Speed control of a hydrostatic drive using inverse steady state model

In this article a state of the art system inversion based control (SIBC) technique is proposed for regaining the speed of a pedagogical hydrostatic drive to its desired speed under changed load torque on the drive shaft. The input calculation through the SIBC is activated only when steady state value of the output deviates from the desired level. Therefore, the desired output is attained without making the system closed loop. As a result, neither high frequency oscillation (chattering) in the control input nor the risk of closed loop instability comes into the picture as of PID controller where system output is continuously compared with the reference to calculate the input.