Virtual model of an induction motor with rotor eccentricity

Abstract

A squirrel-cage induction motor is the most common motor used to drive working machines in various technological processes, including in the agricultural sector. A sufficiently large resource is laid in them by the manufacturer, but in practice the engine serves much less, due to various factors, including imperfection of diagnostic systems. Failure analysis showed that one of the common causes of failure is increased bearing wear. An increase in the rotor eccentricity is the main diagnostic parameter of this malfunction, for the detection of which a diagnostic method was developed that allows using the indirect indicator, the rotor speed, to evaluate the technical condition of the engine bearings. To identify the dependence of diagnostic parameters on the technical condition, a virtual model of an asynchronous motor with rotor eccentricity was built. The model is implemented using a package of applied mathematical programs and allows you to simulate the operation of an induction motor in various modes, such as starting, idling, steady state with the ability to change the nature of the load. As a result, we obtained the dependences of the angular velocity of rotation of the rotor, stator current, and torque on the shaft versus time for various technical conditions of the engine.