Degradation model and maintenance strategy of the electrolytic capacitors for electronics applications

The objective of this paper is to propose a maintenance strategy for aluminum electrolytic capacitors based on the degradation model. According to the physical structure, this paper gives the equivalent circuit model and studies the main degradation mechanism. The degradation parameter is discussed in detail in the equivalent circuit model, and the failure criterion is determined about the ESR and capacitance value. Meanwhile, the power factor correction circuit is designed as a target, and the degradation parameters of its output capacitor are monitored at different temperature. The Kalman filter algorithm and direct method are utilized to calculate the parameters of ESR and capacitance. After that, the prediction model related to ESR and capacitance is established by means of the obtained degradation data respectively. The maintenance strategy is described based on the prediction model in order to achieve the lowest running cost. The proposed method can improve the reliability and stability of power electronic circuit greatly.