SOC estimation method based on static polarization and Kalman filtering

Abstract

The invention discloses an SOC estimation method based on static polarization and Kalman filtering, and relates to the technical field of batteries. According to the method, SOC estimation is carriedout by utilizing an equivalent circuit model after full polarization of a cell and the Kalman filtering, and meanwhile, the equivalent total internal resistance of the cell is continuously updated; and by the method, on the premise of ensuring the electric quantity estimation precision, the number of parameters of an RC model is reduced and self-updating of the parameters is also realized.

Description

technical field [0001] The invention relates to the field of battery technology, in particular to an SOC estimation method based on static polarization and Kalman filtering. Background technique [0002] In recent years, pure electric vehicles and hybrid vehicles with batteries as the main power source have been widely used. This new type of transportation has attracted people's attention due to its low-carbon emission, energy-saving and light-weight features. However, the development of electric vehicles at this stage is largely limited by factors such as the stability, safety and service life of power batteries. The battery state of charge (SOC) is the ratio of the battery's available energy to the total energy. It is an important parameter that cannot be directly measured. The battery's state of charge is at the core of battery applications. Current values, voltages and temperatures are directly measured by sensors and therefore can only be estimated. [0003] At presen...

AI Technical Summary

Problems solved by technology

However, as m continues to increase, the number of model polarization parameters increases, and the computational complexity also increases. Therefore, in practical applications, m is usually set to be less than or equal to 3, and the calculation accuracy is difficult to guarantee.

Moreover, in actual situations, as the battery ages, the polarization of the battery will also change, which requires constant adjustment of the polarization parameters in the above estimation model, and the estimation method is too complicated

Images