A novel class of multipulse converters based on high-frequency-operated transformers

This paper presents a novel class of multipulse converter based on high-frequency-operated multipulse transformers. Utility line currents are 12-pulse in nature with the cancellation of 5th and 7th harmonic components. The method demonstrates a considerable reduction in size and weight of the multipulse transformer, due to higher frequency operation. Furthermore, the magnetic components on the rectifier dc sides are also exposed to higher frequency and can be reduced in size and weight. The absence of bidirectional switches is also achieved by employing a modified modulation strategy. The proposed converter is suitable for medium-voltage rectifier systems, which demand clean input current. And the proposed converter employs modularity in design, which offers several benefits, such as reduction in cost and flexibility in design. This paper presents construction design, analysis, simulation and experiment results for a 3300 V, 20 kVA prototype system.