Joint estimation method for SOC, SOH and SOE of battery

Abstract

The invention discloses a joint estimation method for SOC, SOH and SOE of a battery. The joint estimation method comprises the following steps: S1) reading a state initial value and a capacity initial value of the battery; s2) establishing a second-order RC equivalent circuit model of the battery according to the characteristics of the battery; s3) acquiring data through an HPPC, and identifying the data by using a least square method to obtain model parameters; s4) according to the state initial value, the capacity initial value and the model parameters, establishing a battery SOC, SOH and SOE joint estimation multi-scale calculation formula through an EKF algorithm; and S5) calculating SOC and SOE according to the real-time voltage, the real-time current and the initial capacity calculation value, calculating SOH after reaching time T, and then synchronously updating the SOH to SOC and SOE calculation. According to the scheme, the real-time performance and accuracy of calculation can be ensured, and the calculation complexity can be reduced.

Description

technical field [0001] The invention relates to the technical field of battery management, in particular to a battery SOC, SOH, and SOE joint estimation method. Background technique [0002] With the market share of new energy vehicles increasing year by year and the scale of energy storage expanding, the market has higher and higher requirements for battery management systems. SOC (State of Charge, state of charge), SOH (State of Health, state of health), SOE (State of Energy, energy state) are the key technologies of the battery management system. Accurate SOC, SOH, and SOE estimation can effectively avoid battery overheating. Unfavorable phenomena such as charging, over-discharging, and rapid decay of cycle life. At this stage, the main SOC and SOE estimation methods are similar, such as ampere-hour integral method, Kalman filter method and neural network method; SOH estimation methods are mainly cycle capacity method, model method, Kalman filter algorithm, etc. Because...

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Problems solved by technology

[0003] The present invention mainly aims to solve the problems of low calculation accuracy and complex methods of battery SOC, SOH, and SOE in the prior art, and provides a joint estimation method for battery SOC, SOH, and SOE, which uses the EKF algorithm for joint estimation of SOC, SOH, and SOE , which not only ensures the accuracy and real-time performance of the calculation, but also reduces the computational complexity

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