Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title A Study on the DC-Link Miniaturization and the Reduction of Output Current Distortion Rate by Reducing the Effect of 120 Hz Ripple Voltage on Photovoltaic Systems
Authors 송민근(Min-Geun Song) ; 이우철(Woo-Cheol Lee)
DOI https://doi.org/10.6113/TKPE.2021.26.5.342
Page pp.342-348
ISSN 1229-2214
Keywords Photovoltaic system; 120 Hz ripple voltage; DC-Link capacitor; Current distortion
Abstract The PV module of solar power systems requires maximum power point tracking (MPPT) technique because the power-voltage and current-voltage characteristics vary depending on the surrounding environment. In addition, the 120 Hz ripple voltage on the DC-Link is caused by the imbalance of the system voltage and current. The effect of this 120 Hz ripple voltage reduces the efficiency of the power generation system by increasing the output current distortion rate. Increasing the capacity of DC-Link can reduce the 120 Hz ripple voltage, but this method is inefficient in price and size. We propose a technique that detects 120 Hz ripple voltage and reduces the effect of ripple voltage without increasing the DC-Link capacity through a controller. The proposed technique was verified through simulations and experiments using a 1 kW single-phase solar power system. In addition, the proposed technique’s feasibility was demonstrated by reducing the distortion rate of the output current.