A high-voltage battery insulation monitoring system for an electric vehicle

Abstract

The application discloses a high-voltage battery insulation monitoring system of an electric vehicle, which is arranged in a battery management system of the electric vehicle and comprises a power supply circuit, a single-chip microcomputer circuit, a communication circuit and a voltage acquisition circuit, wherein the power supply circuit is connected with the single-chip microcomputer circuit, the communication circuit and the voltage acquisition circuit, the single-chip microcomputer circuit is connected with the communication circuit and the voltage acquisition circuit, the voltage acquisition circuit is connected with an insulation resistance of a power battery pack and a contactor in parallel, the communication circuit is connected with a main module of the battery management system, the single-chip microcomputer circuit determines the resistance value of the insulation resistance of the power battery according to voltage data of the insulation resistance collected by the voltage acquisition circuit, and the resistance value is transmitted to the main module through the communication circuit, the main module monitors the resistance value of the insulation resistance of the power battery, and an alarm is given when the resistance value of the insulation resistance of the power battery is less than a set threshold value. The application can realize the monitoring of the insulation resistance and voltage of the battery and improve work efficiency.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle battery monitoring technology, and in particular to a high-voltage battery insulation monitoring system for electric vehicles. Background Technology

[0002] In the definition of vehicle-mounted energy storage devices, high-voltage battery systems belong to Class B voltage, with a maximum operating voltage >30VAC(RMS) and ≤1000VAC(RMS) or >60VDC and ≤1500VDC. The electrical safety of high-voltage battery systems is directly related to the life safety of system users. Insulation failure can cause direct harm to the human body from high voltage. Therefore, insulation resistance testing is an extremely important step.

[0003] Traditional testing circuits involve many components, including relays. If the testing circuit fails, it is necessary to check whether the components, including the relays, are faulty. However, components such as relays are fixed inside the enclosure. When the relays or other components fail, the enclosure must be removed. Removing the enclosure undoubtedly increases the workload and difficulty of testing, and greatly reduces work efficiency.

[0004] Therefore, a monitoring module is urgently needed to improve work efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a high-voltage battery insulation monitoring system for electric vehicles, which can monitor battery insulation resistance and voltage, improve work efficiency, and solve the above-mentioned problems existing in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] The present invention discloses a high-voltage battery insulation monitoring system for electric vehicles, wherein the high-voltage battery insulation monitoring system is installed in the battery management system of the electric vehicle, and the high-voltage battery insulation monitoring system includes a power supply circuit, a microcontroller circuit, a communication circuit, and a voltage acquisition circuit.

[0008] The power supply circuit is connected to the microcontroller circuit, the communication circuit, and the voltage acquisition circuit, respectively.

[0009] The microcontroller circuit is connected to the communication circuit and the voltage acquisition circuit, respectively.

[0010] The voltage acquisition circuit is connected in parallel with the insulation resistance and contactors of the power battery pack. The voltage acquisition circuit includes voltage acquisition units and voltage acquisition switches, with each voltage acquisition unit and voltage acquisition switch connected in a one-to-one correspondence. The microcontroller circuit is used to control the working state of the corresponding voltage acquisition unit through the voltage acquisition switch. The voltage acquisition unit is used to calculate the insulation resistance to determine the insulation performance, or to monitor the working state of the contactors in the battery pack. The working state of the contactor is the on / off state of the contactor. The voltage acquisition units for monitoring the working state of the contactors in the battery pack are located on the positive and negative contactors and on a contactor used to short-circuit a certain resistor.

[0011] The communication circuit is connected to the main module of the battery management system;

[0012] The microcontroller circuit is used to determine the insulation resistance value of the power battery based on the voltage data of the insulation resistance collected by the voltage acquisition circuit, and transmits the determined insulation resistance value of the power battery to the main module through the communication circuit to determine the insulation performance. The main module monitors the insulation resistance value of the power battery, and when the insulation resistance value of the power battery is less than a set threshold, it issues an alarm. The generated alarm information includes the battery pack identifier, and the alarm information reminds maintenance personnel to check and repair in a timely manner.

[0013] Furthermore, it also includes a connector circuit, through which the power supply circuit is connected to the microcontroller circuit, the communication circuit and the voltage acquisition circuit respectively. The connector circuit is used for voltage-current conversion and controlling the on / off state of the circuit.

[0014] Furthermore, the microcontroller circuit includes a program debugging unit and a microcontroller control unit. The program debugging unit is used to receive control commands from the host computer to edit the program of the microcontroller control unit.

[0015] Furthermore, the microcontroller circuit also includes an AD converter, which is connected to the voltage acquisition circuit and is used to convert the analog signal output by the voltage acquisition circuit into a digital signal.

[0016] Furthermore, there are four voltage acquisition units, and four corresponding voltage acquisition switches. One voltage acquisition unit is used to calculate the insulation resistance, and the other three voltage acquisition units are used to determine the state of the contactor.

[0017] Furthermore, the voltage acquisition unit is a voltage sensor.

[0018] Furthermore, the communication circuit is connected to the main module of the battery management system via a CAN bus.

[0019] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0020] The high-voltage battery insulation monitoring system for electric vehicles of this invention determines the insulation resistance value of the power battery by acquiring voltage data of the insulation resistance through a voltage acquisition circuit. Based on the determined insulation resistance value, the insulation performance is judged, and the operating status of the contactors in the battery pack is monitored, thereby improving the operational stability of the battery pack. This invention can replace physical testing, providing a clear and intuitive understanding of fault conditions. It reduces manual testing steps and eliminates the need for disassembly for inspection, significantly increasing work efficiency. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the high-voltage battery insulation monitoring system for electric vehicles according to the present invention.

[0023] Explanation of reference numerals in the attached diagram: 101, power supply circuit; 102, microcontroller circuit; 103, communication circuit; 104, voltage acquisition circuit. Detailed Implementation

[0024] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0025] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0026] like Figure 1 The diagram shown is a structural schematic of a high-voltage battery insulation monitoring system for an electric vehicle according to an embodiment of the present invention. The high-voltage battery insulation monitoring system for an electric vehicle according to an embodiment of the present invention is installed in the battery management system of the electric vehicle and includes a power supply circuit 101, a microcontroller circuit 102, a communication circuit 103 and a voltage acquisition circuit 104.

[0027] The power supply circuit 101 is connected to the microcontroller circuit 102, the communication circuit 103 and the voltage acquisition circuit 104 respectively.

[0028] The microcontroller circuit 102 is connected to the communication circuit 103 and the voltage acquisition circuit 104 respectively.

[0029] The voltage acquisition circuit 104 is connected in parallel with the insulation resistor and contactor of the power battery pack.

[0030] The communication circuit 103 is connected to the main module of the battery management system;

[0031] The microcontroller circuit 102 is used to determine the insulation resistance value of the power battery based on the voltage data of the insulation resistance collected by the voltage acquisition circuit 104, and transmit the determined insulation resistance value of the power battery to the main module through the communication circuit 103; the main module monitors the insulation resistance value of the power battery, and issues an alarm when the insulation resistance value of the power battery is less than a set threshold.

[0032] In this embodiment, the minimum insulation resistance requirements for electric vehicles specified in GB-T 18384-2015 are set as follows: 100Ω / V for DC and 500Ω / V for AC.

[0033] Furthermore, when the insulation resistance of the power battery is less than a set threshold, the generated alarm information includes the battery pack's identifier; the alarm information further alerts maintenance personnel to promptly inspect and repair the battery.

[0034] Specifically, the voltage acquisition circuit 104 includes a voltage acquisition unit and a voltage acquisition switch;

[0035] The voltage acquisition unit is connected to the voltage acquisition switch in a one-to-one correspondence; the microcontroller circuit 102 is also used to control the working state of the corresponding voltage acquisition unit through the voltage acquisition switch.

[0036] In one specific embodiment, the communication circuit 103 is connected to the main module of the battery management system via a CAN bus.

[0037] In a specific embodiment, there are four voltage acquisition units, corresponding to four voltage acquisition switches; one voltage acquisition unit is used to calculate the insulation resistance, and the other three voltage acquisition units are used to determine the contactor status. Determining the contactor status refers to whether the contactor is on or off. The three voltage acquisition units are located on the positive and negative contactors, and on the contactor used to short-circuit a certain resistor.

[0038] In this embodiment, the insulation performance is determined by setting a voltage acquisition unit to detect and calculate the insulation resistance of the battery to ground and the negative resistance to ground, and the working status of the contactor in the battery pack is monitored, thereby improving the working stability of the battery pack.

[0039] Optionally, the voltage acquisition unit is a voltage sensor.

[0040] To ensure circuit safety, the high-voltage battery insulation monitoring system for electric vehicles in this embodiment of the invention also includes a connector circuit.

[0041] The power supply circuit 101 is connected to the microcontroller circuit 102, the communication circuit 103 and the voltage acquisition circuit 104 respectively through a connector circuit;

[0042] The connector circuit is used for voltage and current conversion and for controlling the on / off state of the circuit.

[0043] In addition, the microcontroller circuit 102 includes a program debugging unit and a microcontroller control unit;

[0044] The program debugging unit is used to receive control commands from the host computer to edit the program of the microcontroller control unit.

[0045] The microcontroller circuit 102 also includes: an AD converter;

[0046] The AD converter is connected to the voltage acquisition circuit 104;

[0047] The AD converter is used to convert the analog signal output by the voltage acquisition circuit 104 into a digital signal.

[0048] The high-voltage battery insulation monitoring system for electric vehicles of the present invention can monitor the battery insulation resistance and voltage, thereby improving work efficiency.

[0049] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A high-voltage battery insulation monitoring system for electric vehicles, characterized in that, The high-voltage battery insulation monitoring system is installed in the battery management system of the electric vehicle. The high-voltage battery insulation monitoring system includes a power supply circuit, a microcontroller circuit, a communication circuit, and a voltage acquisition circuit. The power supply circuit is connected to the microcontroller circuit, the communication circuit, and the voltage acquisition circuit, respectively. The microcontroller circuit is connected to the communication circuit and the voltage acquisition circuit, respectively. The voltage acquisition circuit is connected in parallel with the insulation resistance and contactors of the power battery pack. The voltage acquisition circuit includes voltage acquisition units and voltage acquisition switches, with each voltage acquisition unit and voltage acquisition switch connected in a one-to-one correspondence. The microcontroller circuit is used to control the working state of the corresponding voltage acquisition unit through the voltage acquisition switch. The voltage acquisition unit is used to calculate the insulation resistance to determine the insulation performance, or to monitor the working state of the contactors in the battery pack. The working state of the contactor is the on / off state of the contactor. The voltage acquisition units for monitoring the working state of the contactors in the battery pack are located on the positive and negative contactors and on a contactor used to short-circuit a certain resistor. The communication circuit is connected to the main module of the battery management system; The microcontroller circuit is used to determine the insulation resistance value of the power battery based on the voltage data of the insulation resistance collected by the voltage acquisition circuit, and transmits the determined insulation resistance value of the power battery to the main module through the communication circuit to determine the insulation performance. The main module monitors the insulation resistance value of the power battery, and when the insulation resistance value of the power battery is less than a set threshold, it issues an alarm. The generated alarm information includes the battery pack identifier, and the alarm information reminds maintenance personnel to check and repair in a timely manner.

2. The high-voltage battery insulation monitoring system for electric vehicles according to claim 1, characterized in that, It also includes a connector circuit, through which the power supply circuit is connected to the microcontroller circuit, the communication circuit and the voltage acquisition circuit respectively. The connector circuit is used for voltage-current conversion and controlling the on / off state of the circuit.

3. The high-voltage battery insulation monitoring system for electric vehicles according to claim 1, characterized in that, The microcontroller circuit includes a program debugging unit and a microcontroller control unit. The program debugging unit is used to receive control commands from the host computer to edit the program of the microcontroller control unit.

4. The high-voltage battery insulation monitoring system for electric vehicles according to claim 3, characterized in that, The microcontroller circuit also includes an AD converter, which is connected to the voltage acquisition circuit and is used to convert the analog signal output by the voltage acquisition circuit into a digital signal.

5. The high-voltage battery insulation monitoring system for electric vehicles according to claim 1, characterized in that, There are four voltage acquisition units, and four corresponding voltage acquisition switches. One voltage acquisition unit is used to calculate the insulation resistance, and the other three voltage acquisition units are used to determine the status of the contactor.

6. The high-voltage battery insulation monitoring system for electric vehicles according to claim 1, characterized in that, The voltage acquisition unit is a voltage sensor.

7. A high-voltage battery insulation monitoring system for an electric vehicle according to any one of claims 1-6, characterized in that, The communication circuit is connected to the main module of the battery management system via a CAN bus.

Images