Abstract: A D.C.motor speed control system with a load torque compensation is presented in this paper.The equivalent load torque will be obtained by using measurable armature current and motor speed signals,and liner network acts with a control signal in the system to overcome the influence on the speed of D.C.motor to load torque.Numerical examples are provided to illustrate the considered system not only has good dynamic and static performances,but also has strong capability of objection to load torque disturbance.

Key words: D.C.motor speed control； load torque； compensation control； high performances；