Modeling And Simulation Research Of Steam Turbine Digital Electro-hydraulic Control System

Currently, the digital electro-hydraulic control system has been adopted in largesteam turbine in China, with its flexibility of control function and precise of regulationquality, resulting in high efficiency and high stability. Along with the DEH is becomingmore and more important in the power system, it should be continuously to research andoptimize control strategy to make it more perfect. The advanced control system requiresoperators of a solid theoretical foundation and skilled operation, and the simulationsystem will provide operators a platform to be familiar with the environment, understandthe unit performance and exercise incident handling capability. Therefore, establishing acomplete set of DEH simulation system model and doing analysis research, has greatpractical significance.This paper is based on the premise of an in-depth study on steam turbine controlsystem, using the Guodian Duyun Plant660MW supercritical unit DEH as the researchobject, and the EDPF-NT Plus simulation supporting system as the platform, using themodular modeling to build control model, establish the DEH simulation system. Thesystem includes the speed, load, main steam pressure and valve position control systemas well as the valve management system and the overspeed protection control system. Inthe repeated debugging and using, proved that the simulation system properly designedand fully functional, it has the functions of monitoring, control, security and regulation. Itis the same as the operating mode and environment of the actual unit, and used not onlyfor personnel training, but also for control strategy optimization.The digital electro-hydraulic control system has become more important in thedomestic power industry, and the DEH simulation model developed in this paper canprovide a good research platform, for those power plant operation, fault diagnosis andtreatment as well as unit performance analysis. It will promote the development andapplication of the DEH system, and the improvement of automation level of the steamturbine system.