METHOD OF INSPECTION OF MAGNETIC STATE OF SUBMERSIBLE ASYNCHRONOUS MOTOR' STATOR Russian patent published in 2008 - IPC G01R31/34 H02K15/00 

FIELD: electric engineering.

SUBSTANCE: method can be used in electric engineering industry at enterprises dealing with maintenance of electric equipment used for oil production from deep wells. According to method of determination of electromagnet characteristics of magnetic circuits of electric machines' stators, magnetic circuit of stator, provided with measuring coil, is mounted onto magnetic circuit of rotor, provided with grooves and three-phase magnetizing coil. Outputs of magnetizing winding are connected to controlled three-phase sinusoidal shape industrial frequency power source through operation values' ammeters. One phase of stator's winding of submersible asynchronous motor is used as measuring coil; one package of core of rotor of submersible async motor with removed short-circuited winding is used as magnetic circuit of rotor; operation values voltage device is used as voltmeter. Voltage of power source is increased in such a way that electromotive force could be induced in measuring coil, which electromotive force is equal to Unom/n, where n is number of packages of submersible async motor's rotor and Unom is nominal voltage at phase of submersible async motor's stator's winding. Magnetic circuit of rotor is shifted in axial direction along axis of stator for distance L_st/n, where L_st is length of magnetic circuit of stator. Currents I_A,B,C are registered in phases of magnetizing coil while keeping value of electromotive force constant in measuring coil by means of controlled power source. Magnetic state of any part is inspected on base of current Ii to meet ratio of (I_A+I_B+I_C)/3. Damaged part of stator of submersible async motor can be detected in time. Magnetic properties of packages of rotor's core can be optimally brought into coincidence with magnetic properties of corresponding parts of stator during process of assembling of submersible async motor.

EFFECT: improved operational characteristics of motor; improved efficiency of operation; higher reliability of operation.

3 dwg