Mathematical model of operation of an induction motor with a soft-start device based on an alternating voltage regulator

Abstract

Induction motors are firmly entrenched in modern industry due to the unpretentiousness of operating conditions and relative low cost. Induction motors have a number of problems, one of which is high starting currents, which exceeds the nominal by 6-8 times and leads to false alarms of the automatic protection and to reduction of induction motor life. This problem is solved by installing soft-start devices in the electric circuit. The principle of operation of such devices is based on regulating the voltage supplied to the stator windings of the induction motor from 0 to the nominal value of the mains voltage. One of the possible ways to build voltage regulators is a transformer with a variable transformation coefficient. Soft-start devices, based on such an alternating voltage regulator, when regulating the voltage applied to the stator windings, allow to smoothly increase the stator current. This article presents the results of a study of the operation of an induction motor loaded on a nonlinear load, which is an induction motor, using a soft-start device based on variable voltage regulators. The principle of operation of soft-start devices based on voltage regulators is described, the main parameters and analytical dependencies of such devices are presented. A mathematical model of the operation of an induction motor with a soft-start device loaded on an induction motor is compiled. Electromagnetic processes in the environment of Matlab Simulink simulation are investigated. A comparative analysis of an induction motor operation with soft-start devices is carried out.