CN115166432B

CN115166432B - Method, circuit and system for detecting insulation of high-voltage power supply loop of automobile and automobile

Info

Publication number: CN115166432B
Application number: CN202210741283.XA
Authority: CN
Inventors: 邓磊; 郭洪江; 谢哲锋
Original assignee: Zhaoqing Xiaopeng Automobile Co Ltd
Current assignee: Zhaoqing Xiaopeng Automobile Co Ltd
Priority date: 2022-06-28
Filing date: 2022-06-28
Publication date: 2024-03-08
Anticipated expiration: 2042-06-28
Also published as: CN115166432A

Abstract

The application relates to an insulation detection method, circuit and system for a high-voltage power supply loop of an automobile and the automobile. The high-voltage power supply loop comprises a power supply positive terminal interface, a power battery pack and a power supply negative terminal interface, wherein electrodes at two ends of the power battery pack are respectively connected with the power supply positive terminal interface and the power supply negative terminal interface, a central point of the power battery pack is connected with one end of a measuring resistor, and the other end of the measuring resistor is grounded; the method comprises the following steps: acquiring a first leakage current measured by a first leakage current sensor and a second leakage current measured by a second leakage current sensor; the first leakage current sensor is respectively connected with the power supply positive terminal interface and the central point, and the second leakage current sensor is respectively connected with the power supply negative terminal interface and the central point; and obtaining the high-voltage insulation state condition of the high-voltage power supply loop according to the first leakage current and the second leakage current. The scheme that this application provided can be used for carrying out high voltage insulation state and detects and need not to pour into the detected signal into, can ensure high voltage power supply return circuit normal operating.

Description

Method, circuit and system for detecting insulation of high-voltage power supply loop of automobile and automobile

Technical Field

The application relates to the technical field of insulation detection, in particular to an insulation detection method, circuit and system for a high-voltage power supply loop of an automobile and the automobile.

Background

The high-voltage power supply loop in the new energy electric automobile comprises a power battery pack, and the power battery pack is formed by connecting a large number of electric cores in series and parallel. The internal connection of the high-voltage power supply loop of the automobile is complicated, and insulation faults are easy to occur. In order to ensure the safety of automobiles and users, the high-voltage power supply circuit needs to be subjected to high-voltage insulation state detection.

In the injection type insulation detection scheme in the related art, detection signals (such as voltage and current) are injected into a high-voltage power supply loop where a power battery pack is located, so that the high-voltage insulation state of the high-voltage power supply loop is detected.

However, the injection type insulation detection scheme may affect the operation of the high voltage power supply loop and even raise a safety risk.

Disclosure of Invention

In order to solve or partially solve the problems existing in the related art, the application provides an insulation detection method, a circuit, a system and an automobile for a high-voltage power supply loop, which can detect the high-voltage insulation state of the high-voltage power supply loop without injecting detection signals, and can ensure the normal operation of the high-voltage power supply loop.

The first aspect of the present application provides an insulation detection method for a high-voltage power supply loop of an automobile, where the high-voltage power supply loop includes a power supply positive terminal interface, a power battery pack and a power supply negative terminal interface, two end electrodes of the power battery pack are respectively connected with the power supply positive terminal interface and the power supply negative terminal interface, a center point of the power battery pack is connected with one end of a measurement resistor, and the other end of the measurement resistor is grounded, and the method includes:

acquiring a first leakage current measured by a first leakage current sensor and a second leakage current measured by a second leakage current sensor; the first leakage current sensor is respectively connected with the power supply positive terminal interface and the central point, and the second leakage current sensor is respectively connected with the power supply negative terminal interface and the central point;

and obtaining the high-voltage insulation state condition of the high-voltage power supply loop according to the first leakage current and the second leakage current.

In one embodiment, the method for detecting insulation of a high-voltage power supply loop of an automobile further comprises:

acquiring a third leakage current measured by a third leakage current sensor; the third leakage current sensor is connected with the power supply positive terminal interface and the power supply negative terminal interface respectively;

And obtaining the high-voltage insulation state condition of the high-voltage power supply loop according to the first leakage current, the second leakage current and the third leakage current.

In one embodiment, the obtaining the high voltage insulation state of the high voltage power supply loop according to the first leakage current and the second leakage current includes:

and when the first leakage current is not equal to zero or the second leakage current is not equal to zero, judging that the high-voltage insulation abnormality exists in the internal circuit of the high-voltage power supply loop.

In one embodiment, the obtaining the high voltage insulation state of the high voltage power supply loop according to the first leakage current, the second leakage current and the third leakage current includes:

and under the condition that the first leakage current and the second leakage current are respectively equal to zero, judging that the external circuit of the high-voltage power supply loop has high-voltage insulation abnormality when the third leakage current is not equal to zero.

In one embodiment, when the first leakage current is not equal to zero or the second leakage current is not equal to zero, the determining that the internal circuit of the high-voltage power supply circuit has a high-voltage insulation abnormality includes:

after a first external power supply switch connected to the power supply positive terminal interface and a second external power supply switch connected to the power supply negative terminal interface are respectively disconnected, judging that the internal circuit of the high-voltage power supply loop has high-voltage insulation abnormality when the first leakage current is not equal to zero or the second leakage current is not equal to zero; or alternatively, the first and second heat exchangers may be,

After a first pair of external power supply switches connected to the power supply positive terminal interface and a second pair of external power supply switches connected to the power supply negative terminal interface are respectively closed, when the first leakage current is not equal to zero or the second leakage current is not equal to zero, judging that the internal circuit of the high-voltage power supply loop has high-voltage insulation abnormality.

when the first leakage current is not equal to zero, judging that the high-voltage insulation of the internal circuit of the high-voltage power supply circuit is abnormal, and judging that the circuit between the power supply positive terminal interface and the central point of the high-voltage power supply circuit has the high-voltage insulation abnormality; or alternatively, the first and second heat exchangers may be,

and when the second leakage current is not equal to zero, judging that the high-voltage insulation of the internal circuit of the high-voltage power supply circuit is abnormal, and judging that the circuit between the power supply negative terminal interface and the central point of the high-voltage power supply circuit is abnormal.

In one embodiment, the power battery pack includes a first battery pack and a second battery pack; the positive electrode of the first battery pack is connected with the power supply positive electrode port, the negative electrode of the first battery pack is connected with the positive electrode of the second battery pack, and the negative electrode of the second battery pack is connected with the power supply negative electrode port; the connection point between the negative electrode of the first battery pack and the positive electrode of the second battery pack is the center point;

The insulation detection method of the automobile high-voltage power supply loop further comprises the following steps:

after judging that a high-voltage insulation abnormality exists in a circuit between the power supply positive terminal interface and the central point of the high-voltage power supply loop, calculating a first insulation resistance according to the voltage of the measuring resistor, the voltage of the first battery pack and the first leakage current; or alternatively, the first and second heat exchangers may be,

and after judging that the high-voltage insulation abnormality exists in the circuit between the power supply negative terminal interface and the central point, calculating a second insulation resistance according to the voltage of the measuring resistor, the voltage of the second battery pack and the second leakage current.

In one embodiment, when the first leakage current and the second leakage current are equal to zero, and the third leakage current is not equal to zero, the determining that the external line of the high-voltage power supply circuit has the high-voltage insulation abnormality includes:

when a first external power supply switch connected to the power supply positive terminal interface is closed and a second external power supply switch connected to the power supply negative terminal interface is opened, or when a first external power supply switch connected to the power supply positive terminal interface is opened and a second external power supply switch connected to the power supply negative terminal interface is closed and the first leakage current and the second leakage current are respectively equal to zero, judging that the external circuit of the high-voltage power supply loop has high-voltage insulation abnormality when the third leakage current is not equal to zero; or alternatively, the first and second heat exchangers may be,

After a first external power supply switch connected to the power supply positive terminal interface and a second external power supply switch connected to the power supply negative terminal interface are respectively closed, and under the condition that the first leakage current and the second leakage current are respectively equal to zero, when the third leakage current is not equal to zero, judging that the external circuit of the high-voltage power supply loop has high-voltage insulation abnormality.

and when the first leakage current and the second leakage current are respectively equal to zero, judging that the external circuit connected with the power supply positive electrode interface in the high-voltage power supply loop is abnormal in high-voltage insulation or the external circuit connected with the power supply negative electrode interface in the high-voltage power supply loop is abnormal in high-voltage insulation according to the positive and negative values of the third leakage current when the third leakage current is not equal to zero.

after judging that the high-voltage insulation abnormality exists in an external circuit connected with the power supply positive electrode port in the high-voltage power supply loop, calculating a third insulation resistance according to the voltage of the measuring resistor, the voltage of the first battery pack and the third leakage current; or alternatively, the first and second heat exchangers may be,

and after judging that the high-voltage insulation abnormality exists in an external circuit connected with the power supply negative electrode interface in the high-voltage power supply loop, calculating a fourth insulation resistance according to the voltage of the measuring resistor, the voltage of the second battery pack and the third leakage current.

The application second aspect provides an insulating detection circuitry of car high voltage power supply return circuit, the high voltage power supply return circuit includes power supply positive terminal interface, power battery group and power supply negative terminal interface, power battery group's both ends electrode respectively with power supply positive terminal interface reaches power supply negative terminal interface connection, insulating detection circuitry includes: the device comprises a measuring resistor, a first leakage current sensor, a second leakage current sensor and a signal measuring module;

one end of the measuring resistor is connected with the central point of the power battery pack, and the other end of the measuring resistor is grounded;

The first leakage current sensor is connected with the power supply positive terminal interface and the central point respectively;

the second leakage current sensor is connected with the power supply negative terminal interface and the central point respectively;

the signal measuring module is respectively connected with the measuring resistor, the first leakage current sensor and the second leakage current sensor; the signal measurement module is configured to perform the method as described above.

In one embodiment, the high-voltage power supply circuit insulation detection circuit of the automobile further comprises a third leakage current sensor, wherein the third leakage current sensor is connected with the power supply positive terminal interface and the power supply negative terminal interface respectively;

the signal measurement module is also connected with the third leakage current sensor.

In one embodiment, the high-voltage power supply loop insulation detection circuit of the automobile further comprises a measurement switch, and the measurement resistor is connected with the central point of the power battery pack through the measurement switch;

the signal measurement module is also used for controlling the closing and opening of the measurement switch.

A third aspect of the present application provides an insulation detection system for a high-voltage power supply circuit of an automobile, comprising: a high voltage supply loop and a circuit as described above;

The high-voltage power supply loop comprises a power supply positive terminal interface, a power battery pack and a power supply negative terminal interface, and two end electrodes of the power battery pack are respectively connected with the power supply positive terminal interface and the power supply negative terminal interface.

A fourth aspect of the present application provides an automobile comprising: a system as described above.

A fifth aspect of the present application provides an electronic device, comprising:

a processor; and

a memory having executable code stored thereon which, when executed by the processor, causes the processor to perform the method as described above.

A sixth aspect of the present application provides a computer readable storage medium having stored thereon executable code which, when executed by a processor of an electronic device, causes the processor to perform the method as described above.

The technical scheme that this application provided can include following beneficial effect:

according to the method, the first leakage current measured by the first leakage current sensor and the second leakage current measured by the second leakage current sensor are obtained, so that the high-voltage insulation state condition of the high-voltage power supply loop is obtained according to the first leakage current and the second leakage current. Therefore, the high-voltage power supply circuit can be subjected to high-voltage insulation state detection without injecting detection signals, and the normal operation of the high-voltage power supply circuit can be ensured.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The foregoing and other objects, features and advantages of the application will be apparent from the following more particular descriptions of exemplary embodiments of the application as illustrated in the accompanying drawings wherein like reference numbers generally represent like parts throughout the exemplary embodiments of the application.

Fig. 1 is a schematic flow chart of an insulation detection method of an automotive high-voltage power supply loop according to an embodiment of the present application;

FIG. 2 is another schematic flow chart of an insulation detection method for an automotive high-voltage power supply loop according to an embodiment of the present disclosure;

FIG. 3 is another schematic flow chart of an insulation detection method for an automotive high-voltage power supply loop according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of an insulation detection system of an automotive high-voltage power supply circuit according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of an insulation detection circuit of an automotive high-voltage power supply circuit according to an embodiment of the present application;

FIG. 6 is another schematic structural diagram of an insulation detection system for an automotive high voltage power supply loop according to an embodiment of the present disclosure;

fig. 7 is a schematic structural view of an automobile shown in an embodiment of the present application;

Fig. 8 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

Embodiments of the present application will be described in more detail below with reference to the accompanying drawings. While embodiments of the present application are shown in the drawings, it should be understood that the present application may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used in this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.

It should be understood that although the terms "first," "second," "third," etc. may be used herein to describe various information, these information should not be limited by these terms. These terms are only used to distinguish one type of information from another. For example, a first message may also be referred to as a second message, and similarly, a second message may also be referred to as a first message, without departing from the scope of the present application. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

The injection type insulation detection scheme in the related art can influence the operation of a high-voltage power supply loop and even cause safety risks.

According to the insulation detection method for the high-voltage power supply loop of the automobile, the high-voltage insulation state of the high-voltage power supply loop can be detected, detection signals are not required to be injected, and normal operation of the high-voltage power supply loop can be guaranteed.

The following describes the technical scheme of the embodiments of the present application in detail with reference to the accompanying drawings.

Fig. 1 is a schematic flow chart of an insulation detection method for an automotive high-voltage power supply circuit according to an embodiment of the present application. The high-voltage power supply circuit of the embodiment of fig. 1 may include a power supply positive terminal interface, a power battery pack, and a power supply negative terminal interface, where two end electrodes of the power battery pack are connected to the power supply positive terminal interface and the power supply negative terminal interface, respectively, and a center point of the power battery pack is connected to one end of the measuring resistor, and the other end of the measuring resistor is grounded.

Referring to fig. 1, the method includes:

step S101, obtaining a first leakage current measured by the first leakage current sensor and a second leakage current measured by the second leakage current sensor.

The first leakage current sensor is connected with the power supply positive terminal interface and the center point respectively, and the second leakage current sensor is connected with the power supply negative terminal interface and the center point respectively.

The first leakage current sensor and the second leakage current sensor may be direct current leakage current sensors. The DC leakage current sensor is a measuring module which converts the DC current to be measured into a DC current or voltage signal which is output in proportion to the DC current by using the fluxgate principle.

The direct current leakage current sensor is used for being circumferentially arranged on the positive outlet line and the negative outlet line of the direct current loop, when the insulation condition of the direct current loop is normal, the current flowing through the direct current leakage current sensor is equal in magnitude and opposite in direction, and the output signal value is zero; when the insulation condition of the direct current loop is abnormal (such as a ground short circuit), the direct current leakage current sensor has a differential current flowing through, and the output signal value of the direct current leakage current sensor is not zero.

In one embodiment, the power battery pack comprises a first battery pack and a second battery pack; the positive electrode of the first battery pack is connected with the power supply positive electrode port, the negative electrode of the first battery pack is connected with the positive electrode of the second battery pack, and the negative electrode of the second battery pack is connected with the power supply negative electrode port; the connection point between the negative electrode of the first battery and the positive electrode of the second battery is the center point. Therefore, the first leakage current sensor can measure the first leakage current of the direct current loop where the first battery pack is located, and the second leakage current sensor can measure the second leakage current of the direct current loop where the second battery pack is located.

In this step, the obtained first leakage current may be a signal value output by the first leakage current sensor to the measurement result, and the obtained second leakage current may be a signal value output by the second leakage current sensor to the measurement result.

Step S102, obtaining the high-voltage insulation state condition of the high-voltage power supply loop according to the first leakage current and the second leakage current.

In one embodiment, when the first leakage current is not equal to zero or the second leakage current is not equal to zero, it is determined that the internal circuit of the high-voltage power supply circuit has a high-voltage insulation abnormality. That is, when the first leakage current is not equal to zero or the second leakage current is not equal to zero, it is indicated that the high-voltage insulation abnormality exists in the line between the power supply positive terminal interface and the power supply negative terminal interface in the high-voltage power supply loop.

Fig. 2 is another flow chart of an insulation detection method for a high-voltage power supply loop of an automobile according to an embodiment of the application. Fig. 2 illustrates the solution of the present application in more detail with respect to fig. 1. The high-voltage power supply circuit of the embodiment of fig. 2 may include a power supply positive terminal interface, a power battery pack, and a power supply negative terminal interface, where two terminal electrodes of the power battery pack are connected to the power supply positive terminal interface and the power supply negative terminal interface, respectively, and a center point of the power battery pack is connected to one terminal of the measuring resistor, and the other terminal of the measuring resistor is grounded.

Referring to fig. 2, the method includes:

step S201, obtain the first leakage current measured by the first leakage current sensor and the second leakage current measured by the second leakage current sensor.

This step may be described in step S101, and will not be described here.

Step S202, obtaining the high-voltage insulation state condition of the high-voltage power supply loop according to the first leakage current and the second leakage current.

This step may be described in step S102, and will not be described here.

Step S203, obtaining the third leakage current measured by the third leakage current sensor.

The third leakage current sensor is connected with the power supply positive terminal interface and the power supply negative terminal interface respectively. The third leakage current sensor can be a direct current leakage current sensor, and the second leakage current sensor can measure the third leakage current of the direct current loop where the power battery pack is located.

In this step, the obtained third leakage current may be a signal value output from the third leakage current sensor to the measurement result.

Step S204, obtaining the high voltage insulation state of the high voltage power supply loop according to the first leakage current, the second leakage current and the third leakage current.

In one embodiment, when the first leakage current and the second leakage current are respectively equal to zero and the third leakage current is not equal to zero, it is determined that the external line of the high-voltage power supply circuit has a high-voltage insulation abnormality. That is, it can be determined that there is a high-voltage insulation abnormality in the external line connected to the power supply positive terminal interface in the high-voltage power supply circuit or that there is a high-voltage insulation abnormality in the external line connected to the power supply negative terminal interface in the high-voltage power supply circuit.

As can be seen from this embodiment, in the method provided in this embodiment of the present application, the first leakage current measured by the first leakage current sensor, the second leakage current measured by the second leakage current sensor, and the third leakage current measured by the third leakage current sensor are obtained, so that the high-voltage insulation state condition of the high-voltage power supply loop is obtained according to the first leakage current, the second leakage current, and the third leakage current. Therefore, the high-voltage power supply circuit can be subjected to high-voltage insulation state detection without injecting detection signals, and the normal operation of the high-voltage power supply circuit can be ensured.

Fig. 3 is another flow chart of an insulation detection method for a high-voltage power supply loop of an automobile according to an embodiment of the application. Fig. 3 illustrates the solution of the present application in more detail with respect to fig. 2. The high-voltage power supply circuit of the embodiment of fig. 3 may include a power supply positive terminal interface, a power battery pack, and a power supply negative terminal interface, where two terminal electrodes of the power battery pack are connected to the power supply positive terminal interface and the power supply negative terminal interface, respectively, and a center point of the power battery pack is connected to one terminal of the measuring resistor, and the other terminal of the measuring resistor is grounded.

Referring to fig. 3, the method includes:

step S301, obtain a first leakage current measured by the first leakage current sensor, a second leakage current measured by the second leakage current sensor, and a third leakage current measured by the third leakage current sensor.

This step may refer to the descriptions in step S201 and step S203, and will not be described here again.

Further, referring to fig. 4, in the embodiment of fig. 3, the power battery pack includes a first battery pack B1 and a second battery pack B2. The positive electrode of the first battery pack B1 is connected with a power supply positive electrode terminal interface B+, the negative electrode of the first battery pack B1 is connected with the positive electrode of the second battery pack B2, and the negative electrode of the second battery pack B2 is connected with a power supply negative electrode terminal interface B-; the connection point between the negative electrode of the first battery B1 and the positive electrode of the second battery B2 is the center point M.

The high voltage line between the positive electrode terminal interface b+ of the power supply and the positive electrode of the first battery B1 is a first cable Z1, the high voltage line between the negative electrode of the second battery B2 and the negative electrode terminal interface B-of the power supply is a second cable Z2, the high voltage line between the negative electrode of the first battery B1 and the center point M is a third cable Z3, and the high voltage line between the center point M and the positive electrode of the second battery B2 is a fourth cable Z4.

In the example shown in fig. 4, the first leakage current IL1 measured by the first leakage current sensor L1 is equal to the difference between the current I1 in the first cable Z1 and the current I3 in the third cable Z3, and in one embodiment, the first leakage current il1=i1-I3. The first leakage current sensor L1 may be installed between the first cable Z1 and the third cable Z3.

The second leakage current IL2 measured by the second leakage current sensor L2 is equal to the difference between the current I2 in the second cable Z2 and the current I4 in the fourth cable Z4, and in one embodiment, the second leakage current il2=i2-I4. The second leakage current sensor L2 may be installed between the second cable Z2 and the fourth cable Z4.

The third leakage current IL3 measured by the third leakage current sensor L3 is equal to the difference between the current I2 in the second cable Z2 and the current I1 in the first cable Z1, and in one embodiment, the third leakage current il3=i2-I1. The third leakage current sensor L3 may be installed between the first and second cables Z1 and Z2.

Step S302, after the first pair of external power supply switches connected to the power supply positive terminal interface and the second pair of external power supply switches connected to the power supply negative terminal interface are respectively disconnected, when the first leakage current is not equal to zero or the second leakage current is not equal to zero, it is determined that the internal circuit of the high-voltage power supply circuit has a high-voltage insulation abnormality.

It should be noted that, in the embodiment shown in fig. 4, the power supply positive terminal interface b+ is connected to the first pair of external power supply switches (not shown), the power supply negative terminal interface B-is connected to the second pair of external power supply switches (not shown), the power supply positive terminal interface b+ and the power supply negative terminal interface B-are connected to the load device (e.g. the driving motor) through the first pair of external power supply switches and the second pair of external power supply switches, and the power battery pack will supply power to the load device when the first pair of external power supply switches and the second pair of external power supply switches are closed respectively. When the first pair of external power supply switches and the second pair of external power supply switches are respectively disconnected, that is, the high-voltage power supply loop where the power battery pack is located does not supply power outwards. The high voltage supply loop may be insulation tested before it is powered outwards. Before the high-voltage power supply loop supplies power outwards, the insulation detection of the high-voltage power supply loop is achieved by executing the step 302, the insulation problem of the high-voltage power supply loop is found in time, and the situation that insulation abnormality occurs in the outwards power supply process and safety is affected is avoided.

In one embodiment, when the first leakage current is not equal to zero or the second leakage current is not equal to zero, the determining that the internal circuit of the high-voltage power supply circuit has the high-voltage insulation abnormality may include:

in step S302-1, when the first leakage current is not equal to zero, it is determined that the high voltage insulation abnormality exists in the line between the power supply positive terminal interface and the center point.

That is, the first leakage current il1+.0 indicates that the high voltage power supply circuit has a high voltage insulation abnormality in the line between the power supply positive terminal interface b+ and the center point M, i.e. a high voltage insulation abnormality point exists among the first cable Z1, the first battery B1 and the third cable Z3.

Further, in one embodiment, after determining that the high-voltage insulation abnormality exists in the line between the power supply positive terminal interface and the center point, the first insulation resistance may be calculated according to the voltage of the measurement resistor, the voltage of the first battery pack, and the first leakage current.

Since the center point M is the center point of the power battery pack, the third cable Z3 is short in length, and the first insulation resistance can be regarded as equivalent to the insulation resistance on the first cable Z1. First insulation resistance rp1= (ur+ub1)/IL 1. The UR is the voltage of the measuring resistor R, that is, the measured voltage UR can be obtained by measuring the voltage of the measuring resistor R. The voltage of the first battery of UB1, IL1 is the first leakage current.

Step S302-2, when the second leakage current is not equal to zero, it is determined that the high voltage insulation abnormality exists in the line between the power supply negative terminal interface and the center point.

That is, the second leakage current il2+.0 indicates that the high voltage power supply circuit has a high voltage insulation abnormality in the line between the power supply negative terminal interface B-and the center point M, i.e. a high voltage insulation abnormality point exists in the second cable Z2, the second battery pack B2 and the fourth cable Z4.

Further, in one embodiment, after determining that the high-voltage insulation abnormality exists in the line between the power supply negative terminal interface and the center point, the second insulation resistance may be calculated according to the voltage of the measurement resistor, the voltage of the second battery pack, and the second leakage current.

Since the center point M is the center point of the power battery pack, the fourth cable Z4 is short in length, and the second insulation resistance can be regarded as equivalent to the insulation resistance on the second cable Z2. Second insulation resistance r1= (ur+ub2)/IL 2. The UR is the voltage of the measuring resistor R, that is, the measured voltage UR can be obtained by measuring the voltage of the measuring resistor R. The voltage of the second battery of UB2, IL2 is the second leakage current.

It should be further noted that, when a two-point fault occurs (i.e., there is a high voltage insulation abnormality in the line between the power supply positive terminal interface b+ and the center point M, and there is a high voltage insulation abnormality in the line between the power supply negative terminal interface B-and the center point M), the first insulation resistance Rp1 and the second insulation resistance Rn1 may be calculated respectively.

It will be appreciated that the high voltage supply loop is normally insulated, and the load current of the power battery is I0, where i1=i2=i3=i4=i0, and thus il1=il2=il3=0, where the measurement voltage UR of the connected measurement resistor=0.

Before the high-voltage power supply loop supplies power outwards, that is, after the first pair of external power supply switches connected to the power supply positive terminal interface and the second pair of external power supply switches connected to the power supply negative terminal interface are respectively disconnected, when the first leakage current IL1 is equal to zero and the second leakage current IL2 is equal to zero, it can be judged that the internal circuit of the high-voltage power supply loop (that is, the circuit between the power supply positive terminal interface b+ and the power supply negative terminal interface B-) is insulated normally.

Step S303, when the first pair of external power supply switches connected to the power supply positive terminal interface is closed and the second pair of external power supply switches connected to the power supply negative terminal interface is opened, or the first pair of external power supply switches connected to the power supply positive terminal interface is opened and the second pair of external power supply switches connected to the power supply negative terminal interface is closed, and under the condition that the first leakage current and the second leakage current are respectively equal to zero, when the third leakage current is not equal to zero, it is determined that the external circuit of the high-voltage power supply circuit has a high-voltage insulation abnormality.

In one embodiment, when the first leakage current and the second leakage current are respectively equal to zero, and when the third leakage current is not equal to zero, it is determined that the external circuit connected with the power supply positive terminal interface in the high-voltage power supply loop has a high-voltage insulation abnormality or the external circuit connected with the power supply negative terminal interface in the high-voltage power supply loop has a high-voltage insulation abnormality according to the positive and negative value conditions of the third leakage current.

Further, step S303 may include step S303-1 and step S303-2.

In step S303-1, after the first external power supply switch connected to the power supply positive terminal interface is turned on and the second external power supply switch connected to the power supply negative terminal interface is turned off, when the first leakage current and the second leakage current are respectively equal to zero, and when the third leakage current is not equal to zero, it is determined that the external circuit connected to the power supply positive terminal interface in the high voltage power supply loop has a high voltage insulation abnormality according to the fact that the third leakage current is a negative value.

In the embodiment shown in fig. 4, after the first pair of external power switches connected to the power supply positive terminal interface b+ is closed and the second pair of external power switches connected to the power supply negative terminal interface B-is opened, i.e., the first pair of external power switches is closed, the second pair of external power switches is opened. That is, the high voltage power supply circuit where the power battery pack is located does not supply power to the outside. Before the high-voltage power supply loop supplies power outwards, the insulation detection of the high-voltage power supply loop is realized by executing the step 303-1, the insulation problem of the high-voltage power supply loop is found in time, and the situation that insulation abnormality occurs in the outwards power supply process and the safety is influenced is avoided.

In this step, il1=il2=0, the third leakage current IL3 is negative, and the third leakage current il3=ur/R. Where UR is the voltage of the measuring resistor R, UR is a negative value, and R is the resistance of the measuring resistor R. It is indicated that there is a high voltage insulation abnormality in the external line connected to the supply positive terminal interface b+ in the high voltage supply loop.

Further, in one embodiment, after determining that the external line connected to the power supply positive terminal interface b+ in the high-voltage power supply circuit has a high-voltage insulation abnormality, the third insulation resistance may be calculated according to the voltage of the measurement resistor, the voltage of the first battery pack, and the third leakage current.

The third insulation resistance is the insulation resistance of the external circuit connected with the power supply positive terminal interface b+ in the high-voltage power supply loop, and the third insulation resistance rp2= (ur+ub1)/IL 3. Where UR is the voltage of the measurement resistor R, i.e. the measurement voltage. The voltage of the first battery of UB1, IL3 is the third leakage current.

It can be understood that after the first external power supply switch connected to the power supply positive terminal interface b+ is closed and the second external power supply switch connected to the power supply negative terminal interface B-is opened, i.e. the first external power supply switch is closed, and after the second external power supply switch is opened, when the third leakage current IL3 is equal to zero, it is determined that the external circuit connected to the power supply positive terminal interface b+ in the high voltage power supply loop is insulated normally.

Step S303-2, after the first external power supply switch connected to the power supply positive terminal interface is opened and the second external power supply switch connected to the power supply negative terminal interface is closed, when the first leakage current and the second leakage current are respectively equal to zero, judging that the external circuit connected to the power supply negative terminal interface in the high-voltage power supply loop has abnormal high-voltage insulation according to the condition that the third leakage current is positive when the third leakage current is not equal to zero.

In the embodiment shown in fig. 4, after the first pair of external power switches connected to the power supply positive terminal interface b+ is opened and the second pair of external power switches connected to the power supply negative terminal interface B-is closed, that is, the first pair of external power switches is opened and the second pair of external power switches is closed. That is, the high voltage power supply circuit where the power battery pack is located does not supply power to the outside. Before the high-voltage power supply loop supplies power outwards, the insulation detection of the high-voltage power supply loop is realized by executing the step 303-2, the insulation problem of the high-voltage power supply loop is found in time, and the situation that insulation abnormality occurs in the outwards power supply process and the safety is influenced is avoided.

In this step, il1=il2=0, the third leakage current IL3 is a positive value, and the third leakage current il3=ur/R. Where UR is the voltage of the measuring resistor R, UR is a positive value, and R is the resistance of the measuring resistor R. It is indicated that there is a high voltage insulation abnormality in the external line connected to the supply negative terminal interface B-in the high voltage supply loop.

Further, in one embodiment, after determining that the external line connected to the power supply negative terminal interface in the high voltage power supply circuit has a high voltage insulation abnormality, the fourth insulation resistance may be calculated according to the voltage of the measurement resistor, the voltage of the second battery pack, and the third leakage current.

The fourth insulation resistance is the insulation resistance of an external circuit connected with the power supply negative terminal interface B-in the high-voltage power supply loop, and the fourth insulation resistance Rn2= (-UR+UB2)/IL 3. Where UR is the voltage of the measurement resistor R, i.e. the measurement voltage. The voltage of the second battery of UB2, IL3 is the third leakage current.

It can be understood that when the first external power supply switch connected to the power supply positive terminal interface b+ is opened and the second external power supply switch connected to the power supply negative terminal interface B-is closed, that is, the first external power supply switch is opened, and the second external power supply switch is closed, when the third leakage current IL3 is equal to zero, it is determined that the external circuit connected to the power supply negative terminal interface B-in the high voltage power supply loop is insulated normally.

It should be noted that, in the embodiment shown in fig. 4, when the first pair of external power supply switches and the second pair of external power supply switches are respectively closed, that is, the high voltage power supply circuit where the power battery pack is located is supplying power to the outside. In the process of externally supplying power to the high-voltage power supply circuit, the insulation detection of the high-voltage power supply circuit is realized by executing the step 304 and the step 305, and the insulation problem of the high-voltage power supply circuit is discovered in time.

Step S304, after the first pair of external power supply switches connected to the power supply positive terminal interface and the second pair of external power supply switches connected to the power supply negative terminal interface are respectively closed, when the first leakage current is not equal to zero or the second leakage current is not equal to zero, it is determined that the high-voltage insulation abnormality exists in the internal circuit of the high-voltage power supply loop.

step S304-1, when the first leakage current is not equal to zero, it is determined that the high-voltage insulation abnormality exists in the line between the power supply positive terminal interface and the center point, and the first insulation resistance is calculated according to the voltage of the measurement resistor, the voltage of the first battery pack and the first leakage current.

Step S304-2, when the second leakage current is not equal to zero, it is determined that the high-voltage insulation abnormality exists in the line between the power supply negative terminal interface and the center point of the high-voltage power supply loop, and the second insulation resistance is calculated according to the voltage of the measuring resistor, the voltage of the second battery pack and the second leakage current.

The description of step S304-1 may refer to step S302-1, and the description of step S304-2 may refer to step S302-2, which will not be repeated here.

In step S305, after the first pair of external power supply switches connected to the power supply positive terminal interface and the second pair of external power supply switches connected to the power supply negative terminal interface are respectively closed, and under the condition that the first leakage current and the second leakage current are respectively equal to zero, when the third leakage current is not equal to zero, it is determined that the external circuit of the high voltage power supply loop has a high voltage insulation abnormality.

In one embodiment, when the first leakage current and the second leakage current are respectively equal to zero and the third leakage current is not equal to zero, the determining that the external line of the high-voltage power supply loop has the high-voltage insulation abnormality may include:

in step S305-1, when the first leakage current and the second leakage current are respectively equal to zero, and when the third leakage current is not equal to zero, it is determined that the external circuit connected to the power supply positive terminal interface in the high-voltage power supply loop has a high-voltage insulation abnormality according to the negative value of the third leakage current, and the third insulation resistance is calculated according to the voltage of the measurement resistor, the voltage of the first battery pack and the third leakage current.

In step S305-2, when the first leakage current and the second leakage current are respectively equal to zero, and when the third leakage current is not equal to zero, it is determined that the external circuit connected to the power supply negative terminal interface in the high voltage power supply loop has a high voltage insulation abnormality according to the fact that the third leakage current is positive, and the fourth insulation resistance is calculated according to the voltage of the measurement resistor, the voltage of the second battery pack and the third leakage current.

The description of step S305-1 may refer to step S303-1, and the description of step S305-2 may refer to step S303-2, which will not be repeated here.

It can be understood that, in the case where the first pair of external power supply switches and the second pair of external power supply switches are respectively closed, that is, in the process of externally supplying power to the high-voltage power supply circuit, if a single point fault occurs (that is, an insulation fault exists in a line between the power supply positive terminal interface b+ and the center point M, a line between the power supply negative terminal interface B-and the center point M, an external line connected to the power supply positive terminal interface b+ or an external line connected to the power supply negative terminal interface B-, an insulation fault may be detected by executing step S304 or step S305). In addition, if a multipoint failure occurs, since the occurrence of failures at different positions is in chronological order, the positions of insulation abnormality can be detected separately. For example, when the first insulation resistance Rp1 and the second insulation resistance Rn1 exist simultaneously, the detection and calculation may be performed separately. However, when the third insulation resistance Rp2 and the fourth insulation resistance Rn2 coexist, the detection and calculation cannot be performed separately. The third insulation resistance Rp2 and the fourth insulation resistance Rn2 can be detected and calculated by executing step 302 and step S303 before the high voltage power supply circuit supplies power to the outside.

It should be further noted that, in view of the difficulty in completely avoiding the measurement error, in this application, zero may mean zero or close to zero, and close to zero may mean that the difference from zero is smaller than a preset value. For example, the first leakage current is equal to 0.1A, and if the preset value is 0.2A, the first leakage current is considered to be equal to zero.

Further, in one embodiment, one end of the measuring resistor R is connected to the center point M of the power battery pack through the measuring switch S, and the other end of the measuring resistor R is grounded through the body of the automobile. In this way, by controlling the closing and opening of the measuring switch S, it is controlled whether or not the high-voltage power supply circuit is insulated. By controlling the closing of the measuring switch S, insulation detection of the high voltage power supply circuit is performed. The insulation detection of the high-voltage power supply circuit is ended by controlling the measuring switch S to be turned off.

According to the method provided by the embodiment of the application, the high-voltage power supply loop can be subjected to high-voltage insulation state detection without injecting detection signals, so that the injection-free automobile high-voltage power supply loop insulation detection method is realized, and the normal operation of the high-voltage power supply loop can be ensured, namely the use of the high-voltage power supply loop and the state detection function of the high-voltage power supply loop are not influenced. Secondly, the insulation detection method is simple and reliable in steps. In addition, possess the ability of catching the unusual sudden change of insulation to high voltage power supply return circuit, can catch the unusual change of insulation of high voltage power supply return circuit, can confirm the position that takes place the insulation unusual and calculate corresponding insulation resistance value according to first leakage current, second leakage current and second leakage current that detects, insulation fault location is accurate, insulation detection precision is high, the performance is strong.

The application also provides an insulation detection circuit of the automobile high-voltage power supply loop.

Fig. 5 is a schematic structural diagram of an insulation detection circuit of an automotive high-voltage power supply circuit according to an embodiment of the present application.

Referring to fig. 4 and 5, an insulation detection circuit 50 of an automotive high-voltage power supply circuit is disclosed, wherein the high-voltage power supply circuit comprises a power supply positive terminal interface b+, a power battery pack and a power supply negative terminal interface B-, and two end electrodes of the power battery pack are respectively connected with the power supply positive terminal interface b+ and the power supply negative terminal interface B-. The power battery pack comprises a first battery pack B1 and a second battery pack B2. The positive electrode of the first battery pack B1 is connected with a power supply positive electrode terminal interface B+, the negative electrode of the first battery pack B1 is connected with the positive electrode of the second battery pack B2, and the negative electrode of the second battery pack B2 is connected with a power supply negative electrode terminal interface B-. The connection point between the negative electrode of the first battery B1 and the positive electrode of the second battery B2 is the center point M.

The automobile high-voltage power supply circuit insulation detection circuit 50 includes: the device comprises a measuring resistor R, a first leakage current sensor L1, a second leakage current sensor L2 and a signal measuring module 510.

One end of the measuring resistor R is connected with the center point M of the power battery pack, and the other end of the measuring resistor R is grounded.

The first leakage current sensor L1 is connected to the power supply positive terminal interface b+ and the center point M, respectively.

The second leakage current sensor L2 is respectively connected with the power supply negative terminal interface B-and the central point M.

The signal measurement module 510 is connected to the measurement resistor R, the first leakage current sensor L1, and the second leakage current sensor L2, respectively. The signal measurement module 510 is configured to perform the method of the embodiment of fig. 1-3.

As can be seen from this embodiment, the circuit 50 provided in this embodiment of the present application can detect the high-voltage insulation state of the high-voltage power supply circuit, and does not need to inject a detection signal, so that the normal operation of the high-voltage power supply circuit can be ensured.

Further, the insulation detection circuit 50 of the high-voltage power supply circuit of the automobile further includes a third leakage current sensor L3, and the third leakage current sensor L3 is connected to the power supply positive terminal interface b+ and the power supply negative terminal interface B-, respectively.

The signal measurement module 510 is also connected to a third leakage current sensor L3.

Further, the insulation detection circuit 50 of the high-voltage power supply circuit of the automobile further comprises a measurement switch S, and the measurement resistor R is connected with the center point M of the power battery pack through the measurement switch S.

The signal measurement module 510 is further configured to control on and off of the measurement switch S.

The application also provides an insulation detection system of the automobile high-voltage power supply loop.

Fig. 6 is a schematic structural diagram of an insulation detection system 60 of an automotive high-voltage power supply circuit according to an embodiment of the present application.

Referring to fig. 4 and fig. 6, an insulation detection system 60 for a high voltage power supply circuit of an automobile is characterized by comprising: the high voltage power supply loop 610 is insulated from the automotive high voltage power supply loop by a detection circuit 620.

The high-voltage power supply loop comprises a power supply positive terminal interface B+, a power battery pack and a power supply negative terminal interface B-, wherein two end electrodes of the power battery pack are respectively connected with the power supply positive terminal interface B+ and the power supply negative terminal interface B-.

Further, the power battery pack includes a first battery pack B1 and a second battery pack B2. The positive electrode of the first battery pack B1 is connected with a power supply positive electrode terminal interface B+, the negative electrode of the first battery pack B1 is connected with the positive electrode of the second battery pack B2, and the negative electrode of the second battery pack B2 is connected with a power supply negative electrode terminal interface B-. The connection point between the negative electrode of the first battery B1 and the positive electrode of the second battery B2 is the center point M.

The automotive high voltage supply loop insulation detection circuit 620 may be the circuit 50 as in the embodiment of fig. 5.

As can be seen from this embodiment, the system 60 provided in this embodiment of the present application can implement high-voltage insulation state detection on the high-voltage power supply circuit 610 through the automobile high-voltage power supply circuit insulation detection circuit 620, and does not need to inject a detection signal, so that normal operation of the high-voltage power supply circuit 610 can be ensured.

The application also provides an automobile.

Fig. 7 is a schematic structural view of an automobile shown in an embodiment of the present application.

Referring to fig. 7, an automobile 70 includes an automobile high voltage power supply loop insulation detection system 710.

The high-voltage power supply circuit insulation detection system 710 of the automobile can be the system 60 as shown in the embodiment of fig. 6.

As can be seen from this embodiment, the automobile 70 provided in the embodiment of the present application can implement high-voltage insulation state detection on the high-voltage power supply circuit through the automobile high-voltage power supply circuit insulation detection system 710, and does not need to inject a detection signal, so that normal operation of the high-voltage power supply circuit can be ensured.

Referring to fig. 8, an electronic device 800 includes a memory 810 and a processor 820.

Processor 820 may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), field programmable gate arrays (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

Memory 810 may include various types of storage units, such as system memory, read Only Memory (ROM), and persistent storage. Where the ROM may store static data or instructions that are required by the processor 820 or other modules of the computer. The persistent storage may be a readable and writable storage. The persistent storage may be a non-volatile memory device that does not lose stored instructions and data even after the computer is powered down. In some embodiments, the persistent storage device employs a mass storage device (e.g., magnetic or optical disk, flash memory) as the persistent storage device. In other embodiments, the persistent storage may be a removable storage device (e.g., diskette, optical drive). The system memory may be a read-write memory device or a volatile read-write memory device, such as dynamic random access memory. The system memory may store instructions and data that are required by some or all of the processors at runtime. Furthermore, memory 810 may include any combination of computer-readable storage media, including various types of semiconductor memory chips (e.g., DRAM, SRAM, SDRAM, flash memory, programmable read-only memory), magnetic disks, and/or optical disks may also be employed. In some implementations, memory 810 may include a readable and/or writable removable storage device such as a Compact Disc (CD), a digital versatile disc read only (e.g., DVD-ROM, dual layer DVD-ROM), a blu-ray read only disc, an ultra-dense disc, a flash memory card (e.g., SD card, min SD card, micro-SD card, etc.), a magnetic floppy disk, and the like. The computer readable storage medium does not contain a carrier wave or an instantaneous electronic signal transmitted by wireless or wired transmission.

The memory 810 has stored thereon executable code that, when processed by the processor 820, can cause the processor 820 to perform some or all of the methods described above.

Furthermore, the method according to the present application may also be implemented as a computer program or computer program product comprising computer program code instructions for performing part or all of the steps of the above-described method of the present application.

Alternatively, the present application may also be embodied as a computer-readable storage medium (or non-transitory machine-readable storage medium or machine-readable storage medium) having stored thereon executable code (or a computer program or computer instruction code) which, when executed by a processor of an electronic device (or a server, etc.), causes the processor to perform part or all of the steps of the above-described methods according to the present application.

The embodiments of the present application have been described above, the foregoing description is exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described. The terminology used herein was chosen in order to best explain the principles of the embodiments, the practical application, or the improvement of technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. The utility model provides an insulating detection method of car high voltage power supply return circuit, its characterized in that, high voltage power supply return circuit includes power supply positive terminal interface, power battery group and power supply negative terminal interface, power battery group's both ends electrode respectively with power supply positive terminal interface reaches power supply negative terminal interface connection, power battery group's central point is connected with measuring resistor one end, measuring resistor's the other end ground connection, the method includes:

obtaining a high-voltage insulation state condition of the high-voltage power supply loop according to the first leakage current and the second leakage current;

2. The method according to claim 1, wherein the obtaining the high voltage insulation state of the high voltage power supply loop according to the first leakage current and the second leakage current includes:

3. The method according to claim 1, wherein the obtaining the high voltage insulation state of the high voltage power supply loop according to the first leakage current, the second leakage current and the third leakage current includes:

4. The method according to claim 2, wherein the determining that the internal circuit of the high-voltage power supply circuit has the high-voltage insulation abnormality when the first leakage current is not equal to zero or the second leakage current is not equal to zero includes:

5. The method according to claim 2, wherein the determining that the internal circuit of the high-voltage power supply circuit has the high-voltage insulation abnormality when the first leakage current is not equal to zero or the second leakage current is not equal to zero includes:

6. The method according to claim 5, wherein: the power battery pack comprises a first battery pack and a second battery pack; the positive electrode of the first battery pack is connected with the power supply positive electrode port, the negative electrode of the first battery pack is connected with the positive electrode of the second battery pack, and the negative electrode of the second battery pack is connected with the power supply negative electrode port; the connection point between the negative electrode of the first battery pack and the positive electrode of the second battery pack is the center point;

The method further comprises the steps of:

7. The method according to claim 3, wherein when the third leakage current is not equal to zero in the case where the first leakage current and the second leakage current are equal to zero, determining that the external line of the high-voltage power supply circuit has a high-voltage insulation abnormality includes:

8. The method according to claim 3, wherein when the third leakage current is not equal to zero in the case where the first leakage current and the second leakage current are equal to zero, determining that the external line of the high-voltage power supply circuit has a high-voltage insulation abnormality includes:

9. The method according to claim 8, wherein: the power battery pack comprises a first battery pack and a second battery pack; the positive electrode of the first battery pack is connected with the power supply positive electrode port, the negative electrode of the first battery pack is connected with the positive electrode of the second battery pack, and the negative electrode of the second battery pack is connected with the power supply negative electrode port; the connection point between the negative electrode of the first battery pack and the positive electrode of the second battery pack is the center point;

The method further comprises the steps of:

10. The utility model provides an insulating detection circuitry of car high voltage power supply return circuit, its characterized in that, the high voltage power supply return circuit includes power supply positive terminal interface, power battery group and power supply negative terminal interface, power battery group's both ends electrode respectively with power supply positive terminal interface reaches power supply negative terminal interface connection, insulating detection circuitry includes: the device comprises a measuring resistor, a first leakage current sensor, a second leakage current sensor, a third leakage current sensor and a signal measuring module;

the third leakage current sensor is connected with the power supply positive terminal interface and the power supply negative terminal interface respectively;

the signal measuring module is respectively connected with the measuring resistor, the first leakage current sensor, the third leakage current sensor and the second leakage current sensor; the signal measurement module is configured to perform the method of any of claims 1-9.

11. The circuit of claim 10, wherein:

the circuit also comprises a measuring switch, and the measuring resistor is connected with the central point of the power battery pack through the measuring switch;

12. An insulation detection system for a high-voltage power supply loop of an automobile, comprising: a high voltage supply loop and a circuit as claimed in any one of claims 10 to 11;

13. An automobile, comprising: the system of claim 12.