Research Of Three-Phase Active Power Factor Correction

The input currents of the off-line utilities are greatly distorted when traditionalrectifier is employed, because of the using of nonlinear elements. The harmoniccurrent pollutes the power grid and causes interfere between electronic equipment.Two major ways to solve the problem are: a) compensate the harmonic of power grid;b) Redesign the off-line utilities. Harmonic compensation is a passive method, andrequires a set of special purposed equipment. Traditional passive filters are bulky andheavy and power factor improvement ability is limited. It is an active method thatelimination or reducing the harmonic of the utilities by itself, and is superior to theharmonic compensation. Hence, the Power-Factor-Correction (PFC) technologybecomes one of the hottest topics in field of power electronics recently. PFC adoptsactive method, which eliminate harmonic form the source, stands for the future trend.In this thesis, a One-Cycle controlled and soft-switching technology ofthree-phase single-switch DCM boost rectifier is described. At first, we reviewed thecontrolled method of high power factor techniques around the world and research ofthree-phase active power factor correction. Then, after introducing the operatingprinciple of three-phase single-switch DCM boost rectifier, the reason why theproposed circuit can reduce the input line current total-harmonic-distortion (THD),improving the power-factor and characteristics of the whole system is also given. Thefamous simulation software toolkit SIMPLORER6.0 is used to simulate the proposecircuit. Based on the simulation waveforms, an experimental installation is given.Finally, the experimental waveforms and results are given.In conclusion, the correctness and feasibility of this One-Cycle-Controlled andsoft-switching technology of three-phase singe-switch DCM boost rectifier are provedby our theoretical analyses, simulation research and experimental validation. Theinput power factor of the converter is very high.