Novel hybrid 12-pulse line interphase transformer boost-type rectifier with controlled output voltage

This paper describes two novel hybrid 12-pulse line interphase transformer rectifier systems with integrated single-switch or two-switch boost-type output stage. The boost stage allows controlling the output voltage to a constant value independent of line voltage or output power variations. In combination with low complexity and/or high reliability the hybrid rectifier concept therefore is of potential interest for supplying electrically powered actuators of future more-electric-aircrafts. The principle of operation and the dimensioning of the systems are discussed. Furthermore, a control concept guaranteeing a symmetric distribution of the load current to the individual systems of the two-switch topology is proposed. The theoretical considerations are experimentally confirmed for a 10 kW laboratory prototype. Finally, the single- and the two-switch system are comparatively evaluated concerning input current ripple, power factor, and overall efficiency.