Design and implementation of position controller for electro hydraulic drives in turbine control system

Turbine control system uses electro hydraulic servo sub-system which is widely used in numerous automation and process industries. One of the major problems in designing an electro hydraulic system is, quantifying the dynamic behaviour of servomechanisms as per the requirements. In existing position controller main problem is non-linearity which affects the stability of the system. The basic position controller feedback from actuator generates non linear error, which is difficult to control. This paper is focused on position control of electro hydraulic servo valve for exponential input in turbine control systems. A novel design has been proposed to overcome the nonlinearity problems in electro hydraulic servo valve. Printed Circuit Board (PCB) has been developed using Computer Aided Design (CAD) STAR tool and GERBER file has been generated for PCB manufacturing. Digital position controller has been developed and implementation has been targeted on Virtex II FPGA. Analog and digital position controller has been realized in MATLAB. FPGA implementation for the developed RTL architecture has been carried out. The design speed has been improved to 80% and it utilizes 174 slices and needs 2 clock cycles per action with the maximum clock frequency of 100MHz. SI analysis has been carried out and maximum EMI emission at 24MHz is found to be 40.1351dBμV/m.