Parallel operation of multi-mode Voltage Source Inverter modules with equal load sharing in single phase AC systems

This paper presents a practical control method for parallel operation of voltage source inverter modules with equal load sharing of the inter-connected modules. The main focus of the paper centers on control methodology for achieving precise phase synchronization for equal load sharing with minimum current circulation between the paralleled power converter modules, robust dynamics system control under different transient conditions. A form of communication between the converter modules Is required for energy monitoring, real time control and diagnosis for scalable single and/or multi-phase systems and is introduced in the paper. Simulation and experimental results of the digital control implementation of multiple converter modules are also presented. Lastly this paper covers an introduction to multi-mode operation of voltage source converters.