LV/HV EN STANDARD TRANSFORMER BUSHING

The transformer bushing is the main insulation device outside the transformer box, and the lead wire of the transformer winding must pass through the insulating sleeve to insulate the lead wire and between the lead wire and the transformer shell, and at the same time play the role of fixing the lead wire. Due to different voltage levels, insulating sleeves are in the form of pure porcelain sleeves, oil-filled sleeves and capacitor sleeves. Pure porcelain bushing is mostly used in 10kV and below transformers, it is in the porcelain sleeve to wear a conductive copper rod, porcelain sleeve for air insulation; oil-filled sleeve is mostly used in 35kV transformer, it is in the porcelain sleeve oil-filled, in the porcelain sleeve to wear a conductive copper rod, copper rod wrapped insulating paper; capacitive bushing is used in 100kV or more high-voltage transformer, by the main insulating capacitor core, the outer insulation upper and lower porcelain parts, connecting sleeve, oil pillow, spring assembly, base, equalizing ball, measuring terminal, terminal, rubber washer, insulating oil, etc.

INTRODUCTION:

The transformer bushing is an insulating sleeve that leads the high and low voltage leads inside the transformer to the outside of the fuel tank, not only as the lead wire is insulated to the ground, but also plays the role of fixed lead, the transformer bushing is one of the transformer current-carrying components, in the operation of the transformer, the load current is passed for a long time, and the short-circuit current occurs when the transformer is short-circuited outside. Therefore, there are the following requirements for the transformer bushing: (1) It must have the specified electrical strength and sufficient mechanical strength. (2) It must have good thermal stability and be able to withstand instantaneous overheating in the event of a short circuit. (3) Small appearance, small mass, good sealing performance, strong versatility and easy maintenance.