CN-122017630-A - Safety verification method, device, equipment and medium for double-current sampling of energy storage system

CN122017630ACN 122017630 ACN122017630 ACN 122017630ACN-122017630-A

Abstract

The application provides a safety verification method, device, equipment and medium for double-current sampling of an energy storage system, which comprises the steps of arranging a first current detection part at the positive end of a battery in a battery heating loop and at the position outside the heating loop, arranging a second current detection part at the position of the negative end of the battery, determining heating loop current based on a first current sampling signal of the first current detection part and a second current sampling signal of the second current detection part acquired in real time, carrying out battery heating loop state monitoring and fault diagnosis based on the heating loop current, and carrying out frequency domain harmonic energy distribution consistency judgment and time domain steady state current deviation analysis on the first current sampling signal and the second current sampling signal to determine abnormality of the current detection part and dynamically select a main loop current value. The mutual calibration of double current sampling is realized, the reliability and functional safety of the system are improved, and the number of hardware current sampling is not increased.

Inventors

ZENG FANWEI
MOU JIAN
ZOU HUIXING

Assignees

上海派能能源科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260401

Claims (10)

1. The safety verification method for double-current sampling of the energy storage system is characterized by comprising the following steps of: a first current detecting part is arranged at the positive end of the battery in the battery heating loop and at a position outside the heating loop, and a second current detecting part is arranged at the negative end of the battery; Determining a heating loop current based on a first current sampling signal of the first current detection component and a second current sampling signal of the second current detection component which are acquired in real time, and performing battery heating loop state monitoring and fault diagnosis based on the heating loop current; And carrying out frequency domain harmonic energy distribution consistency judgment and time domain steady-state current deviation analysis on the first current sampling signal and the second current sampling signal to determine the abnormality of the current detection component and dynamically select the main loop current value.
2. The safety verification method according to claim 1, wherein determining a heating loop current based on the first current sampling signal of the first current detection part and the second current sampling signal of the second current detection part acquired in real time, and performing battery heating loop state monitoring and fault diagnosis based on the heating loop current, comprises: determining the heating loop current based on the first current sampling signal and the second current sampling signal; when a voltage exists between the anode and the cathode of the battery and the heating MOS tube is in a closed state, if the current of the heating loop is in a fault preset range, determining an open circuit fault of the heating loop; when a voltage exists between the anode and the cathode of the battery and the heating MOS tube is in a closed state, if the deviation between the resistance value of the heating resistor calculated based on ohm law and the rated resistance value exceeds a threshold value, determining that the heating resistance value of the battery heating loop has abnormal faults; When a voltage exists between the anode and the cathode of the battery and the heating MOS tube is in a closed state, and the current of the heating loop is in a preset normal range, if the actually measured temperature rise rate is lower than an expected threshold value, determining that the heating film falls off; and when the heating MOS tube receives a disconnection instruction or is in a disconnection state, the heating loop current is still continuously greater than zero, and the adhesion fault of the heating MOS tube is determined.
3. The method of claim 1, wherein said performing a frequency domain harmonic energy distribution uniformity determination and a time domain steady state current bias analysis on said first current sample signal and said second current sample signal, determining anomalies in the current detection component and dynamically selecting the main loop current value, comprises: performing frequency component analysis and direct current component extraction on the first current sampling signal and the second current sampling signal to determine a first basic frequency of the first current sampling signal, a first direct current and a second basic frequency and a second direct current of the second current sampling signal; Based on the first basic frequency and the second basic frequency, carrying out frequency domain harmonic energy distribution consistency judgment, and determining the abnormality of the current detection component; and carrying out time domain steady state current deviation analysis based on the first direct current and the second direct current, and dynamically selecting the main loop current value.
4. The security verification method according to claim 3, wherein the determining of the abnormality of the current detection means based on the frequency domain harmonic energy distribution consistency determination by the first base frequency and the second base frequency includes: Determining the energy proportion of the first fundamental frequency and the second fundamental frequency in the integral fluctuation component; Comparing the component energy proportion of the first basic frequency with the component energy proportion of the second basic frequency, and determining that the current detection component corresponding to the lower component energy proportion works abnormally when any component energy proportion is lower than the other component energy proportion and the difference reaches or exceeds a preset proportion threshold value.
5. A security verification method according to claim 3, wherein said dynamically selecting said main loop current value based on said first dc current and said second dc current for time-domain steady state current bias analysis comprises: When any current detection component is abnormal, detecting whether the heating MOS tube is in an off state or not; If so, determining estimated current which should flow in the main loop based on the current state of charge, temperature and terminal voltage and internal resistance characteristics of the battery in a static state; and performing time domain steady-state current deviation analysis based on the first direct current, the second direct current and the estimated current, and selecting the main loop current value according to the relation between the directionality and the relative amplitude of the deviation.
6. The method of claim 5, wherein the performing a time-domain steady-state current bias analysis based on the first dc current, the second dc current, and the predicted current, and selecting the main loop current value based on a directionality-relative-amplitude relationship of the bias, comprises: Comparing the first direct current and the second direct current with the estimated current respectively; If the first direct current and the second direct current are close to the estimated current, or the first direct current and the second direct current deviate in the same direction relative to the estimated current and the deviation degree is in a preset deviation range, taking the average value of the first direct current and the second direct current as the main loop current value; If the condition is not met, selecting the direct current which is closer to the estimated current from the first direct current and the second direct current as the main loop current value.
7. The method of claim 1, wherein the battery heating circuit comprises a battery, a charging MOS tube, a discharging MOS tube, a heating MOS tube, an energy management system and a heating resistor, wherein, The negative electrode end of the battery is electrically connected with the drain electrode of the charging MOS tube, the source electrode of the charging MOS tube is electrically connected with the drain electrode of the discharging MOS tube, the source electrode of the discharging MOS tube is electrically connected with the first end of the heating resistor, the second end of the heating resistor is electrically connected with the drain electrode of the heating MOS tube, and the source electrode of the heating MOS tube is electrically connected with the positive electrode end of the battery; and the grid electrodes of the charging MOS tube, the discharging MOS tube and the heating MOS tube are electrically connected with the energy management system.
8. The utility model provides a safety check device of energy storage system double current sampling which characterized in that, safety check device includes: a setting module for setting a first current detection part at the positive end of the battery in the battery heating circuit and at a position outside the heating circuit, and setting a second current detection part at the negative end of the battery; The double-current first detection module is used for determining a heating loop current based on a first current sampling signal of the first current detection component and a second current sampling signal of the second current detection component which are acquired in real time, and performing battery heating loop state monitoring and fault diagnosis based on the heating loop current; And the double-current second detection module is used for judging the consistency of frequency domain harmonic energy distribution and analyzing the time domain steady-state current deviation of the first current sampling signal and the second current sampling signal, and determining the abnormality of the current detection component and dynamically selecting the current value of the main loop.
9. An electronic device comprising a processor, a memory and a bus, the memory storing machine readable instructions executable by the processor, the processor and the memory in communication via the bus when the electronic device is in operation, the machine readable instructions being executable by the processor to perform the steps of the method for double current sampling of an energy storage system according to any one of claims 1 to 7.
10. A computer readable storage medium, characterized in that the computer readable storage medium has stored thereon a computer program which, when executed by a processor, performs the steps of the method for safety verification of dual current sampling of an energy storage system according to any one of claims 1 to 7.

Description

Safety verification method, device, equipment and medium for double-current sampling of energy storage system Technical Field The application relates to the technical field of energy storage systems, in particular to a safety verification method, device, equipment and medium for double-current sampling of an energy storage system. Background Currently, a single current sampling architecture is generally adopted in a mainstream energy storage system, namely a single current sensor (such as a current detection resistor, a Hall sensor or a fluxgate sensor) is arranged in a battery main loop, and core functions such as SOC estimation, charge and discharge control, overcurrent/short circuit protection and the like are realized by collecting the current value of the point. The architecture has inherent defects that once the sampling precision of the current sensor is misaligned due to temperature drift, aging, magnetic core saturation or PCB wiring interference, SOC accumulated deviation and capacity statistical distortion are directly caused, and the protection function of the current-related software is caused to malfunction (such as no fault charge) or refused to act (such as overcurrent and no cutting off), so that the system safety is seriously threatened. To improve the reliability of thermal management, an independent heating loop is added to a part of the energy storage system in the alpine region, and the independent heating loop is generally composed of a heating film, a heating loop switching device (such as a MOSFET) and a special current sampling unit. In the traditional scheme, a current sensor is additionally arranged for monitoring the current of the heating loop, so that fault diagnosis of a heating open circuit, abnormal resistance and the like is realized. However, the design brings triple contradiction that (1) the hardware cost is increased, each BMS needs one more high-precision current sensor and matched signal conditioning circuit, and (2) the fault diagnosis dimension is single, the existing heating fault criterion is more dependent on steady-state current amplitude or simple threshold comparison, and the heating film is difficult to identify local falling-off. Therefore, a new current sampling safety verification scheme is needed to achieve both hardware economy and verification instantaneity. Disclosure of Invention In view of the above, the present application aims to provide a method, an apparatus, a device and a medium for safety verification of dual current sampling of an energy storage system, which are used for detecting faults of a battery heating loop based on the heating loop current, and simultaneously judging the consistency of frequency domain harmonic energy distribution and analyzing time domain steady-state current deviation, so as to realize mutual verification of dual current sampling, improve the reliability and functional safety of the system, and not increase the number of hardware current sampling. The embodiment of the application provides a safety verification method for double-current sampling of an energy storage system, which comprises the following steps: a first current detecting part is arranged at the positive end of the battery in the battery heating loop and at a position outside the heating loop, and a second current detecting part is arranged at the negative end of the battery; Determining a heating loop current based on a first current sampling signal of the first current detection component and a second current sampling signal of the second current detection component which are acquired in real time, and performing battery heating loop state monitoring and fault diagnosis based on the heating loop current; And carrying out frequency domain harmonic energy distribution consistency judgment and time domain steady-state current deviation analysis on the first current sampling signal and the second current sampling signal to determine the abnormality of the current detection component and dynamically select the main loop current value. In one possible implementation manner, the determining the heating loop current based on the first current sampling signal of the first current detecting component and the second current sampling signal of the second current detecting component, and performing battery heating loop state monitoring and fault diagnosis based on the heating loop current includes: determining the heating loop current based on the first current sampling signal and the second current sampling signal; when a voltage exists between the anode and the cathode of the battery and the heating MOS tube is in a closed state, if the current of the heating loop is in a fault preset range, determining an open circuit fault of the heating loop; when a voltage exists between the anode and the cathode of the battery and the heating MOS tube is in a closed state, if the deviation between the resistance value of the heating resistor calculated based on ohm law an