High-Gain Observer Design for Online Identification of Supercapacitor Model Parameters

Abstract

The objective of this paper is to tackle the problem of online state estimation for supercapacitors by using a strong high-gain observer. To monitor and control in real-time systems in the renewable energy domain, such as energy storage systems and electric vehicles, it is essential to accurately estimate supercapacitor parameters. Traditional estimation methods can be computationally expensive or sensitive to measurement noise. Presently, we propose a high-gain observer designed under the assumption that the supercapacitor parameters (series resistance R_s and capacitance C) are known and constant. Assuming system observability, the observer ensures asymptotic convergence of state estimates. The simulation results demonstrate fast convergence, less than 500 seconds of simulation, and robustness to measurement noise (Maximum relative error of 1%), confirming the suitability of the proposed approach for real-time implementation.