Design and Simulation of Fuzzy Logic Controller for Variable Frequency Drive of Three Phase AC Induction Motor

A.Z. Ahmad Firdaus, S.A. Azmi, Kamarulzaman Kamarudin and Nurul Izyan Norazli

Three phase AC induction motor is the workhorse in industry where they count for 85% of the type of motor used. They are mostly used as prime movers for fan, pump, and centrifuge where conventionally, operated at fixed speed. Variable speed drives have proven to give better efficiency compared to mechanical control such as using valve or damper in flow control applications. This may be attained through variable frequency drive (VFD) where stator frequency could be varied to adjust motor speed. For closed-loop control, fuzzy logic controller (FLC) can offer viable option for VFD over the more conventional PID controllers due to simplicity in design, bypassing the complex tuning process in PID while still giving good control performance. In this paper, SPWM signal is generated as inverter trigger signal using the algorithm derived from literature. A VFD system consists of three phase six pulse inverter triggered by sinusoidal pulse width modulation (SPWM) signal generation algorithm and connected to three phase AC induction motor was designed and simulated using MATLAB/SIMULINK software. Speed test was performed in open loop design in order to obtain the ranges of operable frequency and speed control. Fuzzy logic controller was employed as closed loop control to improve speed control. Dynamic speed test was carried out to compare performance of open loop and fuzzy logic-controlled system. Simulation result shows superior transient response performance by 13% of fuzzy logic controllers.

Volume 11 | 12-Special Issue

Pages: 834-842

DOI: 10.5373/JARDCS/V11SP12/20193283