Design of interruption process for HVDC system using vacuum circuit breaker based on virtual current zero

This paper deals with the interruption scheme designed using Vacuum Circuit Breaker (VCB) based on zero crossing characteristics, implemented electromechanically for High Voltage Direct Current (HVDC) system. The operation is carried out using Mechanical scheme as it has minimum energy loss in comparison to Solid-State and Hybrid schemes. The Mechanical scheme consists of series connection of multiple modules, variable resistors, VCB, and RC snubber circuit. The commutation is performed through a commutation branch that consists of LC circuitry and a switch. An inverse current is injected in the system through commutation branch at the instant of fault occurrence to interrupt the arcing process. MATLAB is used for designing the simulation of the proposed scheme. The results of the simulation are analyzed and improvements from previous schemes are discussed.