BMS test circuit

Abstract

The utility model provides a BMS test circuit, the BMS is connected with a power supply and an artificial load, the test circuit comprises a first switch circuit, a second switch circuit, a third switch circuit and a signal control circuit, the first switch circuit is used for connecting the output of the BMS and the positive electrode KL30 of the power supply; the second switch circuit is used for connecting the output of the BMS and the negative electrode KL31 of the power supply; the third switch circuit is used for connecting the output of the BMS and the input of the analog load; and the signal control circuit is used for outputting a trigger signal, controlling the on / off of each switching circuit, and realizing the short-circuit or open-circuit state of the BMS. The BMS test circuit provided by the utility model can automatically realize the open circuit and short circuit states of the BMS so as to test the BMS, so that personnel injury can be avoided, and the test efficiency can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electric vehicles, and particularly relates to a test circuit for a BMS. Background Art

[0002] The Battery Management System (BMS) is abbreviated as BMS. As the core system of an electric vehicle, the reliability and stability testing of the BMS system is particularly important. Usually, in the product detection link, short-circuit and open-circuit tests need to be carried out on the BMS.

[0003] Currently, when performing short-circuit and open-circuit tests on the BMS, experimenters need to manually disconnect the harness signal of the BMS or connect the signal to the positive power supply terminal KL30 and the negative power supply terminal KL31, which may cause problems such as personnel safety risks, accidental damage to products, and low test efficiency. Summary of the Utility Model

[0004] The purpose of the utility model is to solve the technical problems of personnel safety risks, accidental damage to products, and low test efficiency that are likely to occur when performing short-circuit and open-circuit tests on the BMS. The utility model provides a test circuit for a BMS, which can automatically realize the open-circuit and short-circuit states of the BMS to test the reliability and stability of the BMS. There is no need for personnel to manually disconnect or connect the harness, which can avoid personnel injuries, save manpower, and improve test efficiency.

[0005] An embodiment of the utility model provides a test circuit for a BMS. The BMS is connected to a power supply and an analog load. The test circuit includes:

[0006] A first switch circuit for connecting the output of the BMS and the positive terminal KL30 of the power supply;

[0007] A second switch circuit for connecting the output of the BMS and the negative terminal KL31 of the power supply;

[0008] A third switch circuit for connecting the output of the BMS and the input of the analog load;

[0009] A signal control circuit for outputting a trigger signal to control the disconnection or closure of each switch circuit to realize the short-circuit or open-circuit state of the BMS.

[0010] According to another specific embodiment of the utility model, the signal control circuit includes:

[0011] A controller for outputting a trigger signal;

[0012] A first conduction circuit, whose input end is connected to the controller and whose output end is connected to the first switch circuit;

[0013] A second conduction circuit, whose input terminal is connected to the controller and output terminal is connected to the second switch circuit;

[0014] A third conduction circuit, whose input terminal is connected to the controller and output terminal is connected to the third switch circuit;

[0015] Each conduction circuit is used to output a switching signal according to a trigger signal to control the opening or closing of each switch circuit.

[0016] According to another specific embodiment of the present invention, the controller is an MCU controller, and the MCU controller is used to output high and low level trigger signals. When each conduction circuit receives a high level signal, it outputs a switching signal to control the corresponding switch circuit to close; when each conduction circuit receives a low level signal, it outputs a switching signal to control the corresponding switch circuit to open.

[0017] According to another specific embodiment of the present invention,

[0018] The first switch circuit includes a first MOS transistor. The gate of the first MOS transistor is connected to the output terminal of the corresponding conduction circuit. The source of the first MOS transistor is connected to the positive pole KL30 of the power supply. The drain of the first MOS transistor is connected to the output of the BMS;

[0019] The second switch circuit includes a second MOS transistor. The gate of the second MOS transistor is connected to the output terminal of the corresponding conduction circuit. The source of the second MOS transistor is connected to the output of the BMS. The drain of the second MOS transistor is connected to the negative pole KL31 of the power supply;

[0020] The third switch circuit includes a third MOS transistor. The gate of the third MOS transistor is connected to the output terminal of the corresponding conduction circuit. The source of the third MOS transistor is connected to the output of the BMS. The drain of the third MOS transistor is connected to the input of the analog load.

[0021] According to another specific embodiment of the present invention, each conduction circuit includes a triode. The base of the triode is connected to the MCU controller. The collectors of the triodes in each conduction circuit are respectively connected to the gates of the MOS transistors in each switch circuit, and the emitter of the triode is grounded.

[0022] According to another specific embodiment of the present invention, each switch circuit further includes a first resistor, and the first resistor is connected in series between the gate and source of the corresponding MOS transistor.

[0023] According to another specific embodiment of the present invention, each switch circuit further includes a second resistor, and the second resistor is connected in series between the collector of the triode in the corresponding conduction circuit and the gate of the MOS transistor.

[0024] According to another specific embodiment of the present invention, each conduction circuit further includes:

[0025] The third resistor is connected in series between the base of the corresponding triode and the MCU controller;

[0026] The fourth resistor is connected in series between the base and the emitter of the corresponding triode.

[0027] According to another specific embodiment of the present invention, the triode is of NPN type.

[0028] According to another specific embodiment of the present invention, the MOS transistor is of PMOS type.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] For the test circuit of the BMS of the present invention, by setting the first, second, and third switch circuits between the output of the BMS, the positive and negative poles of the power supply, and the input of the analog load, and outputting a trigger signal through the signal control circuit to control the opening or closing of each switch circuit, the short - circuit or open - circuit state of the BMS can be realized. When it is necessary to perform an open - circuit test on the BMS, the signal control circuit outputs a trigger signal to control all three switch circuits to open, so as to realize the open - circuit state of the BMS. When it is necessary to perform a power - short - circuit test on the BMS, the signal control circuit outputs a trigger signal to control the first and third switch circuits to close, so as to realize the state of the BMS short - circuiting the power supply. When it is necessary to perform a ground - short - circuit test on the BMS, the signal control circuit outputs a trigger signal to control the second and third switch circuits to close, so as to realize the state of the BMS short - circuiting to the ground. The present invention can automatically realize the open - circuit and short - circuit states of the BMS to test the BMS, without the need for personnel to manually disconnect or connect the wire harness, which can avoid personal injury and improve the test efficiency. Description of the Drawings

[0031] Figure 1 Shows a schematic diagram of the test circuit of the BMS provided by an embodiment of the present invention;

[0032] Figure 2 Shows a schematic circuit diagram of the connection between the first switch circuit and the signal control circuit provided by an embodiment of the present invention;

[0033] Figure 3 Shows a schematic circuit diagram of the connection between the second switch circuit and the signal control circuit provided by an embodiment of the present invention;

[0034] Figure 4 Shows a schematic circuit diagram of the connection between the third switch circuit and the signal control circuit provided by an embodiment of the present invention.

[0035] Reference Numerals:

[0036] M1. The first MOS transistor; M2. The second MOS transistor; M3. The third MOS transistor; Q. The triode; R1. The first resistor; R2. The second resistor; R3. The third resistor; R4. The fourth resistor. Detailed implementation manners

[0037] The following specific embodiments illustrate the implementation manners of the present utility model. Those skilled in the art can easily understand other advantages and effects of the present utility model from the content disclosed in this specification. Although the description of the present utility model will be introduced in conjunction with the preferred embodiments, it does not mean that the features of this utility model are limited to this implementation manner. On the contrary, the purpose of introducing the utility model in conjunction with the implementation manner is to cover other alternatives or modifications that may be extended based on the claims of the present utility model. In order to provide a deep understanding of the present utility model, many specific details will be included in the following description. The present utility model can also be implemented without these details. In addition, in order to avoid confusing or obscuring the key points of the present utility model, some specific details will be omitted in the description. It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other.

[0038] It should be noted that in this specification, similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0039] The terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0040] Currently, when performing short - circuit and open - circuit tests on the BMS, experimenters need to manually disconnect the harness signal of the BMS or connect the signal to the positive power supply KL30 and the negative power supply KL31, which may cause problems such as personal safety risks, accidental damage to the product, and low test efficiency.

[0041] To solve the above - mentioned technical problems, the present utility model provides a test circuit for the BMS, which can automatically achieve the open - circuit and short - circuit states of the BMS to test the reliability and stability of the BMS. There is no need for personnel to manually disconnect or connect the harness, which can avoid personal injury and improve the test efficiency.

[0042] To make the technical solutions and advantages of the present utility model clearer, the embodiments of the present utility model will be further described in detail below.

[0043] Referring to Figure 1 , the implementation manner of the present utility model provides a test circuit for the BMS. The test circuit includes a first switch circuit, a second switch circuit, a third switch circuit, and a signal control circuit for controlling each switch circuit to be disconnected or closed ( Figure 1(not shown in the figure). Each output wire harness of the BMS is connected to the male connector P2 of the test circuit through the female connector P1. The male connector P2 of the test circuit is respectively connected to the first ends of the first, second, and third switch circuits. The second end of the first switch circuit is connected to the positive pole KL30 of the power supply. The second end of the second switch circuit is connected to the negative pole KL31 of the power supply. The second end of the third switch circuit is connected to the male connector P3 of the test circuit. Each input wire harness of the simulated load is connected to the female connector P4. P3 and P4 are connected so that the second end of the third switch circuit is connected to the input of the simulated load.

[0044] Exemplarily, referring to Figure 1 , in this embodiment, the BMS has 10 outputs, the corresponding simulated load also has 10 inputs, each connector also has 10 paths, and the three switch circuits also have 10 paths correspondingly. Among them, each first switch circuit includes switches SW1 to SW10, each second switch circuit includes switches SW21 to SW30, and each third switch circuit includes switches SW11 to SW20.

[0045] When an open-circuit test needs to be performed on the BMS, the signal control circuit outputs a trigger signal to control each switch circuit to be disconnected to achieve the open-circuit state of the BMS. At this time, it can be tested whether the BMS is safe and reliable in the open-circuit state.

[0046] When a short-circuit test needs to be performed on the BMS, two situations of the BMS short-circuit to the power supply and short-circuit to the ground can be tested respectively.

[0047] First, test the situation of the BMS short-circuit to the power supply. Make the signal control circuit output a trigger signal to control the third switch circuit to close, so that the output of the BMS is connected to the input of the simulated load. At this time, the output signal of the BMS is normally connected. Subsequently, make the signal control circuit control the first switch circuit to close, so that the BMS output is connected to KL30 to achieve the state of the BMS short-circuit to the power supply to detect whether the BMS is faulty. After the test is completed, the signal control circuit controls the first switch circuit to disconnect.

[0048] Second, test the situation of the BMS short-circuit to the ground. Make the signal control circuit output a trigger signal to control the second switch circuit to close, so that the BMS output is connected to KL31 to achieve the state of the BMS short-circuit to the ground to detect whether the BMS is faulty. After the test is completed, the signal control circuit controls the second switch circuit to disconnect again.

[0049] The utility model can automatically achieve the open-circuit and short-circuit states of the BMS to test the BMS, without manual disconnection or connection of the wire harness by personnel, which can avoid personal injury and improve the test efficiency.

[0050] Further, the signal control circuit includes a controller, a first conduction circuit, a second conduction circuit, and a third conduction circuit. The controller is configured to output a trigger signal. The input end of the first conduction circuit is connected to the controller, and the output end is connected to the first switch circuit. The input end of the second conduction circuit is connected to the controller, and the output end is connected to the second switch circuit. The input end of the third conduction circuit is connected to the controller, and the output end is connected to the third switch circuit. Each conduction circuit is configured to output a switching signal according to the trigger signal to control the opening or closing of each switch circuit.

[0051] According to an embodiment of the present application, the controller may be an MCU controller. The MCU controller is configured to output a high-low level trigger signal. When each conduction circuit receives a high-level signal, it outputs a switching signal to control the corresponding switch circuit to close; when each conduction circuit receives a low-level signal, it outputs a switching signal to control the corresponding switch circuit to open. When it is necessary to close the switch circuit, the MCU can output a high level, and when the conduction circuit receives the high-level signal, it controls the corresponding switch circuit to close. When it is necessary to open the switch circuit, the MCU can output a low level, and when the conduction circuit receives the low-level signal, it controls the corresponding switch circuit to open. Those skilled in the art can understand that the conduction control condition of the switch circuit can also be opposite to that of this embodiment. For example, when the MCU outputs a high level, it controls the switch circuit to open, and when the MCU outputs a low level, it controls the switch circuit to close. Similarly, those skilled in the art can understand that the MCU controller can also be composed of other circuit elements or conventional circuit structures. For example, a single-chip microcomputer can output a high-low level trigger signal to control the on-off of the switch circuit.

[0052] Next, in combination with Figures 2 to 4 the structure of the switch circuit and the signal control circuit of this embodiment will be further described. Figure 2 is a circuit schematic diagram of the connection between the first switch circuit and the signal control circuit. As Figure 2 shown, the first switch circuit includes a first MOS transistor M1, and the signal control circuit includes a triode Q as the first conduction circuit and an MCU controller (not shown in the figure). The base of Q is connected to the control pin of the MCU, the collector of Q is connected to the gate of M1, and the emitter of Q is grounded. The source of M1 is connected to the positive pole KL30 of the power supply, and the drain of M1 is connected to the output of the BMS. When the MCU outputs a high level, it controls Q to close to control M1 to close, that is, the first switch circuit closes, so that the output of the BMS is connected to KL30. When the MCU outputs a low level, it controls Q to open to control M1 to open, so that the first switch circuit opens. Figure 3 and Figure 4Circuit schematic diagrams showing the connection of the second switch circuit and the third switch circuit to the signal control circuit are respectively presented. Similar to the first switch circuit, when the MCU outputs a high level, it can control M2 or M3 to close, so that the second switch circuit or the third switch circuit is closed. When the MCU outputs a low level, it can control M2 or M3 to open, so that the second switch circuit or the third switch circuit is opened.

[0053] The circuit structure provided in this application is only one implementation manner. Those skilled in the art can understand that the switch circuit, conduction circuit, controller, etc. can also be composed of other circuit elements or conventional circuit structures.

[0054] Furthermore, referring to Figure 2 , the first switch circuit further includes a first resistor R1 and a second resistor R2. R1 is connected in series between the gate and source of M1, and R2 is connected in series between the collector of Q and the gate of M1. Referring to Figure 3 and Figure 4 , R1 and R2 are also provided in the second switch circuit and the third switch circuit, and they are respectively arranged in the corresponding circuits.

[0055] Furthermore, referring to Figure 2 , the first conduction circuit further includes a third resistor R3 and a fourth resistor R4. R3 is connected in series between the base of Q and the MCU controller, and R4 is connected in series between the base and emitter of Q. Referring to Figure 3 and Figure 4 , R3 and R4 are also provided in the second conduction circuit and the third conduction circuit, and they are respectively arranged in the corresponding circuits. R3 and R4 can form voltage-dividing resistors to set thresholds to prevent interference and avoid mis-turn-on and mis-turn-off of the triode Q.

[0056] Although the present invention has been illustrated and described by referring to some preferred embodiments of the present invention, those of ordinary skill in the art should understand that the above content is a further detailed description of the present invention in combination with specific embodiments, and it cannot be determined that the specific implementation of the present invention is only limited to these descriptions. Those skilled in the art can make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A test circuit for a BMS, characterized in that, The BMS is connected to a power supply and an analog load. The test circuit includes: A first switch circuit for connecting the output of the BMS and the positive pole KL30 of the power supply; A second switch circuit for connecting the output of the BMS and the negative pole KL31 of the power supply; A third switch circuit for connecting the output of the BMS and the input of the analog load; A signal control circuit for outputting a trigger signal to control the opening or closing of each of the switch circuits, thereby realizing the short - circuit or open - circuit state of the BMS.

2. The test circuit according to claim 1, wherein The signal control circuit includes: A controller for outputting the trigger signal; A first conduction circuit, whose input terminal is connected to the controller and output terminal is connected to the first switch circuit; A second conduction circuit, whose input terminal is connected to the controller and output terminal is connected to the second switch circuit; A third conduction circuit, whose input terminal is connected to the controller and output terminal is connected to the third switch circuit; Each of the conduction circuits is used to output a switch signal according to the trigger signal to control the opening or closing of each of the switch circuits.

3. The test circuit according to claim 2, wherein The controller is an MCU controller. The MCU controller is used to output high - and low - level trigger signals. When each of the conduction circuits receives a high - level signal, it outputs the switch signal to control the corresponding switch circuit to close; when each of the conduction circuits receives a low - level signal, it outputs the switch signal to control the corresponding switch circuit to open.

4. The test circuit according to claim 3, wherein The first switch circuit includes a first MOS transistor. The gate of the first MOS transistor is connected to the output terminal of the corresponding conduction circuit. The source of the first MOS transistor is connected to the positive pole KL30 of the power supply. The drain of the first MOS transistor is connected to the output of the BMS; The second switch circuit includes a second MOS transistor. The gate of the second MOS transistor is connected to the output terminal of the corresponding conduction circuit. The source of the second MOS transistor is connected to the output of the BMS. The drain of the second MOS transistor is connected to the negative pole KL31 of the power supply; The third switch circuit includes a third MOS transistor. The gate of the third MOS transistor is connected to the output terminal of the corresponding conduction circuit. The source of the third MOS transistor is connected to the output of the BMS. The drain of the third MOS transistor is connected to the input of the analog load.

5. The test circuit according to claim 4, wherein Each of the conduction circuits includes a triode. The base of the triode is connected to the MCU controller. The collectors of the triodes in each of the conduction circuits are respectively connected to the gates of the MOS transistors in each of the switch circuits. The emitter of the triode is grounded.

6. The test circuit according to claim 5, characterized in that, Each of the switch circuits further includes a first resistor, and the first resistor is connected in series between the gate and the source of the corresponding MOS transistor.

7. The test circuit according to claim 6, wherein Each of the switch circuits further includes a second resistor, and the second resistor is connected in series between the collector of the triode in the corresponding conduction circuit and the gate of the MOS transistor.

8. The test circuit according to claim 7, characterized in that, Each of the conduction circuits further includes: A third resistor connected in series between the base of the corresponding triode and the MCU controller; The fourth resistor is connected in series between the base and the emitter of the corresponding triode.

9. The test circuit according to claim 8, characterized in that, The triode is of NPN type.

10. The test circuit according to claim 9, wherein The MOS transistor is of PMOS type.

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