Inverter topologies for DSTATCOM applications-a simulation study

This paper describes a few different topologies of inverters used for realizing a distribution static compensator (DSTATCOM). A brief introduction of the need for shunt compensation as well as the requirements of the shunt compensator has also been given. An algorithm for generating references has been described. Three major topologies of inverters - three-leg inverter with single dc capacitor, three-leg inverter with neutral clamped dc capacitors, four-leg inverter and three single-phase inverters with common dc capacitor - have been described and simulated. DSTATCOM topologies for high voltage distribution systems have also been described. The Voltage Source Converter (VSC) topologies have been compared on the basis of the performance of the inverter for certain chosen system conditions and the number of switch devices and dc capacitors used. All simulations have been performed using PSCAD/EMTDC.