Robust Performance Design of the Position System Driven by Hydraulic Servo

The log magnitude characteristic of the hydraulic servo driving position control system is tested. Then a model expression, a system expressed by which has characters very similar to the controlled plant is made out. Because there are parameters uncertainty and unmodeled dynamics as well as input disturbance in the controlled system, a lower-order robust controller is designed with the method of m-synthesis. The simulation results show that the designed controller makes the output of closed loop system can track a sine wave of 10 Hz very well, the system has a expected performance and a good restraint for the disturbance of the input.