TEE (2015) 28-35 © STM Journals 2015. All Rights Reserved Page 28 Trends in Electrical Engineering ISSN: 2249-4774(online), ISSN: 2321-4260(print) Volume 5, Issue 1 www.stmjournals.com Speed Control of An Inverter Fed Three-Phase Induction Motor Using IP Controller Considering Core Loss and Stray Load Loss Ridown Rashid Riadh*, Mohammad Al-Imran, Abdullah Mohammed Shobial, Md. Shahjalal, Mohammad Abdul Mannan Department of Electrical and Electronic Engineering, American International University-Bangladesh , Road14, Block-B, Kemal Ataturk Avenue, Banani Abstract Consideration of core losses and stray load losses to design a controller of an inverter fed induction motor are affected to the flux and torque decoupling strategy adversely. As a consequence, the detuning of field-oriented control (FOC) is required. The detuning strategies have been developed in some literatures. But the implementation of detuning becomes difficult because of higher order expression. In general, the controlling and estimation of AC drives are considerably more complex than those of DC drives. This complexity increases substantially if high performances are demanded. The main reasons for this complexity are the need of variable frequency, harmonically optimum converter power supplies, the complex dynamics of AC machines, machine parameter variations, and the difficulties of processing feedback signals in the presence of harmonics. To avoid the detuning strategies and to minimize the overshoot and steady state error problems which occur while using a conventional PI controller, the decoupling control strategies with integral plus proportional controller have been proposed in this paper. Keywords: induction machine, core loss, stray loss, IP controller, inverter *Author for Correspondence E-mail: rashidridown@gmail.com INTRODUCTION An asynchronous AC motor in which the rotor receives electric power by induction is familiarized as induction motor. Of all AC motors, three-phase induction motor is the one which is extensively used for various kinds of industrial drives because of its simple and extremely rugged unbreakable construction alongside sufficiently high efficiency. It starts up from rest and needs no extra starting motor and has not to be synchronized [1]. But it has to sacrifice some efficiency to vary the speed. We are in a mission to achieve desired speed at certain condition by varying its speed without sacrificing efficiency. The desired speed is achieved by using four IP controllers namely, the speed controller, flux controller and stator d-axis and q-axis current controller, which is composed utilizing the IP controller. IP gives an overshoot free response in comparison to PI controllers which are used usually. It shows better performance regarding the clearance of steady state error which occurs in other controlling process [2]. The designed controller, which decouples torque and flux provides d-axis and q-axis stator voltage components. The gains of the controllers are chosen by setting poles in left half of s-plane with proper electing of natural frequency and damping ratio with the purpose of achieving stable operation of the proposed IP controller. The proposed speed controlling process of IM using IP controller was substantiated in simulations using Matlab/Simulink and effects have demonstrated astounding execution. Despite of taking stray load-loss and core loss into account, it was originated that the proposed IP controllers can provide excellent performance in speed [2]. The voltage and torque equations that describe the dynamic behavior of an induction motor are time-varying. The dynamic analysis of the symmetrical induction machines in the arbitrary reference frame has