PROCEDURE DIAGNOSING FRAME INSULATION OF ELECTRIC MACHINE Russian patent published in 2004 - IPC

FIELD: electrical engineering. SUBSTANCE: procedure is intended for evaluation of technical condition of insulation of large-sized electric machines. Constant voltage U_p. is supplied to measurement object. When charging current reaches steady value object is shorted. After discharge of geometrical capacitance of object value of restored voltage U_Bm is measured at moment of its maximum. Then value of absorption factor k_a is found by formula and compared with statistic average value k_a, characteristic of given type of insulation at initial condition. Value of fall of measured value k_a with reference to initial value k_a is utilized to make judgment on technical condition of insulation. Procedure makes it possible to evaluate technical condition of electric insulation both in process of operation of electric machine and of scale models of electric insulation in process of accelerated service life tests. EFFECT: widened application field for procedure. 3 dwg