Directing against the problems occurred in the digital electro-hyraulic(DEH) control system during operation in one low load range

such as fluctuation of reheat control valve's open degree in 50%~100%

complex fault location in servo-control of the valves

valve vibration resulted from abnormality in hydraulic sero-control system

and serious vibration of GV valve in the process of mode change-over test for the single/sequential valve of steam turbine etc.

the control logic has been optimized

making the DEH to obtain good control effectiveness.At the same time

in the process of developing DEH servo-control module

the design of typical fault points in module has to be considered

so as to easily predict the faults in modules.