Improvement of schemes for connection of three-phase asynchronous motor to a single phase network

In the paper the review of technical devices for connection of a three-phase winding of the stator of the asynchronous motor to a single-phase network is carried out, their main advantages and shortcomings are considered. A theorem on obtaining a threephase symmetric stress system using two single-phase sources of electromotive force is presented and proved. On the basis of the proved theorem the electric scheme for connection of a three-phase stator winding of the asynchronous motor to a single-phase network is offered. In the article authors calculate currents, active and reactive power, the power factor of the two single-phase sources of electromotive force and an asynchronous motor when changing the slip in the operating range. The phase resistances of the asynchronous motor were determined using an L-shaped equivalent circuit. In the program package Matlab Simulink was carried out simulation of the induction motor connected by means of the schema under consideration. For the practical implementation of the proposed scheme as one single – phase AC voltage source can be used single-phase network, as the other – a semiconductor converter connected to a single-phase network.