Modified controller for closed loop control of CSI-fed induction motor

Steady state error due to load changes in speed response of closed-loop control of current source inverter fed induction motor (CSI-fed-IM) has been reported in many papers. Methods have been suggested by researchers to eliminate this steady state error. These methods are rather complicated. This work aims at suggesting a simpler speed controller to eliminate the steady state error of CSI-FED-IM whenever load changes occur. This simple controller makes use of a normal PI controller with the concept of reduction of disturbance by prediction. The change of load torque of the motor itself is considered as a disturbance and the linear relation between slip and torque has been utilised in the design of the controller to improve the performance