Feasibility study of a three phase rectifier with sinusoidal net currents

This paper deals with a feasibility study for a power rectifier, which was designed as a power supply for welding equipment. Modern digital control techniques such as software generated pulse width modulation (PWM) and phase locked loop (PLL) realized in software, will be employed. With the use of an advanced single chip microcontroller (MCU) digital and analog circuit design could be reduced to a minimum. The power part is realized as a three phase bridge structure (B6) with six IGBTs with a switching frequency of 15.625 kHz. Due to the duality of the power structure, it is possible to realize both energy directions. The study contains mathematical analysis and simulation, and as a result to these studies a description of a prototype with about 15 kW