영광원자력 1,2호기 DEH Controller 제어특성연구

Abstract

In the nuclear power plant, the large scale of turbine is inevitable because of its characteristics using the saturated steam at the secondary side. The facility which surely controls the speed and the load of this large turbine and stops it safely in case of emergency is the DEH(Digital Electro-Hydraulic) control system. DEH control system controls TV(Throttle Valve), GV (Governor Valve), IV(Intercept Valve) and RV (Reheat Stop Valve) with the Digital Computer. That is, it controls the amount of steam supplied to the turbine and thus the rotational number of turbine and the output of the generator. In Yonggwang Nuclear Power Unit 1 and 2, the computer named W2500 supplied by Westinghouse was used in MOD Ⅱ Model the DEH controller, which was replaced in 2002 by MOD Ⅲ Model using the ovation system, a distribution controlling facility of Westinghouse. With this replacement by a new system, it became necessary to study the possible problems during the operation with the reduced speed after raising the turbine speed. When this study is applied to the real plant, we can expect that it will contribute to the more reliable operation of the nuclear power plant.