A Nine-Switch AC/AC Current Source Converter

Current source converters (CSCs) have superior features such as no dv/dt, reliable short circuit protection, etc., and are preferable for high-power applications. A nine-switch ac/ac CSC is proposed in this paper. In contrast to traditional back-to-back (BTB) configuration, the number of switching devices in the proposed converter decreases from 12 to 9, achieving a simpler structure and lower cost. Modulation and control schemes are proposed for the nine-switch CSC to ensure the realization of dc-link current control, power factor (PF) control, adjustable output current amplitude, etc. Simulated verification is provided.