High rate battery pack short circuit identification protection system

Abstract

This utility model discloses a short-circuit identification and protection system for high-rate battery packs, comprising: a control unit, a current change rate detection unit, and a loop switch control unit. The loop switch control unit is connected to a loop switch, one end of which is connected to a sampling unit, and the sampling unit is connected to the current change rate detection unit. The sampling unit is connected to the negative terminal of the battery pack. The positive terminal of the battery pack is connected to one end of a load, and the other end of the load is connected to the loop switch. The current change rate detection unit is connected to the control unit, and the control unit is connected to the loop switch control unit. By implementing this system, the change rate of the battery loop current can be accurately identified to determine whether it is a short circuit or a normal load current change, effectively avoiding the problems of insufficient protection or misjudgment in existing technologies.

Description

Technical Field

[0001] This utility model relates to the field of battery pack technology, and in particular to a short-circuit identification and protection system for high-rate battery packs. Background Technology

[0002] Currently, the two most commonly used battery cells in new energy battery packs are lead-acid batteries and lithium batteries. Lithium battery packs typically integrate a battery management system (BMS) protection board to ensure the safe and efficient use of the battery during operation. Application scenarios for these battery packs include two-wheeled / three-wheeled electric vehicles, four-wheeled electric vehicles, energy storage power stations, and communication base stations.

[0003] To ensure higher efficiency and functional safety during battery pack operation, short-circuit protection is crucial. For example, in high-rate battery packs, peak currents can be very high. Therefore, the short-circuit protection current must be set higher than these peak currents. Otherwise, if a short circuit occurs, the BMS system will detect the short circuit and disconnect the circuit switch due to the excessively high protection current. However, when the MOSFET is switched off, the current has already reached a dangerous level. The surge in current could damage the MOSFET because it cannot withstand the energy surge from the circuit inductance.

[0004] Existing technologies employ phase-shifting current by introducing high-power resistive-capacitive components, which effectively provides protection, but this significantly increases costs. Other existing technologies focus on dual protection mechanisms, but their explanations of high-current protection effectiveness are not in-depth, potentially leading to limitations in practical applications. For example, some technologies can only handle specific current variations, and under high peak current conditions, the protection circuit may not be able to accurately identify and effectively disconnect the circuit within a short time. Therefore, these technical solutions demonstrate inadequacy under some extreme operating conditions.

[0005] Therefore, it is necessary to design a new system to accurately identify the rate of change of battery circuit current in order to determine whether it is a short circuit or a change in normal load current, which can effectively avoid the problems of insufficient protection or misjudgment in the existing technology. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a short-circuit identification and protection system for high-rate battery packs.

[0007] To solve the above-mentioned technical problems, the purpose of this utility model is achieved through the following technical solution: providing a high-rate battery pack short-circuit identification and protection system, comprising: a control unit, a current change rate detection unit, and a loop switch control unit; the loop switch control unit is connected to a loop switch, one end of the loop switch is connected to a sampling unit, and the sampling unit is connected to the current change rate detection unit; the sampling unit is connected to the negative terminal of the battery pack; the positive terminal of the battery pack is connected to one end of a load, and the other end of the load is connected to the loop switch; wherein, the current change rate detection unit is connected to the control unit; and the control unit is connected to the loop switch control unit.

[0008] The further technical solution is as follows: the control unit includes a control chip U1.

[0009] The further technical solution is as follows: the current change rate detection unit includes a start-up current acquisition module, a threshold current acquisition module, and a detection time interval determination module; the start-up current acquisition module and the threshold current acquisition module are respectively connected to the detection time interval determination module; the start-up current acquisition module and the threshold current acquisition module are respectively connected to the control unit; the start-up current acquisition module and the threshold current acquisition module are respectively connected to the acquisition unit.

[0010] The further technical solution is as follows: the starting current acquisition module includes a first comparator, which is connected to the detection time interval determination module and the control unit respectively.

[0011] The further technical solution is as follows: the threshold current acquisition module includes a second comparator, which is connected to the detection time interval determination module and the control unit respectively.

[0012] The further technical solution is as follows: the detection time interval determination module includes an RC circuit.

[0013] The further technical solution is as follows: the RC circuit includes resistor R6, resistor R1 and capacitor CMS2.

[0014] The further technical solution is as follows: the circuit switch includes a discharge switch and a charging switch.

[0015] The further technical solution is as follows: the model of the first comparator and the model of the second comparator are RS331XF respectively.

[0016] The further technical solution is as follows: the starting current acquisition module, the threshold current acquisition module, and the detection time interval determination module are also connected to a setting unit. The setting unit includes a microcontroller, which is used to set the starting current, the detection time interval, and the short-circuit load detection judgment threshold value.

[0017] The advantages of this invention compared to existing technologies are as follows: This invention determines whether the battery is in a short circuit or under normal load by accurately detecting the rate of change of current in the battery circuit. The system includes a control unit, a current change rate detection unit, and a circuit switch control unit. The sampling unit monitors the current change in real time and transmits the data to the current change rate detection unit, which calculates the current change rate. The control unit determines the load state based on this change rate. If the current change rate exceeds a preset threshold, it is determined to be a short circuit, and the circuit switch is promptly controlled to disconnect the circuit, thereby effectively avoiding the problems of misjudgment or insufficient protection in existing technologies and ensuring battery safety.

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments 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 based on these drawings without creative effort.

[0020] Figure 1 Schematic diagram of the high-rate battery pack short-circuit identification and protection system provided in this embodiment of the utility model. Figure 1 ;

[0021] Figure 2 Schematic diagram of the high-rate battery pack short-circuit identification and protection system provided in this embodiment of the utility model. Figure 2 ;

[0022] Figure 3 A detailed circuit diagram of the high-rate battery pack short-circuit identification and protection system provided in this embodiment of the utility model;

[0023] Figure 4 A graph illustrating the short-circuit identification and protection system for a high-rate battery pack provided in this embodiment of the invention.

[0024] Explanation of the markings in the image:

[0025] 10. Control unit; 20. Current change rate detection unit; 30. Loop switch control unit; 40. Battery pack; 50. Load. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0027] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0028] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0029] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0030] New energy battery packs 40 commonly use lead-acid and lithium batteries. Lithium battery packs 40 are generally equipped with a battery management system (BMS) protection board to ensure safe and efficient operation. Short-circuit protection is particularly important in high-rate battery packs 40, especially under conditions of large peak current. Existing technologies use high-power resistors and capacitors for protection, but this is costly, and some dual protection mechanisms are not effective under high current conditions, failing to quickly and effectively address the risk of short circuits under extreme operating conditions, thus exhibiting certain limitations.

[0031] To address this, this utility model provides a high-rate battery pack short-circuit identification and protection system that accurately identifies the rate of change of the battery circuit current to determine whether it is a short circuit or a normal load current change, effectively avoiding the problems of insufficient protection or misjudgment in the prior art.

[0032] Specifically, this high-rate battery pack short-circuit identification and protection system, by combining the control unit 10, the current change rate detection unit 20, and the loop switch control unit 30, accurately identifies the rate of change of current in the battery circuit, thereby determining whether a short circuit has occurred. The system utilizes a startup current acquisition module and a threshold current acquisition module, along with a detection time interval determination module, to effectively distinguish between short-circuit and normal load current fluctuations through dynamic monitoring and judgment of current changes. Simultaneously, the RC circuit design ensures accurate detection of the time interval, avoiding the risks of incomplete protection or misjudgment in traditional technologies. The system also allows for flexible configuration through setting units (such as microcontrollers) to ensure accurate identification of short-circuit loads, improving system reliability and response speed.

[0033] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0034] Please see Figures 1 to 2 A high-rate battery pack short-circuit identification and protection system, characterized in that it includes: a control unit 10, a current change rate detection unit 20, and a loop switch control unit 30. The loop switch control unit 30 is connected to a loop switch, one end of the loop switch is connected to a sampling unit, and the sampling unit is connected to the current change rate detection unit 20. The sampling unit is connected to the negative terminal of the battery pack 40. The positive terminal of the battery pack 40 is connected to one end of a load 50, and the other end of the load 50 is connected to the loop switch. The current change rate detection unit 20 is connected to the control unit 10, and the control unit 10 is connected to the loop switch control unit 30.

[0035] In this embodiment, the control unit 10 is the core component of the entire battery pack 40 short-circuit identification and protection system, responsible for signal acquisition, logic judgment, and control. Upon system startup, the control unit 10 acquires current change information from the current change rate detection unit 20 and compares it with a preset threshold to determine whether the battery system is in a short-circuit state. If a short circuit is detected, the control unit 10 issues a protection signal, instructing the circuit switch control unit 30 to disconnect the battery circuit, ensuring system safety.

[0036] The current change rate detection unit 20 is used to detect the rate of change of the current in the battery pack 40. By measuring the change in the current of the battery pack 40 per unit time (i.e., the current change rate K), it can accurately determine whether the battery circuit is in a normal load state or a short circuit state. When the current change rate K is greater than the preset short circuit threshold (Kth), the system will determine that it is a short circuit and then trigger the protection action. This unit can detect current changes in a short time and can make an accurate judgment even if the current value is small.

[0037] The function of the circuit switch control unit 30 is to control the switching of the battery circuit. The circuit switch control unit 30 is closely connected to the control unit 10 and controls the opening or closing of the circuit switch based on the short-circuit protection signal issued by the control unit 10. If a short circuit is detected, the control unit 10 issues a disconnect signal, and the circuit switch will cut off the battery circuit, thereby protecting the battery pack 40 and other circuits from damage.

[0038] The circuit breaker is a crucial component of the system, responsible for disconnecting the electrical connection between the battery and load 50 upon detecting a short circuit, preventing the short-circuit current from continuing to flow. The state of the circuit breaker (open or closed) is controlled by the circuit breaker control unit 30 to ensure system safety.

[0039] The sampling unit is located between the negative terminal of the battery pack 40 and the current change rate detection unit 20. It is responsible for acquiring current data from the negative terminal of the battery pack 40 and transmitting this data to the current change rate detection unit 20. The function of the sampling unit is to ensure the accuracy of the detected current and to monitor the current status of the battery pack 40 in real time.

[0040] The positive terminal of the battery pack 40 is connected to one port of the load 50, and the other port of the load 50 is connected to the negative terminal of the battery pack 40 via a circuit switch. The direction of current flow is closely related to the state of the load 50. Under normal operating conditions, the battery pack 40 provides current to the load 50, but in the event of a short circuit, the circuit switch disconnects to prevent current from continuing to flow.

[0041] During operation, the rate of change of current in the battery pack 40 is first monitored by the rate of change of current detection unit 20. By detecting the rate of change of current K, the system can quickly determine whether a short circuit has occurred. When the rate of change of current exceeds the set threshold (Kth), the system determines that a short circuit has occurred and activates the protection mechanism.

[0042] After receiving the signal from the current change rate detection unit 20, the control unit 10 determines whether the short circuit condition is met. If a short circuit is detected, the control unit 10 sends a signal through the loop switch control unit 30 to close the loop switch and disconnect the connection between the battery and the load 50.

[0043] In this way, the system can respond to current changes in a short time, avoiding excessive current flow through the battery pack 40 and other sensitive circuits, thus reducing the risk of damage.

[0044] The system uses simple basic components such as comparators, capacitors, resistors, transistors, diodes and microcontrollers, which greatly reduces the design cost. At the same time, due to the use of low-power devices, the system consumes less power during operation.

[0045] By utilizing the current change rate detection mechanism, the system can quickly and accurately determine the state of the battery circuit, reducing the likelihood of misjudgment and ensuring the safety and stability of the system.

[0046] The system can adjust parameters via external devices or a microcontroller based on the characteristics of different battery packs 40 and loads 50. For example, parameters such as the starting current Istar, detection time Δt, and short-circuit judgment threshold Kth can be adjusted according to actual applications to adapt to different scenarios.

[0047] The system can respond promptly when a short circuit occurs in the battery pack 40, quickly cutting off the circuit and protecting the battery pack 40 and other electrical components from damage.

[0048] This high-rate battery pack short-circuit identification and protection system combines current change rate detection with loop switch control to achieve low-cost, high-efficiency short-circuit protection. Its design logic is simple, yet it boasts high reliability and flexibility, making it suitable for various battery pack protection applications and effectively ensuring the safety of the battery pack under high-rate operating conditions.

[0049] In one embodiment, please refer to Figure 3 The aforementioned control unit 10 includes a control chip U1, which is model 74LVC2G74DP. In this embodiment, the loop switch control unit 30 belongs to the terminal of the control chip U1.

[0050] This control chip is responsible not only for the basic control functions of the battery pack 40, but also for the circuit switch control function. Specifically, the pins of this chip are connected to the circuit switch unit, and short-circuit protection is achieved by controlling the current flow.

[0051] In one embodiment, the current change rate detection unit 20 includes a start current acquisition module, a threshold current acquisition module, and a detection time interval determination module. The start current acquisition module and the threshold current acquisition module are respectively connected to the detection time interval determination module. The start current acquisition module and the threshold current acquisition module are respectively connected to the control unit 10. The start current acquisition module and the threshold current acquisition module are respectively connected to the acquisition unit.

[0052] In one embodiment, please refer to Figure 3 The aforementioned startup current acquisition module includes a first comparator, which is connected to both the detection time interval determination module and the control unit 10.

[0053] In one embodiment, please refer to Figure 3 The threshold current acquisition module mentioned above includes a second comparator, which is connected to the detection time interval determination module and the control unit 10.

[0054] In one embodiment, please refer to Figure 3 The aforementioned detection time interval determination module includes an RC circuit.

[0055] In one embodiment, please refer to Figure 3 The aforementioned RC circuit includes resistor R6, resistor R1, and capacitor CMS2.

[0056] In this embodiment, the startup current acquisition module is mainly used to acquire the startup current, ensuring that the system can respond quickly when a current change begins. The first comparator used in the module is connected to the detection time interval module and the control unit 10 to ensure real-time detection of current changes and response.

[0057] The threshold current acquisition module is similar to the startup current acquisition module. It sets a threshold value for current changes; once the rate of change of current exceeds the preset threshold, the system determines it to be in a short-circuit state. This module is connected to the detection time interval module and the control unit 10 via a second comparator.

[0058] The detection time interval determination module uses an RC circuit (resistors R6 and R1, and capacitor CMS2) to determine the detection time interval. The parameter settings of the RC circuit directly affect the detection accuracy of the current change rate. The working principle of the RC circuit is based on the charging and discharging characteristics of capacitors and resistors to ensure reasonable acquisition of the current change rate.

[0059] In one embodiment, please refer to Figure 2 The aforementioned circuit switches include a discharge switch and a charging switch. The design incorporates both a discharge switch and a charging switch, implemented via a control chip. Upon detecting a short circuit, the control chip quickly disconnects the circuit switches, stopping current flow and preventing battery overheating or damage.

[0060] In one embodiment, please refer to Figure 3 The models of the first comparator and the second comparator mentioned above are RS331XF, respectively.

[0061] In one embodiment, the aforementioned starting current acquisition module, threshold current acquisition module, and detection time interval determination module are further connected to a setting unit. The setting unit includes a microcontroller for setting the starting current, detection time interval, and short-circuit load 50 detection threshold value.

[0062] The setting unit includes a microcontroller for configuring the starting current, detection time interval, and short-circuit load 50 detection threshold. The microcontroller can adjust these parameters through external settings or software programming according to the actual needs of different battery packs 40 and loads 50.

[0063] In this embodiment, when the BMS system is powered normally, the microcontroller will enable the current change rate detection circuit.

[0064] When the battery system's loop current I exceeds the preset starting current Istar, the current change rate detection circuit is activated. This circuit calculates the current change rate (K value) over a specified time interval (Δt).

[0065] If the K value is less than the preset short-circuit load 50 detection threshold (Kth), the battery pack 40 system judges it as a normal load 50 state.

[0066] If the value of K is greater than Kth, the system determines that it is in a short circuit state and triggers the protection action by outputting the "Load_chk_out" signal.

[0067] After receiving a short-circuit signal, the microcontroller controls the drive signal "MOS-DRV" of the MOSFET switch to cut off the circuit and protect the battery pack 40 from short-circuit damage. At this time, the system will check the status of the MOSFET to confirm whether the short circuit has been successfully disconnected.

[0068] The comparator is used for real-time detection of the rate of change of current. Specific models such as RS331XF are responsible for the start current acquisition and threshold current acquisition, respectively.

[0069] RC circuits use a combination of resistors and capacitors to set the time interval, ensuring accurate detection of the rate of change of current.

[0070] Single chip: Used for parameter setting and logic judgment to ensure that the system can flexibly adapt to different battery pack 40 and load 50 conditions.

[0071] This embodiment uses basic electronic components and features a simple design, reducing overall cost. Through microcontroller and external circuit settings, key parameters can be adjusted according to the actual application scenario. The system can quickly and accurately identify short-circuit conditions and promptly disconnect the circuit switch, avoiding misjudgment and battery damage.

[0072] In summary, this embodiment provides a short-circuit protection scheme for battery pack 40 based on current change rate detection. It is simple in design, low in cost, and provides rapid and effective protection, thus having high practical value and broad application prospects.

[0073] In addition, please see Figure 3 and Figure 4 The Istar startup current acquisition section includes:

[0074] Resistors RMS1, RMS2, and RMS5 are used for voltage division, converting the input voltage into a signal suitable for the comparator to process.

[0075] Capacitors C2 and CMS1 are used for filtering, removing noise, and ensuring signal stability.

[0076] The first comparator, UMS1, is used to compare the input signal with the reference voltage and output a high or low level.

[0077] The output INT_Istar represents the sampling result of the starting current.

[0078] The threshold current Ith acquisition section includes:

[0079] Resistors RMS7, RMS8, and RMS11 are used for voltage division, converting the input voltage into a signal suitable for comparator processing.

[0080] Capacitors C5 and CMS3 are used for filtering, removing noise, and ensuring signal stability.

[0081] The second comparator, UMS2, is used to compare the input signal with the reference voltage and output a high or low level.

[0082] The INT_Ith output terminal represents the acquisition result of the threshold current.

[0083] The detection time interval determination module includes:

[0084] Resistors RMS3, RMS4, RMS6, RMS9, RMS10, RMS12, and RMS13 are used to set the time constant of the RC circuit.

[0085] The capacitor CMS2 and the resistor together form an RC circuit, which determines the time constant.

[0086] Transistors QMS1 and QMS2 are used for the transmission and amplification of control signals.

[0087] △t is determined by setting the judgment time through the RC circuit.

[0088] The control chip U1 is actually a D flip-flop, used to store and transmit data, and toggles its state according to the input clock signal and data signal.

[0089] The pins VCC, CP, Q, RD, D, SD, and GND represent the pins of the D flip-flop, which are connected to the power supply, clock, output, reset, data, set, and ground, respectively.

[0090] The output Load_chk_out represents the final result of the current change rate determination.

[0091] The entire circuit achieves accurate detection and determination of the rate of change of current by acquiring the starting current and threshold current, combined with the timing setting of the RC circuit and the logic judgment of the D flip-flop.

[0092] Figure 4This figure shows the relationship between the rate of change of current and time, which is used to determine whether the circuit is in a short - circuit state.

[0093] The horizontal axis (t) represents time;

[0094] The vertical axis (I) represents current;

[0095] Key points and lines:

[0096] Istar: Represents the starting current, which is the initial value of the current;

[0097] I1, I2, I3: Represent the current values at different time points;

[0098] t0, t1: Represent different time points;

[0099] The red solid line represents the case where the rate of change of current K2 > Kth, that is, the current rises rapidly with a large slope.

[0100] The blue solid line represents the case where the rate of change of current K1 < Kth, that is, the current rises slowly with a small slope.

[0101] The pink dashed line represents the rate of change of current Kth, which is the threshold value for identifying short - circuit and non - short - circuit loads 50.

[0102] If the rate of change of current K2 > Kth (red solid line), it is judged as a short - circuit condition. This means that the current rises rapidly within a short time, exceeding the set threshold value.

[0103] If the rate of change of current K1 < Kth (blue solid line), it is judged as a non - short - circuit condition. This means that the current rises slowly and does not exceed the set threshold value.

[0104] At time t0, the current starts to rise from Istar.

[0105] At time t1, the current of the red solid line reaches I3, and the current of the blue solid line reaches I2.

[0106] By comparing the slopes of the red solid line and the blue solid line, it can be judged that the slope of the red solid line is greater than Kth, and the slope of the blue solid line is less than Kth.

[0107] In summary, this figure can effectively determine whether the circuit is in a short - circuit state by the relationship between the rate of change of current and time, combined with the set threshold value Kth.

[0108] In this embodiment, when the BMS system is powered on, the single - chip microcomputer enables the rate - of - change - of - current detection unit 20 by setting the high signal "Current_chk_CTL". This unit mainly consists of two parts: the acquisition of the starting current Istar and the acquisition of the threshold current Ith.

[0109] Istar startup current acquisition: The input voltage is converted into a signal suitable for processing by the first comparator UMS1 through a voltage divider and filter circuit composed of resistors RMS2 and RMS5 and capacitors C2 and CMS1.

[0110] The first comparator, UMS1, compares the input signal with the reference voltage and outputs the result to the INT_Istar port. When the loop current I is greater than the detection start current Istar, the current change rate detection unit 20 starts working.

[0111] Threshold current Ith acquisition: Similar to the startup current acquisition section, the input voltage is converted into a signal suitable for processing by the second comparator UMS2 through a voltage divider and filter circuit composed of resistors RMS8 and RMS11 and capacitors C5 and CMS3.

[0112] The second comparator, UMS2, is used to compare the input signal with the reference voltage and outputs the result to the INT_Ith port.

[0113] Within the specified time interval Δt = t1 - t0, the effective value K of the current change rate is detected using the time constant set by the RC circuit. If the value of K is less than the short-circuit load detection threshold value Kth, the battery system is determined to be in a non-short-circuit state; if the value of K is greater than Kth, it is determined to be in a short-circuit state, and a high level is output to "Load_chk_out".

[0114] When the control chip U1 receives a high "Load_chk_out" signal, it immediately controls the MOS transistor drive signal "MOS-DRV" to go low, thereby disconnecting the MOS switch in the circuit, which is also the loop switch. At the same time, the MCU will check whether the MOS switch status "MOS-CHK" is low to confirm whether the MOS switch is properly disconnected, thus achieving short-circuit protection.

[0115] The starting current Istar, the specified detection time Δt = t1 - t0, and the threshold value Kth for short-circuit load detection can all be flexibly set via external resistors and capacitors or microcontroller pins.

[0116] By utilizing the characteristics of comparator circuits, combined with simple signal delay circuits and microcontroller logic control, a low-cost, low-power, and flexible short-circuit identification and protection scheme can be implemented.

[0117] In this embodiment, the detection starting current Istar is generally set to 1.5C. For example, if the battery pack 40 has a capacity of 200AH, then Istar is 300A.

[0118] The specified detection time Δt = t1 - t0 generally does not exceed 5 μs.

[0119] The threshold value Kth for short-circuit load detection is generally set between 80 and 100 A / μs.

[0120] These parameters need to be adjusted according to the specific battery pack 40 and the actual signal detection and response time of the BMS protection board to ensure accurate and reliable short circuit identification and protection functions.

[0121] In summary, the core of the system design in this embodiment lies in its ability to detect the rate of change of current in the power circuit in a timely and rapid manner through a simple and effective circuit structure, accurately determine the load state, and take protective measures quickly when a short circuit occurs. It has the advantages of low cost, low power consumption, and flexible use.

[0122] The aforementioned high-rate battery pack short-circuit identification and protection system determines whether the battery is in a short-circuit state or a normal load state by accurately detecting the rate of change of current in the battery circuit. The system includes a control unit 10, a current change rate detection unit 20, and a circuit switch control unit 30. The sampling unit monitors the current change in real time and transmits the data to the current change rate detection unit 20, which calculates the current change rate. The control unit 10 determines the load state based on the change rate. If the current change rate exceeds a preset threshold, it is determined to be a short circuit, and the circuit switch is promptly controlled to disconnect the circuit, thereby effectively avoiding the misjudgment or insufficient protection problems existing in the prior art and ensuring battery safety.

[0123] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A high-rate battery pack short-circuit identification and protection system, characterized in that, include: The system includes a control unit, a current change rate detection unit, and a loop switch control unit. The loop switch control unit is connected to a loop switch, one end of which is connected to a sampling unit. The sampling unit is connected to the current change rate detection unit. The sampling unit is connected to the negative terminal of the battery pack. The positive terminal of the battery pack is connected to one end of a load, and the other end of the load is connected to the loop switch. The current change rate detection unit is connected to the control unit, and the control unit is connected to the loop switch control unit.

2. The high-rate battery pack short-circuit identification and protection system according to claim 1, characterized in that, The control unit includes a control chip U1.

3. The high-rate battery pack short-circuit identification and protection system according to claim 1, characterized in that, The current change rate detection unit includes a start-up current acquisition module, a threshold current acquisition module, and a detection time interval determination module. The start-up current acquisition module and the threshold current acquisition module are respectively connected to the detection time interval determination module. The start-up current acquisition module and the threshold current acquisition module are respectively connected to the control unit. The start-up current acquisition module and the threshold current acquisition module are respectively connected to the sampling unit.

4. The high-rate battery pack short-circuit identification and protection system according to claim 3, characterized in that, The startup current acquisition module includes a first comparator, which is connected to both the detection time interval determination module and the control unit.

5. The high-rate battery pack short-circuit identification and protection system according to claim 4, characterized in that, The threshold current acquisition module includes a second comparator, which is connected to the detection time interval determination module and the control unit.

6. The high-rate battery pack short-circuit identification and protection system according to claim 3, characterized in that, The detection time interval determination module includes an RC circuit.

7. The high-rate battery pack short-circuit identification and protection system according to claim 6, characterized in that, The RC circuit includes resistor R6, resistor R1, and capacitor CMS2.

8. The high-rate battery pack short-circuit identification and protection system according to claim 1, characterized in that, The circuit switch includes a discharge switch and a charging switch.

9. The high-rate battery pack short-circuit identification and protection system according to claim 5, characterized in that, The first comparator and the second comparator are model RS331XF, respectively.

10. The high-rate battery pack short-circuit identification and protection system according to claim 3, characterized in that, The starting current acquisition module, the threshold current acquisition module, and the detection time interval determination module are also connected to a setting unit. The setting unit includes a microcontroller and is used to set the starting current, the detection time interval, and the short-circuit load detection threshold value.

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