CN-118501764-B - Distributed storage battery pack monitoring method, device and storage medium

CN118501764BCN 118501764 BCN118501764 BCN 118501764BCN-118501764-B

Abstract

A distributed storage battery monitoring method, device and storage medium comprises the steps of uploading acquired multi-frequency internal resistance, voltage and temperature to a main control unit through a daisy chain communication unit by a battery monitoring sensor group, sending real-time parameters of a battery to an LCD (liquid crystal display) display by the main control unit for straight tube display, processing and drawing the multi-frequency internal resistance by the main control unit in combination with an intelligent algorithm to obtain an internal resistance map of the battery, sending the internal resistance map to a storage battery nuclear host or a storage battery monitoring software platform by the main control unit, estimating capacity and real-time feedback temperature, storing monitoring data by the storage unit, and outputting switching value of a fault state to peripheral equipment by a switching value output unit. The invention can comprehensively grasp the real-time running state of the battery by collecting a plurality of key parameters of the battery, can realize the efficient convergence and uploading of the multi-point collected data by adopting the daisy chain communication structure, can accurately draw the internal resistance map of the battery by analyzing and processing the internal resistance data by adopting an intelligent algorithm.

Inventors

Zhong Yiguo
ZHANG WEI
WU FENGJING
Qian Leihong
LAI QINGHUAN

Assignees

杭州经纬信息技术股份有限公司武汉分公司
杭州经纬信息技术股份有限公司

Dates

Publication Date: 20260505
Application Date: 20240611

Claims (9)

1. A monitoring method of a distributed storage battery pack is characterized by comprising the following steps of: The battery pack is charged by a direct current power supply, and the backup batteries are connected in series according to different voltage levels to serve as backup power supplies of the direct current power supply; The battery monitoring sensor group is connected with the positive and negative of the backup battery in parallel through four-wire acquisition lines, and is powered by an external power supply/battery pack through an auxiliary power supply unit; The battery monitoring sensor group uploads the collected multi-frequency internal resistance, voltage and temperature to the main control unit through the daisy chain communication unit, meanwhile, the battery voltage collection unit converts the voltages at two ends of the collected battery into digital signals and uploads the digital signals to the main control unit, and the battery current collection unit converts the battery current collected through the direct-current Hall sensor into the digital signals and uploads the digital signals to the main control unit; The main control unit sends real-time parameters of the battery, including battery voltage, battery current, single battery voltage, single battery Chi Nazu and single battery temperature, to the LCD display through the display connection unit for straight tube display; The main control unit is combined with an intelligent algorithm to process and draw the multi-frequency internal resistance so as to obtain an internal resistance map of the battery; the main control unit sends the drawn internal resistance map to the storage battery core-capacitor host machine through the 485 communication unit, the storage battery core-capacitor host machine estimates capacity and feeds back temperature in real time, or the main control unit sends the drawn internal resistance map to the storage battery monitoring software platform through the Ethernet communication unit, and the storage battery monitoring software platform estimates capacity and feeds back temperature in real time; The storage unit stores monitoring data, the USB storage communication unit performs data transmission with the USB storage, the indicator lamp unit displays working states through the LED lamp, the working states comprise communication, operation and faults, and the switching value output unit outputs switching value of the fault states to the peripheral equipment; the multi-frequency internal resistance mapping comprises the following steps: Inputting delta I excitation current to a battery, converting frequency Fn, collecting fluctuation voltage delta V of the battery generated by current excitation, and calculating real internal resistance Xn of the battery according to a function f (Xn) =fn (delta V/delta I), wherein n is a frequency variable, and the range is 0.5HZ-7.5KHZ; Calculating the resistance to cause the battery excitation current delta I and the fluctuation voltage delta V to generate a phase difference theta through FFT Fourier function, and calculating the internal resistance value Yn of the imaginary part of the battery by using a function f (Yn) =tan theta x Fn (delta V/delta I), wherein n is the frequency variable range of 0.5HZ-7.5KHZ; and drawing a Nyquist spectrum according to the calculated values of the real internal resistance Xn and the imaginary internal resistance Yn of the battery under the corresponding frequency, wherein the abscissa is the real internal resistance, the ordinate is the imaginary internal resistance, and analyzing the capacity and real-time temperature feedback of the battery through the spectrum.
2. The method of distributed battery monitoring of claim 1, wherein estimating battery capacity based on multi-frequency internal resistance spectrum comparison comprises: testing and drawing an internal resistance map under the floating charge state of the battery, and marking the internal resistance map as C100; Recording the corresponding capacity of each battery when the battery pack discharges outwards, and performing internal resistance spectrum test and drawing and marking C95, C90..C10 and C05 when the battery discharges outwards to 5% capacity; Based on the current detection, voltage detection, and time detection accounting capacity, c=it (AH), the voltage range is 2.35V-1.8V; Establishing an internal resistance spectrum database marked by each battery under different capacities, comparing the internal resistance spectrum databases of the batteries by a table look-up LUT, searching a spectrum tested in real time with a nearest spectrum of the database, and feeding back the battery capacity by the database spectrum; And (3) carrying out charge and discharge nuclear capacity on the battery pack according to a preset period, automatically starting an internal resistance map test and timely updating map drawing.
3. The distributed battery pack monitoring method of claim 2, wherein the battery capacity internal temperature feedback based on the comparison of the internal resistance maps of multiple frequencies comprises: Placing the battery in an adjustable incubator for internal resistance spectrum test and drawing, calibrating once every 10 ℃, and correspondingly marking the temperature at-20 ℃,10 ℃, 0 ℃,10 ℃,20 ℃, 30 ℃, 40 ℃, 50 ℃ and 60 ℃, and customizing the marking spectrum into a table; during the running process of the battery, the battery monitoring sensor is used for collecting the surface temperature and the post temperature of the battery; Comparing the internal resistance spectrum tested in real time with the internal resistance spectrum database of the battery through a table look-up LUT, finding out the spectrum closest to the internal resistance spectrum tested in real time, and feeding back the temperature interval of the battery through the database spectrum.
4. The method of claim 1, wherein the multi-band internal resistance acquisition based on the adaptive band selection algorithm comprises: determining an initial frequency band set and threshold parameters, and building a battery state-frequency band response model through a support vector machine for training; The method comprises the steps of connecting voltage measuring ends at two ends of a battery by adopting a four-terminal measuring method, connecting current measuring ends at two ends and inside the battery, sequentially measuring the internal resistance value of the battery in an initial frequency band set by using an alternating current impedance analyzer, storing the measured internal resistance data in a database, and calculating the internal resistance change rate under each frequency band; analyzing the current battery state according to the battery state-frequency band response model, selecting the frequency band which corresponds to the battery state and is most sensitive as a priority measurement frequency band, calculating the internal resistance change rate of the priority frequency band, comparing the internal resistance change rate with a preset threshold value, if the change rate exceeds the threshold value, indicating that the battery state is obviously changed, needing to enlarge a frequency band set for finer measurement, and if the change rate is lower than the threshold value, indicating that the battery state is relatively stable, maintaining the current frequency band set, and dynamically adjusting the measurement frequency band set according to a comparison result; And integrating and analyzing the historical internal resistance data, extracting internal parameters of the battery by using an equivalent circuit model fitting algorithm, and predicting and diagnosing the capacity and SOH state of the battery by combining a battery state-frequency band response model.
5. The distributed battery pack monitoring method of claim 1 wherein voltage acquisition comprises: the positive and negative terminals of the battery are connected with voltage measuring lines, and a voltage acquisition circuit with high input impedance is adopted to monitor the voltage in real time; the voltage is acquired by adopting an internal ADC channel of the MCU or an external special voltage acquisition chip.
6. The distributed battery pack monitoring method of claim 1 wherein the temperature acquisition comprises: And attaching a temperature sensor on the surface or at a key position inside the battery, amplifying, filtering and digitizing the output of the temperature sensor by adopting a temperature acquisition circuit, judging the working state of the battery by monitoring the temperature change of the battery, and performing thermal management control.
7. The distributed battery pack monitoring method of claim 3, wherein: and an NTC surface contact temperature sensor is adopted to monitor the temperature change of the battery in real time, and an internal resistance spectrum test is automatically started when a temperature change threshold value is triggered.
8. A distributed battery pack monitoring device comprising: at least one processor, and At least one memory including computer program code, Wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to perform the method of any of claims 1-7.
9. A computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the method of any of claims 1-7.

Description

Distributed storage battery pack monitoring method, device and storage medium Technical Field The invention belongs to the technical field of storage battery monitoring, and particularly relates to a distributed storage battery pack monitoring method, a distributed storage battery pack monitoring device and a storage medium. Background With the development of storage battery technology, the existing monitoring method generally adopts single-point or small number of monitoring points, and cannot comprehensively reflect the running state of the battery pack. It is difficult to accurately capture the difference of parameters such as the internal voltage and the temperature of the battery pack, and the accuracy of the monitoring data needs to be improved. And the large-scale battery pack adopts a centralized monitoring architecture, a large number of sensors and complex wiring design are needed, the system structure is complex, the installation, debugging and maintenance difficulties are high, and the cost is high. In addition, under a centralized architecture, a large amount of monitoring data needs to be transmitted to the central control unit through a limited communication channel, and when the battery pack scale is enlarged, the data transmission efficiency is obviously reduced, and information bottlenecks are easy to occur. Most monitoring schemes only pay attention to battery parameter acquisition and state monitoring, lack of functions such as intelligent analysis and early warning, and cannot meet the requirements of intelligent management and optimization application of the battery pack. Therefore, how to design a distributed storage battery monitoring method to solve the problems in monitoring precision, system complexity, data transmission, reliability, expansibility, single function and the like is a problem to be solved in the current Xu Di eating management technology. Disclosure of Invention In view of the above-mentioned drawbacks of the prior art, the present invention provides a method for monitoring a distributed storage battery pack, the method comprising the steps of: The battery pack is charged by a direct current power supply, and the backup batteries are connected in series according to different voltage levels to serve as backup power supplies of the direct current power supply; The battery monitoring sensor group is connected with the positive and negative of the backup battery in parallel through four-wire acquisition lines, and is powered by an external power supply/battery pack through an auxiliary power supply unit; The battery monitoring sensor group uploads the collected multi-frequency internal resistance, voltage and temperature to the main control unit through the daisy chain communication unit, meanwhile, the battery voltage collection unit converts the voltages at two ends of the collected battery into digital signals and uploads the digital signals to the main control unit, and the battery current collection unit converts the battery current collected through the direct-current Hall sensor into the digital signals and uploads the digital signals to the main control unit; The main control unit sends real-time parameters of the battery, including battery voltage, battery current, single battery voltage, single battery Chi Nazu and single battery temperature, to the LCD display through the display connection unit for straight tube display; The main control unit is combined with an intelligent algorithm to process and draw the multi-frequency internal resistance so as to obtain an internal resistance map of the battery; the main control unit sends the drawn internal resistance map to the storage battery core-capacitor host machine through the 485 communication unit, the storage battery core-capacitor host machine estimates capacity and feeds back temperature in real time, or the main control unit sends the drawn internal resistance map to the storage battery monitoring software platform through the Ethernet communication unit, and the storage battery monitoring software platform estimates capacity and feeds back temperature in real time; The storage unit stores monitoring data, the USB storage communication unit performs data transmission with the USB storage, the indicator lamp unit displays working states through the LED lamp, the working states comprise communication, operation and faults, and the switching value output unit outputs switching value of the fault states to the peripheral equipment. Wherein, the drawing of the multi-frequency internal resistance map comprises: Inputting delta I excitation current to a battery, converting frequency Fn, collecting fluctuation voltage delta V of the battery generated by current excitation, and calculating real internal resistance Xn of the battery according to a function f (Xn) =fn (delta V/delta I), wherein n is a frequency variable, and the range is 0.5HZ-7.5KHZ; Calculating the resistance to cause the battery excitation curren