Implementation and Analysis of Microcontroller Based Soft Starters for Three Phase Induction Motors

This paper introduces two different microcontroller based three phase induction motor starters, the first using electromechanical star-delta with reactor starting and the second utilizes electronic AC voltage controllers starting technique. For each of the proposed methods, the experimental setup is implemented and the output voltage, current and speed waveforms were demonstrated and analyzed for different selection options and operating conditions. A dynamic model of three phase induction motor has been developed to validate a model of six terminals connection motor for star and delta performance analysis. The model has been utilized for the simulation analysis and comparison of various electromechanical and electronic induction motor starters techniques. Comparison between commercial analog controller based soft starter LH4-N2 and the proposed starter has been introduced as well. Experimental and simulation waveforms obtained are matched validating the proposed starters for practical applications.