Abstract: A method for inter-turn fault detection in a current transformer (CT). The method includes obtaining a first inter-turn fault index of the CT, obtaining a second inter-turn fault index of the CT, and detecting an inter-turn fault in the CT based on the first inter-turn fault index and the second inter-turn fault index. Obtaining the first inter-turn fault index includes coupling an AC power supply to a secondary winding of the CT, measuring an electric current passing through the AC power supply, obtaining a hysteresis curve of the CT from the electric current, and calculating the first inter-turn fault index according to the hysteresis curve. Obtaining the second inter-turn fault index includes injecting an AC current to a primary winding of the CT, measuring an open-circuit voltage waveform of the secondary winding, and calculating the second inter-turn fault index according to the open-circuit voltage waveform.

Abstract: A method for measuring a dissipation factor of a voltage divider of a capacitor voltage transformer (CVT). The CVT includes a capacitor voltage divider (CVD), an intermediate voltage transformer (IVT), and a compensating reactor (CR). The CR is connected between the CVD and the IVT. The method includes measuring a grounded specimen test (GST) mode current that passes through a first capacitor of the CVD by coupling the current sensor in series with the first capacitor, measuring an ungrounded specimen test (UST) mode current that passes through a second capacitor of the CVD by coupling the current sensor in series with the second capacitor, and obtaining a dissipation factor of the CVD based on the GST mode current and the UST mode current.