Capacitance Online Estimation Based on Adaptive Model Observer

Abstract

As a basic component in electrical and electronic devices, capacitors are very popular in electrical circuits. Conventional capacitors such as electrotype capacitors are easy to degradation, aging and fatigue due to long‐time running and outer damages such as mechanical and electrical stresses. In this paper, a novel online capacitance measurement/estimation approach is proposed. Firstly, an Adaptive Model Observer (AMO) is designed based on the capacitor's circuit equations. Secondly, the AMO’s stability and convergence are analysed and discussed. Finally, Capacitors with different capacitance and different initial voltages in a buck converter topology are tested and validated. Simulation results demonstrate the effectiveness and superiority of our proposed approach.