하이브리드 변압기의 2차측 위상각 변화에 따른 고조파 저감 효과 분석

Abstract

The phase shifts in the Zig-Zag windings can be used in reducing the harmonic components. To obtain the optimum hybrid transformer design, it is required to analyze the harmonic reduction rate over phase shifts in Zig-Zag windings. The photovoltaic systems are used as a harmonic source in analyzing the harmonic reduction effects of the hybrid transformer. Each phase shifts in the secondary windings of the hybrid transformer is set to 15°, 30°, 45°, 60°. From the results, it was found that the reduction rates of the hybrid transformer has maximum values when the phase shifts is 60° and has minimum values when the phase shifts is 30°. By comparing the case of 60° phase shift with the 30° phase shift, it can be seen that the reduction rates in 5th, 7th, 11th, and 13th harmonics increases by 0.84%, 1.98%, 4.12%, and 5.9% respectively. It was also found that the reduction rates increases as the order of the harmonics increases.