Dual-output four-leg inverter

A novel dual-output four-leg inverter topology is proposed in this paper. The proposed inverter which is able to provide two three-phase voltage sets of independent magnitudes and frequencies is operationally equivalent to two four-leg inverters working independently though with a reduced number of semiconductor switches and hence gate drive and control circuits. The structure of the new topology is developed and the carrier based PWM scheme is elaborated for its two subsequently defined different frequency and equal frequency operation modes. The proposed converter is compared with conventional topology in terms of characteristics of output waveforms, rating of devices and power loss. A prototype of the system is built and tested. The simulation and experimental results confirmed the validity of operation of the proposed topology.