DEVICE FOR PROTECTING SINGLE PHASE TRANSFORMER WITH VARIABLE TAB AND ITS CONTROL METHOD

摘要

The present invention relates to a single-phase variable tapped transformer protection device and a control method for protecting an electronic variable tapped transformer from external electromagnetic influences. In the present invention for realizing this, variable taps are installed at each of a plurality of positions having different winding numbers in the primary coil of the transformer, and the variable taps to adjust the transformation ratio with the secondary coil by changing the connection state of the variable taps. In the protection device of a single-phase variable tapped transformer having an electronic switching device respectively connected to the field, the primary coil is separated into a first primary coil and a second primary coil, each of the first primary coil and the second primary coil. The variable taps at the inner ends are connected in series by the first electronic switching element, and are installed stepwise in the outer end direction so that the transformation ratio gradually decreases at each variable tap at the inner ends of the first and second primary coils. The second electronic switching device to the N-th electronic switching device are connected to the variable taps, and the first electronic switching device is kept in an off state normally at both ends of the first electronic switching device, and then turned on when the first electronic switching device is turned off by an accident. It is characterized in that the connected mechanical switches are connected in parallel.