A method of reducing harmonic components in a large-scale inverter

The low harmonic component elimination method, a method of PWM control, is effective for miniaturizing filters, or for decreasing losses by lowering the switching frequency. However, this method is only applicable to specific uses such as static var generators, because it can only read a switching angle decided beforehand from memory and can only control the fundamental wave. In this paper a PWM method to control low harmonic components is proposed. The proposed method uses a curved triangular wave that was developed in this investigation as the carrier wave. The proposed method proves to decrease the total harmonic distortion better than the conventional low harmonic component elimination method and the subharmonic method, based on experimental results employing a single-phase inverter. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(4): 10–23, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21103