Research Of Three Phase Power Factor Correction Circuit

With wide application of power Electronics equipment, the harmonic of power system is becoming a serious problem. These equipments mostly use the conventional rectifiers, which are non-line and consist of uncontrollable diodes, so cause the input current distorted, contains lots of high frequency harmonic.As an effective way eliminated high frequency harmonic, active power factor correction technology is researched and applied deeply. Because the middle and large power equipments account for heavy proportion and three-phase PFC has important function to solve the pollution to the unity, three-phase PFC has become hot study subject in international power electronics educational circles already.In this paper, many kinds of three-phase PFC and different control way are discussed, then modeled and simulated by Matlab/Simulink software. Theory of power factor correction and working process of different topology are researched. The disadvantage and advantage of different topology and applicable occasion are also analyzed. The study results can offer and guide the choice and optimization of various kinds of circuit topologies. Three phase single switch PFC circuit is elected from many kinds of three-phase PFC topologies, and researched in detail. According to the simulated results, the content of the 5^th harmonic is very high in the input current. The paper uses harmonic-injection method to eliminate the 5^th harmonic. The reason why the proposed circuit can reduce the input line current total-harmonic-distortion (THD), improving the power-factor and characteristics of the whole system is also given. The simulated results show consistency of simulation and theoretical analysis. Finally, an experimental equipment is designed, and some testing results are showed.