Dynamic Design of Electro-hydraulic Control Valve Based on Physical Simulation Model

Whether an electro-hydraulic control valve for the mixed-gas pressure control in a combined cycle power plant (CCPP) of a steel mill meets the challenge of the gas turbine depends on its dynamic response. To obtain the dynamic characteristics of the electro-hydraulic control valve before it is manufactured, a dynamic design approach based on the physical simulation model is presented. The electro-hydraulic actuator of the control valve is redesigned according to the proposed design approach. The results show that the intercoupling effect of the flow fluctuations and the pressure pulsations can result in the velocity oscillation of the electro-hydraulic actuator. By using a proper accumulator whose frequency of absorbing the pressure pulsations is equal to the flow-fluctuation frequency, the intercoupling effect is weakened, and the velocity oscillation of the electro-hydraulic actuator decreases obviously. The results are of significance for the optimization design of the electro-hydraulic control valve.