A Capacitance Estimation of Film Capacitors in an LCL-Filter of Grid-Connected PWM Converters

作者：Heo Hong Jun; Im Won Sang; Kim Jang Sik; Kim Jang Mok

来源：Journal of Power Electronics, 2013, 13(1): 94-103.

DOI：10.6113/JPE.2013.13.1.94

• Deterioration of film capacitor
• Grid connected PWM converter
• Injection of resonant frequency
• LCL filter

A capacitor deterioration of LCL-filter grid-connected PWM converters is progressed by the self-healing mechanism. It leads to the degradation of the filter performance and drop of power factor. Thus, it is required to diagnose fault-point of capacitors and determine the replacement time. Typically, the fault of capacitors is determined when the capacitance is reduced up to 80% from initial value. This paper proposes algorithm to the determine capacitor replacement time of an LCL filter. The algorithm takes the advantage of change of the response on the injected resonant frequency corresponding to 80% value from the initial capacitance. The results of the algorithm are demonstrated through simulations and experiments.

• 出版日期2013-1