METHOD OF EARLY DETECTION OF INTERTURN CIRCUIT IN THE WINDING OF A WORKING ELECTRIC MACHINE Russian patent published in 2019 - IPC G01R31/06 

FIELD: monitoring and measuring equipment.

SUBSTANCE: invention relates to control and measurement equipment and can be used for establishment of occurring interturn closure in winding of operating electric machines. Summary: currents and voltages of phases of electric machine stator winding under operating voltage are continuously measured and registered. Damaged phase is determined by the difference between the parameters of its transient process (TP) and parameters of the harmonic phase of the sound phases. With the onset of the steady-state process in all phases, the graphs of the free component of the voltage and phase current are determined by subtracting voltage and phase of the graphs of the steady-state voltage and phase curves from the plot of the voltage and current of the phase, which are extrapolation of the curves in the steady-state process until the beginning of the transient process. Finding inductance of turns subjected to closure by dividing according to ordinates of corresponding time moments of free component of voltage gap of damaged phase by negative derivative of free component of PC current of this phase. Under the condition of equal and positive values of the result of division the conclusion on the originating interturn closure is made. At the same time found value corresponds to inductance of coils subjected to closing. By ratio of inductance of coils subjected to closing, to inductance of coils of undamaged phase, ratio of closed turns is determined. In case of equal values of currents and voltages of phases after completion of PP there is determined a short-term unstable occurrence of short circuit between turns. In case of inequality between values of currents and voltages after termination of TP there is formed formation of stable interturn closure in phase, having values of currents and voltages, different from other phases.

EFFECT: technical result: obtaining diagnostic indicators on detection of incipient interturn closure in winding of electrical machine, which is under operating voltage without changing mode of operation.

1 cl, 2 dwg