A Method to Decrease Input Current Harmonics of Three-Phase Diode Rectifier by Pulse-Doubler Scheme

The three-phase diode rectifier offers several advantages such as compact, cheap, high efficiency, no EMI noise, taught for over current while the rectifier has some disadvantages such as less of output voltage controllability and large harmonics in the input current. Since there are several applications where output voltage control is not necessary, how to decrease the input current harmonics is essential to utilize the advantageous diode rectifier. Before, one of the authors had proposed a novel scheme to overcome the problem in the three-phase diode rectifier by applying pulse-doubler scheme that based on triple-frequency rectangular-voltage injection scheme. The topology, operating principle and experimental results obtained from a small size setup have been described in a published paper. In this time, a prototype rectifier of output of 12 kW is build to evaluate the performance of the pulse-doubler scheme in a practical power scale. The evaluation results are discussed in this paper