Adaptive h-infinity filter soc estimation method based on measured value residual sequence

Abstract

The invention relates to an adaptive H infinite filter SOC estimation method based on the measurement value residual sequence, aiming at the SOC (State of Charge) caused by the battery rate capacity effect and the severe change of the model parameters under the high-rate charge-discharge condition of the power battery To solve the problem of reduced estimation accuracy, an adaptive H infinite filter robust SOC estimation method based on the measurement value residual sequence is proposed: H infinite filter is suitable for strong nonlinear systems such as power batteries because it does not make any assumptions about the statistical characteristics of noise; In view of the change of the working environment and the unknown characteristics of the interference information during the charging and discharging process of the battery, the covariance matching method based on the measurement value residual sequence is used to update the state noise variance and the measurement noise variance in real time, thereby improving the robustness of the estimation method. The experimental results show that the adaptive H infinite filtering method based on the measurement value residual sequence can effectively improve the SOC estimation accuracy of the power battery under the condition of large rate charging and discharging.

Description

technical field [0001] The invention belongs to the technical field of power battery SOC estimation, and relates to an adaptive H infinite filter SOC estimation method based on a measurement value residual sequence, which is a method based on the utilization measurement value residual sequence under high-rate charging and discharging conditions. The covariance matching method combined with the H infinite filter robust SOC estimation method for power batteries. Background technique [0002] Lithium-ion power batteries have the advantages of high voltage platform, high specific energy, high specific power and long cycle life, so they are widely used in many fields. As a measure of the remaining capacity of the power battery, SOC (State of Charge) is an important indicator of battery performance. Accurate estimation of SOC can avoid overcharging and overdischarging of the battery, and ensure the safe and efficient use of the battery. The estimation method based on the equival...

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Problems solved by technology

[0004] The power battery will have the following two special problems under high-rate charge-discharge conditions: 1) Under high-rate discharge conditions, the battery will have a rate capacity effect, that is, the larger the discharge current, the less the capacity that the battery can discharge, which will lead to There is a deviation in the maximum available capacity of the battery; 2) Under the condition of high-rate charging and discharging, the polarization parameters of the equivalent circuit model change drastically, resulting in a decrease in the accuracy of battery modeling

These two issues have brought great challenges to the accurate estimation of power battery SOC under high-rate charging and discharging conditions.

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