Parallel operation of inverter using trans-Zsource network

There is strong demand for high-power application for photovoltaic and wind power generation systems. The realisation of a high power conversion system is usually limited by the available switching devices because of the maximum voltage and current ratings, losses and switching frequency. Thus, utilising parallel-connected power converters rated at more minute power levels are highly desirable. A robust approach for such a realisation would result in many advantages, such as modularity, ease of maintenance, (n + 1) redundancy and high reliability. The parallel operation of a voltage-fed (VF) trans-Z-source inverter (ZSI) is presented. A two parallel connected VF-trans-ZSI is introduced and a similar concept is extended to N-parallel connected inverter. A 2.9 kW prototype inverter is built and tested to verify the performance of the proposed inverter.