Development of a resonance-free power quality controller for middle voltage distribution system

In this paper, a resonance-free power quality controller (RFPQC) for middle voltage distribution system is described. The RFPQC system discussed in paper exhibits the following advantages: (a) The RFPQC has good filtering performance to eliminate most of the harmonic current generated by nonlinear load in characteristic frequency; (b) The RFPQC can damp parallel resonance between PF and grid impedance driving by load current; (c) The RFPQC also can damp series resonance between PF and grid impedance driving by grid voltage; (d) The harmonic current source in RFPQC has very small power rating comparing with nonlinear load. In this paper, the topology and control strategy has been analyzed in detail. The simulation and experiment result certify the RFPQC system has propose performance.