Application of fuzzy control technology on a designed hydraulic DDV

The object of this study is to design a fuzzy self tuning controller for a hydraulic direct drive valve (DDV) driven by a VCM linear motor. At first, to evaluate the forces acting on the hydraulic valve and then choose the linear motor and the eddy current displacement sensor to measure the motion of the valve. Through the experiment, it is proven that the voice coil motor(VCM) can direct drive spool and achieve the command position precisely by a designed fuzzy self-tuning controller. Compare to the result with PID controller, one can see with the designed controller is better than PID controller. Through the experiment, this valve can be applied as the high-speed servo valve, the response time is quicker than the general servo valve 200 Hz.