X-Type Current Source Converters

In this article, a novel topology generalization of a current source converter (CSC) that allows controlling of multiple single-phase ac converters independently sharing the same dc-bus, with the advantage of having a reduced number of conducting switches and a lower dc-bus current, is presented. A conventional n-output/port single-phase CSC that uses the same dc-bus needs to have n H-bridge converters connected in series, which means that it always has 2n conducting switches. The new topology allows generating any n ac output currents always having only (n + 1) conducting switches in a switching period. This represents (1 - 1/n). 50% less conduction losses when compared with the equivalent conventional multiport single-phase CSC. A scalar pulsewidth modulation to control the converters with switching optimization and its generalization is also presented. Details of topology, control strategy, and modulation are presented. Simulation and experimental results are provided to validate the theoretical approach.

Automated summary

This article presents a novel topology generalization of a current source converter (CSC) that allows controlling multiple single-phase ac converters independently while sharing the same dc-bus, resulting in a reduced number of conducting switches and lower dc-bus current. The new topology ensures generating any number of ac output currents with only (n + 1) conducting switches in a switching period, leading to a 50% reduction in conduction losses compared to conventional multiport single-phase CSCs. Additionally, a scalar pulsewidth modulation for control with switching optimization and its generalization are discussed, along with details of the topology, control strategy, and modulation. Simulation and experimental results validate the theoretical approach.