Power battery pack BMS low-voltage short-circuit power-on system
By using the low-voltage short-circuit power-on system of the power battery pack BMS, and controlling the circuit switching of the DC/DC converter using the power control board, the problems of excessive power consumption and safety hazards of traditional power-on methods are solved, and stable circuit operation and energy saving are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XIAN YUCHITENENG ELECTRONIC TECHNOLOGY CO LTD
- Filing Date
- 2025-07-15
- Publication Date
- 2026-05-29
Smart Images
Figure CN224305449U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of low-voltage power supply technology for power battery packs, specifically providing a low-voltage short-circuit power supply system for a power battery pack BMS. Background Technology
[0002] A Battery Management System (BMS) is a core electronic system that monitors, controls, and manages the operating status of a power battery pack, primarily used in electric vehicles and energy storage systems. Its core responsibility is to ensure the safe and efficient operation of the power battery pack and extend its lifespan.
[0003] Traditional power supply methods for battery packs, such as directly shorting the high-voltage terminal to power on the BMS, may consume excessive energy during system startup and certain operating modes, violating the low-power design principle of BMS. Furthermore, traditional power supply methods pose certain risks, as sudden high-voltage current can cause circuit instability, affecting normal equipment operation and potentially leading to safety accidents.
[0004] In addition, some circuit modules generate unnecessary static power consumption due to continuous power supply when the battery system is in standby or low-load conditions. Examples include the power consumption of the DC / DC converter in static mode and in sleep mode. Utility Model Content
[0005] This invention provides a low-voltage short-circuit power-on system for a power battery pack BMS, which solves the problems of excessive additional power consumption and potential dangers associated with traditional BMS power-on methods.
[0006] To address the aforementioned problems, this utility model provides a low-voltage short-circuit power-on system for a power battery pack BMS, comprising:
[0007] A battery module, which provides power to the high-voltage box, BMS module and power control board;
[0008] A high-voltage box, used to distribute the transmitted electrical energy;
[0009] A DC / DC converter is used to step down the power transmitted to the BMS module;
[0010] The BMS module is used to control the current switching of various components inside the high-voltage box and to monitor the working status of the battery module.
[0011] A power control board, which is used to control the current switching of the BMS module;
[0012] The positive terminal of the battery module is electrically connected to the high-voltage box and the first pin of the power control board, respectively, and the negative terminal of the battery module is electrically connected to the high-voltage box and the third pin of the power control board, respectively. The input terminal of the DC / DC converter is electrically connected to the positive terminal of the battery module, and the output terminal of the DC / DC converter is connected to the second pin of the power control board and the input terminal of the BMS module, respectively. The output terminal of the BMS module is electrically connected to the high-voltage box, and the BMS module is electrically connected to the battery module.
[0013] Furthermore, the power control board also includes: a step-down module, a first interface K1, a second interface K2, a current limiting module, a delay module, and a switching module, wherein:
[0014] The first pin is connected to K1 via a step-down module, which is used to reduce the voltage input to the first pin and transmit the reduced voltage to the first interface K1.
[0015] The second pin is connected to the second interface K2 through a current limiting module. The output of the current limiting module is grounded. The current limiting module is used to reduce the current of the second pin and ground it.
[0016] The second pin and the third pin are connected by a switch module, which is used to control the on / off state between the second pin and the third pin; the switch module is connected to the second interface K2 through a delay module, which is used to ensure that the switch module is turned on later than the current limiting module.
[0017] Furthermore, the step-down module includes a switching transistor MOS1, a first resistor R1, and a first diode D1, wherein the drain of the switching transistor MOS1 is connected to the first pin, the gate of the switching transistor MOS1 is connected in series with the first diode D1 and then grounded, and the source of the switching transistor MOS1 is connected to the first interface K1.
[0018] Furthermore, the current limiting module includes: a switching transistor MOS2 and a second resistor R2, wherein the source of the switching transistor MOS2 is grounded, the drain of the switching transistor MOS2 is connected to a second pin through the second resistor R2, and the gate of the switching transistor MOS2 is connected to a second interface K2.
[0019] Furthermore, the delay module includes a fifth resistor R5 and a Schmitt trigger S, wherein the second interface K2 is connected in series with the fifth resistor R5 and then connected to the input terminal of the Schmitt trigger S, and the output terminal of the Schmitt trigger S is electrically connected to the switching module.
[0020] Furthermore, the switching module includes: a switching transistor MOS3, the source of the switching transistor MOS3 is connected to the third pin, the drain of the switching transistor MOS3 is connected to the second pin, and the gate of the switching transistor MOS3 is connected to the output terminal of the Schmitt trigger S.
[0021] Furthermore, the current limiting module also includes a third resistor R3, one end of which is connected to the gate of the switching transistor MOS2, and the other end of which is grounded.
[0022] Furthermore, the delay module also includes a second diode D2, which is located between the fifth resistor R5 and the second interface K2. The positive terminal of the diode D2 is connected to the second interface K2, and the negative terminal of the second diode D2 is connected to the fifth resistor R5.
[0023] Furthermore, the switching module also includes a fourth resistor R4, one end of which is connected to the gate of the switching transistor MOS3, and the other end of which is grounded.
[0024] The power battery pack BMS low-voltage short-circuit power-on system provided by this utility model, by setting up a power control board, controls the circuit on and off of the DC / DC converter, realizing the function that the BMS module does not need to be directly connected to the high-voltage end during the power-on process, avoiding the problem of unstable circuit voltage. When power-on is not needed, the power-on circuit can be disconnected, reducing power consumption loss, saving energy, and thus extending the service life of the battery module.
[0025] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0026] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0027] Figure 1 This is a schematic diagram of the circuit connection relationship of the power battery pack BMS low-voltage short-circuit power-on system provided by this utility model.
[0028] Figure 2 This is a schematic diagram of the control principle of the power control board provided by this utility model.
[0029] Figure label:
[0030] 1. Battery module; 2. High voltage box; 3. DC / DC converter; 4. BMS module; 5. Power control board;
[0031] 501, First pin; 502, Second pin; 503, Third pin; 504, Step-down module; 505, Current limiting module; 506, Delay module; 507, Switch module. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0033] The following is combined with Figures 1 to 2 The embodiments shown illustrate the technical solution of this utility model:
[0034] This utility model embodiment provides a low-voltage short-circuit power-on system for a power battery pack BMS, such as... Figure 1 As shown, it includes a battery module 1, a high-voltage box 2, a DC / DC converter 3, a BMS module 4, and a power control board 5.
[0035] Among them: battery module 1 is used to provide power to high voltage box 2 and BMS module 4; high voltage box 2 is used to distribute the power transmitted from battery module 1; DC / DC converter 3 is used to step down the power transmitted to BMS module 4; power control board 5 is used to control the current of BMS module 4; BMS module 4 is used to control the current of each component inside high voltage box 2 and monitor the working status of battery module 1.
[0036] The positive terminal of battery module 1 is electrically connected to the high-voltage box 2 and the first pin 501 of the power control board 5, respectively. The negative terminal of battery module 1 is electrically connected to the high-voltage box 2 and the third pin 503 of the power control board 5, respectively. The input terminal of DC / DC converter 3 is electrically connected to the positive terminal of battery module 1. The output terminal of DC / DC converter 3 is connected to the second pin 502 of the power control board 5 and the input terminal of BMS module 4, respectively. The output terminal of BMS module 4 is electrically connected to the high-voltage box 2, and BMS module 4 is also electrically connected to battery module 1.
[0037] The low-voltage short-circuit power-on system of the battery pack BMS provided in this embodiment is powered by the battery module 1, which provides energy to the high-voltage box 2. By controlling the conduction and cutoff between the second pin 502 and the third pin 503 of the power control board 5, the circuit of the DC / DC converter 3 is controlled to provide the required power to the battery management system (BMS). After the BMS is powered on, it begins to perform its functions, monitoring key parameters such as voltage, current, temperature, and SOS of the battery module 1, while controlling the current flow of various components inside the high-voltage box 2. The core advantage of this system is that by controlling the power control board 5, the overall circuit can be switched on and off, thereby reducing unnecessary energy consumption.
[0038] In some implementations, reference Figure 2 The power control board 5 includes: a first pin 501, a second pin 502, a third pin 503, a step-down module 504, a first interface K1, a second interface K2, a current limiting module 505, a delay module 506, and a switch module 507. Specifically: the first pin 501 is connected to the first interface K1 via the step-down module 504, which reduces the voltage input to the first pin 501 and transmits the reduced voltage to the first interface K1; the second pin 502 is connected to the second interface K2 via the current limiting module 505, which... The output of the 505 timer is grounded. The current limiting module 505 limits the current to the second pin 502 and grounds it to prevent excessive instantaneous current from entering through the second pin 502 from damaging other devices. The second pin 502 and the third pin 503 are connected via a switch module 507, which controls the on / off state between them. The switch module 507 is connected to the second interface K2 via a delay module 506, which ensures that the switch module 507 is turned on later than the current limiting module 505. The total resistance of the current limiting module 505 is hundreds of times that of the switch module 507.
[0039] When power is required, the first interface K1 and the second interface K2 are shorted. The high-voltage current flowing into the first pin 501 is stepped down by the step-down module 504 and then flows to the current limiting module 505 and the delay module 506 respectively. The current limiting module 505 and the delay module 506 are turned on. The output current of the DC / DC converter 3 flows into the current limiting module 505 through the second pin 502 and is then grounded. After a period of time, the current output by the step-down module 504 is delayed by the delay module 506 and then flows into the switch module 507. The switch module 507 is turned on. Since the resistance of the switch module 507 is much smaller than the resistance of the current limiting module 505, the current limiting module 505 is short-circuited by the switch module 507. The current of the second pin 502 flows through the switch module 507 to the third pin 503 and finally to the negative terminal of the battery module 1. The entire circuit is turned on and power is started through the BMS module 4.
[0040] This embodiment of the utility model sets up a current limiting module 505. Initially, the current of the second pin 502 flows through the current limiting module 505 to ground. After the current and voltage stabilize, the switch module 507 is turned on through the delay module 506. This avoids damage to the switch module 507 caused by unstable voltage at the beginning, thus preventing safety issues.
[0041] In some examples, the step-down module 504 includes a switching transistor MOS1, a first resistor R1, and a first diode D1. The drain (D) of the switching transistor MOS1 is connected to the first pin 501, and the gate (G) of the switching transistor MOS1 is connected in series with the first diode D1 and grounded. The first diode D1 is used to control the voltage of the switching transistor MOS1 within a specified value. The first resistor R1 is connected between the drain of the switching transistor MOS1 and the first diode D1. The first resistor R1 plays a voltage stabilizing role and prevents the gate voltage of the switching transistor MOS1 from oscillating. The source (S) of the switching transistor MOS1 is connected to the first interface K1.
[0042] The high-voltage current input from the first pin 501 is reduced to a low-voltage current of about 15V by the step-down module 504. This low-voltage current is used to control the opening and closing of the current limiting module 505 and the switching module 507, thus preventing the high-voltage current from causing damage to the current limiting module 505 and the switching module 507.
[0043] In some examples, the current limiting module 505 includes: a switching transistor MOS2 and a second resistor R2, wherein the source of the switching transistor MOS2 is grounded, the drain of the switching transistor MOS2 is connected to the second pin 502 through the second resistor R2, and the gate of the switching transistor MOS2 is connected to the second interface K2.
[0044] In the current limiting module 505, the resistance of the second resistor R2 is hundreds of times that of the switch module 507. It can effectively cope with the instantaneous high voltage current that initially enters the second pin 502. The current limiting module 505 enters first, which can avoid the impact on the switch module 507 caused by the instantaneous high voltage current directly passing through the switch module 507, thereby ensuring the normal operation of the entire device.
[0045] In some examples, the delay module 506 includes a fifth resistor R5 and a Schmitt trigger S, wherein the second interface K2 is connected in series with the fifth resistor R5 and then connected to the input of the Schmitt trigger S, and the output of the Schmitt trigger S is electrically connected to the switch module 507.
[0046] In the delay module 506, the fifth resistor R5 works in conjunction with the Schmitt trigger S to extend the time for the current to travel from the second interface K2 to the switch module 507, so that the switch module 507 is turned on later than the current limiting module 505, thus preventing the initial instantaneous high voltage current from damaging the switch module 507.
[0047] The Schmitt trigger (S) operates based on a positive feedback mechanism, where the output signal is fed back to the input, forming a coupling loop. When the input signal exceeds a certain higher threshold, the output signal flips; when the input signal drops to another lower threshold, the output signal flips again. This hysteresis characteristic ensures that the output signal remains stable within the range where the input signal does not change significantly, achieving delayed current output.
[0048] In some examples, the switching module 507 includes: a switching transistor MOS3, the source of which is connected to a third pin 503, the drain of which is connected to a second pin 502, and the gate of which is connected to the output of a Schmitt trigger S.
[0049] In the switching module 507, the resistance of the switching transistor MOS3 is negligible compared to that of the current limiting module 505. Therefore, it can be regarded as a short circuit between the second pin 502 and the third pin 503. The current directly enters the pin 3 from the pin 2, realizing the connection of the entire power battery pack BMS low-voltage short-circuit power-on system.
[0050] In some examples, the current limiting module 505 also includes a third resistor R3. One end of the third resistor R3 is connected to the gate of the switching transistor MOS2, and the other end of the third resistor R3 is grounded. When the first interface K1 is disconnected from the second interface K2, the capacitance of the gate of the switching transistor MOS2 will release a certain current. At this time, because the third resistor R3 is grounded, it can play a discharge role and speed up the turn-off of the switching transistor MOS2.
[0051] In some examples, since there is a capacitor in the gate of the switching transistor MOS3, after the first interface K1 is disconnected from the second interface K2, the capacitor will release a certain current. In order to prevent the current from flowing into the current limiting module 505 through the circuit, a second diode D2 is provided in the delay module 506. The second diode D2 is located between the fifth resistor R5 and the circuit of the second interface K2. Specifically, the positive terminal of the second diode D2 is connected to the second interface K2, and the negative terminal of the second diode D2 is connected to the fifth resistor R5.
[0052] In some examples, similar to the third resistor R3, in order to accelerate the discharge speed of the gate capacitance of the switching transistor MOS3, the switching module 507 also includes a fourth resistor R4, one end of which is connected to the gate of the switching transistor MOS3, and the other end of which is grounded.
[0053] like Figure 2The operation of the power control board 5 shown is as follows: High-voltage power is input through the first pin 501, and passes through the step-down module 504 composed of the first resistor R1, the switching transistor MOS1, and the first diode D1. Low-voltage current is output from the source (S) terminal of the switching transistor MOS1 to the first interface K1. Subsequently, the first interface K1 and the second interface K2 are shorted, and the low-voltage current flows to the current limiting module 505 and the delay module 506 respectively. The switching transistor MOS2 of the current limiting module 505 is turned on, and the current of the DC / DC converter 3 flows into the power control board 5 from the second pin 502 and is grounded through the current limiting module 505. The current flowing to the delay module 506 is delayed by the Schmitt trigger S and then flows into the switching transistor MOS3 of the switching module 507. The switching transistor MOS3 is turned on, and the current in the second pin 502 flows from the switching transistor MOS3 to the third pin 503, and finally enters the negative terminal of the battery module 1.
[0054] When power is not required, the first interface K1 is disconnected from the second interface K2. At this time, no current flows into the gates of switching transistors MOS2 and MOS3, and both MOS2 and MOS3 are turned off. The gate capacitance of MOS2 discharges and is grounded through R3, and the gate capacitance of MOS3 discharges and is grounded through the fourth resistor R4. Ultimately, the entire power-on system is in an open-circuit state, and no current flows, avoiding the problem of power waste caused by some modules remaining powered on in standby mode in traditional power-on methods.
[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.
Claims
1. A low-voltage short-circuit power-on system for a power battery pack BMS, characterized in that, include: Battery module (1), which is used to provide power to the high voltage box (2), BMS module (4) and power control board (5); High-voltage box (2), which is used to distribute the incoming electrical energy; DC / DC converter (3), the DC / DC converter (3) is used to step down the power transmitted to the BMS module (4); BMS module (4), the BMS module (4) is used to control the current switching of each device inside the high voltage box (2) and monitor the working status of the battery module (1); Power control board (5), the power control board (5) is used to control the current on and off of BMS module (4); The positive terminal of the battery module (1) is electrically connected to the first pin (501) of the high voltage box (2) and the power control board (5), respectively. The negative terminal of the battery module (1) is electrically connected to the third pin (503) of the high voltage box (2) and the power control board (5), respectively. The input terminal of the DC / DC converter (3) is electrically connected to the positive terminal of the battery module (1). The output terminal of the DC / DC converter (3) is connected to the second pin (502) of the power control board (5) and the input terminal of the BMS module (4), respectively. The output terminal of the BMS module (4) is electrically connected to the high voltage box (2), and the BMS module (4) is electrically connected to the battery module (1).
2. The power battery pack BMS low-voltage short-circuit power-on system according to claim 1, characterized in that, The power control board (5) further includes: a step-down module (504), a first interface K1, a second interface K2, a current limiting module (505), a delay module (506), and a switching module (507), wherein: The first pin (501) is connected to K1 through a step-down module (504). The step-down module (504) is used to reduce the voltage input to the first pin (501) and transmit the reduced voltage to the first interface K1. The second pin (502) is connected to the second interface K2 through the current limiting module (505). The output of the current limiting module (505) is grounded. The current limiting module (505) is used to reduce the current of the second pin (502) and ground it. The second pin (502) and the third pin (503) are connected by a switch module (507), which is used to control the on / off state between the second pin (502) and the third pin (503). The switch module (507) is connected to the second interface K2 through a delay module (506), which is used to make the switch module (507) turn on later than the current limiting module (505).
3. The power battery pack BMS low-voltage short-circuit power-on system according to claim 2, characterized in that, The step-down module (504) includes a switching transistor MOS1, a first resistor R1 and a first diode D1. The drain of the switching transistor MOS1 is connected to the first pin (501), the gate of the switching transistor MOS1 is connected to the first diode D1 in series and then grounded, and the source of the switching transistor MOS1 is connected to the first interface K1.
4. The power battery pack BMS low-voltage short-circuit power-on system according to claim 3, characterized in that, The current limiting module (505) includes: a switching transistor MOS2 and a second resistor R2, wherein the source of the switching transistor MOS2 is grounded, the drain of the switching transistor MOS2 is connected to the second pin (502) through the second resistor R2, and the gate of the switching transistor MOS2 is connected to the second interface K2.
5. The power battery pack BMS low-voltage short-circuit power-on system according to claim 4, characterized in that, The delay module (506) includes a fifth resistor R5 and a Schmitt trigger S, wherein the second interface K2 is connected in series with the fifth resistor R5 and then connected to the input terminal of the Schmitt trigger S, and the output terminal of the Schmitt trigger S is electrically connected to the switch module (507).
6. The power battery pack BMS low-voltage short-circuit power-on system according to claim 5, characterized in that, The switching module (507) includes: a switching transistor MOS3, the source of which is connected to the third pin (503), the drain of which is connected to the second pin (502), and the gate of which is connected to the output of a Schmitt trigger S.
7. The power battery pack BMS low-voltage short-circuit power-on system according to claim 4, characterized in that, The current limiting module (505) also includes a third resistor R3, one end of which is connected to the gate of the switching transistor MOS2, and the other end of which is grounded.
8. The power battery pack BMS low-voltage short-circuit power-on system according to claim 5, characterized in that, The delay module (506) further includes a second diode D2, which is located between the fifth resistor R5 and the second interface K2. The positive terminal of the diode D2 is connected to the second interface K2, and the negative terminal of the second diode D2 is connected to the fifth resistor R5.
9. The power battery pack BMS low-voltage short-circuit power-on system according to claim 6, characterized in that, The switching module (507) also includes a fourth resistor R4, one end of which is connected to the gate of the switching transistor MOS3, and the other end of which is grounded.