Data Collection And Analysis Of Key Performance Of Battery Pack

In modern society,electrical energy is one of the most commonly used energy sources.As a device for storing electrical energy,battery packs have been widely used in various fields and become an important guarantee for people's normal production and life.When the power system fails,a battery pack with good energy storage can release electrical energy in time to power important equipment that needs uninterrupted power supply,so that its normal operation is not affected.The subject of this research is a battery pack consisting of 24 2V lead-acid batteries.The battery pack is monitored and evaluated by designing a battery key performance data collection device.At present,the research team has studied the key performance collection of batteries and built a distributed collection platform,but the distributed collection platform is complicated to debug and inconvenient to use.The purpose of this research is to build a centralized battery key performance collection platform,collect the basic performance parameters of single cells in the battery pack,and analyze and evaluate the battery usage status based on the collected basic performance parameters.First of all,this paper analyzes the basic structure of lead-acid batteries and the chemical reactions that occur during the charging and discharging of lead-acid batteries.It is clear that the battery voltage,temperature,internal resistance and battery capacity are the key performance parameters of lead-acid batteries.,which provided the basis and follow for the research of the paper.Secondly,this paper uses STM32 single-chip microcomputer as a microcontroller to design the acquisition circuit and realize the collection of battery voltage and temperature parameters,which meeting daily battery monitoring needs At the same time,according to the principle of the AC discharge method,the battery is controlled to discharge at a specific frequency,and the response signal during the discharge process is collected to provide signal data for the calculation of the negative impedance parameter of the single cell in the battery pack.Through the design of the gating circuit,the centralized collection function of the performance parameters of all single cells in the battery pack using the same device platform is realized.Finally,the state of charge(SOC)of the battery is estimated based on the basic performance that the device can measure.After constructing the RLC equivalent circuit model of the sample battery and simplifying it according to the actual situation of the subject,the multi-frequency point measurement method is used to measure and solve the ohmic resistance parameter,polarization capacitance parameter and polarization resistance parameter of the single cell.According to the calculated battery model parameters and the real-time voltage and current parameters of the battery,the state space inside the battery and the ohmic internal resistance of the battery are constructed respectively.Based on the Kalman filter algorithm(Kalman filter algorithm,KF algorithm)for innovative applications,it is proposed to embed the estimation of ohmic resistance in the KF estimation process of the battery SOC to form a double Kalman filter algorithm((Double Kalman filter algorithm filter algorithm(DKF).It solves the problem of real-time tracking of the time-varying parameter of ohmic resistance when estimating the state variable of battery SOC,and realizes a more accurate estimation of battery SOC performance.