FIELD: electricity.
SUBSTANCE: electrical machine is in the first state of the machine, the first reference value is determined for measured values of electrical quantity. Detection of ground short-circuit includes continuous measurement of electrical quantity in the winding and detection of ground short-circuit based on the measured values of electrical quantity and the first reference value. The method includes receipt of signal (101, 102), detection of the machine state changing based on the received signal (120) and changing to the second reference value for electrical machine when change in the machine state is detected, at that the second reference value differs from the first reference value (100).
EFFECT: improved accuracy of ground short circuit detection when working state of the machine changes.
9 cl, 3 dwg
