- 계통연계형 인버터의 고조파 전류저감을 위한 LLCL 필터에 관한 연구
- ㆍ 저자명
- 안병웅,홍창표,김학원,조관열,임병국,An. Byoung-Woong,Hong. Chang-Pyo,Kim. Hag-Wone,Cho. Kwan-Yuhl,Lim. Byung-Kuk
- ㆍ 간행물명
- 전력전자학회 논문지
- ㆍ 권/호정보
- 2014년|19권 1호|pp.64-70 (7 pages)
- ㆍ 발행정보
- 전력전자학회
- ㆍ 파일정보
- 정기간행물| PDF텍스트
- ㆍ 주제분야
- 기타
In this paper, the new LLCL filter is proposed for grid connected three-phase PWM inverter for passive damping. LLCL filter inserts a small inductor in the branch of the capacitor of the traditional LCL filter to compose a series resonant circuit to reduce the switching-frequency component on grid current. Using LLCL filter, the switching-frequency current ripple components can be attenuated much better than the LCL filter, leading to a decrease in the total inductance. However, the resonance phenomena caused by zero impedance from the addition of LC branch in LLCL filter can be a big problem. Resonance phenomena of LLCL filter can be a source of grid system instability, so proper damping methods are required. However, it is difficult to apply a passive damping method in the conventional LLCL filter, because the damping resistor increase impedance of the LC branch. Therefore, switching frequency component of grid current can not much attenuated by low Q of LC series resonance effect. In this paper, a new LLCL filter is proposed to overcome the conventional LLCL filter with passive damping. The validity of the proposed method is proven by simulation and experimental result.