High quality input current waveform on soft-switching DCM boost converter applying pulse-space-modulation

To reduce the switching-loss and the switching-noise, a single-phase soft-switching discontinuous-conduction-mode (SSDCM) boost-type AC-to-DC power converter utilizing the lossless-snubber has proposed. The SSDCM power converter performs zero-voltage-switching and zero-current-switching with a simple topology and control scheme. However, the SSDM boost power converter has significant input-current harmonic distortion in the higher output-voltage range. In this paper, the authors propose a novel improvement method of the input-current waveform of the SSDCM boost power converter by applying pulse-space-modulation. In the proposed controller, the space or time-integral-value of the inductor- or input-current in each modulation period is controlled, directly. Therefore, the SSDCM boost power converter realizes high quality input-current with a simple analogue controller. To confirm the validity of the control scheme, experimental results are shown