State-of-charge estimation of super-capacitor using dual extended Kalman filter

In this paper, dual extended Kalman filter is implemented to estimate SoC, internal resistance and capacitance of the super-capacitors applied in hybrid electric vehicles(HEVs) simultaneously based on its first-order equivalent circuit. Both simulation and experiment are carried out to verify the performance of the algorithm. Simulation results demonstrate that the algorithm reduces the estimate errors significantly made by sensor noise and experiment results prove that the estimations are able to converge to real value rapidly under poor initialization.