A Novel Technique for operating 3-phase induction motors on a single-phase mains supply with no inrush currents

摘要

A low cost method for starting conventional cage induction motors with no inrush current is described. It is applicable for both single and three phase machines to achieve starting torques several times the rated value with low stator and rotor losses. The paper describes the technique and presents computer simulations and measured experimental results of a 3-phase motor under difficult starting conditions. A protection feature, which prevents the motor from burning-out due to loss of 'synchronism' or 'stalling' at starting, is also described. The method is particularly suited to rural applications with weak power supplies where it will improve the power quality for other users on the network.