Simulation of HVDC control and transmission lines protection based on PSCAD/EMTDC

Abstract

HVDC control and protection system was introduced in this paper. The control generally use fixed-current controlin rectifier and fixed arc angle controlin inverter. The short circuit intransmission line is one of the most common faults in HVDC, so this paper choose HVDC bus differential protection as research object,introduce the mechanism of bus differential protection and use PSCAD software for simulation. This paper is mainly about thebus differential protection and auto-reclosing after the breaker action. In the simulation process, we encountered the following three questions: 1. How to convert current difference to logic signal; 2. How tocontrolthe action of circuit breaker with the control signal changing; 3. Why circuit breakers fail to function. And we put forward concrete solutions towards the above three questions.