Experimental Research of a Variable-Speed Pitch Controlled Wind Turbine Based on Electro-Hydraulic Servo System

摘要

This paper proposes the pitch-controlled electro-hydraulic servo system of a variable-speed wind turbine. The experimental control system consists of Industrial Computer, PCI2006 data acquisition card, SVA-Ⅱ servo amplifier, QDY type Electro-Hydraulic servo valve, hydraulic cylinder, GA-150 type high-precision displacement transducer and load. In this system, the computer compares the signal from the feedback displacement transducer with an input demand to determine the position error, and produces a command signal to drive the flow control servo valve. The control valve adjusts the flow of pressurized oil to move the actuator until the desired position is attained.Secondly, with the electro-hydraulic servo testing equipment, a PID control algorithm is programmed with Lab VIEW in the Industrial Computer. The real time displacement curve of actuator is displayed in the computer, Experimental results show that the PID control algorithm is obviously effective and the high-precision of position control has gotten.Loading the link mechanism, the angle of wind turbine blades is adjusted and the aerodynamic power output of wind turbine can maintain stable.