PWM 인버터의 전압제어특성과 인버터 용량을 고려한 순시전압보상기(DVR)의 출력필터 설계방법

LC Filter Design for Direct Voltage Restorers Considering Voltage Control Performance and PWM Inverter Size

The cutoff frequency of a LC output filter for Dynamic Voltage Restorers (DVR) limits the control bandwidth of a DVR system and the attenuation factor against the inverter switching ripples. For a selected cutoff frequency of a LC output filter, infinite number of L-C combinations is possible. Although different L-C combination has different filter characteristics, the filter design on L-C combination has been depended on field experiences without clear analysis. This paper proposes a design criterion and design examples for the L-C filter combination considering the control characteristics and the size of DVRs. An experimental DVR system based on the proposed LC output filter design methodology is built and tested.