Analysis and design of indirect field orientation control for induction machine drive system

This paper presents analysis, design and simulation of the indirect field orientation control (IFOC) of an induction machine drive system. The control scheme is explained using the principle of field orientation for the control of an inverter fed induction machine. The analysis, design and simulation of the IFOC of induction machine drive system is carried out using the transfer functions that have been derived for the field oriented control (FOC) induction machine at the synchronous reference frame. The controllers to be designed and analyzed are the one degree-of-freedom controller (1DOFC) i.e. proportional plus integral (PI) and two degrees-of-freedom controllers (2DOFC) for speed and currents to reduce the effects of parameter variations and external disturbances. To verify the design of controllers and system performance, the drive system simulation is carried out using SIMULINK for MATLAB. An IFOC induction machine drive system Toolbox (IFOCIMDS) is created to contain the adequate useful blocks in simulation of this control system. The desired current and speed tracking control performances of the drive can be preserved under wide operating range and good load regulating performance can also be obtained. The dynamic performance of the drive system for different operating conditions is studied with application of 2DOFC controller in the speed loop. Taking into consideration the parameter variations of the induction machine, the dynamic performance have been studied under load changes and set-point variations. The simulation results are provided to demonstrate the effectiveness of the proposed controllers.