H∞ Observer-Based Battery Fault Estimation for HEV Application

This paper presents an observer-based fault estimation method for the Li-ion battery used for hybrid electric vehicles (HEVs) propulsions, where battery ageing is treated as a fault. First, the nominal equivalent electric circuit (EEC) battery model and the extended one combining the effects of temperature and fault variations are given. Then the principle of fault estimation is stated, the fault observer with the general H ∞ configuration is depicted, some weighting functions for performance description are given. Finally, the fault observer is derived and simulation results both in frequency domain and time domain are given. The simulation results illustrate the availability of the proposed observer which owns excellent robustness performance with respect to disturbances, e.g., electrical current and temperature variations.