An Online Parameter Identification Method for Non-Solid Aluminum Electrolytic Capacitors

Abstract

Aluminum electrolytic capacitors are the most commonly used components in circuit systems but are the weakest part of the systems. To make better use of this kind of components, it is crucial to monitor their status and parameter variations more accurately. This brief puts forward a prototype to test the frequency-dependent characteristics of the capacitors, both the capacitor voltage and current are acquired by using the prototype, while a variable forgetting factor recursive least square (VFF-RLS) method based scheme is applied to identify the capacitance (C) and the equivalent series resistance (ESR). Experiments are present by using the proposed scheme and the results of which are compared with the LCR meter measurement results. The extensive comparison results show that the relative error between experimental results and measurements are less than 5.03% which are acceptable compared with some other existing schemes and indicate that the proposed scheme is effective for the online parameter identification of Aluminum electrolytic capacitors.