Dynamics of Three Phase Inverter Fed Induction Motor Drive By FCS And I-FCS Based Predictive Current Controllers

Abstract

Abstract In modern control system dilemma Model Predictive Control (MPC) mechanism is the widely used optimization tool. This scheme predicts the upcoming behavior of a plant parameter by defining a mathematical model in terms of present state variables. In this paper Predictive Current Control (PCC) techniques of a Three Phase Inverter fed Induction Motor (IM) Drive have been proposed. The predictive control action is categorized in to Finite Control Set (FCS) and Integral Finite Control Set (IFCS) approach. FCS-MPC control algorithm is based on evaluation of a cost function and selecting the control signal from a finite set of signals which satisfies minimum value of the cost function, which is formulated by calculating the square error, i.e. the reference current against the stator measured current. But in IFCS-MPC method cascade feedback structure is employed with appropriate controller gain to obtain an optimal set of control variables. With the direction in minimization of principle, these methods provide the control of the switching states for inversion, to the inverter and inverter generates actuating voltage signals to the induction motor. In these methods, finite numbers of vectors of voltages are considered to achieve the switching states for operation. The electromagnetic torque and load currents of IM obtained from each of the implemented control techniques have been compared to identify the most flexible and robust predictive strategy. All these control methods have been investigated using MATLAB/Simulink environment.