Simple Design Method of Two-Degree-of-Freedom PID Position Controller Specifying Disturbance Response for Linear Servo Motors

The aim of this paper is to develop an improved pole-zero-assignment design method suitable for two-degree-of-freedom (TDOF) PID controller for linear servo motors (LSMs). The proposed design method can uniquely determine the crossing angular frequency of sensitivity function and complementary sensitivity function from a simple algebraic expression using the maximum value of the disturbance response to a disturbance step input. This leads to removing a troublesome trial and error design process employed in the past method, and improving it into a more systematic design method. Simulation and experimental results on a vector-controlled LSM validate the proposed method.