FF control of CSI fed AC drives by WAN

In this paper a new control strategy for induction motor drives fed by CSI (Current Source Inverter) is proposed. A multivariable state feedback as well as FF (feed forward) control is applied for fast regulation and stability of the drive system. The design of the state feedback controller is based on the application of the pole assignment technique of industrial regulation theory to a dq axis state space linearised model of the drive and includes a reduced order observer to obtain faster dynamic response. The observer is designed to reconstruct the inaccessible states such as dq axis rotor currents from the knowledge of the system inputs and outputs. The hardware and software implementation of the controller around an inexpensive 8051 based microcontroller kit, controlled by WAN/wLAN is discussed. The simulation results for step changes in references and load torque show the possible improvement in response with the addition of feed forward control.