power supply and the ground
  • the second resistance is the insulation resistance between the negative pole of the power supply and the ground.
  • the resistance of the first resistance and the resistance of the second resistance are used to determine whether insulation resistance occurs. Fault.
  • the processing unit 1202 is specifically configured to: compare any two adjacent voltage characteristic values of the first capacitor voltage characteristic values at different times, and/or compare any adjacent voltage characteristic values of the second capacitor voltage characteristic values at different times. The two voltage characteristic values are compared; when it is determined that the difference between any two adjacent voltage characteristic values is greater than the preset error threshold, the current moment is determined as the next switching moment; and when it is determined that any two adjacent voltage characteristic values are less than or When equal to the preset error threshold, the time constant of the first capacitor and/or the time constant of the second capacitor is determined, and the next switching moment is determined according to the time constant of the first capacitor and/or the time constant of the second capacitor.
  • the processing unit 1202 is specifically configured to: when it is determined that any two adjacent voltage characteristic values are less than or equal to the preset error threshold, record the first voltage waveform and the first voltage waveform of the first capacitor and the second capacitor at each switching moment. The first voltage value and the second voltage value corresponding to the two voltage waveforms; and when it is determined that the difference between any two adjacent voltage characteristic values is greater than the preset error threshold, the first voltage value and the second voltage value recorded before the current moment are deleted. , and re-record the first voltage value and the second voltage value corresponding to the first voltage waveform and the second voltage waveform at each subsequent switching moment of the first capacitor and the second capacitor; use the recorded first voltage value and second voltage value.
  • the voltage value determines the resistance value of the first resistor and the resistance value of the second resistor.
  • the processing unit 1202 is further configured to: when it is determined that the resistance value of the first resistor or the resistance value of the second resistor is less than the first preset insulation threshold, send a shutdown instruction to the device to be detected, where the shutdown instruction is used to indicate the pending insulation threshold.
  • the detection device disconnects the power supply from the load.
  • the processing unit 1202 is further configured to: determine the parallel resistance value of the first resistor and the second resistor according to the first voltage waveform and the second voltage waveform obtained by the obtaining unit 1201; When the insulation threshold is set, a shutdown command is sent to the device to be detected, and the shutdown command is used to instruct the device to be detected to disconnect the power supply from the load.
  • the first capacitor voltage characteristic value includes one or more of the following: the time constant of the first capacitor and the voltage waveform state of the first capacitor;
  • the second capacitor voltage characteristic value includes one or more of the following: the time constant of the second capacitor The constant and the voltage waveform state of the second capacitor; the waveform state of the first capacitor represents the fluctuation trend of the voltage across the first capacitor, and the waveform state of the second capacitor represents the waveform trend of the two ends of the second capacitor.
  • the division of modules in the embodiments of the present application is schematic, and is only a logical function division. In actual implementation, there may be other division methods.
  • the functional modules in the various embodiments of the present application may be integrated into one processing unit. In the device, it can also exist physically alone, or two or more modules can be integrated into one module.
  • the above-mentioned integrated modules can be implemented in the form of hardware, and can also be implemented in the form of software function modules.
  • An embodiment of the present application provides a computer-readable storage medium storing a computer program, where the computer program includes instructions for executing the foregoing method embodiments.
  • the embodiments of the present application provide a computer program product containing instructions, which, when executed on a computer, cause the computer to execute the above method embodiments.
  • the embodiments of the present application may be provided as a method, a system, or a computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.
  • computer-usable storage media including, but not limited to, disk storage, CD-ROM, optical storage, etc.
  • These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions
  • the apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

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Abstract

本申请提供一种绝缘电阻检测电路、方法、装置及其存储介质,用于检测绝缘电阻是否发生故障,包括:状态控制单元、第一分压支路、第二分压支路和处理器;状态控制单元跨接在待检测装置电源的正极和负极之间;第一分压支路与第一电容并联,得到第一电压波形;第二分压支路与第二电容并联,得到第二电压波形;处理器与状态控制单元、第一分压支路和第二分压支路连接,根据当前时刻的第一电压波形和第二电压波形,计算当前时刻之前设定时长内不同时刻的第一电容电压特征值和不同时刻的第二电容电压特征值;根据不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确定下一切换时刻,在下一切换时刻控制状态控制单元进行状态切换。

Description

一种绝缘电阻检测电路、方法、装置及其存储介质 技术领域
本申请涉及电动汽车技术领域,特别涉及一种绝缘电阻检测电路、方法、装置及其存储介质。
背景技术
电动汽车,与传统车相比,电动汽车高压供电系统的供电电压动辄几百伏(V)。随着汽车产业的快速发展及电动汽车(battery electric vehicle,BEV)的大量应用,高压供电系统的绝缘电阻检测在汽车安全及维修中发挥着不可替代的作用。
高压供电系统中电源的正极与电源的负极的电压最高,一旦电源的正极与地之间的绝缘电阻或者电源的负极与地之间的绝缘电阻发生故障,会发生漏电较大的问题,并在绝缘电阻故障处漏电,严重时会发生人员触电。因此,高压供电系统的绝缘电阻是否发生故障的检测主要是检测高压供电系统中的电源的正极与地之间的绝缘电阻以及电源的负极与地之间的绝缘阻值,当确定两个绝缘电阻中的任一绝缘电阻的阻值小于高压供电系统对绝缘电阻的阻值的需求时,则需要断开高压供电系统中的电源的与负载的连接,以保证高压供电系统的安全运行。
实际应用中,绝缘电阻的检测方式主要有两种,一种是交流信号注入法,另一种是外接电阻法。交流信号注入法,是指在高压供电系统的电源的正负极之间注入一定频率的交流信号,通过测量高压供电系统的反馈,获得高压供电系统的绝缘电阻的阻值。但是该检测方式应用时,注入的交流信号容易对高压供电系统造成干扰,影响系统正常工作。外接电阻法,即在高压供电系统的电源的正负极之间接入开关和一系列电阻,通过控制开关的通断,获得开关处于不同状态绝缘电阻上的电压值,通过列出绝缘电阻电压的变化方程,两个方程联立解出高压供电系统中的电源的正极对地和负极对地的绝缘电阻值,判断电源的正极和负极对地的绝缘电阻的阻值情况。
实际使用时,采用外接电阻法计算电源的正极和负极对地的绝缘电阻值时,开关以固定周期断开或者闭合,当电源的正负极与地之间的绝缘电阻发生故障时,仍然以固定周期检测绝缘电阻,将会导致高压供电系统无法及时排查出绝缘电阻的故障。因此,当绝缘电阻故障无法满足高压供电系统的绝缘需求时,采样上述检测方法无法及时进行故障报警或者处理,影响了高压供电系统的安全运行,严重甚至会造成人员触电。
因此,现有的绝缘电阻的检测方式,无法及时检测出绝缘电阻发生故障,影响了高压供电系统的安全运行。
发明内容
本申请提供一种绝缘电阻检测电路、方法、装置及其存储介质,用以快速检测出绝缘电阻是否发生故障,保证高压供电系统的安全运行。
第一方面,本申请实施提供一种绝缘电阻检测电路,该绝缘电阻检测电路可以与待检测装置连接,用于检测待检测装置电源的正极和负极之间的绝缘电阻,并判断待检测装置是否发生绝缘失效,具体地,该绝缘电阻检测电路可以包括:状态控制单元、第一分压支 路、第二分压支路和处理器。
其中,状态控制单元跨接在待检测装置的电源的正极和负极之间,处理器分别与状态控制单元、第一分压支路和第二分压支路连接。
其中,状态控制单元用于在处理器的控制下在第一状态或第二状态之间切换。状态控制单元处于第一状态时第一电容充电且第二电容放电,状态控制单元处于第二状态时第一电容放电且第二电容充电,第一电容为电源的正极与地之间的电容,第二电容为电源的负极与地之间的电容。第一分压支路用于与第一电容并联,并用于对第一电容两端的电压进行分压,得到第一电压波形。第二分压支路用于与第二电容并联,并用于对第二电容两端的电压进行分压,得到第二电压波形。处理器用于:根据当前时刻已得到的第一电压波形,计算当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据当前时刻已得到的第二电压波形,计算当前时刻之前的设定时长内不同时刻的第二电容电压特征值;并根据不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确定状态控制单元的下一切换时刻,并在到达下一切换时刻时控制状态控制单元进行状态切换。
采用上述电路结构,控制状态控制单元在第一状态和第二状态之间切换,实现控制第一电容和第二电容进行充放电,在第一电容和第二电容充电过程中,若电源的正极负极之间的绝缘电阻未发生变化,则第一电压波形和第二电压波形以规定的规律变化,若电源的正极负极之间的绝缘电阻发生变化,则第一电压波形和第二电压波形的变化规律发生变化,因此可以通过计算不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,及时检测到绝缘电阻是否发生变化,以及在确定绝缘电阻发生变化时,改变切换时刻,从而尽快获取到当前时刻绝缘电阻对应波形来计算出绝缘电阻的阻值,从而在检测绝缘电阻的阻值不符合要求时,快速对待检测装置进行保护。
在一种可能的设计中,处理器还用于:根据在到达下一切换时刻之后在第一状态和第二状态时已得到的第一电压波形和已得到的第二电压波形,确定第一电阻的阻值和第二电阻的阻值;第一电阻为电源的正极与地之间的绝缘电阻,第二电阻为电源的负极与地之间的绝缘电阻,第一电阻和阻值和第二电阻的阻值用于确定是否发生绝缘电阻故障。
采用上述电路结构,可以根据到达下一切换时刻当前绝缘电阻在状态切换单元在第一状态和第二状态时对应的第一电压波形和第二电压波形计算出第一电压阻值和第二电阻的阻值,并利用第一电阻的阻值和第二电阻的阻值准确的判定待检测装置是否发生绝缘失效。
在一种可能的设计中,第一开关单元可以包括:状态控制单元包括:第一开关单元和第二开关单元。
其中,第一开关单元的第一端与电源的正极连接,第一开关单元的第二端与地连接。第二开关单元的第二端与电源的负极连接,第二开关单元的第二端与地连接。其中,第一开关单元闭合且第二开关单元断开时,状态控制单元处于第一状态;第一开关单元断开且第二开关单元闭合时,状态控制单元处于第二状态。
采用上述电路结构,可以通过控制第一开关单元和第二开关单元的工作状态分别控制第一电容和第二电容的充电或放电,从而实现精准的控制状态控制单元在第一状态和第二状态之间切换。
在一种可能的设计中,第一开关单元包括:第一开关和第三电阻。
其中,第三电阻的第一端与电源的正极连接,第三电阻的第二端与第一开关的第一端 连接。第一开关的第二端与地连接,第一开关的控制端与处理器连接。
采用上述电路结构,可以通过控制第一开关的工作状态,实现控制第一电容的充放电时刻,同时利用第三电阻进行限流,从而避免第一开关将电源的正极与地短路。
在一种可能的设计中,第二开关单元包括:第二开关和第四电阻。
其中,第二开关的第一端与地连接,第二开关的第二端与第四电阻的第一端连接,第二开关的控制端与处理器连接。第四电阻的第二端与电源的负极连接。
采用上述电路结构,可以通过控制第二开关的工作状态,实现控制第二电容的充放电时刻,同时利用第四电阻进行限流,从而避免第二开关将电源的负极与地短路。
在一种可能的设计中,第一分压支路可以包括:第五电阻和第六电阻。
具体地,第五电阻的一端与电源的正极连接,第五电阻的第二端分别与第六电阻的第一端和处理器连接。第六电阻的第二端与地和处理器连接。
采用上述电路结构,由于待检测装置电源的正极与地之间的电压较高,为了保证检测的准确度以及检测成本,第一分压支路上可以设置两个电阻,并获取阻值较少的电阻两端的第一电压进行检测,可以实现当第一电压发生波动时,可以准确的检测出来,保证检测的准确度。
在一种可能的设计中,第二分压支路可以包括:第七电阻和第八电阻。
具体地,第七电阻的第一端与地和处理器连接,第七电阻的第二端分别与第八电阻的第一端和处理器连接。第八电阻的第二端与电源的负极连接。
采用上述电路结构,由于待检测装置电源的负极与地之间的电压较高,为了保证检测的准确度以及检测成本,第二分压支路上可以设置两个电阻,并获取阻值较少的电阻两端的第二电压进行检测,可以实现当第二电压发生波动时,可以准确的检测出来,保证检测的准确度。
在一种可能的设计中,本申请实施例提供的绝缘电阻检测电路还包括:第九电阻和第三开关。
其中,第九电阻的第一端分别与电源的正极和处理器连接,第九电阻的第二端分别与第三开关的第一端和处理器连接,第九电阻的阻值小于预设阈值。第三开关的第二端与地连接,第三开关的控制端与处理器连接。
具体地,处理器还用于:控制第三开关闭合和断开;根据在到达下一切换时刻之后一时长内,第一分压支路已得到的第一电压波形、第二分压支路已得到的第二电压波形以及第三开关闭合时第九电阻两端的电压波形,计算第一电阻和第二电阻的并联阻值,并联阻值用于确定是否发生绝缘电阻故障。
采用上述电路结构,由于第一电阻和第二电阻串联在待检测装置电源的正极和负极之间,在第一电阻和第二电阻中的任一电阻发生故障时,均会造成影响待检测装置的安全运行,因此,可以通过检测第一电阻和第二电阻的并联电阻,确定待检测装置是否发生绝缘失效。由于无需计算出第一电阻的阻值和第二电阻的阻值,减少了处理器的计算量。
第二方面,本申请实施例提供了一种高压系统的监控装置,该高压系统监控装置可以与高压系统连接,用于监控高压系统的工作状态。具体地,该监控装置可以包括:开关模块、报警模块、通信模块和本申请实施例第一方面提供的绝缘电阻检测电路。
其中,绝缘电阻检测电路与通信模块连接,通信模块与报警模块连接。
其中,开关模块用于连接在高压系统的电源和负载之间。绝缘电阻检测电路用于检测 电源的正极与地之间的第一电阻的阻值和电源的负极与地之间的第二电阻的阻值,并将第一电阻的阻值和第二电阻的阻值发送给通信模块。通信模块用于在确定第一电阻的阻值或者第二电阻的阻值小于第一预设电阻阈值时,通知报警模块进行报警;以及在第一电阻的阻值或者第二电阻的阻值小于第二预设电阻阈值时,控制开关模块断开。
采用上述装置结构,可以及时检测到高压系统的绝缘电阻是否发生变化,以及在确定绝缘电阻发生变化时,通过报警模块进行报警,以提示工作人员对第一电阻和第二电阻进行更换,保证高压系统的运行安全。
第三方面,本申请实施例提供了一种绝缘电阻检测方法,该方法的执行主体可以是本实施例第一方面提供的绝缘电阻电路中的处理器或者与待检测装置通信连接的其它处理器,该方法具体包括以下步骤:获取第一电容对应的第一电压波形和第二电容对应的第二电压波形,第一电容为待检测装置电源的正极与地之间电容,第二电电容为电源的负极与地之间的电容;控制第一电容和第二电容在第一状态或第二状态之间切换,第一状态为第一电容充电且第二电容放电,第二状态为第一电容放电且第二电容充电;根据当前时刻已获取的第一电压波形,计算在当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据当前时刻已获取的第二电压波形,计算在当前时刻之前的设定时长内不同时刻的第二电容电压特征值;根据不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确定下一切换时刻;在到达下一切换时刻时控制第一电容和第二电容进行状态切换。
采用上述方法,可以利用不同时刻的第一电容电压特征值和不同时刻的第二电容电压特征值判定待检测装置的绝缘电阻的阻值是否发生变化,以及对第一电容和第二电容的状态切换时刻进行调整,由于在计算待检测装置的绝缘电阻的阻值需要得到绝缘电阻对应的第一电压波形和第二电压波形,可以采用上述方法,在绝缘电阻的阻值发生变化时,尽快得到绝缘电阻的阻值对应的电压波形,从而保证在绝缘电阻的阻值发生变化时,尽快检测出当前绝缘电阻的阻值是否满足待检测装置对绝缘的需求,从而判定待检测装置是否发生绝缘失效。
在一种可能的设计中,在到达下一切换时刻时控制第一电容和第二电容进行状态切换之后,还包括:
继续获取第一电压波形和第二电压波形;
根据继续获取的第一电压波形和第二电压波形,确定第一电阻的阻值和第二电阻的阻值,第一电阻为电源的正极与地之间的绝缘电阻,第二电阻为电源的负极与地之间的绝缘电阻,第一电阻的阻值和第二电阻的阻值用于确定是否发生绝缘电阻故障。
采用上述方法,在下一切换时刻切换第一电容和第二状态后,获取到当前时刻第一电阻的阻值和第二电阻的阻值对应的第一电压波形和第二电压波形,并利用该电压波形可以准确的计算出第一电阻的阻值和第二电阻的阻值。
在一种可能的设计中,根据不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确定第一电容和第二电容的下一切换时刻,包括:
将不同时刻的第一电容电压特征值中任意相邻两个电压特征值进行比较,和/或将不同时刻的第二电容电压特征值中任意相邻两个电压特征值进行比较;在确定任意相邻两个电压特征值之差大于预设误差阈值时,将当前时刻确定为下一切换时刻;以及在确定任意相邻两个电压特征值小于或等于预设误差阈值时,确定第一电容的时间常数和/或第二电容的 时间常数,并根据第一电容的时间常数和/或第二电容的时长常数,确定下一切换时刻。
采用上述方法,由于第一电容和第二电容分别通过第一电阻和第二电阻进行充电和放电,当第一电阻的阻值和第二电阻的阻值未发生变化,则第一电压波形和第二电压波形以固定规律进行变化,计算的不同时刻的第一电容电压特征值中相邻两个特征值相等或相近,和/或不同时刻的第二电容电压特征值中相邻两个特征值相等或相近;当检测不同时刻的第一电容电压特征值中相邻两个电压特征值的差值之差大于预设误差阈值,和/或不同时刻的第二电容电压特征值中相邻两个电压特征值的差值之差大于预设误差阈值时,可以确定当前时刻第一电阻的阻值和/或第二电阻的阻值发生变化,立即对第一电容和第二电容的状态进行切换,从而尽快得到下一切换时刻之后第一电阻的阻值和/或第二电阻的阻值发生变化后对应的电压波形。
在一种可能的设计中,根据继续获取的第一电压波形和第二电压波形,确定第一电阻和第二电阻的阻值,包括:
在确定任意相邻两个电压特征值小于或等于预设误差阈值时,记录第一电容和第二电容在每一切换时刻时第一电压波形和第二电压波形对应的第一电压数值和第二电压数值;以及在确定任意相邻两个电压特征值之差大于预设误差阈值时,删除当前时刻之前记录的第一电压数值以及第二电压数值,并重新记录第一电容和第二电容在后续每一切换时刻时第一电压波形和第二电压波形对应的第一电压数值和第二电压数值;利用记录的述第一电压数值和第二电压数值,确定第一电阻的阻值和第二电阻的阻值。
采用上述方法,由于与第一电阻连接的第一电容和与第二电阻连接的第二电容的放电过程或放电过程中两端的电压满足电容充放电常用关系式,因此可以通过记录的切换时刻第一电压数值和第二电压数值,并利用记录的第一电压数值和第二电压数值,可以准确的计算出第一电阻的阻值和第二电阻的阻值。
在一种可能的设计中,本申请实施例提供的绝缘电阻检测方法还包括:
在确定第一电阻的阻值或第二电阻的阻值小于第一预设绝缘阈值时,向待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。
采用上述方法,可以通过检测的第一电阻的阻值和第二电阻的阻值是否满足待检测装置对绝缘的需求,当第一电阻和第二电阻中任一电阻的阻值不满足绝缘需求时,均断开待检测装置电源和负载的连接,从而保证避免发生触电现象。
在一种可能的设计中,继续获取第一电压波形和第二电压波形之后,本申请实施例提供的绝缘电阻检测方法还包括:
根据继续获取的第一电压波形和第二电压波形,确定第一电阻和第二电阻的并联阻值;
在确定并联阻值小于第二预设绝缘阈值时,向待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。
采用上述方法,第一电阻与第一电容并联,第二电阻与第二电容并联,并串联跨接在待检测装置电源的正极和负极之间,由于待检测装置电源的正极与地之间的电压和负极与地之间的电压较高,当第一电阻和第二电阻中任一电阻发生故障,均会影响待检测装置的安全运行。因此,可以无需计算出第一电阻和第二电阻的准确的阻值,可以通过计算第一电阻和第二电阻的并联阻值也可以确定待检测装置是否发生绝缘故障。
在一种可能的设计中,第一电容电压特征值包括以下一个或多个:第一电容的时间常数和第一电容的电压波形状态;第二电容电压特征值包括以下一个或多个:第二电容的时 间常数和第二电容的电压波形状态;第一电容的波形状态表征第一电容两端电压的波动趋势,第二电容的波形状态表征第二电容两端电压的波形趋势。
第四方面,本申请实施例提供了一种绝缘电阻检测装置,该绝缘电阻检测装置包括:获取模块、处理单元和计算模块。
其中,获取单元可以用于获取第一电容对应的第一电压波形和第二电容对应的第二电压波形,第一电容为待检测电源的正极与地之间的电容,第二电容为电源的负极与地之间的电容。处理单元可以用于控制第一电容和第二电容在第一状态或第二状态之间切换,第一状态为第一电容充电且第二电容放电,第二状态为第一电容放电且第二电容充电。计算单元,用于根据当前时刻已获取的第一电压波形,计算在当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据当前时刻已获取的第二电压波形,计算在当前时刻之前的设定时长内不同时刻的第二电容电压特征值。处理单元还用于根据计算单元输出的不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确定下一切换时刻;以及在到达下一切换时刻时控制第一电容和第二电容进行状态切换。
在一种可能的设计中,获取单元还用于:在到达下一切换时刻时控制第一电容和第二电容进行状态切换之后,继续获取第一电压波形和第二电压波形;处理单元还用于:根据获取单元继续获取的第一电压波形和第二电压波形,确定第一电阻的阻值和第二电阻的阻值。其中,第一电阻为电源的正极与地之间的绝缘电阻,第二电阻为电源的负极与地之间的绝缘电阻,第一电阻的阻值和第二电阻的阻值用于确定是否发生绝缘电阻故障。
在一种可能的设计中,处理单元具体用于:将不同时刻的第一电容电压特征值中任意相邻两个电压特征值进行比较,和/或将不同时刻的第二电容电压特征值中任意相邻两个电压特征值进行比较;在确定任意相邻两个电压特征值之差大于预设误差阈值时,将当前时刻确定为下一切换时刻;以及在确定任意相邻两个电压特征值小于或等于预设误差阈值时,确定第一电容的时长常数和/或第二电容的时间常数,并根据第一电容的时间常数和/或第二电容的时间常数,确定下一切换时刻。
在一种可能的设计中,处理单元具体用于:在确定任意相邻两个电压特征值小于或等于预设误差阈值时,记录第一电容和第二电容在每一切换时刻时第一电压波形和第二电压波形对应的第一电压数值和第二电压数值;以及在确定任意相邻两个电压特征值之差大于预设误差阈值时,删除当前时刻之前记录的第一电压数值以及第二电压数值,并重新记录第一电容和第二电容在后续每一切换时刻时第一电压波形和第二电压波形对应的第一电压数值和第二电压数值;利用记录的述第一电压数值和第二电压数值,确定第一电阻的阻值和第二电阻的阻值。
在一种可能的设计中,处理单元还用于:在确定第一电阻的阻值或第二电阻的阻值小于第一预设绝缘阈值时,向与待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。
在一种可能的设计中,处理单元还用于:根据继续获取的第一电压波形和第二电压波形,确定第一电阻和第二电阻的并联阻值,确定第一电阻和第二电阻的并联阻值;在确定并联阻值小于第二预设绝缘阈值时,向与待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。
在一种可能的设计中,第一电容电压特征值包括以下一个或多个:第一电容的时间常数和第一电容的电压波形状态;第二电容电压特征值包括以下一个或多个:第二电容的时 间常数和第二电容的电压波形状态;第一电容的波形状态表征第一电容两端电压的波动趋势,第二电容的波形状态表征第二电容两端电压的波形趋势。
第五方面,本申请实施例中还提供一种计算机可读存储介质,计算机可读存储介质中存储有计算机可读指令,当计算机可读指令在计算机上运行时,使得如第三方面或第三方面中任一种可能的设计中的方法被执行。
附图说明
图1本申请绝缘电阻检测装置应用场景的结构示意图;
图2为本申请实施例中一种绝缘电阻检测电路的结构示意图;
图3为本申请实施例中一种状态控制单元的电路结构示意图一;
图4为本申请实施例中一种绝缘电阻检测电路的电路结构示意图一;
图5为本申请实施例中一种第一电压和第二电压变化曲线示意图一;
图6为本申请实施例中一种第一电压和第二电压变化曲线示意图二;
图7为本申请实施例中一种第一电压和第二电压变化曲线示意图三;
图8为本申请实施例中一种绝缘电阻检测电路的电路结构示意图二;
图9为本申请实施例中一种高压系统监控装置的结构示意图;
图10为本申请实施例中一种绝缘电阻检测方法的流程示意图;
图11为本申请实施例中一种绝缘电阻检测方法的示意流程图;
图12为本申请实施例中绝缘电阻检测装置的结构示意图。
具体实施方式
本申请实施例提供一种绝缘电阻检测电路、方法、装置及其存储介质。其中,方法和装置是基于相同或相似技术构思的,由于方法及装置解决问题的原理相似,因此装置与方法的实施可以相互参见,重复之处不再赘述。
需要说明的是,本申请实施例的描述中,“和/或”,描述关联对象的关联关系,表示可以存在三种关系,例如,A和/或B,可以表示:单独存在A,同时存在A和B,单独存在B这三种情况。“连接”,描述两个对象的连接关系,可以表示两种连接关系,例如,A和B连接,可以表示:A与B直接连接,A通过C和B连接这两种情况。字符“/”一般表示前后关联对象是一种“或”的关系。本申请中所涉及的至少一个是指一个或多个;多个,是指两个或两个以上。另外,需要理解的是,在本申请的描述中,“第一”、“第二”、“第三”等词汇,仅用于区分描述的目的,而不能理解为指示或暗示相对重要性,也不能理解为指示或暗示顺序。在本说明书中描述的参考“一个实施例”或“一些实施例”等意味着在本申请的一个或多个实施例中包括结合该实施例描述的特定特征、结构或特点。由此,在本说明书中的不同之处出现的语句“在一个实施例中”、“在一些实施例中”、“在其他一些实施例中”、“在另外一些实施例中”等不是必然都参考相同的实施例,而是意味着“一个或多个但不是所有的实施例”,除非是以其他方式另外特别强调。术语“包括”、“包含”、“具有”及它们的变形都意味着“包括但不限于”,除非是以其他方式另外特别强调。本申请实施例公式中乘法可以用“*”表示,也可以用“×”表示。并联可以用“||”表示。
本申请实施例提供的基于绝缘电阻检测电路、方法、装置及其存储介质可应用于电动 汽车、数控机床、风力发电系统、光伏发电系统以及其它采用高压供电的装置中,用于检测待检测装置中的电源的正极和负极之间的绝缘电阻是否失效。
下面将结合附图,对本申请实施例进行详细描述。
图1示例性示出一种电动汽车的应用场景。如图1所示,电动汽车中至少包括:电源模块、高压上下电模块和高压负载。其中,电源模块中包括多个电池组用于为高压负载供电,高压上下电模块用于控制电源模块与高压负载的连接。本申请实施例提供的绝缘电阻检测电路可以连接在电源模块的电源的正极输出端HVDC+和负极输出端HVDC-之间,用于检测电源模块的正极和负极之间的绝缘电阻是否失效。
参见图2所示,为本申请提供的一种绝缘电阻检测电路的结构示意图,该绝缘电阻检测电路200可以与待检测装置电源的正和电源的负极连接,用于快速准确的检测出待检测电源的正极与地之间的绝缘电阻的阻值以及电源的负极与地之间的绝缘电阻的阻值,并根据检测的绝缘电阻的阻值确定待检测装置电源的正极和电源的负极之间是否发生绝缘故障。
具体地,绝缘电阻检测电路200可以包括:状态控制单元201、第一分压支路202、第二分压支路203和处理器204。
其中,状态控制单元201跨接在待检测装置的电源的正极HVDC+和电源的负极HVDC-之间。处理器204分别与状态控制单元201、第一分压支路202和第二分压支路203连接。
其中,状态控制单元201在处理器204的控制下在第一状态或第二状态之间切换。状态控制单元204处于第一状态时第一电容C1充电且第二电容放电C2,状态控制单元201处于第二状态时第一电容C1放电且第二电容C2充电,第一电容C1为电源的正极与地之间的电容,第二电容C2为电源的负极与地之间的电容。第一分压支路202用于与第一电容C1并联,并用于对第一电容C1两端的电压进行分压,得到第一电压波形。第二分压支路203用于与第二电容C2并联,并对第二电容C2两端的电压进行分压,得到第二电压波形。处理器204用于:根据当前时刻已得到的第一电压波形,计算当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据当前时刻已得到的第二电压波形,计算当前时刻之前的设定时长内不同时刻的第二电容电压特征值;并根据不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确定下一切换时刻,并在到达下一切换时刻时控制状态控制单元201进行状态切换。
进一步的,处理器204根据在到达下一切换时刻时控制状态控制单元201进行状态切换之后,并利用后续状态控制单元201在第一状态和第二状态时,第一分压支路202已得到的第一电压波形和第二分压支路203已得到的第二电压波形,确定第一电阻R1的阻值和第二电阻R2的阻值。其中,第一电阻R1为电源的正极与地之间的绝缘电阻,第二电阻R2为电源的负极与地之间的绝缘电阻,第一电阻R1和阻值和第二电阻R2的阻值用于确定待检测装置是否发生绝缘电阻失效,以及是否出现绝缘故障。
应理解,第一电容C1与第一分压支路202并联,因此,可以通过检测第一分压支路202上的第一电压波形确定第一电容C1两端的电压变化情况。同理,可以通过检测第二分压支路203的第二电压波形确定第二电容C2两端的电压变化情况。
实际使用时,状态控制单元201控制第一电容C1和第二电容C2的充电过程和放电过程,若第一电阻R1的阻值和第二电阻R2的阻值维持不变,则得到的第一电压波形和得到的第二电压波形以固定规律变化,不同时刻得到的第一电容电压特征值和/或不同时刻得到的第二 电容电压特征值相等或相近。若在第一电容和第二电容充电过程和放电过程中,若第一电阻R1的阻值和第二电阻R2的阻值发生变化,则在第一电阻R1的阻值和第二电阻R2的阻值发生变化的时刻,第一电压波形和第二电压波形的变化规律发生改变,因此,可以通过检测与表征第一电压波形变化规律的第一电容电压特征值和/或表征第二电压波形变化的第二电容的电压特征值,确定当前第一电阻R1的阻值和第二电阻R2的阻值是否发生变化,以及根据第一电阻R1的阻值和第二电阻R2的阻值的变化情况调整状态控制单元201的状态切换时刻,尽快得到当前第一电阻R1的阻值和第二电阻R2的阻值对应的第一电压波形和第二电压波形,从而准确计算的第一电阻R1的阻值和第二电阻R2的阻值,并确定待检测装置是否发生绝缘故障。
应理解,由于第一电容C1和第二电容C2串联连接在电源的正极HVDC+负极HVDC-之间,当与第一电容C1并联的第一电阻R1发生变化时,第一电容C1两端的电压发生变化,而电源的正极HVDC+负极HVDC-之间的电压数值保持不变,因此,第二电容C2两端的电压也会相应发生变化,因此,可以检测不同时刻的第一电容C1电压特征值或者不同时刻的第二电容C2电压特征值即可确定第一电阻R1的阻值和第二电阻R2的阻值是否发生变化。
在另一示例中,由于检测误差等原因,检测的不同时刻的第一电容C1电压特征值之间允许有一定误差,为了避免检测失误,可以通过同时检测不同时刻的第一电容C1电压特征值和不同时刻的第二电容C2电压特征值,准确的判断出第一电阻R1的阻值和第二电阻R2的阻值是否发生变化,从而准确的确定下一切换时刻。其中,第一电容C1电压特征值可以是但不限于第一电容的时间常数和/或第一电容的电压波形状态。第二电容电压特征值可以是但不限于第二电容的时间常数和/或第二电容的电压波形状态。其中,第一电容的波形状态表征第一电容两端电压的波动趋势,第二电容的波形状态表征第二电容两端的波形趋势。
进一步的,第一电压波形的方向和第二电压波形的方向相同,其中,第一电压波形和第二电压波形的方向相同,其具体含义可以是:第一分压支路202输出第一电压波形时,输出高电位的一端与处理器204接收高电位的一端连接,输出低电位的第一端与处理器204接收低电位的一端连接,高低电位之差等于第一电压;第二分压支路203输出第二电压波形时,输出高电位的一端与处理器204接收高电位的一端连接,输出低电位的一端与处理器204接收低电位的一端连接,高低电位之差为第二电压。
本申请中,可以通过处理器204实现状态控制单元201在第一状态和第二状态之间切换。
具体地,处理器204可以向状态控制单元201发送控制信号,以控制状态控制单元201处于第一状态或者第二状态。其中,第一状态可以是但不限于:第一电容C1充电且第二电容C2放电。第二状态可以是但不限于:第一电容C1放电且第二电容C2充电。
实际应用中,待检测装置上可以设置有固定接口,绝缘电阻检测电路200可以通过固定接口与待检测装置连接,从而实现检测第一电阻R1的阻值和第二电阻R2的阻值。
具体实现时,处理器204可以与状态控制单元201连接,并向状态控制单元201发送控制信号,状态控制单元201接收到该控制信号后,响应于该控制信号控制状态控制单元201在第一状态和第二状态之间切换。
具体实现时,处理器204可以是微控制单元(micro controller unit,MCU)、中央处理器(central processing unit,CPU)、数字信号处理器(digital singnal processor,DSP)中的任一种。当然,处理器的具体形态不限于上述举例。
下面,对绝缘检测电路200中的状态控制单元201、第一分压支路202、第二分压支路203以及处理器204的具体结构进行介绍。
一、状态控制单元201
状态控制单元201跨接在待检测装置的电源的正极和负极之间,状态控制单元201可以用于在处理器204的控制下在第一状态或第二状态之间切换。其中,状态控制单元201处于第一状态时第一电容C1充电且第二电容C2放电,状态控制单元201处于第二状态时第一电容C1放电且第二电容C2充电,第一电容C1为电源的正极与地之间的电容,第二电容C2为电源的负极与地之间的电容。
其中,状态控制单元201可以包括第一开关单元和第二开关单元。
具体地,第一开关单元的第一端与电源的正极连接,第一开关单元的第二端与地连接。第二开关单元的第二端与电源的负极连接,第二开关单元的第二端与地连接。其中,第一开关单元闭合且第二开关单元断开时,状态控制单元201处于第一状态。第一开关单元断开且第二开关单元闭合时,状态控制单元201处于第二状态。
其中,设置第一开关单元的作用是:通过第一开关单元的闭合和断开控制与第一开关单元并联的第一电容放电和充电,设置第二开关单元的作用是:通过第二开关单元的闭合和断开控制与第二开关单元并联的第二电容放电和充电。
具体地,第一开关单元可以包括第一开关和第三电阻。第二开关单元可以包括第二开关和第四电阻。
其中,设置第一开关的作用为:通过改变第一开关的状态控制第一电容充电或放电。设置第三电阻的作用为:为第一电容提供放电路径以及避免当第一开关闭合时电源正极与地之间短路。设置第二开关的作用为:通过改变第二开关的状态控制第二电容充电或放电。设置第四电阻的作用为:为第二电容提供放电路径时避免当第二开关闭合时电源负极与地之间短路。
具体地,第三电阻的第一端与电源的正极连接,第三电阻的第二端与第一开关的第一端连接;第一开关的第二端与地连接;第二开关的第一端与地连接,第二开关的第二端与第四电阻的第一端连接;第四电阻的第二端与电源的负极连接。
具体地,第一开关和第二开关可以是开关管,若第一开关和第二开关为金属氧化物半导体(metal oxide semiconductor,MOS)管,MOS管的栅极可以为第一开关和第二开关单元的控制端与处理器204连接,处理器204通过控制MOS管的通断实现控制状态控制单元201在第一状态和第二状态之间切换;若第一开关和第二开关为双极结型晶体管(bipolar junction transistor,BJT),BJT的基极可以为第一开关和第二开关的控制端与处理器204连接,处理器204可以通过控制BJT的通断实现控制状态控制单元201在第一状态和第二状态之间切换。
为了便于理解,下面给出状态切换单元201的具体示例。
参见图3所示,为本申请实施例中状态控制单元201的结构示意图。在图3所示的电路中,包括开关K1和K2,电阻R3和R4。其中,A和B作为状态切换单元201的输入端,分别与待检测装置的电源的正极HVDC+和负极HVDC-连接,C和D作为状态控制单元201的控制端,均与处理器204连接,E和F作为状态控制单元201的输出端,分别与第一分压支路202和第二分压支路203连接。
图3所示的状态控制单元201中,各器件的连接关系可以是:R3的第一端与待检测装置的电源正极HVDC+连接,R3的第二端与K1的第一端连接,K1的控制端与处理器204连接,K1的第二端分别与K2的第二端和地线连接,K2的控制端与处理器204连接,K2的第二端与R4的第一端连接,R4的第二端与待检测装置的电源的负极HVDC-连接。
采用图3所示的状态控制单元201控制第一电容C1和第二电容C2充电和放电时,以第一电容C1为例,当K1断开时,C1两端的电阻为第一电阻R1和第一分压支路202上的电阻,HVDC+通过第一电阻R1和第一分压支路202为第一电容C1充电,直至第一电容C1两端的电压充电至稳态数值,当K1闭合时,第一电容C1为R3提供电流,此时第一电容C1通过R3和第一分压支路、以及第一电阻R1放电。同理,可以通过控制开关K2控制第二电容C2充电或放电。
当然,以上对状态控制单元201结构的介绍仅为示例,实际应用中,状态控制单元201也可以采用其它结构,例如状态控制单元201可以采用继电器,通过改变继电器的输入量实现状态控制单元201处于第一状态和第二状态。
二、第一分压支路202
第一分压支路202用于与第一电容C1并联连接,第一分压支路202可以用于对第一电容C1两端的电压进行分压,得到第一电压波形。
应理解,由于本申请实施例提供的绝缘检测电路200与待检测装置的电源的正极和负极连接,而电源的正极和负极之间的电压较高,因此,直接获取的第一电容C1两端的电压可能难以满足处理器204对电压的需求,因此,可以通过获取与第一电容C1并联的第一分压支路202上的电压,实现输出满足处理器204电压要求的表征第一电容C1两端电压变化的第一电压波形。
具体地,第一分压支路202可以包括:第五电阻和第六电阻。
其中,第五电阻的一端与电源的正极连接,第五电阻的第二端分别与第六电阻的第一端和处理器204连接;第六电阻的第二端与地和处理器204连接。其中,第六电阻的阻值远远小于第五电阻的阻值。
其中,设置第五电阻和第六电阻的作用为:由于第一分压支路202与第一电容C1并联,因此,可以通过第五电阻和第六电阻对第一电容C1两端的电压进行分压,并通过检测第六电阻两端的电压波形,得到第一电容C1充电过程和放电过程的电压波形,从而无需采用检测成本更高的高压检测器件得到第一电容C1两端的电压。
应理解,为了实现检测到第一电压波形中相邻两个数值之间的微小电压变化,提高检测结果的准确度,第六电阻的阻值远远小于第五电阻的阻值。其中,第五电阻和第六电阻的阻值可以根据绝缘电阻检测电路200的应用场景以及处理器204的规格进行设置,本申请这里不做详细介绍。
当然,以上对第一分压支路202结构的介绍仅为示例,实际应用中,第一分压支路202也可以采用其它结构,例如第一分压支路202中可以设置采用两个以上电阻串联连接的结构。
三、第二分压支路203
第二分压支路203用于与第二电容C2并联,第二分压支路203可以用于对第二电容C2两端的电压进行分压,得到第二电压波形。
应理解,由于本申请实施例提供的绝缘检测电路200与待检测装置的电源的正极和负极连接,而电源的正极和负极之间的电压较高,因此,直接获取的第二电容C2两端的电压可能难以满足处理器204对电压的需求,因此,可以通过获取与第二电容C2并联的第二分压支路203上的电压,实现输出满足处理器204电压要求的表征第二电容C2两端电压变化的第二电压波形。
具体地,第二分压支路203可以包括:第七电阻和第八电阻。
其中,第七电阻的第一端与地和处理器204连接,第七电阻的第二端分别与第八电阻的第一端和处理器204连接;第八电阻的第二端与电源的负极连接。其中,第七电阻的阻值远远小于第五电阻的阻值。
其中,设置第七电阻和第八电阻的作用为:由于第二分压支路203与第一电容并联,因此,可以通过第七电阻和第八电阻对第二电容C2两端的电压进行分压,并通过检测第七电阻两端的电压波形,得到第二电容C2充电过程和放电过程的电压波形,从而无需采用检测成本更高的高压检测器件得到第二电容C2两端的电压。
应理解,为了实现检测到第二电压波形中相邻两个数值之间的微小电压变化,提高检测结果的准确度,第七电阻的阻值远远小于第八电阻的阻值。其中,第七电阻和第八电阻的阻值可以根据绝缘电阻检测电路200的应用场景以及处理器204的规格进行设置,本申请这里不做详细介绍。
当然,以上对第二分压支路203结构的介绍仅为示例,实际应用中,第二分压支路203也可以采用其它结构,例如第二分压支路203中可以设置采用两个以上电阻串联连接的结构。
四、处理器204
处理器204分别与状态控制单元201、第一分压支路202第二分压支路203连接,处理器204可以用于根据当前时刻已得到的第一电压波形,计算当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据当前时刻已得到的第二电压波形,计算当前时刻之前的设定时长内不同时刻的第二电容电压特征值;并根据不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确定状态控制单元201的下一切换时刻,并在到达下一切换时刻时控制状态控制单元201进行状态切换。处理器204还可以用于在到达下一切换时刻时控制状态控制单元201进行状态切换之后,在第一状态和第二状态已得到的第一电压波形和第二电压波形,确定第一电阻R1的阻值和第二电阻R2的阻值。其中,第一电阻R1为电源的正极与地之间的绝缘电阻,第二电阻R2为电源的负极与地之间的绝缘电阻,第一电阻R1的阻值和第二电阻R2的阻值用于确定待检测装置是否发生绝缘电阻故障。
其中,第一电容电压特征值可以是但不限于:第一电容的时间常数和/或第一电容的电压波形状态。第二电容电压特征值可以是但不限于:第二电容的时间常数和/或第二电容的电压波形状态。其中,第一电容的波形状态表征第一电容两端电压的波动趋势,第二电容的波形状态表征第二电容两端电压的波形趋势。
示例的,若第一电容电压特征值为电压波形状态,当第一电压波形中任意相邻两个电压数值之间,在后的第二数值大于在前的第一数值预设阈值时,可以确定第二数值对应时刻的第一电容两端电压的波形趋势为上升,可以确定第二数值对应时刻的第一电容电压特征值为1。若在后的第二数值小于在前的第一数值时,可以确定第二数值对应时刻的第一 电容两端电压的波形趋势为下降,可以确第二数值对应时刻的第一电容电压特征值0。其中,预设阈值可以根据绝缘电阻检测电路200的应用场景进行设置,本申请这里不做详细介绍。
具体地,当确定不同时刻的第一电容电压特征值中任意相邻两个电压特征值进行比较,和/或将不同时刻的第二电容电压特征值中任意相邻两个电压特征值的之差大于预设误差阈值时,若任意相邻两个电压特征值之差大于预设误差阈值,可以确定该时刻第一电阻的阻值R1和/或第二电阻R2的阻值发生变化,可以将当前时刻确定为下一切换时刻,从而尽快得到第一电阻R1的阻值和/或第二电阻R2的阻值发生变化后的第一电压波形和第二电压波形,并利用重新获取的第一电压波形和第二电压波形,准确的检测出待检测装置当前是否发生绝缘故障。
具体地,当确定不同时刻的第一电容电压特征值中任意相邻两个电压特征值之差小于或等于预设误差阈值,和/或不同时刻的第二电容电压特征值中任意相邻两个电压特征值之差小于或等于预设误差阈值时,可以确定该时刻第一电阻R1的阻值和第二电阻R2的阻值不变,确定第一电容的时间常数和第二电容的时间常数,并根据第一电容的时间常数和/或第二电容的时间常数,计算出状态控制单元201的正确切换时间,并利用切换后得到的第一电压波形和第二电压波形准确的计算出当前第一电阻R1的阻值和第二电阻R2的阻值。其中,当第一电容电压特征值为电压波形状态,可以将预设误差阈值设置为1。其中,当第一电容电压特征值为时间常数时,第一电容的时间常数可以为不同时刻的第一电容电压特征值的平均值,预设误差阈值可以根据绝缘电阻检测电路200的应用场景以及该应用场景对检测结果的准确的要求设置,本申请这里不做详细介绍。
应理解,为了快速计算出第一电阻R1的阻值和第二电阻R2的阻值,可以本申请实施例提供的绝缘电阻检测电路200还可以包括第九电阻和第三开关。
具体地,第三开关的第二端与地连接,第三开关的控制端与处理器204连接。
处理器204还可以还用于:控制第三开关闭合和断开;以及根据在到达下一切换时刻之后在第一状态和第二状态时第一分压支路201已得到的第一电压波形、第二分压支路202已得到的第二电压波形以及第三开关闭合时第九电阻两端的电压波形,计算第一电阻和第二电阻的并联阻值。其中,该并联阻值可以用于确定待检测装置是否发生绝缘电阻故障。
应理解,由于需要实时或者周期性的得到第一电压波形和第二电压波形,并利用一时长内得到的第一电压波形和第二电压波形才能计算第一电阻的阻值和第二电阻的阻值,或第一电阻和第二电阻的并联阻值,因此,绝缘电阻检测电路200还可以包括用于存储第一电压波形和第二电压波形的存储器。
结合以上描述,示例地,如图4所示,为本申请实施例提供的一种绝缘电阻检测电路的电路结构图。
其中,该绝缘电阻检测电路,可以包括状态控制单元、第一分压支路、第二分压支路和处理器。
在状态控制单元中,包括开关K1和K2以及电阻R3和R4。其中,R3的第一端与待检测装置电源的正极HVDC+连接,R3的第二端与K1的第一端连接,K2的第二端与地连接,K2的第一端与地连接,K2的第二端与R4的第一端连接,R4的第二端与待检测装置的电源的负极HVDC-连接,K1和K2的控制端均与处理器连接。
在第一分压支路中,包括第五电阻R5和第六电阻R6。其中,R5的一端与电源的正极连接,R5的第二端分别与R6的第一端和处理器连接,R6的第二端与地和处理器连接。其中,R6两端输出第一电压波形。
在第二分压支路中,包括第七电阻R7和第八电阻R8。其中,R7的第一端与地和处理器连接,R7的第二端分别与R8的第一端和处理器连接,R8的第二端与电源的负极连接。其中,R7两端输出第二电压波形。
在处理器中,处理器分别与R6两端、R7两端、K1的控制端、K2的控制端以及存储器连接。
采用图4所示的绝缘电阻检测电路检测第一电阻和第二电阻时,A和B作为单相输入端,分别于待检测装置的电源的正极HVDC+和电源的负极HVDC-连接,能量从左向右传输。其中,C1为待检测装置电源的正极与地之间的安规电容,C2为待检测装置电源的负极与地之间的安规电容,R1为待检测装置电源的正极与地之间的绝缘电阻,R2为待检测装置电源的负极与地之间的绝缘电阻。
下面结合图4,对本申请实施例提供的绝缘电阻检测电路的工作原理进行说明。
下面以K1闭合且K2断开为开关状态一,K1断开且K2闭合为开关状态二为例进行说明。K1和K2在处理器的控制下,在开关状态一和开关状态二之间切换。
处理器向K1和K2发送第一控制信号,K1和K2响应第一控制信号处于开关状态一,此时第一电容C1通过R1、R5、R6和R3放电,第二电容C2通过R2、R7和R8充电,处理器通过与R6连接的端口得到第一电压波形以及与R7连接的端口得到第二电压波形。处理器根据当前时刻已得到的第一电压波形计算当前时刻之前的设定时长内不同时刻的第一电容电压特征值,和/或根据当前时刻之前已得到的第二电压波形计算当前时刻之前的设定时长内不同时刻的第二电容电压特征值,确定下一切换时刻。若不同时刻的第一电容电压特征值中任意相邻两个电压特征值的之差小于或等于预设误差阈,和/或不同时刻的第二电容电压特征值中任意相邻两个电压特征值的之差小于或等于预设误差阈值时,可以确定当前时刻之前第一电阻的阻值和第二电阻的阻值并未发生变化,可以利用根据当前时刻已得到的第一电压波形计算的第一电容的时间常数和/或根据当前时刻已得到的第二电压波形计算的第二电容的时间常数,确定下一切换时刻,并在到达下一切换时刻时,向K1和K2发送第二控制信号,控制K1和K2由开关状态一切换为开关状态二。若不同时刻的第一电容电压特征值中任意相邻两个电压特征值的之差大于预设误差阈值,和/或不同时刻的第二电容电压特征值中相邻两个电压特征值的之差大于预设误差阈值时,可以确定当前时刻之前第一电阻的阻值和第二电阻的阻值发生变化,可以将当前时刻确定为下一切换时刻,向K1和K2发送第二控制信号,控制K1和K2由开关状态一切换为开关状态二。其中,第一电阻R1为电源的正极与地之间的绝缘电阻,第二电阻R2为电源的负极与地之间的绝缘电阻,第一电阻R1的阻值和第二电阻R2的阻值用于确定待检测装置是否发生绝缘电阻故障。
需要说明的是,第一电容C1和第二电容C2串联连接在待检测电源的正极HVDC+和电源的负极HVDC-之间,当与第一电容C1并联的第一电阻R1的阻值发生变化时,第一电容C1两端的电压发生变化,而电源的正极HVDC+和电源的负极HVDC-之间的电压数值保持不变,第二电容C2两端的电压也会相应发生变化,因此,可以检测不同时刻第一电容电压特征值或者不同时刻第二电容电压特征值即可确定第一电阻的阻值和第二电阻 的阻值是否发生变化。
示例的,由于已得到的第一电压波形计算不同时刻的第一电容电压特征值时,若第一电阻R1阻值变化数值较少,造成计算出来的不同时刻的第一电容电压特征值中,第一电阻R1阻值对应的时刻的电压特征值与任意相邻时刻计算的电压特征值差值较少,造成检测误差,可以同时计算不同时刻的第一电容电压特征值和不同时刻的第二电容电压特征值,来实现准确的判断当前时刻之前第一电阻R1的阻值和第二电阻R2的阻值是否发生变化。
示例的,若第一电容电压特征值为第一电容的时间常数,当确定当前时刻之前第一电阻的阻值和第二电阻的阻值未发生变化,可以将计算的不同时刻第一电容电压特征值的平均值作为第一电容的时间常数,并计算下一切换时刻。其中,下一切换时刻可以是K1和K2切换为开关状态一经过预设时长时对应的时刻。其中,预设时长为3到5个时长常数。
处理器在确定下一切换时刻之后,利用上述切换时刻的确定方式K1和K2闭合和断开,并在K1和K2处于开关状态一和开关状态二时得到第一电压波形和得到第二电压波形,确定第一电阻R1的阻值和第二电阻R2的阻值。
具体地,在确定第一电阻R1的阻值和第二电阻R2的阻值发生变化时,可以将当前时刻确定下一切换时刻,尽快得到下一切换时刻第一电阻R1和第二电阻R2阻值发生变化时对应的第一电压波形和第二电压波形,并利用得到的第一电压波形和第二电压波形计算出第一电阻R1的阻值和第二电阻R2的阻值,以及根据第一电阻R1的阻值和第二电阻R2确定待检测装置是否发生故障。
示例的,在确定第一电阻R1的阻值或第二电阻R2的阻值小于第一预设绝缘阈值时,确定第一电阻R1的阻值和第二电阻R2的阻值无法满足待检测装置对绝缘电阻的需求,向与待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接,从而保证待检测的运行安全。
下面,结合图4,以第一电容电压特征值和第二电容电压特征值为时间常数为例,对根据当前时刻已得到的第一电压波形,计算当前时刻之前的设定时长内不同时刻的第一电容电压特征值的具体过程进行详细说明。
需要说明的是,R5和R6串联后与第一电容C1并联,R7和R9串联后与第二电容C2并联,因此,R6两端的第一电压波形中第一时刻对应的数值与第一电容C1两端的电压波形中第一时刻对应的数值呈现比值关系,R7两端的第二电压波形中第一时刻对应的数值与第一电容C2两端的电压波形中第一时刻对应的数值呈现比值关系。因此,为了便于理解,下面以第一电容C1和第二电容C2两端的电压波形为例,对不同时刻的第一电容的电压特征值的计算过程进行详细说明。
处理器向K1和K2的控制端发送第一控制信号,K1和K2响应与第一控制信号处于开关状态一,此时第一电容C1通过R1、R5、R6和R3放电,第二电容C2通过R2、R7和R8充电。此时,第一电压C1两端的电压U1和第二电压C2两端的电压U2满足电容充放电常用关系式:
U1(t)=U1_st-(U1st-V0)*e^(-t/τ1);U2(t)=U2_st-(U2st-V2)*e^(-t/τ2)。
其中,V0和V2分别为K1和K2切换为开关状态一时的第一电压值和第二电压值,U1st和U2st分别为K1和K2切换为第二状态时,第一电容两端的数值和第二电容两端的数值。τ1和τ2分别为第一电容C1的时间常数和第二电容C2的时间常数。t为第一电容C1和第二电容C2切换为第一状态后的对应时刻。其中,第一电容C1通过R1、R5、R6 和R3放电,第二电容C2通过R2、R7和R8放电,因此,τ1=C1*(R1||R3||R5+R6),τ2=C2*(R2||R7+R8)。其中,C1为第一电容C1的容值,C2为第一电容C2的容值。
具体地,若在当前时刻之前第一电阻R1的阻值和第二电阻R2的阻值并未发生变化,如图5所示,则当前时刻之前第一电压波形和当前时刻已得到的第二电压波形以固定规律变化。其中,U1’(t)为第一电容C1在K1和K2处于第二状态时对应的电压波形,U2’(t)为第二电容C2在K1和K2处于第二状态时对应的电压波形。
当第一电阻R1的阻值和第二电阻R2的阻值发生变化,如图6或图7所示,在第一电阻R1的阻值和第二电阻R2的阻值发生变化之前,第一电压波形和第二电压波形以第一规律变化,第一电阻R1的阻值和第二电阻R2的阻值的发生变化之后,第一电压波形和第二电压波形以第二规律变化。其中,绝缘状态突变是指第一电阻R1的阻值和第二电阻R2的阻值发生变化。
其中,确定第一电阻R1的阻值和第二电阻R2的阻值是否发生变化,需要先计算出不同时刻第一电容电压特征值和/或第二电容电压特征值,下面结合上述公式,以第一电容的电压特征值为时间常数为例,对第一电容电压特征值的确定过程进行详细说明。
对上述公式中第一电容两端的电压对应的充放电常用公式进行求导(derivation)可以得到下述公式:
Figure PCTCN2020099031-appb-000001
对上述求导后的公式取对数(logarithm),可以得到下述公式:
Figure PCTCN2020099031-appb-000002
Figure PCTCN2020099031-appb-000003
此时,取对数之后的第一电容两端的第一电压的上述公式满足线性公式Y=a+b·X的线性公式。
其中,
Figure PCTCN2020099031-appb-000004
其中,X为K1切换为开关状态一以后对应的采集时刻。X(i)表示采集第i个点的时刻,X(i-1)表示采集第i-1个点的时刻,M为设置的采集点,Y为第一电容电压值。可以看出,当K1切换为开关状态一时M=0且Y=0。其中,对采集的点数进行累加,则进行以下计算:
M=M+1
Figure PCTCN2020099031-appb-000005
实时更新采集点M,并通过新的采集点M、采集时刻X(i),对采集点M和采集时刻X(i)进行累加,更新上述公式中的数值,得到下述公式:
X=X+X(i)
XX=XX+X(i) 2
Y=Y+Y(i)
XY=XY+X(i)*Y(i)
当采集的点数M达到M≥N点后,通过以下公式计算得到线性公式中的b值。N为自然数。
Figure PCTCN2020099031-appb-000006
因为
Figure PCTCN2020099031-appb-000007
因此可以计算得到时间常数
Figure PCTCN2020099031-appb-000008
其中,设定的采集点数可以通过当前时刻之前已得到的第一电压波形中得到。
同理,可以利用当前时刻之前已经得到的第二电压波形可以计算得到第二电容的时间常数τ2。
采用上述方式计算当前时刻之前的设定时长内不同时刻的第一电容电压特征值,以及计算当前时刻之前的设定时长内不同时刻的第二电容电压特征值。
需要说明的是,根据前述实施例提供的第一分压支路、第二分压支路、以及状态控制单元结构的不同,本申请实施例提供的绝缘电阻检测电路还具有其它几种结构,其它电路结构原理相同,本申请不一一详细介绍。
结合以上描述,示例地,如图8所示,为本申请实施例提供的另一种绝缘电阻检测电路的电路结构图。
其中,该绝缘电阻检测电路,可以包括状态控制单元、第一分压支路、第二分压支路、处理器、第九电阻R9和第三开关K3。
在状态控制单元中,包括开关K1和K2以及电阻R3和R4。其中,R3的第一端与待检测装置电源的正极HVDC+连接,R3的第二端与K1的第一端连接,K2的第二端与地连接,K2的第一端与地连接,K2的第二端与R4的第一端连接,R4的第二端与待检测装置的电源的负极HVDC-连接,K1和K2的控制端均与处理器连接。
在第一分压支路中,包括第五电阻R5和第六电阻R6。其中,R5的一端与电源的正极连接,R5的第二端分别与R6的第一端和处理器连接,R6的第二端与地和处理器连接。其中,R6两端输出第一电压波形。
在第二分压支路中,包括第七电阻R7和第八电阻R8。其中,R7的第一端与地和处理器连接,R7的第二端分别与R8的第一端和处理器连接,R8的第二端与电源的负极连接。其中,R7两端输出第二电压波形。
在处理器中,处理器分别与R6两端、R7两端、K1的控制端、K2的控制端、R9两端、K3的控制端以及存储器连接。
R9的第一端分别与电源的正极和处理器连接,R9的第二端分别与K3的第一端和处理器连接,K3的第二端与地连接,K3的控制端与处理器连接。其中,R3的阻值小于预设阈值。
采用图8所示的绝缘电阻检测电路检测第一电阻和第二电阻时,A和B作为单相输入端,分别于待检测装置的电源的正极HVDC+和电源的负极HVDC-连接,能量从左向右传输。其中,C1为待检测装置电源的正极与地之间的安规电容,C2为待检测装置电源的负极与地之间的安规电容,R1为待检测装置电源的正极与地之间的绝缘电阻,R2为待检测装置电源的负极与地之间的绝缘电阻。
下面结合图8,对本申请实施例提供的绝缘电阻检测电路的工作原理进行说明。
下面以K1闭合且K2断开为开关状态一,K1断开且K2闭合为开关状态二为例进行说明。其中,K1和K2处于开关状态一时C1放电且C2充电,K1和K2处于开关状态二时C1充电且C2放电。
处理器向K3发送第一控制信号,K3响应于第一控制信号闭合,向K1和K2发送第二控制信号,K1和K2响应第二控制信号,K1和K2处于开关状态一,此时第一电容C1通过R1、R5、R6、R9和R3放电,第二电容C2通过R2、R7和R8充电,处理器通过与R6和R7连接的端口,得到第一电压波形和第二电压波形。处理器根据当前时刻已得到的第一电压波形计算当前时刻之前的设定时长内不同时刻的第一电容电压特征值,和/或根据当前时刻之前已得到的第二电压波形计算当前时刻之前的设定时长内不同时刻的第二电容电压特征值,确定一下切换时刻。若不同时刻的第一电容电压特征值中任意相邻两个电压特征值的之差小于或等于预设误差阈值,和/或不同时刻的第二电容电压特征值中任意相邻两个电压特征值的之差小于或等于预设误差阈值时,可以确定当前时刻之前第一电阻的阻值和第二电阻的阻值并未发生变化,可以利用根据当前时刻已得到的第一电压波形计算的第一电容的时间常数和/或根据当前时刻已得到的第二电压波形计算的第二电容的时间常数,确定下一切换时刻。若不同时刻的第一电容电压特征值中任意相邻两个电压特征值的之差大于预设误差阈值,和/或不同时刻的第二电容电压特征值中任意相邻两个电压特征值的之差大于预设误差阈值时,可以确定当前时刻之前第一电阻的阻值和第二电阻的阻值发生变化,可以将当前时刻确定为下一切换时刻。
示例的,若第一电容电压特征值为第一电容的时间常数,可以将计算的不同时刻第一电容电压特征值的平均值作为第一电容的时间常数,计算下一切换时刻。
处理器在确定到达下一切换时刻时,可以K3发送第二控制信号,K3响应第二控制信号闭合,并检测R9两端的电压波形,并利用R9两端的电压波形,确定第一电阻和第二电阻的并联阻值。其中,第一电阻为电源的正极与地之间的绝缘电阻,第二电阻为电源的负极与地之间的绝缘电阻,第一电阻和第二电阻的并联阻值可以用于确定是否发生绝缘电阻故障。
应理解,由于第一电阻R1和第二电阻R2中任一电阻发生故障,均会造成待检测装置绝缘失效,出现漏电现象,因为,可以通过控制K3断开和闭合,通过第三闭合时,R9两端的电压波形,计算出第一电阻和第二电阻的并联阻值,并通过该并联阻值确定待检测装置的绝缘情况。
示例的,在确定第一电阻R1和第二电阻R2的并联阻值小于第二预设绝缘电阻阈值时,确定第一电阻的阻值和第二电阻的阻值无法满足待检测装置对绝缘电阻的需求,向待检测装置发送关闭指令,该关闭指令可以用于指示待检测装置断开电源与负载的连接,从而保护待检测装置的运行安全。
下面,对计算第一电阻R1和第二电阻R2的并联阻值的过程进行详细说明。
要说明的是,R5和R6串联后与第一电容C1并联,R7和R8串联后与第二电容C2并联,因此,R6两端的第一电压波形中第一时刻对应的数值与第一电容C1两端的电压波形中第一时刻对应的数值呈现比值关系,R7两端的第二电压波形中第一时刻对应的数值与第一电容C2两端的电压波形中第一时刻对应的数值呈现比值关系。因此,为了便于理解,下面以第一电容C1和第二电容C2两端的电压波形为例,对不同时刻的第一电容的电压特征值的计算过程进行详细说明。
处理器向K1和K2的控制端发送第一控制信号,K1和K2响应于第一控制信号处于开关状态一,此时第一电容C1通过R1、R5、R6和R3放电,第二电容C2通过R2、R7和R8充电。
利用上述计算时间常数的公式,计算当前时刻之前预设时长内不同时刻的第一电容电压特征值和/或计算当前时刻之前预设时长内不同时刻的第二电容电压特征值,并利用不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值确定下一切换时刻。
在确定下一切换时刻时,可以向K3发送第二控制信号,K3响应于第二控制信号闭合,此时Y电容(Safety Fixed capacitor)可以通过R9放电,利用上述计算时长常数的方式计算出Y电容的时间常数τ3。
由于τ3=R sum*C3,C3为Y电容的容值,在已知Y电容容值的情况下,可以计算出R sum的数值,R sum为与Y电容并联的多个电阻的并联阻值,在已知R1和R2外其它电阻的情况下,可以计算出R1和R2的并联阻值,并根据R1和R2的并联阻值确定待检测装置的是否出现绝缘失效,以及在确定待检测装置出现绝缘失效时,断开待检测装置电源与负载的连接,保证待检测装置的运行安全。
具体地,当R1和R2的并联阻值小于第二预设绝缘阈值时,当前R1的阻值和R2的阻值无法满足待检测装置对绝缘电阻的需求,确定待检测装置出现绝缘失效。其中,第二预设电阻阈值可以根据待检测装置的应用场景进行设置,本申请这里不做详细介绍。
示例的,若不确定Y电容容值的情况下,可以将R9的阻值设置小于预设阈值,该预设阈值小于包括第一分压支路、第二分压之路、R1、R2、R3和R4在内的任一电阻的阻值,实现当K3闭合时,R sum≈R 9,此时可以通过计算得到的τ3得到Y电容的数值,再利用上述计算并联电阻的方式计算出第一电阻和第二电阻并联阻值。
需要说明的是,根据前述实施例提供的第一分压支路、第二分压支路、以及状态切换单元结构的不同,本申请实施例提供的绝缘电阻检测电路还具有其它几种结构,其它电路结构原理相同,本申请不一一详细介绍。
基于同一发明构思,本申请实施例还提供了一种高压系统的监控装置,如图9所示,该监控系统900可以包括开关模块901、报警模块902、通信模块903和本申请实施例提供的绝缘电阻检测电路200。
其中,绝缘电阻检测电路200可以与通信模块连接903连接,通信模块903可以与报警模块902连接。,开关模块901可以用于连接在高压系统的电源与负载之间。绝缘电阻检测电路200用于检测电源的正极与地之间的第一电阻的阻值和电源的负极与地之间的第二电阻的阻值,并将第一电阻的阻值和第二电阻的阻值发送给通信模块903。通信模块903可以用于在确定第一电阻的阻值或者第二电阻的阻值小于第一预设电阻阈值时,通知报警模块902进行报警;以及在第一电阻的阻值或者第二电阻的阻值小于第二预设电阻阈值时,控制开关模块901断开。
可选的,该高压系统的监控装置900可以与电动汽车的高压系统连接,用于监控电动汽车高压系统的运行以及保护高压系统的运行安全。
基于同一发明构思,本申请实施例还提供了一种绝缘电阻检测方法,如图10所示,本申请实施例提供的图像处理方法如下。该方法可以由图2所示的处理器执行,也可以是与图2所示的绝缘电阻检测电路通信的其它处理器执行。
S1001、处理器获取第一电容对应的第一电压波形和第二电容对应的第二电压波形。 其中,第一电容为待检测装置电源的正极与地之间的电容,第二电容为电源的负极与地之间的电容。
具体地,当第一电压波形和第二电压波形中对应的电压值较小时,处理器可以直接通过第一电容和第二电容获取第一电压波形和第二电压波形;当第一电压波形和第二电压波形中对应的电压值较大时,第一电压波形和第二电压波形中的电压值难以满足处理器对电压值的需求,可以利用电压传感器与第一电压和第二电压连接,得到满足处理器电压需求的第一电压波形和第二电压波形。
在一示例中,当第一电容和第二电容两端的电压数值较大时,可以采用分压电路对第一电容和第二电容两端的电压进行分压操作,得到分压之后的第一电压波形和第二电压波形。
S1002:处理器控制第一电容和第二电容在第一状态或第二状态之间切换。其中,第一状态可以是但不限于第一电容充电且第二电容放电,第二状态可以是但不限于第一电容放电且第二电容充电。
具体的,可以向与第一电容和第二电容连接的开关管或者继电器发送控制信号,实现控制第一电容和第二电容在第一状态和第二状态之间切换。
应理解,由于第一电容和第二电容串联后跨接在待检测装置电源的正极和负极之间,当第一电容和第二电容均放电时,第一电容两端的电压和第二电容两端的电压较小,而待检测电源的正极和负极之间的电压较高,可能会造成此时第一电容和第二电容击穿,造成漏电现象。因此,第一电容和第二电容不会存在同时闭合或者断开的情况。
S1003:处理器根据当前时刻已获取的第一电压波形,计算在当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据当前时刻已获取的第二电压波形,计算在当前时刻之前的设定时长内不同时刻的第二电容电压特征值。其中,第一电容电压特征值可以是但不限于第一电容的时间常数和/或第一电容的电压波形状态。第二电容电压特征值可以是但不限于第二电容的时间常数或第二电容的电压波形状态。
需要说明的是,本申请实施例中已经详细介绍了电压特征值的计算过程,本申请这里对此不作重复介绍。
S1004:处理器根据不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确下一切换时刻。
具体地,将不同时刻的第一电容电压特征值中任意相邻两个电压特征值进行比较,和/或将不同时刻的第二电容电压特征值中任意相邻两个电压特征值进行比较;在确定任意相邻两个电压特征值之差大于预设误差阈值时,将当前时刻确定为下一切换时刻;以及在确定任意相邻两个电压特征值小于或等于预设误差阈值时,确定第一电容的时间常数和/或第二电容的时间常数,并根据所述第一电容的时间常数和/或第二电容的时间常数,确定下一切换时刻。
示例的,若第一电容电压特征值为时间常数,则将不同时刻的第一电容电压特征值的平均值作为第一电容的时间常数。
S1005:处理器在到达下一切换时刻时控制第一电容和第二电容进行状态切换。
具体的,向与第一电容和第二电容连接的开关管或者继电器发送控制指令,控制开关管或者继电器控制第一电容和第二电容进行状态切换。
具体地,处理器在到达下一切换时刻时控制第一电容和第二电容进行状态切换之后, 可以继续获取第一电压波形和第二电压波形,并继续获取的第一电压波形和第二电压波形,确定第一电阻的阻值和第二电阻的阻值。其中,第一电阻为电源的正极与地之间的绝缘电阻,第二电阻为电源的负极与地之间的绝缘电阻,第一电阻的阻值和第二电阻的阻值用于确定是否发生绝缘电阻故障。
具体地,在确定任意相邻两个电压特征值小于或等于预设误差阈值时,第一电阻的阻值和第二电阻的阻值未发生变化,记录第一电容和第二电容在每一切换时刻时第一电压波形和第二电压波形对应的第一电压数值和第二电压数值;以及在确定任意相邻两个电压特征值之差大于预设误差阈值时,确定第一电阻的阻值和第二电阻的阻值发生变化,删除当前时刻之前记录的第一电压数值以及第二电压数值,并重新记录第一电容和第二电容在后续每一切换时刻时第一电压波形和第二电压波形对应的第一电压数值和第二电压数值;利用记录的述第一电压数值和第二电压数值,确定第一电阻的阻值和第二电阻的阻值。
示例的,在确定第一电阻的阻值或第二电阻的阻值小于第一预设绝缘阈值时,确定当前第一电阻的阻值和第二电阻的阻值无法满足待检测装置对绝缘的需求,为了保证待检测装置的运行安全以及操作人员的生命安全,向待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。其中,第一预设绝缘阈值可以根据待检测装置的对绝缘电阻的需求进行设置,本申请这里不做详细介绍。
应理解,在确定当前时刻第一电阻的阻值和第二电阻的阻值发生变化,当前时刻之前获取的第一电压波形和第二电压波形无法计算出第一电阻的阻值和第二电阻的阻值,可以将当前时刻确定为下一切换时刻,从而尽快得到第一电阻的阻值和第二电阻的阻值对应的电压波形,并利用得到的电压波形计算出第一电阻的阻值和第二电阻的阻值,从而在第一电阻的阻值和第二电阻的阻值无法满足待检测装置对绝缘电阻的需求时,可以断开待检测装置电源和负载的连接,从而避免触电事故的发生,保证待检测装置的运行安全。
下面,结合图4所示的电路,对第一电阻的阻值和第二电阻的阻值的计算过程进行详细说明。
在本申请一些实施例中,若当前时刻之前第一电阻的阻值和第二电阻的阻值发生变化,可以对第一电容和第二电容的状态进行切换,获取状态切换后得到第一电压波形和第二电压波形中每一切换时刻对应的第一电压数值和第二电压数值U1 st,U2 st,U1′ st和U2′ st
由于U1 st,U2 st,U1′ st和U2′ st数值已知,且采集的U1 st,U2 st,U1′ st和U2′ st分别为第一电容和第二电容两端的电压分压后的数值,因此,需要先将U1 st的数值,U2 st的数值,U1′ st的数值和U2′ st的数值转换为第一电容两端的电压和第二电容两端的电压,又因为第一电容和第二电容连接在待检测装置电源的正极和负极之间,可以得到下述公式:
Figure PCTCN2020099031-appb-000009
Figure PCTCN2020099031-appb-000010
其中,V HV为待检测装置电源的正极与电源的负极之间的电压,R5的电阻与R8的阻值可以相同,R6和R7的阻值可以相同,联立上面两式,即可求得理论的第一采集电压和第二采集电压的稳态电压值:
Figure PCTCN2020099031-appb-000011
Figure PCTCN2020099031-appb-000012
同理,计算第一电容和第二电容处于第二状态时,第一电压和第二电压的稳态值与电阻的关系式。
Figure PCTCN2020099031-appb-000013
Figure PCTCN2020099031-appb-000014
通过第一电容和第二电容处于第一状态下和第二状态时两个状态下得到的第一电压和第二电压的稳态值U1 st,,U2 st,U1′ st,U2′ st,即可求得R1和R2的值:
Figure PCTCN2020099031-appb-000015
Figure PCTCN2020099031-appb-000016
处理器在计算出第一电阻的阻值和第二电阻的阻值之后,在确定第一电阻的阻值或第二电阻的阻值小于第一预设绝缘阈值时,确定当前第一电阻的阻值和第二电阻的阻值无法满足待检测装置对绝缘电阻的需求,向待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。
应理解,当第一电阻和第二电阻中任一电阻发生变化时,均会影响待检测装置的运行安全,因此,为了减小计算量,可以直接计算表征待检测装置绝缘情况的第一电阻和第二电阻的并联电阻。
具体地,在通过上述公式计算出第一时间常数τ1和第二时间常数τ2之后,由于充放电路径的电阻中包括第一电阻和第二电阻的并联电阻以及绝缘电阻检测电路的电阻,在已知绝缘电阻检测电路的电阻的情况下,可以计算得到第一电阻和第二电阻的并联阻值。
具体的,可以通过对待检测装置电源中的Y电容进行充放电实现,计算第一电阻和第二电阻的并联阻值。
其中,本申请上述实施例已经介绍了利用Y电容计算第一电阻和第二电阻并联阻值的计算过程,本申请这里不做详细介绍。
处理器在计算出第一电阻和第二电阻的并联阻值之后,在确定并联电阻小于第二预设绝缘阈值时,确定第一电阻和第二电阻的并联阻值无法满足待检测装置对绝缘的需求,为了保证待检测装置的运行安全以及操作人员的生命安全,向待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。其中,第二预设绝缘阈值可以根据待检测装置对绝缘电阻的需求进行设置,本申请这里不做详细介绍。
基于图10描述的描述,可参照图11所示的绝缘电阻的检测方法的流程示意图。下面,以根据不同时刻的第一电容电压特征值确定下一切换时刻为例,对绝缘电阻的检测过程进行详细说明。
S1101:获取第一电压波形和第二电压波形。
S1102:利用当前时刻以获取的第一电压波形,计算在所述当前时刻之前的设定时长内不同时刻的第一电容电压特征值。
S1103:利用不同时刻的第一电容电压特征值检测第一电阻的阻值和第二电阻的阻值是否发生变化,若是执行S1104,否则执行S1106。
S1104:将当前时刻确定为下一切换时刻。
S1105:将当前时刻存储的第一电压数值和第二电压数值删除。
S1106:在确定第一电阻的阻值未发生变化时,计算第一电容的时间常数,并利用第一电容的时间常数,计算下一切换时刻。
S1107:在到达下一切换时刻时,对第一电容和第二电容的状态进行切换。
S1108:存储当前时刻的第一电压数值和第二电压数值。
S1109:检测存储的第一电压数值和第二电压数值的数量是否达到四个,若是执行S1110,否则执行S1101。
S1110、利用存储的第一电压数值和第二电压数值,计算第一电阻的阻值和第二电阻的阻值。
基于同一技术构思,如图12所示,本申请实施例还提供了一种绝缘电阻检测装置,该绝缘电阻检测装置1200。一种设计中,该绝缘电阻检测装置1200可以包括获取单元1201、处理单元1202和计算单元1203。
获取模块1201可以用于获取第一电压波形和第二电压波形。第一电压为待检测电源的正极与地之间的第一电容两端的电压,第二电压为电源的负极与地之间的第二电容两端的电压。处理单元1202可以用于控制第一电容和第二电容在第一状态或第二状态之间切换。第一状态为第一电容充电且第二电容放电,第二状态为第一电容放电且第二电容充电。计算单元1203可以用于根据当前时刻获取模块1201已获取的第一电压波形,计算在当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据当前时刻获取模块1201已获取的第二电压波形,计算在当前时刻之前的设定时长内不同时刻的第二电容电压特征值。
处理单元1202还可以用于根据计算单元1203输出的不同时刻的第一电容电压特征值和/或不同时刻的第二电容电压特征值,确定第一电容和第二电容的下一切换时刻,并在到达下一切换时刻时控制第一电容和第二电容进行状态切换。
获取的第二电压波形,计算在当前时刻之前的设定时长内不同时刻的第二电容电压特征值。
获取单元1201还用于:在到达下一切换时刻时控制第一电容和第二电容进行状态切换之后,继续获取第一电压波形和第二电压波形。处理单元1202还用于根据获取单元1201继续获取的第一电压波形和第二电压波形,确定第一电阻的阻值和第二电阻的阻值。第一电阻为电源的正极与地之间的绝缘电阻,第二电阻为电源的负极与地之间的绝缘电阻,第一电阻的阻值和第二电阻的阻值用于确定是否发生绝缘电阻故障。
可选地,处理单元1202具体用于:将不同时刻的第一电容电压特征值中任意相邻两个电压特征值进行比较,和/或将不同时刻的第二电容电压特征值中任意相邻两个电压特征值进行比较;在确定任意相邻两个电压特征值之差大于预设误差阈值时,将当前时刻确定为下一切换时刻;以及在确定任意相邻两个电压特征值小于或等于预设误差阈值时,确定第一电容的时长常数和/或第二电容的时间常数,并根据第一电容的时间常数和/或第二电 容的时间常数,确定下一切换时刻。
可选地,处理单元1202具体用于:在确定任意相邻两个电压特征值小于或等于预设误差阈值时,记录第一电容和第二电容在每一切换时刻时第一电压波形和第二电压波形对应的第一电压数值和第二电压数值;以及在确定任意相邻两个电压特征值之差大于预设误差阈值时,删除当前时刻之前记录的第一电压数值以及第二电压数值,并重新记录第一电容和第二电容在后续每一切换时刻时第一电压波形和第二电压波形对应的第一电压数值和第二电压数值;利用记录的述第一电压数值和第二电压数值,确定第一电阻的阻值和第二电阻的阻值。
可选地,处理单元1202还用于:在确定第一电阻的阻值或第二电阻的阻值小于第一预设绝缘阈值时,向与待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。
可选地,处理单元1202还用于:根据获取单元1201继续获取的第一电压波形和第二电压波形,确定第一电阻和第二电阻的并联阻值;在确定并联阻值小于第二预设绝缘阈值时,向与待检测装置发送关闭指令,关闭指令用于指示待检测装置断开电源与负载的连接。
可选地,第一电容电压特征值包括以下一个或多个:第一电容的时间常数和第一电容的电压波形状态;第二电容电压特征值包括以下一个或多个:第二电容的时间常数和第二电容的电压波形状态;第一电容的波形状态表征第一电容两端电压的波动趋势,第二电容的波形状态表征第二电容两端的波形趋势。
本申请实施例中对模块的划分是示意性的,仅仅为一种逻辑功能划分,实际实现时可以有另外的划分方式,另外,在本申请各个实施例中的各功能模块可以集成在一个处理器中,也可以是单独物理存在,也可以两个或两个以上模块集成在一个模块中。上述集成的模块既可以采用硬件的形式实现,也可以采用软件功能模块的形式实现。
本申请实施例提供了一种计算机可读存储介质,存储有计算机程序,该计算机程序包括用于执行上述方法实施例的指令。
本申请实施例提供了一种包含指令的计算机程序产品,当其在计算机上运行时,使得计算机执行上述方法实施例。
本领域内的技术人员应明白,本申请的实施例可提供为方法、系统、或计算机程序产品。因此,本申请可采用完全硬件实施例、完全软件实施例、或结合软件和硬件方面的实施例的形式。而且,本申请可采用在一个或多个其中包含有计算机可用程序代码的计算机可用存储介质(包括但不限于磁盘存储器、CD-ROM、光学存储器等)上实施的计算机程序产品的形式。
本申请是参照根据本申请实施例的方法、设备(系统)、和计算机程序产品的流程图和/或方框图来描述的。应理解可由计算机程序指令实现流程图和/或方框图中的每一流程和/或方框、以及流程图和/或方框图中的流程和/或方框的结合。可提供这些计算机程序指令到通用计算机、专用计算机、嵌入式处理机或其他可编程数据处理设备的处理器以产生一个机器,使得通过计算机或其他可编程数据处理设备的处理器执行的指令产生用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的装置。
这些计算机程序指令也可存储在能引导计算机或其他可编程数据处理设备以特定方式工作的计算机可读存储器中,使得存储在该计算机可读存储器中的指令产生包括指令装 置的制造品,该指令装置实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能。
这些计算机程序指令也可装载到计算机或其他可编程数据处理设备上,使得在计算机或其他可编程设备上执行一系列操作步骤以产生计算机实现的处理,从而在计算机或其他可编程设备上执行的指令提供用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的步骤。
尽管已描述了本申请的优选实施例,但本领域内的技术人员一旦得知了基本创造性概念,则可对这些实施例作出另外的变更和修改。所以,所附权利要求意欲解释为包括优选实施例以及落入本申请范围的所有变更和修改。
显然,本领域的技术人员可以对本申请实施例进行各种改动和变型而不脱离本申请实施例的精神和范围。这样,倘若本申请实施例的这些修改和变型属于本申请权利要求及其等同技术的范围之内,则本申请也意图包含这些改动和变型在内。

Claims (24)

  1. 一种绝缘电阻检测电路,其特征在于,包括:状态控制单元、第一分压支路、第二分压支路和处理器;
    所述状态控制单元跨接在待检测装置的电源的正极和负极之间,所述状态控制单元用于在所述处理器的控制下在第一状态或第二状态之间切换,所述状态控制单元处于所述第一状态时第一电容充电且第二电容放电,所述状态控制单元处于所述第二状态时所述第一电容放电且所述第二电容充电,所述第一电容为所述电源的正极与地之间的电容,所述第二电容为所述电源的负极与所述地之间的电容;
    所述第一分压支路用于与所述第一电容并联,并用于对所述第一电容两端的电压进行分压,得到第一电压波形;
    所述第二分压支路用于与所述第二电容并联,并用于对所述第二电容两端的电压进行分压,得到第二电压波形;
    所述处理器分别与所述状态控制单元、所述第一分压支路和所述第二分压支路连接,所述处理器用于:根据当前时刻已得到的所述第一电压波形,计算所述当前时刻之前的设定时长内不同时刻的所述第一电容电压特征值;以及根据所述当前时刻已得到的所述第二电压波形,计算所述当前时刻之前的所述设定时长内不同时刻的所述第二电容电压特征值;并根据所述不同时刻的第一电容电压特征值和/或所述所述不同时刻的第二电容电压特征值,确定下一切换时刻,并在到达所述下一切换时刻时控制所述状态控制单元进行状态切换。
  2. 如权利要求1所述的电路,其特征在于,所述处理器还用于:
    根据在到达所述下一切换时刻之后在所述第一状态和所述第二状态时已得到的第一电压波形和已得到的第二电压波形,确定第一电阻的阻值和第二电阻的阻值;所述第一电阻为所述电源的正极与地之间的绝缘电阻,所述第二电阻为所述电源的负极与所述地之间的绝缘电阻,所述第一电阻和阻值和所述第二电阻的阻值用于确定是否发生绝缘电阻故障。
  3. 如权利要求1或2所述的电路,其特征在于,所述状态控制单元包括:第一开关单元和第二开关单元;
    所述第一开关单元的第一端与所述电源的正极连接,所述第一开关单元的第二端与所述地连接;
    所述第二开关单元的第二端与所述电源的负极连接,所述第二开关单元的第二端与所述地连接;
    所述第一开关单元闭合且所述第二开关单元断开时,所述状态控制单元处于所述第一状态;所述第一开关单元断开且所述第二开关单元闭合时,所述状态控制单元处于所述第二状态。
  4. 如权利要求3所述的电路,其特征在于,所述第一开关单元包括:第一开关和第三电阻;
    所述第三电阻的第一端与所述电源的正极连接,所述第三电阻的第二端与所述第一开关的第一端连接;
    所述第一开关的第二端与所述地连接,所述第一开关的控制端与所述处理器连接。
  5. 如权利要求3或4所述的电路,其特征在于,所述第二开关单元包括:第二开关 和第四电阻;
    所述第二开关的第一端与所述地连接,所述第二开关的第二端与所述第四电阻的第一端连接,所述第二开关的控制端与所述处理器连接;
    所述第四电阻的第二端与所述电源的负极连接。
  6. 如权利要求1-5中任一项所述的电路,其特征在于,所述第一分压支路包括:第五电阻和第六电阻;
    所述第五电阻的一端与所述电源的正极连接,所述第五电阻的第二端分别与所述第六电阻的第一端和所述处理器连接;
    所述第六电阻的第二端与所述地和所述处理器连接。
  7. 如权利要求1-6中任一项所述的电路,其特征在于,所述第二分压支路包括:第七电阻和第八电阻;
    所述第七电阻的第一端与所述地和所述处理器连接,所述第七电阻的第二端分别与所述第八电阻的第一端和所述处理器连接;
    所述第八电阻的第二端与所述电源的负极连接。
  8. 如权利要求2所述的电路,其特征在于,所述电路还包括:第九电阻和第三开关;
    所述第九电阻的第一端分别与所述电源的正极和所述处理器连接,所述第九电阻的第二端分别与所述第三开关的第一端和所述处理器连接,所述第九电阻的阻值小于预设阈值;
    所述第三开关的第二端与所述地连接,所述第三开关的控制端与所述处理器连接;
    所述处理器还用于:控制所述第三开关闭合和断开;
    所述处理器根据在到达所述下一切换时刻之后在所述第一状态和所述第二状态时已得到的第一电压波形和第二电压波形,确定第一电阻的阻值和第二电阻的阻值时,具体用于:
    根据在到达所述下一切换时刻之后在所述第一状态和所述第二状态时已得到的第一电压波形、已得到的第二电压波形以及所述第三开关闭合时所述第九电阻两端的电压波形,计算所述第一电阻和所述第二电阻的并联阻值,所述并联阻值用于确定是否发生绝缘电阻故障。
  9. 一种高压系统的监控装置,其特征在于,包括:开关模块、报警模块、通信模块和如权利要求1-8中任一项所述的绝缘电阻检测电路;
    所述开关模块用于连接在所述高压系统的电源与负载之间;
    所述绝缘电阻检测电路,与所述通信模块连接,用于检测所述电源的正极与地之间的第一电阻的阻值和所述电源的负极与所述地之间的第二电阻的阻值,并将第一电阻的阻值和所述第二电阻的阻值发送给所述通信模块;
    所述通信模块与所述报警模块连接,所述通信模块用于在确定所述第一电阻的阻值或者所述第二电阻的阻值小于第一预设电阻阈值时,通知所述报警模块进行报警;以及在所述第一电阻的阻值或者所述第二电阻的阻值小于第二预设电阻阈值时,控制所述开关模块断开。
  10. 一种绝缘电阻的检测方法,其特征在于,包括:
    获取第一电容对应的第一电压波形和第二电容对应的第二电压波形,所述第一电容为待检测装置的电源的正极与地之间的电容,所述第二电容为所述电源的负极与所述地之间的电容;
    控制所述第一电容和所述第二电容在第一状态或第二状态之间切换,所述第一状态为所述第一电容充电且所述第二电容放电,所述第二状态为所述第一电容放电且所述第二电容充电;
    根据当前时刻已获取的第一电压波形,计算在所述当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据所述当前时刻已获取的第二电压波形,计算在所述当前时刻之前的所述设定时长内不同时刻的第二电容电压特征值;
    根据所述不同时刻的第一电容电压特征值和/或所述不同时刻的第二电容电压特征值,确定下一切换时刻;
    在到达所述下一切换时刻时控制所述第一电容和所述第二电容进行状态切换。
  11. 如权利要求10所示的方法,其特征在于,所述在到达所述下一切换时刻时控制所述第一电容和所述第二电容进行状态切换之后,还包括:
    继续获取第一电压波形和第二电压波形;
    根据继续获取的第一电压波形和第二电压波形,确定第一电阻的阻值和第二电阻的阻值,所述第一电阻为所述电源的正极与地之间的绝缘电阻,所述第二电阻为所述电源的负极与所述地之间的绝缘电阻,所述第一电阻的阻值和所述第二电阻的阻值用于确定是否发生绝缘电阻故障。
  12. 如权利要求11所述的方法,其特征在于,所述根据所述不同时刻的第一电容电压特征值和/或所述不同时刻的第二电容电压特征值,确定下一切换时刻,包括:
    将所述不同时刻的第一电容电压特征值中任意相邻两个电压特征值进行比较,和/或将所述不同时刻的第二电容电压特征值中任意相邻两个电压特征值进行比较;
    在确定任意相邻两个电压特征值之差大于预设误差阈值时,将所述当前时刻确定为所述下一切换时刻;以及
    在确定任意相邻两个电压特征值小于或等于所述预设误差阈值时,确定所述第一电容的时间常数和/或所述第二电容的时间常数,并根据所述第一电容的时间常数和/或所述第二电容的时长常数,确定所述下一切换时刻。
  13. 如权利要求12所述的方法,其特征在于,所述根据继续获取的第一电压波形和第二电压波形,确定第一电阻的阻值和第二电阻的阻值,包括:
    在确定任意相邻两个电压特征值小于或等于所述预设误差阈值时,记录所述第一电容和所述第二电容在每一切换时刻时所述第一电压波形和所述第二电压波形对应的第一电压数值和第二电压数值;以及
    在确定任意相邻两个电压特征值之差大于预设误差阈值时,删除所述当前时刻之前记录的第一电压数值以及第二电压数值,并重新记录所述第一电容和所述第二电容在后续每一切换时刻时所述第一电压波形和所述第二电压波形对应的第一电压数值和第二电压数值;
    利用记录的述第一电压数值和所述第二电压数值,确定所述第一电阻的阻值和所述第二电阻的阻值。
  14. 如权利要求11-13中任一项所述的方法,其特征在于,所述方法还包括:
    在确定所述第一电阻的阻值或所述第二电阻的阻值小于第一预设绝缘阈值时,向所述待检测装置发送关闭指令,所述关闭指令用于指示所述待检测装置断开所述电源与负载的连接。
  15. 如权利要求11-13中任一项所述的方法,其特征在于,所述继续获取第一电压波形和第二电压波形之后,还包括:
    根据继续获取的第一电压波形和第二电压波形,确定所述第一电阻和所述第二电阻的并联阻值;
    在确定所述并联阻值小于第二预设绝缘阈值时,向所述待检测装置发送关闭指令,所述关闭指令用于指示所述待检测装置断开所述电源与负载的连接。
  16. 如权利要求10-15中任一项所述的方法,其特征在于,所述第一电容电压特征值包括以下一个或多个:所述第一电容的时间常数和第一电容的电压波形状态;
    所述第二电容电压特征值包括以下一个或多个:所述第二电容的时间常数和第二电容的电压波形状态;
    所述第一电容的波形状态表征所述第一电容两端电压的波动趋势,所述第二电容的波形状态表征所述第二电容两端电压的波形趋势。
  17. 一种绝缘电阻检测装置,其特征在于,包括:获取单元、处理单元和计算单元;
    所述获取单元,用于获取第一电容对应的第一电压波形和第二电容对应的第二电压波形,所述第一电容为待检测电源的正极与地之间的电容,所述第二电容为所述电源的负极与所述地之间的电容;
    所述处理单元,用于控制所述第一电容和所述第二电容在第一状态或第二状态之间切换,所述第一状态为所述第一电容充电且所述第二电容放电,所述第二状态为所述第一电容放电且所述第二电容充电;
    所述计算单元,用于根据当前时刻所述获取模块已获取的第一电压波形,计算在所述当前时刻之前的设定时长内不同时刻的第一电容电压特征值;以及根据所述当前时刻所述获取模块已获取的第二电压波形,计算在所述当前时刻之前的所述设定时长内不同时刻的第二电容电压特征值;
    所述处理单元还用于根据所述计算单元输出的所述不同时刻的第一电容电压特征值和/或所述不同时刻的第二电容电压特征值,确定下一切换时刻;以及在到达所述下一切换时刻时控制所述第一电容和所述第二电容进行状态切换。
  18. 如权利要求17所述的装置,其特征在于,所述获取单元还用于:在到达所述下一切换时刻时控制所述第一电容和所述第二电容进行状态切换之后,继续获取第一电压波形和第二电压波形;
    所述处理单元还用于:根据所述获取单元继续获取的第一电压波形和第二电压波形,确定第一电阻的阻值和第二电阻的阻值,第一电阻为电源正极与地之间的绝缘电阻,第二电阻为电源负极与地之间的绝缘电阻,第一电阻的阻值和第二电阻的阻值用于确定是否发生绝缘电阻故障。
  19. 如权利要求18所述的装置,其特征在于,所述处理单元具体用于:
    将所述不同时刻的第一电容电压特征值中任意相邻两个电压特征值进行比较,和/或将所述不同时刻的第二电容电压特征值中任意相邻两个电压特征值进行比较;
    在确定任意相邻两个电压特征值之差大于预设误差阈值时,将所述当前时刻确定为所述下一切换时刻;以及
    在确定任意相邻两个电压特征值小于或等于所述预设误差阈值时,确定所述第一电容 的时长常数和/或所述第二电容的时间常数,并根据所述第一电容的时间常数和/或所述第二电容的时间常数,确定所述下一切换时刻。
  20. 如权利要求19所述的装置,其特征在于,所述处理单元具体用于:
    在确定任意相邻两个电压特征值小于或等于所述预设误差阈值时,记录所述第一电容和所述第二电容在每一切换时刻时所述第一电压波形和所述第二电压波形对应的第一电压数值和第二电压数值;以及
    在确定任意相邻两个电压特征值之差大于预设误差阈值时,删除所述当前时刻之前记录的第一电压数值以及第二电压数值,并重新记录所述第一电容和所述第二电容在后续每一切换时时所述第一电压波形和所述第二电压波形对应的第一电压数值和第二电压数值;
    利用记录的述第一电压数值和所述第二电压数值,确定所述第一电阻的阻值和所述第二电阻的阻值。
  21. 如权利要求18-20中任一项所述的装置,其特征在于,所述处理单元还用于:
    在确定所述第一电阻的阻值或所述第二电阻的阻值小于第一预设绝缘阈值时,向与所述待检测装置发送关闭指令,所述关闭指令用于指示所述待检测装置断开所述电源与负载的连接。
  22. 如权利要求18-20中任一项所述的装置,其特征在于,所述处理单元还用于:
    根据继续获取的第一电压波形和第二电压波形,确定所述第一电阻和所述第二电阻的并联阻值;
    在确定所述并联阻值小于第二预设绝缘阈值时,向与所述待检测装置发送关闭指令,所述关闭指令用于指示所述待检测装置断开所述电源与负载的连接。
  23. 如权利要求17-22中任一项所述的装置,其特征在于,所述第一电容电压特征值包括以下一个或多个:所述第一电容的时间常数和第一电容的电压波形状态;所述第二电容电压特征值包括以下一个或多个:所述第二电容的时间常数和第二电容的电压波形状态;所述第一电容的波形状态表征所述第一电容两端电压的波动趋势,所述第二电容的波形状态表征所述第二电容两端电压的波形趋势。
  24. 一种计算机可读存储介质,其特征在于,所述计算机存储介质中存储有计算机可读指令,当所述计算机可读指令在计算机上运行时,如权利要求10~16中任一项所述的方法被执行。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117665396A (zh) * 2024-01-31 2024-03-08 徐州徐工汽车制造有限公司 用于动力电池的绝缘电阻检测电路、方法、装置及介质

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114660504B (zh) * 2022-04-08 2023-07-07 东方电气集团东方电机有限公司 绝缘监测回路的检测方法、装置、电子设备及存储介质
CN115078844A (zh) * 2022-06-01 2022-09-20 中国第一汽车股份有限公司 Y电容的测试方法、测试设备、存储介质及处理器
CN117192314B (zh) * 2023-11-03 2024-04-02 广州疆海科技有限公司 基于绝缘检测电路的绝缘检测方法、装置和计算机设备
CN118091523A (zh) * 2024-04-25 2024-05-28 宁德时代新能源科技股份有限公司 检测电路、检测设备及检测方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110012606A1 (en) * 2009-07-15 2011-01-20 Yazaki Corporation Insulation state detector
CN107407713A (zh) * 2015-11-16 2017-11-28 株式会社Lg 化学 绝缘电阻测量系统和设备
CN109633276A (zh) * 2018-12-28 2019-04-16 蜂巢能源科技有限公司 基于全桥绝缘检测电路的绝缘电阻检测方法和装置
CN109765430A (zh) * 2019-03-26 2019-05-17 北京经纬恒润科技有限公司 一种绝缘阻抗检测系统及检测方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101473396B1 (ko) * 2012-05-15 2014-12-16 주식회사 엘지화학 확장형 칼만 필터를 이용한 배터리 절연 저항 측정 장치 및 방법
KR20130128597A (ko) * 2012-05-17 2013-11-27 현대모비스 주식회사 절연저항 센싱회로 및 이를 포함하는 배터리관리시스템
CN210742435U (zh) * 2019-09-09 2020-06-12 北京新能源汽车股份有限公司 一种电动汽车的绝缘检测系统及汽车

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110012606A1 (en) * 2009-07-15 2011-01-20 Yazaki Corporation Insulation state detector
CN107407713A (zh) * 2015-11-16 2017-11-28 株式会社Lg 化学 绝缘电阻测量系统和设备
CN109633276A (zh) * 2018-12-28 2019-04-16 蜂巢能源科技有限公司 基于全桥绝缘检测电路的绝缘电阻检测方法和装置
CN109765430A (zh) * 2019-03-26 2019-05-17 北京经纬恒润科技有限公司 一种绝缘阻抗检测系统及检测方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4155739A4 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117665396A (zh) * 2024-01-31 2024-03-08 徐州徐工汽车制造有限公司 用于动力电池的绝缘电阻检测电路、方法、装置及介质
CN117665396B (zh) * 2024-01-31 2024-06-07 徐州徐工汽车制造有限公司 用于动力电池的绝缘电阻检测电路、方法、装置及介质

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