Power supply detection device, sampling circuit board and battery management system

Abstract

The utility model discloses a power supply detection device, a sampling circuit board and a battery management system, and relates to the technical field of electric leakage detection, the power supply detection device comprises a power supply input end, a sampling chip and a current limiting circuit; the sampling chip is provided with a power supply end, a first acquisition end and a second acquisition end, the input end of the current limiting circuit is connected with the power supply input end, and the output end of the current limiting circuit is connected with the power supply end of the sampling chip; the first acquisition end and the second acquisition end of the sampling chip are respectively connected with the input end and the output end of the current limiting circuit, and the sampling chip is used for acquiring an electric leakage signal flowing through the current limiting circuit through the first acquisition end and the second acquisition end. Therefore, according to the power supply detection device provided by the invention, the current flowing from the power supply to the power supply end of the sampling chip is detected by using the redundant sampling ports on the sampling chip, so that the magnitude of the leakage current flowing into the sampling chip can be detected while the number of components on the sampling circuit board is not increased; and miniaturization design of a circuit, a corresponding circuit board and equipment is facilitated.

Description

Technical Field

[0001] This application relates to the field of leakage current detection technology, and in particular to power detection devices, sampling circuit boards and battery management systems. Background Technology

[0002] The CSC board (cell supervision circuit) is a circuit board used to detect parameters such as battery voltage, temperature, and current. The CSC board primarily uses an AFE chip (Analog Front End) to acquire and process battery parameters such as voltage and current, converting these signals into digital information for analysis by a microcontroller.

[0003] When CSC boards are used in electrical devices, such as electric vehicles, the accuracy of signal acquisition by the CSC board may be affected because the battery may continue to discharge unexpectedly. In this case, the battery management system may misjudge the battery status, causing the electric vehicle's control unit to receive incorrect signals, which in turn affects the stability of the electric vehicle's power output and may even cause safety problems.

[0004] In related technologies, power detection devices are designed to monitor potential problems. However, this would only increase the power detection circuit structure, thus affecting the miniaturization design of the CSC board. Utility Model Content

[0005] In view of the above problems, this application provides a power detection device, a sampling circuit board, and a battery management system, which aims to reduce the size of the power detection device.

[0006] In a first aspect, this application provides a power supply detection device, comprising: a power input terminal, a sampling chip, and a current limiting circuit; the sampling chip has a power supply terminal, a first acquisition terminal, and a second acquisition terminal; the input terminal of the current limiting circuit is connected to the power input terminal, and the output terminal of the current limiting circuit is connected to the power supply terminal of the sampling chip; the first acquisition terminal is connected to the input terminal of the current limiting circuit, and the second acquisition terminal is connected to the output terminal of the current limiting circuit; the sampling chip is used to acquire leakage current signals flowing through the current limiting circuit through the first acquisition terminal and the second acquisition terminal.

[0007] The power detection device can detect leakage current flowing from the power supply to the power terminal of the sampling chip. When leakage current flows through the current limiting circuit at the power input terminal, the current limiting circuit generates a corresponding leakage signal. This signal is then connected to the current limiting circuit via the redundant ports (first and second acquisition terminals) of the sampling chip, enabling the acquisition of the input leakage signal. Therefore, this application achieves leakage current detection by utilizing the redundant ports (first and second acquisition terminals) of the sampling chip without adding any components or circuits. This allows both the power detection device and the circuit board using it to maintain their original size and layout, eliminating the need for redesign or rework, thus facilitating miniaturization.

[0008] In some implementations, the current limiting circuit includes a first resistor, with a first end connected to the power input terminal and a second end connected to the power supply terminal of the sampling chip.

[0009] Understandably, when leakage current flows into the power input terminal, a corresponding voltage drop will be generated across the first resistor. Based on this voltage drop and the specific value of the first resistor, and using Ohm's law, the magnitude of the leakage current can be calculated. This allows for easy comparison with a reference value to determine whether the leakage current exceeds the reference value.

[0010] In some embodiments, the power detection device further includes a filtering circuit, which is connected to the output terminal of the current limiting circuit and the power supply terminal of the sampling chip, for filtering the power signal input to the sampling chip.

[0011] Understandably, this ensures that the power signal received by the sampling chip is filtered, thereby preventing noise and interference from affecting the normal operation of the sampling chip.

[0012] In some implementations, the filter circuit includes a first capacitor, the first terminal of which is connected to the output terminal of the current limiting circuit and the power supply terminal of the sampling chip, and the second terminal of the first capacitor is grounded.

[0013] Understandably, this can form a simple low-pass filter to filter out high-frequency noise in the power supply signal.

[0014] In some implementations, the sampling chip includes a first signal output terminal, through which the sampling chip outputs a leakage current signal.

[0015] Understandably, this first signal output terminal can be used to connect other components, and the leakage signal can be output to other components to calculate the corresponding leakage current.

[0016] Secondly, this application also proposes a power supply detection device, which includes a first detection unit and a second detection unit: the first detection unit includes a first power input terminal, a first sampling chip and a first current limiting circuit, the first sampling chip has a first power supply terminal, the input terminal of the first current limiting circuit is connected to the first power input terminal, and the output terminal of the first current limiting circuit is connected to the power supply terminal of the first sampling chip; the second detection unit is connected to the first current limiting circuit and is used to collect the leakage current signal flowing through the first current limiting circuit.

[0017] Understandably, when the first sampling chip of the first detection unit lacks an additional acquisition port for acquiring the leakage current signal flowing through it, the second detection unit can be used to detect the leakage current signal on the first sampling chip of the first detection unit. Thus, even if some first sampling chips lack additional sampling ports, leakage current detection can still be performed using the second detection unit, ensuring that the leakage current of all first detection units can be accurately monitored. Furthermore, the second detection unit is an existing unit in the circuit; therefore, the power detection device and the circuit board using it can maintain their original size and layout without redesign, which is beneficial for miniaturization.

[0018] In some embodiments, the second detection unit includes a second power input terminal, a second sampling chip, and a second current limiting circuit. The second sampling chip has a second power input terminal and at least one set of first sampling ports, the first sampling ports including a third acquisition terminal and a fourth acquisition terminal. The input terminal of the second current limiting circuit is connected to the second power input terminal, and the output terminal of the second current limiting circuit is connected to the second power input terminal of the second sampling chip. The third acquisition terminal is connected to the input terminal of the first current limiting circuit, and the fourth acquisition terminal is connected to the output terminal of the first current limiting circuit. The second sampling chip is used to acquire the leakage current signal flowing through the first current limiting circuit through the third acquisition terminal and the fourth acquisition terminal.

[0019] It is understandable that the second detection unit may also include a second sampling chip. The difference between the first and second detection units is that the second sampling chip in the second detection unit has a sampling port. Thus, when the first sampling chip does not have an additional sampling port, leakage current detection can be performed using other second sampling chips with available sampling ports. Similarly, leakage current detection can be performed using existing components in the circuit. This allows for the detection of leakage signals acting on each sampling chip without adding additional components, which is beneficial for the miniaturization design of circuits, circuit boards, and related equipment.

[0020] In some embodiments, the second detection unit includes a third sampling chip with a third sampling port, which includes a seventh acquisition terminal and an eighth acquisition terminal. The seventh acquisition terminal of the third sampling port is connected to the input terminal of the first current limiting circuit, and the eighth acquisition terminal of the third sampling port is connected to the output terminal of the first current limiting circuit. The third sampling chip is used to acquire the leakage current signal flowing through the first current limiting circuit through the seventh acquisition terminal and the eighth acquisition terminal.

[0021] Therefore, even if none of the sampling chips in the original circuit have additional sampling ports, leakage current can be acquired by adding a third sampling chip. This ensures that the leakage current signal of each sampling chip can be acquired and monitored under any circumstances.

[0022] In some implementations, there are multiple first detection units, and a second detection unit is used to collect leakage current signals flowing through the first current limiting circuit of at least one first detection unit; or, there are multiple first detection units and multiple second detection units, and each second detection unit collects leakage current signals flowing through the first current limiting circuit of at least one first detection unit.

[0023] It is understandable that the second detection unit can perform leakage signal detection on a one-to-one basis or on a one-to-many basis on the first detection unit.

[0024] In some implementations, the first current limiting circuit includes a second resistor, with a first end of the second resistor connected to a first power input terminal and a second end of the second resistor connected to a first power input terminal of the first sampling chip.

[0025] Thus, by detecting the voltage across the second resistor and the resistance of the second resistor, the leakage current flowing into the first sampling chip of the first detection unit can be calculated.

[0026] In some embodiments, the first detection unit further includes a first filtering circuit, which includes a second capacitor. The first terminal of the second capacitor is connected to the output terminal of the first current limiting circuit and the first power supply terminal of the first sampling chip, and the second terminal of the second capacitor is grounded.

[0027] Understandably, this can form a simple low-pass filter, and after filtering, the detection result will be more accurate when detecting leakage current in the first detection unit.

[0028] In some implementations, the second current limiting circuit includes a third resistor, with a first end connected to the second power input terminal and a second end connected to the second power input terminal of the second sampling chip.

[0029] Thus, by detecting the voltage across the third resistor and the resistance value of the third resistor, the leakage current flowing into the second sampling chip of the second detection unit can be calculated.

[0030] In some embodiments, the second detection unit further includes a second filtering circuit, which includes a third capacitor. The first terminal of the third capacitor is connected to the output terminal of the second current limiting circuit and the second power supply terminal of the second sampling chip, and the second terminal of the third capacitor is grounded.

[0031] Understandably, this can form a simple low-pass filter, and after filtering, the detection result will be more accurate when detecting leakage current in the second detection unit.

[0032] In some embodiments, when there is only one second detection unit, the second detection unit further includes a second signal output terminal, through which the second detection unit outputs a leakage current signal; when there are multiple second detection units, the output terminal of the previous second detection unit is connected to the input terminal of the next second detection unit, and the last second detection unit includes a third signal output terminal, through which multiple second detection units output a leakage current signal.

[0033] Understandably, regardless of the number of second detection units, leakage current signals can be effectively acquired and output, ensuring that the leakage current of all detection units can be accurately detected. This design not only simplifies circuit design and improves the overall reliability of the system, but also helps to achieve miniaturization of the circuit board.

[0034] Thirdly, this application proposes a sampling circuit board, which includes a circuit board and a power detection device as described above, wherein the power detection device is integrated into the circuit board.

[0035] Understandably, even a small leakage current can degrade the performance of the sampling chip, affecting the stability and reliability of the entire sampling circuit board system. Therefore, by integrating a power detection device or power detection unit onto the sampling circuit board, the board can anticipate the presence of leakage current, ensuring that the sampling chip can detect leakage current before it is damaged or loses its original operating performance, allowing for appropriate countermeasures and ultimately significantly improving the durability and safety of the device.

[0036] Fourthly, this application proposes a battery management system, which includes a sampling module and a control module. The sampling module includes the sampling circuit board mentioned above, and the input terminal of the control module is connected to the signal output terminal of the sampling circuit board. The control module is used to receive the signal output by the sampling module.

[0037] This enables efficient management and monitoring of battery cells.

[0038] In some implementations, the sampling module has a signal output terminal, through which the sampling module outputs a leakage current signal; the input terminal of the control module is connected to the signal output terminal of the sampling module, and the output terminal of the control module is connected to the electrical device; the control module is used to receive the leakage current signal output by the sampling module and control the electrical device to perform corresponding operations according to the leakage current signal.

[0039] Understandably, the control module can receive the leakage current signal collected by the sampling module and determine the corresponding current value through the leakage current signal. This allows the specific value of the leakage current to be determined based on the leakage current signal, which facilitates subsequent data comparison and determines whether the specific value of the leakage current exceeds the normal range.

[0040] In some implementations, the control module integrates a comparison circuit. The comparison circuit has a first signal input terminal and a second signal input terminal. The first signal input terminal of the comparison circuit is connected to the signal output terminal of the sampling module, and the second signal input terminal of the comparison circuit is connected to a current reference signal. The comparison circuit is used to compare the leakage current signal with the current reference signal, and outputs a first comparison signal when the current value corresponding to the leakage current signal is greater than the current value corresponding to the current reference signal. The control module is used to determine the power supply leakage based on the first comparison signal and control the electrical device to issue a corresponding alarm signal.

[0041] Thus, once the actual current value equals or exceeds the current comparison value, the comparison circuit will output the corresponding comparison signal, indicating that the leakage current exceeds the safe range, thereby improving the safety and reliability of the system.

[0042] In some implementations, the control module integrates a first comparator and a second comparator. One signal input terminal of the first comparator is connected to the signal output terminal of the sampling circuit board, and the other signal input terminal of the first comparator is connected to a first current reference signal. The first comparator compares the leakage signal with the first current reference signal and outputs a second comparison signal when the current value corresponding to the leakage signal is greater than the current value corresponding to the first current reference signal. One signal input terminal of the second comparator is connected to the signal output terminal of the sampling circuit board, and the other signal input terminal of the second comparator is connected to the second current reference signal. The second comparator compares the leakage signal with the second current reference signal and outputs a third comparison signal when the current value corresponding to the leakage signal is greater than the current value corresponding to the second current reference signal. The first comparator operates when the sampling chip in the sampling circuit board is in standby mode, and the second comparator operates when the sampling chip in the sampling circuit board is in operating mode. The control module determines power leakage based on the second comparison signal and / or the third comparison signal, and controls the electrical device to issue a corresponding alarm signal.

[0043] Understandably, by setting current reference signals for different operating states of the sampling chip in the sampling module, where the first and second current reference signals are respectively used when the sampling chip is in operating mode and an alarm signal is output if the detected leakage current exceeds the current value corresponding to the second current reference signal, the system can monitor the current consumption of the sampling chip more intelligently and accurately. This not only improves the system's energy efficiency and safety but also optimizes fault diagnosis and maintenance processes, thereby improving the overall performance of power equipment and the user experience.

[0044] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the related technologies of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0046] Figure 1 A circuit diagram of the first embodiment of the power detection device provided in this application;

[0047] Figure 2 A circuit diagram of the second embodiment of the power detection device provided in this application;

[0048] Figure 3 A circuit diagram of the third embodiment of the power detection device provided in this application;

[0049] Figure 4 This is a schematic diagram of the architecture of the first embodiment of the battery management system provided in this application;

[0050] Figure 5 A circuit diagram of the second embodiment of the battery management system provided in this application;

[0051] Figure 6 A circuit diagram of the third embodiment of the battery management system provided in this application;

[0052] Figure 7 A circuit diagram of the fourth embodiment of the battery management system provided in this application;

[0053] Figure 8 A circuit diagram of the fifth embodiment of the battery management system provided in this application.

[0054] The reference numerals in the detailed embodiments are as follows:

[0055] Sampling chip 110, current limiting circuit 120, filtering circuit 130;

[0056] First detection unit 200, first sampling chip 210, first current limiting circuit 220, first filtering circuit 230, second detection unit 300, second sampling chip 311, second current limiting circuit 312, second filtering circuit 313, third sampling chip 321;

[0057] Sampling module 400, power detection device 410, control module 500, comparison circuit 511, power consumption device 600.

[0058] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0059] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0060] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0061] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more (including two), unless otherwise explicitly defined.

[0062] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0063] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0064] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of power battery applications, market demand is also constantly increasing.

[0065] The inventors have observed that, in order to better manage batteries and ensure their healthy use, battery monitoring and management are typically implemented, with the battery management system playing a crucial role. The CSC board (cell supervision circuit) in the battery management system is a circuit board that detects parameters such as battery voltage, temperature, and current. The CSC board primarily uses an AFE chip (Analog Front End) to acquire and process battery voltage, current, and temperature data, converting these signals into digital information for analysis by the microcontroller.

[0066] Furthermore, the AFE chip on the CSC board of the power battery system is mainly used to monitor the voltage, current, and temperature of individual cells. The corresponding voltage, current, and temperature signals are collected through the sampling port on the AFE chip, and then the signals are converted by the analog-to-digital converter built into the AFE chip. In this way, it can ensure that the battery operates within a safe range. These data are transmitted to the corresponding main control circuit for analysis and processing through a serial communication interface. This main control unit can be the main control circuit on the BMS board in the battery management system.

[0067] As can be seen, AFE chips or CSC boards enable battery monitoring and management. However, in practical applications, AFE chips and CSC boards may experience various malfunctions. For example, when applied to electric vehicles, users may find that the charging control system cannot accurately determine when to start charging, the charging rate, and when to stop charging. Frequent false alarms or vehicle performance issues may also occur, ultimately leading to user distrust and negatively impacting the user experience. In more serious cases, the battery management system in electric vehicles may malfunction, causing the control system to make incorrect judgments and generate incorrect control signals, potentially leading to safety issues.

[0068] The applicant's research revealed that the primary cause of the aforementioned technical problem lies in the fact that the CSC board is susceptible to leakage current when detecting battery parameters, leading to inaccurate test results. Leakage current refers to current flowing in an unintended path. In a BMS, leakage current can occur between the power supply terminal of the AFE chip and the battery connector, resulting in unexpected energy loss and causing the AFE chip to malfunction, thus impacting the user experience. Therefore, to mitigate this issue, solutions have been developed that control the process by suppressing leakage current generation, eliminating leakage current, or detecting leakage current.

[0069] On the one hand, leakage current is mainly caused by hardware quality issues or component damage, which can lead to leakage current exceeding specifications. When the leakage current reaches a certain level, it enters the AFE chip along with the detection signal, damaging the AFE chip and causing inaccurate detection results. Suppressing leakage current requires the use of higher-specification components and circuit boards, and due to manufacturing processes, inherent hardware problems are difficult to overcome.

[0070] On the other hand, leakage current can be detected by adding a leakage current detection circuit, and then this interference can be eliminated in the control. For example, some exemplary power detection devices include a first amplification circuit and / or a second amplification circuit, which amplifies the change in leakage current and outputs a corresponding amplified voltage when there is a slight change in the leakage current of the AFE chip. By detecting the amplified voltage, the change in leakage current can be obtained, thereby improving the detection accuracy of leakage current. However, the addition of the first amplification circuit and / or the second amplification circuit for detecting leakage current will increase the number of components and cost of the power detection device, which will also affect the miniaturization design of the CSC board.

[0071] Based on the shortcomings or difficulties of the aforementioned solutions, this application proposes a leakage current detection scheme that can alleviate the pain points of the above solutions and achieve leakage current detection. Specifically, this application proposes a power supply detection device to implement leakage current detection. This application aims to utilize the existing AFE chip resources and architecture of the power supply detection device to monitor leakage current without adding additional hardware components to the CSC board. The core of this method lies in utilizing the existing AFE chip on the CSC board, using the remaining unused sampling ports when the AFE chip performs its basic function to detect leakage current. Of course, if there are multiple AFE chips on the CSC board, the unused sampling ports are prioritized during the design. If all are used, a third sampling chip is then considered for implementation. These methods can achieve leakage current detection. The advantage is that it does not require additional circuits or components, nor does it require circuit fabrication or redundant circuit design, reducing hardware costs and the space occupancy of the circuit or CSC board, thereby improving the system integration and reliability.

[0072] The power detection device proposed in this application can be applied to CSC boards and other circuit boards with AFE chips. These circuit boards with AFE chips can be used in medical devices, such as electrocardiographs and blood pressure monitors; in industrial automation, such as temperature controllers and pressure detectors; in communication systems, such as receiving and processing radio frequency signals; in consumer electronics, such as smartphones and tablets; and in home energy storage.

[0073] The power detection device proposed in this application can also be applied to the power supply of various objects, especially in scenarios where batteries are used as the power source. Specifically, it can be used in the CSC board of the battery to monitor the leakage current in the CSC board in real time.

[0074] The battery proposed in this application can be used, but is not limited to, in electrical devices such as vehicles, ships, or aircraft. The power system of such an electrical device can be constructed using the battery disclosed in this application. This helps to suppress or eliminate leakage current in the CSC board of the battery management system, improving user satisfaction with the device and enhancing its reliability. Simultaneously, it ensures that the size of the device does not increase due to the addition of leakage current detection functionality, thus facilitating miniaturization design.

[0075] This application provides an electrical device that uses this battery as a power source, thereby reducing the negative impact of leakage current. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0076] For ease of explanation, the following embodiments use a vehicle as an example of an electrical device according to one embodiment of this application. The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery is installed inside the vehicle, and the battery can be located at the bottom, front, or rear of the vehicle. The battery can be used to power the vehicle; for example, the battery can serve as the vehicle's operating power source. The vehicle may also include a controller and a motor. The controller is used to control the battery to power the motor, for example, to meet the power needs of the vehicle during starting, navigation, and driving.

[0077] In some embodiments of this application, the battery can not only serve as the operating power source for the vehicle, but also as the driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0078] A battery can contain multiple battery cells, which can be connected in series, parallel, or a combination thereof. A combination of series and parallel connections means that some battery cells are connected in series while others are in parallel. Multiple battery cells can be directly connected in series, parallel, or a combination thereof. The battery may also include other structures, such as a busbar for electrical connection between the multiple battery cells. Correspondingly, the CSC board can provide multiple power detection devices for each battery cell. These power detection devices can be connected to the battery via a battery connector for detection.

[0079] According to some embodiments of this application, such as Figure 1 The diagram shown is a circuit diagram of a power supply detection device according to this application. This power supply detection device includes a power input terminal, a sampling chip 110, and a current limiting circuit 120. The sampling chip 110 has a power supply terminal BAT1, a first acquisition terminal, and a second acquisition terminal. The input terminal of the current limiting circuit 120 is connected to the power input terminal, and the output terminal of the current limiting circuit 120 is connected to the power supply terminal of the sampling chip 110. The first acquisition terminal and the second acquisition terminal of the sampling chip 110 are respectively connected to the input terminal and the output terminal of the current limiting circuit 120. The sampling chip 110 is used to acquire leakage current signals flowing through the current limiting circuit 120 through the first acquisition terminal and the second acquisition terminal.

[0080] It should be noted that leakage signals are commonly in the form of leakage current signals.

[0081] The power detection device in this embodiment aims to detect leakage current signals acting on the sampling chip on the sampling circuit board without adding any components, thereby ensuring the stable operation of the power system and improving overall safety. Specifically, this embodiment utilizes the idle sampling port of the sampling chip 110 to achieve efficient leakage current monitoring of the sampling chip 110 without adding any additional hardware, making it suitable for various electrical devices ranging from electric vehicles to personal electrical equipment.

[0082] Alternatively, in one example, the sampling chip 110 is an AFE chip, and the sampling circuit board is a CSC board.

[0083] In this embodiment, the power input terminal is used to connect to a power source, enabling the sampling chip 110 to enter normal operating mode. However, it should be noted that when the power input terminal is not in a conducting state, leakage signals may exist due to aging, damage, or other reasons related to the insulating material. These leakage signals can be leakage current signals, which flow to the sampling chip 110 through the current limiting circuit 120, interfering with the normal operation of the sampling chip 110, such as causing signal crosstalk or other problems.

[0084] In this embodiment, the input terminal of the current limiting circuit 120 is connected to the power input terminal, and the output terminal of the current limiting circuit 120 is connected to the power supply terminal BAT1 of the sampling chip 110. It is understood that when leakage current exists, the leakage current also needs to pass through the current limiting circuit 120 to reach the sampling chip 110. Therefore, the current limiting circuit 120 responds to the leakage current by generating a corresponding leakage signal, which can be detected by the sampling port of the sampling chip 110, thereby achieving leakage current monitoring. Thus, the current limiting circuit 120 not only plays a protective and regulatory role but also serves as an indirect leakage current detection element, making the entire circuit design simpler, eliminating the need for additional detection circuitry, and also facilitating the miniaturization design of the power supply detection device.

[0085] In this embodiment, the first signal acquisition terminal and the second signal acquisition terminal of the sampling chip 110 are respectively connected to the two ends of the current limiting circuit 120, and can acquire the leakage current signal on the current limiting circuit 120. In this way, the leakage current signal acting on the sampling chip 110 itself can be detected through the extra sampling port of the sampling chip 110, without the need to add an additional acquisition circuit, thereby reducing the size of this power detection device and the size of the circuit board on which this power detection device is applied.

[0086] Alternatively, the leakage signal can be a voltage change, a current change, or other form of electronic signal, depending on the circuit design and the input requirements of the sampling chip.

[0087] It should be noted that the output of the sampling chip 110 in this embodiment is not limited to any particular component and can be configured according to the requirements of different BMS system architectures. In practical applications, the leakage signal can be directly determined in the sampling chip 110 to determine the corresponding current value, or the leakage signal can be output to the main control circuit in the BMU board connected to the sampling chip 110, and the main control circuit can then determine the corresponding current value accordingly.

[0088] In one embodiment, multi-level detection logic can be designed to enable the system to distinguish between different levels of leakage current and take different countermeasures. For example, minor leakage current may only need to be recorded and continuously monitored, while severe leakage current requires immediate action, such as cutting off the power supply or issuing an emergency warning.

[0089] In practical applications, this power detection device can be applied to CSC boards. It is assumed that a certain leakage current is input to the power terminal BAT1 of the sampling chip 110 through the current limiting circuit 120. The first signal acquisition terminal and the second signal acquisition terminal of the sampling chip 110 continuously monitor the voltage or current change on the current limiting circuit 120. Once a leakage signal is detected, the sampling chip 110 will determine the level of leakage current according to a preset threshold. If the leakage signal reaches a certain threshold, it will feed the signal back to the user or back-end developers for corresponding measures.

[0090] It should be noted that the key feature of this power detection device is to collect leakage current signals on the current limiting circuit 120 through the extra sampling ports of the sampling chip 110. Therefore, in practical applications, this power detection device can be used in CSC boards or other sampling circuit boards with sampling chips.

[0091] Therefore, the power detection device can capture the leakage current of the sampling chip 110, enabling the circuit board using this device to monitor the status of the sampling chip 110 in real time and promptly detect potential faults. Furthermore, the power detection device in this embodiment can directly acquire the leakage signal from the current limiting circuit 120 through the sampling port of the sampling chip 110, avoiding the need for additional components in the power detection device for leakage current detection. This facilitates the miniaturization design of the sampling circuit board. For example, applying this power detection device to a CSC board can reduce the area occupied by the CSC board while detecting the leakage signal of the sampling chip 110, further contributing to the miniaturization of the CSC board.

[0092] In one embodiment, such as Figure 1 As shown, the current limiting circuit 120 includes a first resistor R1, the first end of the first resistor R1 is connected to the power input terminal, and the second end of the first resistor R1 is connected to the power supply terminal BAT1 of the sampling chip 110.

[0093] It is understood that the current limiting circuit 120 can be the first resistor R1, and in other embodiments, it can be other components, depending on the complexity of the application scenario of the power detection device. Importantly, these components are at least part of the current limiting circuit 120 and are not additional components added specifically for detecting leakage current. Thus, leakage current is detected using the current limiting circuit 120, avoiding the need to add components to the circuit board or the power detection device.

[0094] It should be explained that when leakage current flows through the first resistor R1 to the power supply terminal of the sampling chip 110 from the power input terminal, the first resistor R1 acts on the leakage current signal, forming a corresponding voltage drop across it. The first signal acquisition terminal of the sampling chip 110 detects the voltage at one end of the resistor, and the second signal acquisition terminal detects the voltage at the other end of the resistor. Then, based on the specific value of the first resistor R1, the magnitude of the corresponding leakage current can be calculated. Ohm's law can be used for the specific calculation. In this way, the leakage current output from the power input terminal is effectively monitored, thereby reducing the impact of leakage current on the sampling chip 110 and improving the safety and reliability of the system.

[0095] In some applications, the specific resistance value of the first resistor R1 can be determined based on the actual application. Specifically, a smaller first resistor R1 amplifies voltage changes (because a smaller resistance value results in a smaller voltage drop corresponding to a larger current change), meaning the system can more sensitively detect minute leakage current changes; however, this may also amplify noise in the overall circuit, affecting measurement accuracy. A larger first resistor R1 increases power loss in the circuit (because a larger resistance means a larger voltage drop for the same leakage current, resulting in more power loss); simultaneously, a larger resistance value also reduces sensitivity to minute leakage currents, as the resulting voltage drop is small and may be difficult to detect. Therefore, by appropriately selecting the value of the first resistor R1, both the sensitivity and accuracy of leakage current detection can be improved, while power loss in the circuit can be controlled, ensuring the safe operation of the sampling chip 110.

[0096] In summary, connecting a first resistor R1 with an appropriate resistance value between the power input terminal and the sampling chip 110 converts the leakage current into a detectable voltage drop. The sampling chip 110 calculates the leakage current magnitude by detecting the voltage difference across this resistor, thereby achieving effective monitoring of the leakage current. Furthermore, a smaller resistance value amplifies voltage changes and improves detection sensitivity; a larger resistance value increases power loss. Therefore, appropriately selecting the value of the first resistor R1 can control power loss while ensuring detection accuracy.

[0097] In one embodiment, such as Figure 1As shown, the power detection device also includes a filter circuit 130, which is connected to the output terminal of the current limiting circuit 120 and the power supply terminal of the sampling chip 110, and is used to filter the power signal input to the sampling chip 110.

[0098] In the above embodiment, the power detection device also includes a filter circuit 130. Thus, the filter circuit 130 can further improve the quality of the power signal and reduce false alarms and leakage current caused by power fluctuations or noise.

[0099] In one embodiment, the filter circuit 130 can select a suitable filter type, such as a low-pass filter, a high-pass filter, or a band-pass filter, according to actual application requirements to meet specific frequency response requirements.

[0100] In one embodiment, the filter circuit 130 can be composed of components such as capacitors and inductors, which can effectively filter out high-frequency noise and other interference signals, thereby improving the stability of the power supply.

[0101] In summary, by adding a filter circuit 130 to the power supply detection device, the quality of the power signal received by the sampling chip 110 can be improved. This indirectly enhances the performance of the power supply detection device 410, enabling the acquisition of more accurate leakage current signals.

[0102] In one embodiment, such as Figure 1 As shown, the filter circuit 130 includes a first capacitor C1. The first end of the first capacitor C1 is connected to the output of the current limiting circuit 120 and the power supply terminal of the sampling chip 110, while the second end of the first capacitor C1 is grounded. It can be understood that the filter circuit 130 in this embodiment uses a simple low-pass filter. The first end of the first capacitor C1 is connected to the output of the current limiting circuit 120 and the power supply terminal of the sampling chip 110, while the second end of the first capacitor C1 is grounded. This effectively filters out high-frequency noise and ripple, ensuring that the power signal received by the sampling chip 110 is purer and more stable.

[0103] In some practical applications, the selection of the first capacitor C1 needs to consider the frequency characteristics of the power supply signal and the operating requirements of the sampling chip 110. Generally, a larger capacitance of the first capacitor C1 results in better filtering, but it may also introduce greater phase delay. Therefore, it is necessary to select an appropriate capacitance of the first capacitor C1 based on the specific circumstances to achieve better filtering performance.

[0104] In summary, the first capacitor C1 can effectively remove high-frequency noise and ripple in the power supply signal, ensuring that the sampling chip 110 operates under stable power supply conditions, and increasing the accuracy and reliability of leakage current signal or other electrical signal detection.

[0105] In one embodiment, such as Figure 5 As shown, the sampling chip 110 includes a first signal output terminal OUT1, and the sampling chip 110 outputs a leakage signal through the first signal output terminal OUT1.

[0106] In this embodiment, the sampling chip 110 includes a first signal output terminal OUT1, which is used to output the detected leakage current signal. Specifically, when the sampling chip 110 detects leakage current on the current limiting circuit 120 through its sampling port, it will send out the corresponding leakage current signal through the first signal output terminal OUT1. These leakage current signals can be voltage signals, current signals, or other forms of electronic signals, depending on the circuit design and the output characteristics of the sampling chip 110.

[0107] Understandably, since the sampling chip 110 itself does not have the function of calculating leakage current, it only samples the leakage signal, such as the voltage drop across the current limiting circuit 120, and does not have the function of calculation. Therefore, in this embodiment, a signal output terminal needs to be added to output the leakage signal collected by the sampling chip 110, and to cooperate with the existing main control circuit or processing circuit in the existing system or existing circuit board for calculation and processing to determine the specific magnitude of the leakage current, so as to facilitate the subsequent implementation of corresponding measures.

[0108] Thus, by setting the first signal output terminal OUT1 in the sampling chip 110 to output the leakage signal, this embodiment can effectively transmit the leakage current information to the existing main control circuit or processing circuit on the system or circuit board, and perform relevant calculations on the leakage signal. This also benefits the miniaturization design of the power detection device and the circuit board using the power detection device.

[0109] like Figure 2 and Figure 3 As shown, this application also provides another embodiment of the power detection device 410. Specifically, the power detection device includes a first detection unit 200 and a second detection unit 300: the first detection unit 200 includes a first power input terminal, a first sampling chip 210 and a first current limiting circuit 220. The first sampling chip 210 has a first power terminal BAT2. The input terminal of the first current limiting circuit 220 is connected to the first power input terminal, and the output terminal of the first current limiting circuit 220 is connected to the power terminal of the first sampling chip 210; the second detection unit 300 is connected to the first current limiting circuit 220 and is used to collect the leakage current signal flowing through the first current limiting circuit 220.

[0110] It should be noted that in some more complex application scenarios, there may be more than one sampling chip on a circuit board. Importantly, not every sampling chip has an additional sampling port. It is possible that all the sampling ports of a certain sampling chip are used, so that the sampling chip does not have an additional sampling port to collect the leakage current signal on the corresponding current limiting circuit.

[0111] Therefore, in this embodiment, the power detection device 410 includes a first detection unit 200 and a second detection unit 300, each of which is an independent module. The first detection unit 200 includes a first power input terminal, a first sampling chip 210, and a first current limiting circuit 220. In this embodiment, the first sampling chip 210 does not have an additional sampling port, therefore the leakage current signal in the first detection unit 200 cannot be sampled by the first sampling chip 210. To address this, this embodiment proposes a second detection unit 300, which is connected to the first current limiting circuit 220 of the first detection unit 200 to sample the leakage current signal. Thus, even though the first sampling chip 210 does not have an additional sampling port, the second detection unit 300 can still detect the leakage current signal on the first current limiting circuit 220 of the first detection unit 200 through its own sampling port, ensuring that the leakage current of all detection units can be accurately monitored.

[0112] In one scenario: the first sampling chip 210 of the first detection unit 200 has no additional sampling ports, while the second detection unit 300 has four additional sampling ports. The first current limiting circuit 220 of the first detection unit 200 detects leakage current and generates a corresponding leakage signal. In the second detection unit 300, two sampling ports can be connected to the two ends of the current limiting circuit 120 of the first detection unit 200 to detect the leakage signal of the first detection unit 200. The other two sampling ports of the second detection unit 300 can be connected to the two ends of the first current limiting circuit 220 of another first detection unit 200, or they can be left unconnected to any detection unit. Alternatively, when the second detection unit 300 has the same structure as the first detection unit 200, they can be connected to the two ends of the current limiting circuit of the second detection unit 300 itself.

[0113] Furthermore, the components of the second detection unit 300 can be the same as those of the first detection unit 200, but the sampling chip of the second detection unit 300 has an additional sampling port. The second detection unit 300 can also be a separate third sampling chip, specifically designed to acquire the leakage current signal of the first detection unit 200.

[0114] When there are multiple first detection units 200 or second detection units 300, the connection method of the sampling ports between the detection units is not limited here. The important point is that the leakage signal of the first detection unit 200 can be detected by one second detection unit 300. In this way, even if the first sampling chip 210 does not have an additional sampling port, this application can still realize the detection of leakage signals of all first detection units 200.

[0115] Thus, in this embodiment, the second detection unit 300 performs leakage current detection on the first detection unit 200. The second detection unit 300 is also an existing device on the circuit board. In this way, even if some sampling chips do not have extra sampling ports, the power detection device of this embodiment can still detect the leakage current signal of all sampling chips without increasing the original size of the power detection device.

[0116] The following will explain two embodiments of the second detection unit 300. It should be noted that the explanation of the two embodiments of the second detection unit 300 in this application does not mean that the second detection unit 300 has only two embodiments.

[0117] In one embodiment, such as Figure 2 As shown, the second detection unit 300 includes a second power input terminal, a second sampling chip 311, and a second current limiting circuit 312. The second sampling chip 311 has a second power input terminal BAT3 and at least one set of first sampling ports, including a third acquisition terminal and a fourth acquisition terminal. The input terminal of the second current limiting circuit 312 is connected to the second power input terminal, and the output terminal of the second current limiting circuit 312 is connected to the second power input terminal BAT3 of the second sampling chip 311. The third acquisition terminal is connected to the input terminal of the first current limiting circuit 220, and the fourth acquisition terminal is connected to the output terminal of the first current limiting circuit 220. The second sampling chip 311 is used to acquire the leakage current signal flowing through the first current limiting circuit 220 through the third acquisition terminal and the fourth acquisition terminal.

[0118] It is understandable that the second sampling chip 311 of the second detection unit 300 can be understood as a sampling chip with an additional sampling port on the circuit board, so that even if the first sampling chip 210 does not have an additional sampling port, the second sampling chip 311 can detect the leakage signal on the first current limiting circuit 220 of the first detection unit 200 through its additional sampling port. Thus, it can be interpreted as using the second sampling chip 311 with an additional sampling port to detect the leakage signal of the first sampling chip 210 without an additional sampling port.

[0119] It should be noted that the second detection unit 300 has the same structure as the first detection unit 200, but it has an additional sampling port on top of the first detection unit 200. Therefore, in addition to detecting the leakage signal of the first detection unit 200, the second detection unit 300 can also perform the functions of the original sampling chip, such as processing analog signals. That is to say, the second sampling chip 311 is an existing chip in the circuit, originally used to solve other technical problems. However, in this embodiment, the additional sampling port of the second sampling chip 311 is used to detect the leakage signal. In this way, it avoids adding extra components to the circuit for detecting the leakage signal, which helps to miniaturize the power detection device and the circuit board using the power detection device.

[0120] Therefore, when there are multiple sampling chips on the circuit board, one sampling chip can be used to collect the leakage signal of another sampling chip, so that the leakage signal can be detected by existing components in the circuit board or the power detection device, thus avoiding increasing the size of the power detection device.

[0121] In the above embodiments, there are multiple second detection units 300. The second sampling chip 311 of at least one second detection unit 300 further includes at least one set of second sampling ports. The second sampling port includes a fifth acquisition terminal and a sixth acquisition terminal. The fifth acquisition terminal is connected to the input terminal of the second current limiting circuit 312 of the second detection unit 300, and the sixth acquisition terminal is connected to the output terminal of the second current limiting circuit 312 connected to the fifth acquisition terminal. The second sampling chip 311 is also used to acquire the leakage current signal flowing through the second current limiting circuit 312 through the fifth acquisition terminal and the sixth acquisition terminal.

[0122] Understandably, since the second detection unit 300 also has a second power input terminal, its second sampling chip 311 also needs to be used in the whole system, such as processing certain analog signals, etc. Therefore, the leakage signal of the second detection unit 300 also needs to be monitored and detected.

[0123] When there are multiple second detection units 300, these units can sample each other's leakage signals, thus ensuring that the leakage signal of each sampling chip can be monitored and detected. Furthermore, one or more of the multiple second detection units 300 also have a second sampling port. The second sampling port differs from the first sampling port in that the first sampling port is used to collect the leakage signal of the first detection unit 200, while the second sampling port is used to collect the leakage signal of the second detection unit 300. The second sampling port includes a fifth acquisition terminal and a sixth acquisition terminal. The leakage signal generated by the second current limiting circuit 312 is detected through the fifth and sixth acquisition terminals. This allows multiple second detection units 300 to not only collect their own leakage signals but also those of other second detection units 300, ensuring that the leakage current of each sampling chip can be accurately monitored.

[0124] In addition, each second detection unit 300 can be independent of each other or connected to each other to facilitate the detection of leakage signals between them.

[0125] In summary, the second detection unit 300 in this embodiment can detect the leakage signal of the first detection unit 200, its own leakage signal, and the leakage signals of other second detection units 300, ensuring that the leakage signal of each sampling chip is collected. Importantly, this second detection unit 300 is still an existing component on the circuit board using the power detection device. It can be a second detection unit 300 formed from a sampling chip whose sampling port is not fully utilized. Therefore, no additional components are added, which contributes to the miniaturization design of the power detection device and the circuit board using it.

[0126] In another embodiment, such as Figure 3 As shown, the second detection unit 300 includes a third sampling chip 321. The third sampling chip 321 has a third sampling port, which includes a seventh acquisition terminal and an eighth acquisition terminal. The seventh acquisition terminal of the third sampling port is connected to the input terminal of the first current limiting circuit 220, and the eighth acquisition terminal of the third sampling port is connected to the output terminal of the first current limiting circuit 220. The third sampling chip 321 is used to acquire the leakage current signal flowing through the first current limiting circuit 220 through the seventh acquisition terminal and the eighth acquisition terminal.

[0127] In this embodiment, the first sampling chips 210 of the first detection unit 200 are all sampling chips without additional sampling ports. In some cases, especially when the number of sampling ports of the sampling chips is limited, it may be that no sampling chip in the entire circuit has an additional sampling port, so it is impossible to directly detect the leakage current signal of each sampling chip. To solve this problem, a dedicated third sampling chip 321 can be introduced. Specifically, the third sampling chip 321 has a third sampling port for connecting to the first current limiting circuit 220 of the first detection unit 200, thereby collecting and detecting the leakage current signal of the first detection unit 200.

[0128] The number of the third sampling chips 321 can be multiple or one, and the number of third sampling ports in each third sampling chip 321 can be multiple or one.

[0129] It should be explained that the third sampling chip 321 can be a newly added third sampling chip, or it can be a sampling chip that is not used in the circuit.

[0130] On the one hand, regarding the newly added third sampling chip 321, it is understood that even though this embodiment uses the newly added third sampling chip 321 to collect the leakage current signal of the first detection unit 200, it can still achieve a miniaturized design compared to traditional power detection devices. Furthermore, in some exemplary power detection devices, a sampling circuit, a first control circuit, and a second control circuit are included. The first and second control circuits generate wake-up signals and fault signals based on the signals collected by the sampling circuit; thus, multiple additional control circuits are required in the circuit. However, the alarm signal or fault signal involved in this embodiment can be implemented using the control module in the battery management system, such as the BMU board. Therefore, additional control circuits are avoided, reducing the use of components and facilitating miniaturization. Moreover, the exemplary embodiment requires additional components to generate the corresponding leakage current signal and amplifies the leakage current signal by additionally setting up an amplification circuit. When the number of sampling chips is too large, the circuit becomes particularly complex and larger in size in order to detect the leakage current flowing into each sampling chip. In contrast, this embodiment only uses one third sampling chip 321, which can achieve efficient leakage current signal sampling even when the number of sampling chips is too large.

[0131] By using the third sampling chip 321 in this embodiment, we can effectively solve the problem of insufficient sampling ports of the sampling chip. Moreover, since only one third sampling chip 321 needs to be added, instead of a series of additional components, the area occupied by the circuit board can still be significantly reduced compared to traditional power detection devices.

[0132] On the other hand, regarding the case where the third sampling chip 321 can be a sampling chip, it can be a sampling chip that is not used in the original circuit or circuit board, or it can be an additional sampling chip. In this way, the third sampling chip 321 can perform other sampling chip operations while collecting leakage current, increasing the flexibility of the power detection device 410.

[0133] In one embodiment, there are multiple first detection units 200, and a second detection unit 300 is used to collect leakage current signals flowing through the first current limiting circuit 220 of at least one first detection unit 200; or, there are multiple first detection units 200 and multiple second detection units 300, and each second detection unit 300 collects leakage current signals flowing through the first current limiting circuit 220 of at least one first detection unit 200.

[0134] In this embodiment, when there are multiple first detection units 200 on the circuit board, the leakage current signal of each first detection unit 200 can be collected by one or more second detection units 300. Specifically, if there is only one second detection unit 300, the second detection unit 300 can collect the leakage current signal on the first current limiting circuit 220 of at least one first detection unit 200.

[0135] In this embodiment, if there are multiple second detection units 300 on the circuit board, each second detection unit 300 can collect the leakage current signal from the first current limiting circuit 220 of at least one first detection unit 200. This allows the leakage current of all first detection units 200 to be detected when needed.

[0136] This embodiment uses multiple second detection units 300 to detect leakage current of multiple first detection units 200, ensuring that the leakage signals of all sampling chips in the circuit can be accurately detected. Moreover, the number of second detection units 300 can be flexibly configured according to actual conditions, which helps to miniaturize the circuit board design and also reduces costs.

[0137] In one embodiment, such as Figure 2 and Figure 3 As shown, the first current limiting circuit 220 includes a second resistor R2. The first end of the second resistor R2 is connected to the first power input terminal, and the second end of the second resistor R2 is connected to the first power supply terminal BAT2 of the first sampling chip 210. Furthermore, when leakage current exists at the first power input terminal, this leakage current will flow through the second resistor R2 to the first power supply terminal BAT2 of the first sampling chip 210. The second resistor R2 not only serves to limit current but also allows for indirect detection of leakage current by detecting the voltage drop across it.

[0138] By using the second resistor R2, this embodiment can effectively convert leakage current into a detectable voltage drop. When leakage current exists, a voltage drop proportional to the leakage current will be generated across the second resistor R2. By detecting this voltage drop, the magnitude of the leakage current can be calculated. Moreover, the second resistor R2 is an existing component in the circuit, originally used for current limiting, but in this embodiment it is also used to generate the corresponding leakage signal, avoiding the need to add components to generate the leakage signal, simplifying the circuit design, and facilitating the miniaturization of the power supply detection device.

[0139] In one embodiment, such as Figure 2 and Figure 3 As shown, the first detection unit 200 also includes a first filtering circuit 230, which is connected to the output terminal of the first current limiting circuit 220 and the first power supply terminal BAT2 of the first sampling chip 210, and is used to filter the power signal input to the first sampling chip 210.

[0140] It is understood that the first filter circuit 230 is connected between the output terminal of the first current limiting circuit 220 and the first power supply terminal BAT2 of the first sampling chip 210. Its purpose is to filter the power signal input to the first sampling chip 210 to remove high-frequency noise and other interference signals in the power signal and improve the quality of the power signal.

[0141] In this embodiment, the first filtering circuit 230 can select an appropriate filter type, such as a low-pass filter, high-pass filter, or band-pass filter, according to actual application requirements to meet specific frequency response requirements. Furthermore, the first filtering circuit 230 can be composed of components such as capacitors and inductors, effectively filtering out high-frequency noise and other interference signals, improving power supply stability. This ensures that the sampling chip operates under stable power conditions, increasing the accuracy and reliability of leakage current signal or other electrical signal detection.

[0142] In one embodiment, the first filter circuit 230 includes a second capacitor C2. The first end of the second capacitor C2 is connected to the output end of the first current limiting circuit 220 and the first power supply terminal BAT2 of the first sampling chip 210. The second end of the second capacitor C2 is grounded.

[0143] In this embodiment, the first filter circuit 230 employs a simple low-pass filter design, which effectively filters out high-frequency noise and ripple, ensuring that the power signal received by the sampling chip is purer and more stable. Thus, the second capacitor C2 can effectively remove high-frequency noise and ripple from the power signal, ensuring that the sampling chip operates under stable power conditions and increasing the accuracy and reliability of leakage current signal or other electrical signal detection.

[0144] In other embodiments, other components, such as inductors and resistors, can be used to form other types of filters. The specific filter structure can be determined according to the actual application.

[0145] In one embodiment, such as Figure 2 As shown, the second current limiting circuit 312 includes a third resistor R3. The first end of the third resistor R3 is connected to the second power input terminal, and the second end of the third resistor R3 is connected to the second power input terminal BAT3 of the second sampling chip 311.

[0146] Furthermore, when leakage current exists, it flows through the third resistor R3 to the second power supply terminal BAT3 of the second sampling chip 311. The third resistor R3 not only limits the current but also allows the leakage current to be indirectly detected by detecting the voltage drop across it. Thus, by using the third resistor R3 as the second current-limiting circuit 312, this embodiment can effectively convert the leakage current into a detectable voltage drop. When leakage current exists, a voltage drop proportional to the leakage current will be generated across the third resistor R3. By detecting this voltage drop through the third and fourth acquisition terminals of the second sampling chip 311, the magnitude of the leakage current can be calculated.

[0147] It is understandable that the third resistor R3 is an existing component in the circuit, originally used for current limiting. However, in this embodiment, it is also used to generate the corresponding leakage signal, avoiding the need to add components to generate the leakage signal, simplifying the circuit design, and facilitating the miniaturization design of the power supply detection device.

[0148] In one embodiment, such as Figure 2 As shown, the second detection unit 300 also includes a second filtering circuit 313, which is connected to the output terminal of the second current limiting circuit 312 and the second power supply terminal BAT3 of the second sampling chip 311, and is used to filter the power signal input to the second sampling chip 311.

[0149] It is understood that the second filter circuit 313 is connected between the output terminal of the second current limiting circuit 312 and the second power supply terminal BAT3 of the second sampling chip 311. Its purpose is to filter the power signal input to the second sampling chip 311. Specifically, the second filter circuit 313 can remove corresponding frequency noise and ripple in the power signal. In this way, the quality of the power signal received by the second sampling chip 311 can be significantly improved, ensuring that the sampling chip works under stable power conditions and increasing the accuracy and reliability of leakage current signal or other electrical signal detection.

[0150] In this embodiment, the second filter circuit 313 can select a suitable filter type, such as a low-pass filter, a high-pass filter, or a band-pass filter, according to actual application requirements to meet specific frequency response requirements. Furthermore, the second filter circuit 313 can be composed of components such as capacitors and inductors, effectively filtering out interference signals and improving power supply stability.

[0151] In one embodiment, such as Figure 2 As shown, the second filter circuit 313 includes a third capacitor C3. The first terminal of the third capacitor C3 is connected to the output terminal of the second current limiting circuit 312 and the second power supply terminal BAT3 of the second sampling chip 311, while the second terminal of the third capacitor C3 is grounded. Thus, the second filter circuit 313 employs a simple low-pass filter design, implemented using the third capacitor C3. The first terminal of the third capacitor C3 is connected to the output terminal of the second current limiting circuit 312 and the second power supply terminal BAT3 of the second sampling chip 311, while the second terminal of the third capacitor C3 is grounded. This design effectively filters out high-frequency noise and ripple, ensuring that the power signal received by the second sampling chip 311 is purer and more stable.

[0152] In some practical applications, the selection of the third capacitor C3 needs to consider the frequency characteristics of the power supply signal and the operating requirements of the sampling chip. Generally, a larger capacitance of the third capacitor C3 results in better filtering, but it may also introduce greater phase delay. Therefore, it is necessary to select a third capacitor C3 with an appropriate capacitance based on the specific circumstances to achieve the best filtering effect.

[0153] In one embodiment, such as Figure 6 and Figure 7 As shown, when the number of second detection units 300 is one, the second detection unit 300 further includes a second signal output terminal OUT2, through which the second detection unit 300 outputs a leakage current signal; and as shown Figure 8 As shown, when there are multiple second detection units 300, the output terminal of the previous second detection unit 300 is connected to the input terminal of the next second detection unit 300, and the last second detection unit 300 includes a third signal output terminal OUT3. Multiple second detection units 300 output leakage signals through the third signal output terminal OUT3.

[0154] In this embodiment, different signal output schemes are designed according to the number of second detection units 300 to ensure that leakage signals can be correctly output and processed.

[0155] In the case of only one second detection unit 300, the second detection unit 300 includes a second signal output terminal OUT2, which is used to output the leakage current signal collected by the second detection unit 300; since there is only one second detection unit 300, the leakage current signal is directly output from the second signal output terminal OUT2.

[0156] In the case of multiple second detection units 300, the output of one second detection unit 300 is connected to the input of the next second detection unit 300. This daisy-chain connection allows the leakage current signal to be transmitted sequentially from the first second detection unit 300 to the last second detection unit 300. The last second detection unit 300 includes a third signal output terminal OUT3, which is used to collect the leakage current signals collected by all the second detection units 300 and output these signals.

[0157] Understandably, since the sampling chip itself does not have the function of calculating leakage current, it only samples the leakage signal, such as the voltage drop across the current limiting circuit, and does not have the function of calculation. Therefore, in this embodiment, a signal output terminal needs to be added to output the leakage signal collected by the sampling chip, and to cooperate with the existing main control circuit or processing circuit in the existing system or existing circuit board to perform calculation and processing to determine the specific magnitude of the leakage current, so as to facilitate the subsequent implementation of corresponding measures.

[0158] Thus, with a single second detection unit 300, the leakage signal is directly output from the second signal output terminal OUT2, resulting in a simple structure that is easy to implement. With multiple second detection units 300, the output is routed in a daisy-chain configuration, simplifying circuit wiring. Overall, this approach facilitates miniaturization while ensuring accurate acquisition and output of the leakage signal.

[0159] This application also proposes a sampling circuit board, which includes a circuit board and the aforementioned power detection device 410, which is integrated into the circuit board.

[0160] It should be noted that the sampling circuit board includes a circuit board and a power detection device 410. The specific structure of the power detection device 410 is as described in the above embodiments. Since this sampling circuit board adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0161] Understandably, sampling circuit boards, such as CSC boards, are part of the battery management system and are used to monitor key parameters such as battery cell voltage, temperature, and current. The power detection device 410 is integrated on the circuit board to detect the leakage current of the sampling chip. This circuit utilizes unused sampling ports on the sampling chip and the voltage drop across the current-limiting resistor to monitor the leakage current. Thus, no additional hardware components are required, significantly reducing the space occupied by the circuit board and contributing to the miniaturization of the sampling circuit board design.

[0162] This application also proposes a battery management system, such as Figure 4 As shown, the battery management system includes a control module 500 and a sampling module 400. Since the battery management system includes a sampling module 400, which includes a sampling circuit board, and the specific structure of the sampling circuit board is as described in the above embodiments, this battery management system adopts all the technical solutions of all the above embodiments, and therefore has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here. The control module 500 is connected to the sampling module 400, and the control module 500 is used to receive the signal output by the sampling module 400.

[0163] In this embodiment, the specific structure of the sampling module 400 is the same as in the previously described embodiment, and includes the design of a power detection device 410. This circuit utilizes unused sampling ports on the sampling chip to detect leakage current without adding additional hardware components. The control module 500 is connected to the sampling module 400 and is mainly used to receive signals output by the sampling module 400 and perform corresponding processing and decisions based on these signals. Furthermore, the output terminal of the sampling module 400 can be connected to the input terminal of the control module 500. The sampling module 400 transmits the signals it collects to the control module 500, such as battery monitoring signals and the aforementioned leakage current signals; and the control module 500 analyzes or calculates these signals using its existing processor or controller to obtain the corresponding leakage current magnitude for the leakage current signal.

[0164] Understandably, the sampling module 400 samples the leakage signal using existing components, while the control module 500 calculates the collected leakage signal to determine the corresponding leakage current magnitude. Thus, not only does the leakage current detection process of the sampling module 400 not require additional components, but the battery management system's leakage current calculation also does not require additional components. Consequently, the entire battery management system utilizes no additional components for leakage current detection and calculation, which is beneficial for the miniaturization of the entire system.

[0165] In summary, this battery management system, without adding any components, collects and calculates the leakage current signal of the AFE chip, thereby improving the reliability of the entire system.

[0166] In one embodiment, such as Figure 4 as well as Figures 5 to 8 As shown, Figure 4 This is a diagram of the overall structure. Figures 5 to 8 For further circuit structure diagram, the sampling module 400 has a signal output terminal, and the sampling module 400 outputs a leakage current signal through the signal output terminal. The control module 500 has a main control circuit 510; the input terminal of the main control circuit 510 is connected to the signal output terminal of the sampling module 400, and the output terminal of the main control circuit 510 is connected to the power consumption device 600; the main control circuit 510 is used to receive the leakage current signal output by the power detection device 410, and control the power consumption device 600 to perform corresponding operations according to the leakage current signal.

[0167] It's important to explain that in the architecture of a battery management system, the sampling module 400 and the control module 500 typically have different responsibilities. The sampling module 400 is primarily responsible for monitoring key parameters of the battery cells, such as voltage, temperature, and current, and transmitting this data to the control module 500 for further processing and analysis. The sampling module 400 usually does not contain complex logic processing capabilities, but focuses on data acquisition and simple signal processing. Therefore, the sampling module 400 may contain some simple control logic, but it usually does not contain a complete main control circuit 510, as complex logic processing and decision-making are typically handled by the control module 500. The control module 500 is responsible for overall management and decision-making. The control module 500 typically contains a main control circuit 510 (usually a microprocessor or microcontroller), which receives data from the sampling module 400 and makes decisions based on this data, such as adjusting charging and discharging strategies and activating early warning mechanisms.

[0168] Therefore, in this embodiment, no additional control chip is added to the sampling module 400 to process the leakage signal. Instead, the leakage signal collected by the sampling module 400 is input to the main control circuit 510 of the control module 500 for relevant processing. Specifically, the sampling module 400 has a signal output terminal for outputting the detected leakage signal. The control module 500 is equipped with a main control circuit 510, the input terminal of which is connected to the signal output terminal of the sampling module 400 to receive the leakage signal and calculate the corresponding leakage current based on the leakage signal; its output terminal is connected to the electrical device 600 (such as the control system of an electric vehicle). The main control circuit 510 is responsible for taking corresponding control measures based on the received leakage signal to ensure the safe operation of the system.

[0169] In this embodiment, the leakage current signal can be integrated and output through the first signal output terminal OUT, the second signal output terminal OUT2, and the third signal output terminal OUT3 mentioned above.

[0170] In this embodiment, the electrical control device 600 performs corresponding operations based on the leakage signal. When the leakage signal indicates that the leakage current exceeds a preset value, the operation may be to output a corresponding alarm signal, suspend operation, or take corresponding measures to deal with the leakage signal.

[0171] Thus, by combining the power detection device 410 with the control module 500, this embodiment not only improves the system's integration and reliability, but also effectively monitors leakage current, reduces system costs, and helps to achieve miniaturized design of the sampling module 400 and the battery management system. It also ensures the efficient and safe operation of the entire battery management system in electric vehicles or hybrid vehicles.

[0172] In one embodiment, such as Figures 4 to 8 As shown, the control module 500 integrates a comparator circuit 511, which has a first signal input terminal and a second signal input terminal. The first signal input terminal of the comparator circuit 511 is connected to the signal output terminal of the CSC board 400, and the second signal input terminal of the comparator circuit 511 is connected to a current reference signal. The comparator circuit 511 is used to compare the leakage current signal with the current reference signal, and outputs a first comparison signal when the current value corresponding to the leakage current signal is greater than the current value corresponding to the current reference signal. The control module 500 is used to determine the power supply leakage based on the first comparison signal and control the electrical device 600 to issue a corresponding alarm signal.

[0173] In this embodiment, the control module 500 integrates a comparison circuit 511. The comparison circuit 511 compares the magnitude of the leakage current signal and its task is to compare the two signals. If the current value corresponding to the leakage current signal is greater than the current value corresponding to the current reference signal, a first comparison signal is output. After receiving the first comparison signal, the control module 500 determines that a power supply leakage has occurred and controls the electrical device 600 (such as an electric vehicle) to issue a corresponding alarm signal.

[0174] Understandably, this current reference signal is a threshold. When the detected leakage current exceeds this threshold, it proves that the leakage current will affect the operation of the system, and therefore corresponding measures need to be taken.

[0175] In this embodiment, a corresponding alarm signal is issued when leakage occurs. This alarm signal can be issued directly through the electrical device 600 to notify the user so that the user can take corresponding measures; the alarm signal can also be used to trigger the internal protection program of the electrical device 600, such as parameter adjustment or switch control; the alarm signal can also be uploaded to the cloud through the communication system of the electrical device 600, and then the back-end personnel can handle the leakage signal in a timely manner to prevent the user from noticing the existence of leakage current and to ensure the user's experience.

[0176] Understandably, by setting a current reference signal, the false alarm rate can be effectively reduced, unnecessary false alarms can be avoided, and the reliability of the system can be improved.

[0177] Thus, once a leakage signal is detected exceeding the set threshold, the system will automatically activate the early warning mechanism, promptly upload data to the cloud server for analysis, or take other preventative maintenance measures to ensure the reliability of the battery management system.

[0178] In one embodiment, the control module 500 integrates a first comparator and a second comparator; one signal input terminal of the first comparator is connected to the signal output terminal of the sampling module, and the other signal input terminal of the first comparator is connected to a first current reference signal; the first comparator compares the leakage signal with the first current reference signal, and outputs a second comparison signal when the current value corresponding to the leakage signal is greater than the current value corresponding to the first current reference signal; one signal input terminal of the second comparator is connected to the signal output terminal of the sampling module, and the other signal input terminal of the second comparator is connected to the second current reference signal; the second comparator compares the leakage signal with the second current reference signal, and outputs a third comparison signal when the current value corresponding to the leakage signal is greater than the current value corresponding to the second current reference signal; the first comparator operates when the sampling chip in the corresponding sampling circuit board is in standby mode; the second comparator operates when the sampling chip in the corresponding sampling circuit board is in working mode; the control module 500 determines power leakage based on the second comparison signal and / or the third comparison signal, and controls the electrical device 600 to issue a corresponding alarm signal.

[0179] Understandably, the control module 500 incorporates two comparators with different current reference signals to distinguish and respond to current anomalies in the sampling chip under different operating states. In this embodiment, one end of the first comparator is connected to the first current reference signal; the other end of the second comparator is connected to the second current reference signal. It should be explained that the first current reference signal is set as the upper limit of the normal current range of the sampling chip in standby mode. If the current value exceeds this threshold in standby mode, it may indicate leakage or other abnormalities. The second current reference signal is set as the upper limit of the normal current range of the sampling chip in operating mode. In operating mode, the sampling chip typically consumes more current, therefore this threshold is higher than the threshold in standby mode. When the current exceeds this value in operating mode, it also indicates a possible overload or other fault.

[0180] In this embodiment, when the sampling chip is in standby mode, the first comparator starts working. If the first comparator detects a current value exceeding the first current reference signal, it generates a second comparison signal, triggering the power-consuming device 600 or the alarm circuit to output alarm information. Similarly, when the sampling chip is in working mode, the second comparator starts working. If the second comparator detects a current value exceeding the second current reference signal, it generates a third comparison signal, triggering the power-consuming device 600 or the alarm circuit to output alarm information.

[0181] By distinguishing between standby and operating modes, the system can more accurately identify when current anomalies occur, avoiding false alarms and ensuring that appropriate alarms are triggered at the correct times. Thus, by setting current reference signals for different operating states of the sampling chip, the system can monitor the current consumption of the sampling chip more intelligently and accurately. This not only improves the system's energy efficiency and safety but also optimizes fault diagnosis and maintenance processes, thereby enhancing the overall performance of power equipment and the user experience.

[0182] In one embodiment, the electrical device 600 is a vehicle, including but not limited to electric vehicles, hybrid vehicles, plug-in hybrid vehicles, etc.

[0183] The following explanation addresses the aforementioned application scenarios: To ensure stable operation of the sampling circuit in the vehicle's sampling circuit board under different operating modes, corresponding leakage current thresholds are set. For example, in standby mode, the leakage current should be less than 220 microamps, while in operating mode, the leakage current threshold is relaxed to less than 10 milliamps. The sampling chip transmits the measured voltage data across the detection resistor to the control module 500 via daisy-chain communication. The control module 500 further processes this data to determine the actual leakage current of the sampling chip and, based on the current operating mode of the sampling chip, judges whether the leakage current exceeds the preset safety range. Once it is detected that the leakage current of the sampling chip exceeds the standard, the control module 500 will upload this abnormality to the vehicle's VCU (Vehicle Control Unit) via the CAN bus. The vehicle VCU then synchronizes the alarm information to the background database, realizing early warning of potential faults, thereby ensuring the safety and reliability of electric vehicle operation. This ensures the stable operation of the vehicle in complex environments and also provides important data support for maintenance and fault diagnosis.

[0184] The above description is merely an exemplary embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the technical concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A power supply detection device, characterized in that, The power detection device includes: Power input terminal; The sampling chip has a power supply terminal, a first acquisition terminal, and a second acquisition terminal; A current limiting circuit, wherein the input terminal of the current limiting circuit is connected to the power input terminal, and the output terminal of the current limiting circuit is connected to the power supply terminal of the sampling chip; The first acquisition terminal is connected to the input terminal of the current limiting circuit, and the second acquisition terminal is connected to the output terminal of the current limiting circuit; The sampling chip is used to collect the leakage current signal flowing through the current limiting circuit through the first acquisition terminal and the second acquisition terminal.

2. The power supply detection device as described in claim 1, characterized in that, The current limiting circuit includes a first resistor, with a first end connected to the power input terminal and a second end connected to the power supply terminal of the sampling chip.

3. The power supply detection device as described in claim 1, characterized in that, The power detection device further includes a filtering circuit, which is connected to the output terminal of the current limiting circuit and the power supply terminal of the sampling chip, and is used to filter the power signal input to the sampling chip.

4. The power supply detection device as described in claim 3, characterized in that, The filtering circuit includes a first capacitor, the first end of which is connected to the output terminal of the current limiting circuit and the power supply terminal of the sampling chip, and the second end of the first capacitor is grounded.

5. The power supply detection device according to any one of claims 1 to 4, characterized in that, The sampling chip includes a first signal output terminal, through which the leakage signal is output.

6. A power supply detection device, characterized in that, The power detection device includes: The first detection unit includes a first power input terminal, a first sampling chip, and a first current limiting circuit. The first sampling chip has a first power terminal, the input terminal of the first current limiting circuit is connected to the first power input terminal, and the output terminal of the first current limiting circuit is connected to the power terminal of the first sampling chip. The second detection unit is connected to the first current limiting circuit and is used to collect the leakage current signal flowing through the first current limiting circuit.

7. The power detection device as described in claim 6, characterized in that, The second detection unit includes a second power input terminal, a second sampling chip, and a second current limiting circuit. The second sampling chip has a second power input terminal and at least one set of first sampling ports, the first sampling ports including a third acquisition terminal and a fourth acquisition terminal. The input terminal of the second current limiting circuit is connected to the second power input terminal, and the output terminal of the second current limiting circuit is connected to the second power input terminal of the second sampling chip. The third acquisition terminal is connected to the input terminal of the first current limiting circuit, and the fourth acquisition terminal is connected to the output terminal of the first current limiting circuit. The second sampling chip is used to collect the leakage current signal flowing through the first current limiting circuit through the third and fourth acquisition terminals.

8. The power detection device as described in claim 6, characterized in that, The second detection unit includes a third sampling chip, which has a third sampling port. The third sampling port includes a seventh acquisition terminal and an eighth acquisition terminal. The seventh acquisition terminal of the third sampling port is connected to the input terminal of the first current limiting circuit, and the eighth acquisition terminal of the third sampling port is connected to the output terminal of the first current limiting circuit. The third sampling chip is used to collect the leakage current signal flowing through the first current limiting circuit through the seventh and eighth acquisition terminals.

9. The power supply detection device according to any one of claims 6 to 8, characterized in that, The first detection unit may be multiple, and the second detection unit is used to collect the leakage current signal flowing through the first current limiting circuit of at least one of the first detection units; or, There are multiple first detection units and multiple second detection units. Each second detection unit collects at least one leakage current signal flowing through the first current limiting circuit of the first detection unit.

10. The power supply detection device according to any one of claims 6 to 8, characterized in that, The first current limiting circuit includes a second resistor, the first end of which is connected to the first power input terminal, and the second end of which is connected to the first power supply terminal of the first sampling chip.

11. The power supply detection device according to any one of claims 6 to 8, characterized in that, The first detection unit further includes a first filtering circuit, which includes a second capacitor. The first end of the second capacitor is connected to the output end of the first current limiting circuit and the first power supply end of the first sampling chip, and the second end of the second capacitor is grounded.

12. The power detection device as described in claim 7, characterized in that, The second current limiting circuit includes a third resistor, the first end of which is connected to the second power input terminal, and the second end of which is connected to the second power supply terminal of the second sampling chip.

13. The power detection device as described in claim 7, characterized in that, The second detection unit further includes a second filtering circuit, which includes a third capacitor. The first end of the third capacitor is connected to the output end of the second current limiting circuit and the second power supply end of the second sampling chip, and the second end of the third capacitor is grounded.

14. The power supply detection device according to any one of claims 6 to 8, characterized in that, When there is only one second detection unit, the second detection unit further includes a second signal output terminal, and the second detection unit outputs the leakage signal through the second signal output terminal; When there are multiple second detection units, the output terminal of the previous second detection unit is connected to the input terminal of the next second detection unit, and the last second detection unit includes a third signal output terminal. The multiple second detection units output the leakage signal through the third signal output terminal.

15. A sampling circuit board, characterized in that, The sampling circuit board includes: Circuit board; The power detection device as described in any one of claims 1 to 14, wherein the power detection device is integrated into the circuit board.

16. A battery management system, characterized in that, The battery management system includes: The sampling module includes the sampling circuit board as described in claim 15; A control module, the input terminal of which is connected to the signal output terminal of the sampling circuit board, is used to receive the signal output by the sampling module.

17. The battery management system as described in claim 16, characterized in that, The sampling module has a signal output terminal, and the sampling module outputs a leakage current signal through the signal output terminal; The input terminal of the control module is connected to the signal output terminal of the sampling module, and the output terminal of the control module is connected to the electrical device. The control module is used to receive the leakage current signal output by the sampling module and control the electrical device to perform corresponding operations based on the leakage current signal.

18. The battery management system as described in claim 17, characterized in that, The control module integrates a comparator circuit, which has a first signal input terminal and a second signal input terminal. The first signal input terminal of the comparator circuit is connected to the signal output terminal of the sampling module, and the second signal input terminal of the comparator circuit is connected to a current reference signal. The comparison circuit is used to compare the leakage signal with the current reference signal, and output a first comparison signal when the current value corresponding to the leakage signal is greater than the current value corresponding to the current reference signal. The control module is used to determine power leakage based on the first comparison signal and control the electrical device to issue a corresponding alarm signal.

19. The battery management system as described in claim 17, characterized in that, The control module integrates a first comparator and a second comparator. One signal input terminal of the first comparator is connected to the signal output terminal of the sampling circuit board, and the other signal input terminal of the first comparator is connected to a first current reference signal; the first comparator compares the leakage signal with the first current reference signal, and outputs a second comparison signal when the current value corresponding to the leakage signal is greater than the current value corresponding to the first current reference signal. One signal input terminal of the second comparator is connected to the signal output terminal of the sampling circuit board, and the other signal input terminal of the second comparator is connected to the second current reference signal; The second comparator is used to compare the leakage signal with the second current reference signal, and output a third comparison signal when the current value corresponding to the leakage signal is greater than the current value corresponding to the second current reference signal; When the sampling chip in the sampling circuit board is in standby mode, the first comparator operates; when the sampling chip in the sampling circuit board is in operating mode, the second comparator operates. The control module determines power leakage based on the second comparison signal and / or the third comparison signal, and controls the electrical device to issue a corresponding alarm signal.

Images