Comparative Analysis of FCL and Dynamic Voltage Restorer for Fault Current Limitation

Abstract

In this project Comparative analysis of FCL and dynamic voltage restorer for fault current limitation is presented. Potential fault current levels in power grids is approaching, and may eventually exceed, the short-circuit current limits of existing protection devices. Alternative to expensive system upgrades of protection devices, Fault Current Limiters (FCL’s) provide more cost-effective solutions to prevent old protection devices and other equipment on the system from being damaged by excessive fault currents. Short circuit fault is detected by sensing the load current and its rate of change. The voltage fluctuation is detected by measured change in voltage. In order to protect the grid from blackout and the sensitive equipment from damages, FCLDVR serves in efficient way. The life and quality of the equipment is improved. Combined operation of FCL-DVR is performed by a bidirectional thyristor switches in the output terminal. Switches are activated under fault condition and deactivated under normal condition. The model of a three phase grid system with different fault condition is simulated using MATLAB SIMULINK software. A new multilevel cascaded-type dynamic voltage restorer (MCDVR) is introduced to reduce the ratio of the transformer. The MCDVR provides similar cascade inverter performance benefits, such as the lower power rating and cost of the power devices used. The FCL and DVR comparative analysis is simulated by using MATLAB / SIMULINK software.