DC Link Capacitor 열화에 따른 태양광 인버터 입출력 특성 = PV Inverter Output Characteristics According to Deterioration of DC Link Capacitor

다국어 초록 (Multilingual Abstract)

The DC-Link capacitor, which is the input terminal of the PV inverter, plays a role in charging/discharging and smoothing the DC voltage and smoothing the ripple. These capacitors are inexpensive, and most aluminum electrolytic capacitors are used due to their relatively fast charging/discharging characteristics. However, in DC-Link capacitors, accidents occur due to electrolyte ejection and explosion due to aging and deterioration due to increased usage time. Also PV inverter manufacturers provide status information according to usage time and related circuit design is not reflected. Therefore, in this paper, a circuit capable of simulating the occurrence of capacitor deterioration was proposed in order to examine the input/output state of the PV inverter according to the capacitance change of the DC-Link stage capacitor. By diagnosing the current state of the photovoltaic inverter due to aging and deterioration due to the change in the capacity of the DC-Link capacitor, it is possible to prevent failures in the photovoltaic system and accidents due to fire in advance. In addition, by monitoring the condition of capacitors according to the progress of deterioration, the contents of the study were proposed so that the safety and reliability of new and renewable energy facilities can be secured by obtaining appropriate information such as the life expectancy of parts and replacement time for maintenance.

참고문헌 (Reference)

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5 C. H. Lee, "Equalization of renewable Energy Generation Cost Forecast : Focusing on Solar Power" 23-32, 2019

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