Transformation Of Speed Control System On Turbine And Study On Problems Correlated With It

Early speed control systems on turbine all adopted pure mechanical hydraulic speed control systems, which had intrinsic defects. For example, the percentage of delay is large, dynamic regulation characteristic is bad, control accuracy is low, the operation is cockamamie, the running and maintenance are not convenient, and so forth. In order to solve these problems, it is necessary to substitute a completely new, advanced speed control system for previous mechanical hydraulic one.200MW units made in China all adopt mechanical hydraulic speed control systems. 200MW units has been playing main role from 1970s, 1980s when they were put into effect in power industry. According to the motional industrial policy, they will play main role in the future. In order to adapt to the desire of modern great network and satisfy with all kinds of needs of network running, the speed control systems on turbines of 200MW units must be .transferred.With the development in electric industry and the progress of science and technique, DEH imports technique of westinghouse, which has succeeded, DEH has been adopted extensively on 300MW units. We have gained ripe experiences on design, moving, maintenance and usage, which are being perfected. It is possible to substitute DEH for hydraulic control systems on 200MW units, and technical problems don't exist. We only transplant DEH on 300MW units ingeniously to control system on 200MW units and make reasonable transformation. In the situation not influencing with normal production in power factories, we can make feasible transformation schemes, and make use of overhaul time, partly transfer previous hydraulic speed control systems, it is possible to realize AGC control.This paper discussed the feasibility and reliability of transformation on DEH control system, and compares on all kinds of transformation schemes. In addition, this paper enumerates some successful examples of transformation on DEH control systems, which makes out that the units after being transferred are reliable, AGC control has realized, and the ability of peak regulation has increased.