Battery test circuit and battery charging and discharging data acquisition circuit

Abstract

The utility model discloses a battery test circuit and a battery charge and discharge data acquisition circuit. The battery test circuit comprises an analog-to-digital conversion circuit, one end of which is connected with a high-speed processing assembly circuit, and the other end of which is connected with a digital control circuit; one end of the digital-to-analog conversion circuit is connected with the high-speed processing assembly circuit, and the other end of the digital-to-analog conversion circuit is connected with the digital control circuit; one end of the bidirectional power output circuit is connected with the digital control circuit, and the other end is connected with the battery pack to be tested; the number of the bidirectional power output circuits is multiple, each bidirectional power output circuit comprises a bidirectional power output circuit, each bidirectional power output circuit comprises a high-power low-dropout P-type SiC MOSFET and a special-shaped high-power low-dropout N-type MOSFET symmetrical to the high-power low-dropout P-type SiC MOSFET in characteristic parameter, the high-power low-dropout N-type MOSFET serves as an upper tube, the high-power low-dropout N-type MOSFET serves as a lower tube, and the special-shaped high-power low-dropout N-type MOSFET serves as a lower tube. And the high-power low-dropout P-type SiC MOSFET serves as a lower tube. The utility model can solve the problem of large error of equipment output signals.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery testing, and in particular to a battery testing circuit and a battery charge-discharge data acquisition circuit. BACKGROUND

[0002] At present, the main method of the new energy vehicle power battery health state detection system is to perform full charge-discharge cycling on the new energy vehicle battery, test the current capacity of the battery through the charge-discharge cycling, and compare it with the rated capacity to obtain the battery health state, i.e. SOH=(current capacity / rated capacity)*100%. However, this method needs to fully charge and discharge the battery, and it takes several hours to test once, and it takes several hours to test once. Some batteries take several hours to do a cycle, and the test efficiency is low.

[0003] At present, the test equipment mainly adopts various AC-DC type power electronic test equipment composed of IGBT power devices. This kind of equipment can realize large power density, small size and low cost, but since the power electronic devices work in switching state, it brings a lot of high-frequency switching noise to the equipment. This kind of switching noise is coupled to the output of the power supply through conduction, radiation and other ways, so that the output voltage and current have very many burrs, which greatly affects the precision of the power supply, resulting in poor test effect and affected test result accuracy. UTILITY MODEL CONTENT

[0004] The purpose of the utility model is to provide a battery testing circuit to at least solve one of the above technical problems.

[0005] The utility model provides the following scheme:

[0006] According to an aspect of the utility model, a battery testing circuit is provided, which comprises:

[0007] Analog-digital conversion circuit, one end of the analog-digital conversion circuit is connected with a high-speed processing component, and the other end is connected with the digital control circuit;

[0008] Digital-analog conversion circuit, one end of the digital-analog conversion circuit is connected with the high-speed processing component, and the other end is connected with the digital control circuit;

[0009] A bidirectional power output circuit, one end of each of the bidirectional power output circuits is connected with the digital control circuit, and the other end is connected with the battery pack to be tested; the number of the bidirectional power output circuits is multiple, each bidirectional power output circuit comprises a bidirectional power output circuit, the bidirectional power output circuit comprises a high-power low-dropout P-type SiC MOSFET and a special-shaped high-power low-dropout N-type MOSFET symmetrical to the characteristic parameters of the high-power low-dropout P-type SiC MOSFET, wherein the high-power low-dropout N-type MOSFET is used as an upper tube, and the high-power low-dropout P-type SiC MOSFET is used as a lower tube; wherein,

[0010] The high-speed processing component transmits an analog signal to an analog-to-digital conversion circuit in the high-performance test circuit and converts the analog signal into a digital signal to the digital control circuit, the digital control circuit generates a driving signal according to the obtained digital signal and transmits the driving signal to each bidirectional power output circuit to generate a voltage for the battery pack to be tested, and the voltage is output to the battery pack to be tested through the circuit.

[0011] The application also provides a battery charging and discharging data acquisition circuit, the battery charging and discharging data acquisition circuit comprising:

[0012] A high-speed processing component;

[0013] A battery test circuit, one end of the battery test circuit is connected with the high-speed processing component, and the other end of the battery test circuit is connected with the battery pack to be tested, and the battery test circuit is the battery test circuit as described above;

[0014] A data acquisition circuit, the data acquisition circuit is connected with the battery pack to be tested; wherein,

[0015] The high-speed processing component is used to send a control signal to the battery test circuit, so that the battery test circuit works;

[0016] The data acquisition circuit is used to collect data information in the charging and discharging process of the battery pack to be tested.

[0017] Optionally, the data acquisition circuit comprises:

[0018] A high-speed processing component, when the battery pack to be tested is a battery pack with a BMS, the high-speed processing component is used to read battery information collected by the BMS as data information.

[0019] Optionally, the data acquisition circuit further comprises:

[0020] A high-precision acquisition circuit, when the battery pack to be tested is a battery pack without a BMS, the high-precision acquisition circuit is used to collect battery information of the battery pack to be tested as data information.

[0021] Optionally, the high-precision acquisition circuit comprises:

[0022] a voltage and current sensor for acquiring voltage and current information of the battery pack under test during charging;

[0023] a conditioning circuit for converting the voltage and current information of the battery pack under test acquired by the voltage and current sensor into preset voltage level information;

[0024] an AD conversion circuit for converting the preset voltage level information transmitted by the conditioning circuit into digital information;

[0025] an isolation circuit through which the digital information is sent to the high-speed processing assembly.

[0026] Optionally, the battery charging and discharging data acquisition circuit further comprises:

[0027] a high-performance power supply circuit connected with the high-speed processing assembly circuit, the battery test circuit, and the data acquisition circuit respectively for supplying power to the high-speed processing assembly circuit, the battery test circuit, and the data acquisition circuit respectively.

[0028] The battery test circuit of the present application adopts high-performance SiC devices and works in a low-frequency range, thus no high-frequency switching noise in the prior art is generated. The design scheme makes the test voltage and current output by the device very clean, with a ripple less than 0.1V. The device can solve the large output signal error of the current technical device and improve the battery health state test precision. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a battery test circuit structure diagram in an embodiment of the present application;

[0030] Figure 2 is a whole structure diagram of a battery charging and discharging data acquisition circuit;

[0031] Figure 3 is an internal structure diagram of a high-speed processing assembly circuit;

[0032] Figure 4 is an internal structure diagram of a high-precision acquisition circuit;

[0033] Figure 5 is an internal structure diagram of a high-performance power supply circuit. DETAILED DESCRIPTION

[0034] The technical solutions of the utility model will be described clearly and completely in connection with the drawings below, obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the ordinary skilled in the art without making creative labor belong to the protection scope of the utility model.

[0035] Figure 1 It is the battery test circuit structure diagram in an embodiment of the application; Figure 2 It is the whole structure diagram of battery charge-discharge data acquisition circuit; Figure 3 It is the internal structure diagram of high-speed processing component circuit; Figure 4 It is the internal structure diagram of high-precision acquisition circuit; Figure 5 It is the internal structure diagram of high-performance power supply circuit.

[0036] As Figure 1 The battery test circuit shown in the figure includes analog-digital conversion circuit 2011, digital-analog conversion circuit 2012 and bidirectional power output circuit 2014, wherein,

[0037] One end of analog-digital conversion circuit 2011 is connected with high-speed processing component 202, and the other end is connected with digital control circuit 2013;

[0038] One end of digital-analog conversion circuit 2012 is connected with high-speed processing component 202, and the other end is connected with digital control circuit 2013;

[0039] One end of each bidirectional power output circuit 2014 is connected with digital control circuit, and the other end is connected with the battery pack to be tested; The number of bidirectional power output circuit 2014 is multiple, each bidirectional power output circuit 2014 includes a bidirectional power output circuit, the bidirectional power output circuit includes a high-power low-voltage difference P type SiC MOSFET and a special-shaped high-power low-voltage difference N type MOSFET symmetrical with the characteristic parameters of high-power low-voltage difference P type SiC MOSFET, wherein, the high-power low-voltage difference N type MOSFET is used as the upper tube, and the high-power low-voltage difference P type SiC MOSFET is used as the lower tube;

[0040] High-speed processing component 202 transmits analog signal to analog-digital conversion circuit 2011 in high-performance test circuit 201 and converts it into digital signal to digital control circuit 2013, digital control circuit 2013 generates driving signal according to the obtained digital signal and transmits it to each bidirectional power output circuit 2014 to generate voltage for the battery pack to be tested, and outputs to the battery pack to be tested through the circuit.

[0041] The battery test circuit of the application adopts high-performance SiC devices and makes the battery test circuit work in a low-frequency interval, so that high-frequency switching noise in the prior art is not generated, the design scheme makes the test voltage and current output by the device very clean, and the ripple is less than 0.1V, and the device can solve the large output signal error of the current technical device and improve the battery health state test precision.

[0042] Referring to Figures 2 to 5 The application also provides a battery charging and discharging data acquisition circuit, which comprises a high-speed processing component 202, a battery test circuit 201 and a data acquisition circuit, wherein,

[0043] One end of the battery test circuit is connected with the high-speed processing component 202, and the other end of the battery test circuit 201 is connected with a battery pack to be tested, and the battery test circuit 201 is the battery test circuit 201 as described above;

[0044] The data acquisition circuit is connected with the battery pack to be tested; wherein,

[0045] The high-speed processing component 202 is used for sending a control signal to the battery test circuit 201, so that the battery test circuit 201 works;

[0046] The data acquisition circuit is used for collecting data information in the charging and discharging process of the battery pack to be tested.

[0047] In the embodiment, when the battery pack to be tested is a battery pack with a BMS, the high-speed processing component 202 is used for reading battery information collected by the BMS as the data information.

[0048] In the embodiment, the data acquisition circuit further comprises a high-precision acquisition circuit 203, and when the battery pack to be tested is a battery pack without a BMS, the high-precision acquisition circuit 203 is used for collecting battery information of the battery pack to be tested as the data information.

[0049] In the embodiment, the high-precision acquisition circuit 203 comprises a voltage and current sensor 2031, a conditioning circuit 2032, an AD conversion circuit 2033 and an isolation circuit 2034, wherein,

[0050] The voltage and current sensor 2031 is used for collecting voltage information and current information of the battery pack to be tested in the charging process;

[0051] The conditioning circuit 2032 is used for converting the voltage information and current information of the battery pack to be tested collected by the voltage and current sensor 2031 into preset voltage level information;

[0052] The AD conversion circuit 2033 is used for converting the preset voltage level information transmitted by the conditioning circuit into digital information;

[0053] The digital information is sent to the high-speed processing component 202 after passing through the isolation circuit 2034.

[0054] In the embodiment, the battery charge and discharge data acquisition circuit further comprises a high-performance power supply circuit 204 connected with the high-speed processing component 202, the battery test circuit 201 and the data acquisition circuit respectively, for supplying power to the high-speed processing component 202, the battery test circuit 201 and the data acquisition circuit respectively.

[0055] The application will be further described in detail below, and it can be understood that the examples do not constitute any limitation on the application. Figures 1 to 5 The application can be further described in detail, and it can be understood that the examples do not constitute any limitation on the application.

[0056] Referring to Figures 1 to 5 , the application connects the total positive and total negative of the battery pack to the battery pack through the battery measurement circuit 201 to charge and discharge the battery pack. If the test object is a battery pack with BMS, the battery information collected by the BMS can be read through the high-speed processing component 202. If the test object is a module without BMS or a battery cell, the voltage, current, temperature and other signals of the battery during charging and discharging can be collected through the high-precision acquisition circuit 203 and the sensors distributed on the battery pack and sent to the high-speed processing component 202 for analysis and processing to generate the battery health state test result. The test result can generate a customized test report according to the demand. The entire test process only takes 10 minutes, greatly improving the efficiency of new energy vehicle battery health state test and evaluation.

[0057] Referring to Figure 1 , the battery test circuit 201 comprises an analog-digital conversion circuit 2011, a digital-analog conversion circuit 2012, a digital control circuit 2013 and a bidirectional power output circuit 2014.

[0058] The high-speed processing component 202 transmits the generated analog signal to the analog-to-digital conversion circuit 2011 in the battery test circuit 201 and converts it into a digital signal to the digital control circuit 2013, which generates a driving signal and transmits it to the bidirectional power output circuit 2014 to generate the voltage and current of the test battery device, and outputs it to the battery system being tested through the circuit. The output voltage is accurately collected by the voltage sensor in the loop, and the output current is accurately collected by the current sensor in the loop, and the collected values are transmitted to the digital control circuit 2013 for negative feedback operation, which can automatically and accurately adjust the output voltage and current signals, thereby greatly improving the precision and stability of the output signal. The large-power low-voltage difference P-type SiC MOSFET, the large-power low-voltage difference N-type MOSFET with the same characteristic parameters as the large-power low-voltage difference P-type SiC MOSFET, the large-power low-voltage difference N-type MOSFET as the upper tube, and the large-power low-voltage difference P-type SiC MOSFET as the lower tube, the gate and the emitter of the upper tube large-power low-voltage difference N-type MOSFET and the lower tube large-power low-voltage difference P-type SiC MOSFET are connected to each other to form a bidirectional power output circuit; SiC is used as a large-power device in a linear power amplifier to simplify the circuit structure and achieve higher power density output.

[0059] Referring to Figure 3 The high-speed processing component 202 includes: a high-speed processing component circuit 2021 that collects various signals for processing and generates various control signals, communication signals, and test signals; a voltage sensing circuit 2022 that acquires and transmits signals; and an isolation circuit 2023 that sends the signals to an external battery BMS system to interact with the battery information; and a high-performance power supply circuit 204 that supplies power to the isolation circuit 2023.

[0060] Referring to Figure 4 The high-precision acquisition circuit 203 converts various analog signals of different voltage levels and current sizes through a conditioning module 2032 to specific voltage levels, and then converts them to digital quantities through an A / D circuit 2033, and finally sends them to the high-speed processing component 202 through an isolation circuit 2034 for data analysis and operation.

[0061] Referring to Figure 5 In this embodiment, the high-performance power supply circuit 204 converts 220V AC voltage into various DC voltage levels through an internal AC-DC circuit to supply power to other modules.

[0062] The high-performance battery test circuit of the present application can avoid the high-frequency noise introduced by high-frequency switching in traditional test circuits, improve the accuracy of test signals, and improve the accuracy of new energy vehicle battery health testing.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery test circuit, characterized by, The battery test circuit comprises: an analog-digital conversion circuit (2011) connected at one end to a high-speed processing component (202) and at the other end to a digital control circuit (2013); a digital-analog conversion circuit (2012) connected at one end to the high-speed processing component (202) and at the other end to the digital control circuit (2013); a bidirectional power output circuit (2014) connected at one end to the digital control circuit and at the other end to a battery pack to be tested; the bidirectional power output circuit (2014) comprises a plurality of bidirectional power output circuits, each bidirectional power output circuit comprising a large-power low-voltage differential P-type SiC MOSFET and a large-power low-voltage differential N-type MOSFET symmetrical to the characteristic parameters of the large-power low-voltage differential P-type SiC MOSFET, wherein the large-power low-voltage differential N-type MOSFET serves as an upper tube and the large-power low-voltage differential P-type SiC MOSFET serves as a lower tube; and The high-speed processing component (202) transmits analog signals to the analog-digital conversion circuit (2011) in the high-performance test circuit (201) and converts them into digital signals to the digital control circuit (2013), which generates driving signals according to the digital signals obtained and transmits them to each bidirectional power output circuit (2014) to generate a voltage for the battery pack to be tested and output to the battery pack to be tested through the circuit.

2. A battery charge and discharge data acquisition circuit, characterized by comprising: The battery charge-discharge data acquisition circuit comprises: a high-speed processing component (202); a battery test circuit (201) connected at one end to the high-speed processing component (202) and at the other end to the battery pack to be tested, wherein the battery test circuit (201) is the battery test circuit (201) as claimed in claim 1; a data acquisition circuit connected to the battery pack to be tested; wherein The high-speed processing component (202) is configured to send a control signal to the battery test circuit (201) to make the battery test circuit (201) work. The data acquisition circuit is configured to collect data information in the charge-discharge process of the battery pack to be tested.

3. The battery charge and discharge data acquisition circuit according to claim 2, wherein When the battery pack to be tested is a battery pack with a BMS, the high-speed processing component (202) is configured to read battery information collected by the BMS as data information.

4. The battery charge and discharge data acquisition circuit according to claim 3, wherein The data acquisition circuit further comprises: a high-precision acquisition circuit (203) configured to collect battery information of the battery pack to be tested as data information when the battery pack to be tested is a battery pack without a BMS.

5. The battery charge and discharge data acquisition circuit of claim 4, wherein, The high-precision acquisition circuit (203) comprises: a voltage and current sensor (2031) configured to collect voltage information and current information of the battery pack to be tested in the charging process. The conditioning circuit (2032) is used for converting the voltage information and the current information of the battery pack to be tested collected by the voltage and current sensor (2031) into preset voltage level information; The AD conversion circuit (2033) is used for converting the preset voltage level information transmitted by the conditioning circuit into digital information; The isolation circuit (2034) is used for transmitting the digital information to the high-speed processing component (202) after the digital information passes through the isolation circuit (2034).

6. The battery charge and discharge data acquisition circuit of claim 5, wherein, The battery charging and discharging data acquisition circuit further comprises: The high-performance power supply circuit (204) is connected with the high-speed processing component (202), the battery test circuit (201) and the data acquisition circuit respectively, and is used for supplying power for the high-speed processing component (202), the battery test circuit (201) and the data acquisition circuit respectively.

Images