An online technique for condition monitoring of capacitor in PV system

DC-DC converters are used to interconnect solar photovoltaic (PV) to a dc micro grid or to a battery. Capacitors are connected at the output of a PV terminal to minimize power pulsation. Operational life of capacitor decreases due to various electrical and environmental parameters. In this paper, a method for condition monitoring of the capacitors used in PV system is proposed. The technique combines the estimation of equivalent series resistance (ESR) and capacitance in one tool. This technique allows reliable prediction of capacitor life as compared to existing techniques. The proposed method can be implanted in the same microcontroller that is used for implementing the maximum power point tracking. To validate the efficacy of the method detailed simulation studies are performed in MATLAB-Simulink.