Soft Starting of High Power Three Phase Induction Motor: Theory and Applications

Abstract

In most heavy-industry, three-phase asynchronous motors have become an inevitable piece of equipment that transforms electrical into
mechanical power due to their simple and reliable structure. One major problem with the high-power motor is starting, since direct-on-line
starting of high-power motors usually cause voltage sag and over-current which may affect other equipments in the same network. Besides,
most heavy machines are sensitive to high acceleration and jerking of mechanical parts. So, having a thorough understanding of soft starting
solutions for high-power three-phase asynchronous motors is extremely important to electrical engineers. In this research, the most being-used
soft-starting solutions of three-phase induction motors are reviewed with in-depth analysis. Based-on numerical simulations carried-out with
the two most popular loads: pump/fan and dry-friction, the reader can see the effectiveness of each soft-starting method intuitively