Performance Evaluation of IGBT and MOSFET Solid-State Soft Starter for 3-Phase Induction Motor

Abstract

Three phase induction motor draws up much higher current than its rated capacity during the starting of the induction motor while the motor instantly reaches the full speed. These results in a voltage drop in other physical systems connected to the same source and high electrical stress on the windings of the motor. In this research, the performance of two solid-state soft starters (IGBT &MOSFET) with a direct online start (DOL) for a three-phase induction motor in a close loop system are evaluated and compared. The research work lies in the use of extinction angle control and development of models for a close loop system on Matlab/Simulink for simulation purposes in order to determine the performance evaluation of the DOL and the solid state soft starters. The fuzzy logic controller is used to perform the system feedback. The following parameters were observed in the system with feedback: Starting Current, Speed, Torque, Total Harmonic Distortion, and Power Factor. The DOL starter, IGBT and MOSFET based soft starters all exhibit good power factor at initial start-up as none having less than 0.7 power factor. However, the IGBT-based soft starter offers better performance with respect to four of the five parameters observed, i.e the starting current, maximum torque, speed and total harmonic distortion while the MOSFET-based soft starter have a better power factor.