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The standards of power correction and reducing high harmonics in power converter system was recently published in the U.S. and Europe. And regulations of the Total Harmonics Distortion(THD) on industry and electronic machines are increasing. Therefore, the studies of reducing input power harmonics and power factor correction in the power converter system have been conducted actively in order to solve these problems. With regard to this, the third phase, AC/DC Converter of PWM Type, has been researched in the world. However, PWM Control type has fundamental problems such as a lot of power loss which is occurred when it controls the main circuit and difficulty in making it as a high power converter. Therefore, it is needed to draft the plan on low pass filter or active filter as their needs. This paper proposed multi-level PWM Control converter which controls input current by combining buck converters together to improve input current characteristic, and confirmed its validity throughout simulation and experiment. This method, which is multiplying and duplicating output of converter of equal capacity, is able to control unit power factor of input current, reduce the problem caused by high frequency switching, and apply to high power converter because filter is not necessary.
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