An approach to the AC to AC/DC converter

The paper describes an input and output insulated AC to AC voltage converter, which has nearly unity power factor and regulating function, based on the bi-directional PPM (pulse phase modulation) switching technology. The converter also has AC to /spl plusmn/ variable DC voltage conversion function, that is operating at high frequency PPM control of the bi-directional solid state switching elements, which acts as synchronized to the AC power line polarity. By implementing the new type of AC to AC converter, wide power output capacity ranging from single phase 50 watt to three phase 50 kwatt can be covered, and might be adaptable to conventional power transformers or as replacement to slide regulators. The converter can also be applicable for UPS, battery charger and polarity inverse rectifiers for the servomotor or chemical treatment facilities.