Research On One Circuit Of Three-Phase Power Factor Correction Based On One-cycle-control

AC/DC converter is the most widely used converter in the power system. But the traditional AC/DC converter's power factor is low and it's current harmonic is large, that may be harmful to the converter itself and the surroundings. So it's very significant for the research on the PFC technical. Due to the prodigious proportion of medium and big electronics equipment in power line, the research of high power factor three phase rectifier is becoming the research hotpot on international and native.In this paper, significances of Power Factor Correction (PFC) are clarified. The topologies and control schemes of three-phase power factor correction (PFC) are summarized and their traits are pointed out. And a new nonlinear control technique is proposed, named one-cycle-control.Based on the one-cycle-control concept, a three-phase three-switch PFC circuit is proposed in this thesis. Principles technique of the PFC convert is clarified. And the key formulas of the control strategy are calculated. The control technique is applied to control the duty ratio of the switch in real time such that each cycle the averaged of the switch in value of the chopped waveform at the switch rectifiers output is exactly equal to the control reference, unity fundamental power factor and low current distortion can be achieved. The proposed controller does not require multipliers and just consists of one integrator with reset along with logic IC and linear components. It simplifies the structure and complication of circuits and is easy to realize.In conclusion, the correctness and feasibility of this three-phase three-switch power factor correction converter are proved by the theoretical analyses, simulation research and experimental validation.