부산대학교 도서관

Reliable battery model and identifi ed model parameter are the preconditions for Power battery state estimation with high precision. Aiming at the disadvantage of existing integer order impedance modeling in characterizing the dynamic characteristics of Lithium-ion ferrous phosphate (LFP) batteries, a simplifi ed fractional order (FO) impedance model including constant phase element and Warburg element is proposed based on the analysis of simplifi ed electrochemical impedance spectroscopy curve. With the Grunwald–Letnikov defi nition based factional order numerical calculation, the FO Kalman fi lter (FO-KF) method based on the derived model is designed to identify the FO impedance model parameter and terminal voltage. The proposed FO impedance model can better represent the nonlinear dynamic performances of LFP batteries, and the Grunwald–Letnikov defi nition based FO-KF algorithm can maintain good accuracy in the numerical calculation of FO parameter identifi cation. The experimental validation results show that the combination of simplifi ed FO impedance model and FO-KF method can improve the modeling precision and parameter identifi cation performance compared with the common integer order impedance model under two diff erent test conditions.