Modern design of 630 kVA power transformer

摘要

The transformer has a hollow lead or conductor as the CU or ALU lead for the low-voltage coil (1). An insulating cooling fluid flows through the hollow lead in a closed loop. The transformer also has a cooling radiator (2). Preferably the middle or high voltage coil (3) is embedded in a coolant medium which can be e.g. an insulating fluid, a paste, air or SF6 gas. Its heat is dispersed to the surrounding boiler wall independent from the coolant loop of the overvoltage loop. The latter may have a coolant supply with a pressure discharge membrane (7) in the upper part of the boiler (5). The membrane (7) is discharged in a space connected to the surrounding air. By dividing the circulation loop, the transformer can be made smaller with increased power. The over-voltage coil may be made of an aluminium or copper tube with high mechanical resistive torque and has high resistance to short circuiting when wound in a spiral.