Patent RU-2708533-C1 (RU)
Title: Method of operational control of technical state of bearings and stator winding of electric motor
Inventor: NEKRASOV ALEKSEJ IOSIFOVICH
IPC: G01M13/04
Filed: 2019-05-31
Granted: 2019-12-09
Abstract: FIELD: measuring equipment. 
     SUBSTANCE: invention relates to electrical measuring equipment and can be used in operation of electric motors for determination and monitoring of current technical state and prediction of service life of bearings and insulation of stator windings after completion of certain time from the beginning of operation of electric motors. Method involves measurements and calculations to determine the state and service life of bearings and insulation of an electric motor mounted on a working machine. Monitoring of technical condition and prediction of service life of both bearings and insulation resistance of stator winding of electric motor is performed simultaneously for one maintenance by an in-place method in operating conditions with determination of common control area of technical condition and prevention, limited by combined anticipatory tolerance. At that, monitoring of both electric motor bearings is performed at operating electric motor, and the state control and prediction of the electric motor stator winding insulation resistance resource is performed with the electric motor installed on the working machine disconnected taking into account the environment conditions and environment of the production facilities, in which the electric motor is operated, at known time of "clean" operation of electric motor bearing, known initial and limiting value of radial gap of electric motor bearing, as well as at known total time of electric motor in operating conditions, known initial and limiting values of insulation resistance of electric motor. At that, based on results of obtained measurements, after their statistical processing for given conditions of operating environmental factors and operating mode of electric motor, obtaining experimental graphic dependences of change of radial clearance of bearings and insulation resistance of stator winding of electric motor against time. At that, for the required graph of dependence by calculation, pre-stress value and range of anticipatory tolerance of radial clearance of bearing and resistance of insulation of stator winding of this electric motor are determined, the moment of the first diagnostic check and required periodicity of diagnostic checks taking into account required level of reliability, as well as these graphical dependencies determine during operation expected radial gap and resource of both bearings of electric motor, as well as insulation resistance of stator windings of controlled electric motor, characterizing wear of bearings and insulation at given moment in time. 
     EFFECT: technical result consists in possibility of determining joint zone of anticipatory tolerance for simultaneous performance of diagnostic checks of operational control of technical condition and prediction of service life of radial clearance of bearings and insulation resistance of stator windings of electric motors, specify time and frequency of diagnostic checks of controlled parameters, extend service life of electric motors, increase reliability of operational control. 
     1 cl, 2 dwg