Three-phase single-stage high-voltage DC converter

Two techniques for generating-high DC voltage using a three-phase power supply are presented. The laboratory model of the converters is developed and tested. The converter system is based on a single-stage power conversion using an isolated flyback converter topology and cascaded voltage doubler circuit. The power switching devices in the controlled bridge are controlled by the three-phase pulse width modulation (PWM) switching technique. Low harmonic current distortion in the AC side is considered in this design. A field programmable gate array (FPGA) is used to generate the three-phase PWM pattern which makes the overall circuit compact and less discrete components are involved. Furthermore, the control bridge consists of three power switching devices with twelve diodes, and is thus less complicated to control. The performance of the converters are compared in terms of efficiency, voltage stress across the devices and voltage gain.