CN-121721442-B - Insulation detection method, device, equipment and medium based on vehicle-mounted charger

CN121721442BCN 121721442 BCN121721442 BCN 121721442BCN-121721442-B

Abstract

The embodiment of the application discloses an insulation detection method, device, equipment and medium based on an on-vehicle charger. The method comprises the steps of obtaining a first voltage between an L line and a PE, a second voltage between an N line and the PE and a third voltage between the L line and the N line when the vehicle-mounted charger is in an inversion working state, determining a first phase angle corresponding to the first voltage and a second phase angle corresponding to the second voltage based on the first voltage, the second voltage and the third voltage, determining a first insulation resistance between the L line and the PE based on the first phase angle, the second phase angle, a first module corresponding to the first voltage, a second module corresponding to the second voltage and a preset capacitance parameter, and determining a second insulation resistance between the N line and the PE, and performing insulation detection on an alternating current side of the vehicle-mounted charger according to the first insulation resistance and the second insulation resistance to obtain an insulation detection result. The non-invasive real-time insulation detection of the vehicle-mounted charger in the inversion working state is realized through the scheme.

Inventors

GAN JIANHONG
ZHOU ZILONG
WANG WENXIN
LIN GUIHONG
LIU XIN

Assignees

深圳艾为电气技术股份有限公司

Dates

Publication Date: 20260508
Application Date: 20260226

Claims (8)

1. An insulation detection method based on an on-vehicle charger is characterized by comprising the following steps: when the vehicle-mounted charger is in an inversion working state, acquiring a first voltage between an L line and a PE, a second voltage between an N line and the PE and a third voltage between the L line and the N line, wherein the L line and the N line are alternating current output ends of an inversion circuit in the vehicle-mounted charger, and the PE is connected with a metal shell of a vehicle; determining a first phase angle corresponding to the first voltage and a second phase angle corresponding to the second voltage based on the first voltage, the second voltage and the third voltage; Determining a first insulation resistance between the L line and the PE and a second insulation resistance between the N line and the PE based on the first phase angle, the second phase angle, a first module value corresponding to the first voltage, a second module value corresponding to the second voltage and a preset capacitance parameter; performing insulation detection on the alternating current side of the vehicle-mounted charger according to the first insulation resistor and the second insulation resistor to obtain an insulation detection result; The determining a first insulation resistance between the L line and the PE and a second insulation resistance between the N line and the PE based on the first phase angle, the second phase angle, a first modulus value corresponding to the first voltage, a second modulus value corresponding to the second voltage, and a preset capacitance parameter, includes: Determining a first insulation conductance according to the first phase angle, the second phase angle, the first module value, the second module value and the capacitance parameter based on a preset first insulation parameter calculation formula; Determining a second insulation conductance according to the first phase angle, the second phase angle, the first module value, the second module value and the capacitance parameter based on a preset second insulation parameter calculation formula; determining an inverse of the first insulation conductance as the first insulation resistance and an inverse of the second insulation conductance as the second insulation resistance; The first insulation parameter calculation formula is as follows: ; wherein Y 1 is the first insulated conductance, x is the first modulus, Y is the second modulus, For the first phase angle of the phase of the wave, For the second phase angle of the phase of the light, For the capacitance parameter, and cl=cn=c0, =Ωcl=ωcn, CL is the Y capacitance of the L line pair PE, CN is the Y capacitance of the N line pair PE, C0 is the Y capacitance value, ω is the output ac frequency; The second insulation parameter calculation formula is: ; wherein Y 2 is the second insulated conductance.
2. The method of claim 1, wherein the determining a first phase angle corresponding to the first voltage and a second phase angle corresponding to the second voltage based on the first voltage, the second voltage, and the third voltage comprises: constructing a phasor triangle based on the first voltage, the second voltage, and the third voltage; The first phase angle and the second phase angle are calculated based on the phasor triangle.
3. The method of claim 2, wherein the calculating the first phase angle and the second phase angle based on the phasor triangle comprises: Acquiring a first module value of the first voltage, a second module value of the second voltage and a third module value of the third voltage in the phasor triangle; And determining the first phase angle and the second phase angle according to the first module value, the second module value, the third module value and a preset phase angle calculation formula.
4. The method according to claim 1, wherein the performing insulation detection on the ac side of the vehicle-mounted charger according to the first insulation resistance and the second insulation resistance to obtain an insulation detection result includes: If the first insulation resistance or the second insulation resistance is smaller than a preset resistance threshold, determining an insulation detection failure result as the insulation detection result; and if the first insulation resistance and the second insulation resistance are both larger than or equal to the preset resistance threshold, determining an insulation detection passing result as the insulation detection result.
5. The method according to claim 4, wherein after the insulation detection non-passing result is determined as the insulation detection result, the method further comprises: Triggering the power failure protection instruction of the vehicle-mounted charger.
6. An insulation detection device based on an on-vehicle charger, comprising: The receiving and transmitting unit is used for acquiring a first voltage between an L line and a PE, a second voltage between an N line and the PE and a third voltage between the L line and the N line when the vehicle-mounted charger is in an inversion working state, wherein the L line and the N line are alternating current output ends of an inversion circuit in the vehicle-mounted charger, and the PE is connected with a metal shell of a vehicle; The processing unit is used for determining a first phase angle corresponding to the first voltage and a second phase angle corresponding to the second voltage based on the first voltage, the second voltage and the third voltage, determining a first insulation resistance between the L line and the PE and a second insulation resistance between the N line and the PE based on the first phase angle, the second phase angle, a first module value corresponding to the first voltage, a second module value corresponding to the second voltage and a preset capacitance parameter, and performing insulation detection on an alternating current side of the vehicle-mounted charger according to the first insulation resistance and the second insulation resistance to obtain an insulation detection result; The processing unit is specifically configured to, when executing the steps of determining a first insulation resistance between the L line and the PE and determining a second insulation resistance between the N line and the PE based on the first phase angle, the second phase angle, the first modulus corresponding to the first voltage, the second modulus corresponding to the second voltage, and a preset capacitance parameter: Determining a first insulation conductance according to the first phase angle, the second phase angle, the first module value, the second module value and the capacitance parameter based on a preset first insulation parameter calculation formula; Determining a second insulation conductance according to the first phase angle, the second phase angle, the first module value, the second module value and the capacitance parameter based on a preset second insulation parameter calculation formula; determining an inverse of the first insulation conductance as the first insulation resistance and an inverse of the second insulation conductance as the second insulation resistance; The first insulation parameter calculation formula is as follows: ; wherein Y 1 is the first insulated conductance, x is the first modulus, Y is the second modulus, For the first phase angle of the phase of the wave, For the second phase angle of the phase of the light, For the capacitance parameter, and cl=cn=c0, =Ωcl=ωcn, CL is the Y capacitance of the L line pair PE, CN is the Y capacitance of the N line pair PE, C0 is the Y capacitance value, ω is the output ac frequency; The second insulation parameter calculation formula is: ; wherein Y 2 is the second insulated conductance.
7. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the vehicle charger based insulation detection method of any one of claims 1-5 when the computer program is executed.
8. A storage medium storing a computer program comprising program instructions that when executed by a processor cause the processor to perform the vehicle charger-based insulation detection method of any one of claims 1-5.

Description

Insulation detection method, device, equipment and medium based on vehicle-mounted charger Technical Field The present application relates to the field of insulation detection technologies, and in particular, to an insulation detection method, apparatus, device, and medium based on an on-vehicle charger. Background With the popularization of electric vehicles, an On-Board Charger (OBC) is used as a key component for connecting an electric network and a high-voltage battery of the vehicle, and is responsible for converting the electric network alternating current into direct current required by the power battery during normal operation, so that the safety of the electric network alternating current is of great importance. High voltage systems (typically 300V-800V) are extremely sensitive to insulation failure, and reduced insulation performance can lead to leakage current, risk of electrical shock or system shorting, severely threatening personal and equipment safety. The vehicle-mounted battery can be used externally, at the moment, the OBC is in an inversion state and is responsible for converting direct current of the battery into external alternating current, for example, a vehicle is used as a mobile power station in camping, power failure and other scenes to supply power to household appliances such as an electric cooker, illumination, a computer and the like through an alternating current output port of the OBC, and at the moment of peak load of a power grid, the electric energy in the vehicle battery is inverted into alternating current to be fed back to the power grid to participate in power grid regulation, or another electric vehicle is subjected to emergency charging. In order to avoid the risk of electric shock when a user touches a vehicle, a method is needed to realize non-invasive real-time insulation detection on the ac output side of the vehicle-mounted charger in an inversion working state. Disclosure of Invention The embodiment of the application provides an insulation detection method, an insulation detection device, insulation detection equipment and an insulation detection medium based on an on-vehicle charger, which can realize non-invasive real-time insulation detection on an alternating current output side of the on-vehicle charger in an inversion working state. In a first aspect, an embodiment of the present application provides an insulation detection method based on an on-vehicle charger, where when the on-vehicle charger is in an inversion working state, a first voltage between an L line and a PE, a second voltage between an N line and the PE, and a third voltage between the L line and the N line are obtained, where the L line and the N line are ac output ends of an inverter circuit in the on-vehicle charger, and the PE is connected with a metal casing of a vehicle; determining a first phase angle corresponding to the first voltage and a second phase angle corresponding to the second voltage based on the first voltage, the second voltage and the third voltage; Determining a first insulation resistance between the L line and the PE and a second insulation resistance between the N line and the PE based on the first phase angle, the second phase angle, a first module value corresponding to the first voltage, a second module value corresponding to the second voltage and a preset capacitance parameter; and performing insulation detection on the alternating current side of the vehicle-mounted charger according to the first insulation resistor and the second insulation resistor to obtain an insulation detection result. In some embodiments, the determining a first phase angle corresponding to the first voltage and a second phase angle corresponding to the second voltage based on the first voltage, the second voltage, and the third voltage includes: constructing a phasor triangle based on the first voltage, the second voltage, and the third voltage; The first phase angle and the second phase angle are calculated based on the phasor triangle. In some embodiments, the calculating the first phase angle and the second phase angle based on the phasor triangle comprises: Acquiring a first module value of the first voltage, a second module value of the second voltage and a third module value of the third voltage in the phasor triangle; And determining the first phase angle and the second phase angle according to the first module value, the second module value, the third module value and a preset phase angle calculation formula. In some embodiments, the determining the first insulation resistance between the L line and the PE and the second insulation resistance between the N line and the PE based on the first phase angle, the second phase angle, the first modulus value corresponding to the first voltage, the second modulus value corresponding to the second voltage, and a preset capacitance parameter includes: Determining a first insulation conductance according to the first phase angle, the sec