Coupling effect and compensation of the torque servo loading system

The mathematical model was presented for the torque servo loading system with secondary regulation. Control performance under the disturbance of hydraulic and mechanical coupling was simulated with MATLAB. Simulation reveals that, with increasing of load pressure, output torque and rotational speed may deteriorate control precision. Load pressure fluctuation causes more influence on torque control system than on speed control system, while torque fluctuation causes more influence on speed control system than speed fluctuation does on torque control system. In order to eliminate the deteriorating effects of coupling disturbances, the robust compensation is featured which, on the basis of PID control, has exploited returnto- zero factor and low-pass filter. The control system has been improved to realize decoupling of the system, to raise its robustness and, after all, to improve control property.