Polarity detection method for current transformer of main transformer bushing

The invention relates to a polarity detection method for a current transformer of a main transformer bushing. The method comprises the following steps: sequentially disconnecting connection between acurrent transformer and a primary side system and a secondary loop of the current transformer; providing a direct-current power supply and a direct-current voltmeter, connecting the direct-current power supply with a secondary side of the current transformer in parallel to form a first loop, and connecting the direct-current voltmeter with a primary side of the current transformer in parallel to form a second loop; controlling the direct current power supply to apply a single transient direct current quantity so as to generate a direct current on the secondary side of the current transformer;and according to the deflection direction of a pointer of the direct-current voltmeter, identifying whether the polarity of the current transformer meets the polarity reduction requirement or not. According to the invention, t