The direct-online starting of induction motors producestroublesome torque and current transients. Soft-starting techniques,which are commonly used with three-phase induction motors, lead to morereliable operation and allow the reduction of the motor sizing: theylimit the phase currents during the starting transient in order toobtain a smooth connection to the power supply. Unfortunately, littleinvestigation has been made so far on the application of thesetechniques to single-phase motors, even if they are widely used, e.g. inhouseholds, and of course suffer of the same troubles as three-phasemotors. The present work deals with different soft-starting techniques,implemented on a simulation tool. Some of them are based on theso-called point-on-wave switching, which is in fact a delayed insertion,either simultaneous or independent, of both the main and auxiliaryphases to the main supply. In order to limit the total transient currentwithin the allowed maximum for household appliances, the gradualinsertion of the motor's main phase, is also investigated and discussed
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