Implementation of multilevel vsc topologies for dstatcom

This paper compares three converter topologies for the implementation of custom power flexible ac transmission system (FACTS)controllers, (DSTATCOM): three multilevel topologies (multipoint clamped (MPC) or Diode clamped multilevel converter (DCMLC), chain or flying capacitor (FCMLI), and nested cell or H –Bridge or Cascaded multilevel). In keeping with the need to implement high-power inverters, switching frequency is restricted to line frequency. The study addresses device count, restrictions on voltage control. The proposed medium voltage distribution static compensator (DSTATCOM), with high voltage power semiconductor modules and series& shunt booster transformer, is designed to protect sensitive loads at power distribution systems. A control technique based on voltage and current vectors also proposed for custom power devices. Experimental results carried out by using computer program (MATLAB/Simulink) to validate the performance of the DSTATCOM models. Simulation results show the performance of the proposed medium voltage custom power devices and prove the validity of the proposed topologies. Conclusion drawn from simulation studies and comparison has done for the topologies for applications of custom power devices.