66kV burst short circuit transformer

Abstract

The invention relates to a 66kV burst short circuit transformer. A three-phase three-limb iron core is arranged in a lower fuel-saving box of the transformer. The iron core is sleeved with a low-voltage coil and a high-voltage coil. Wires are led out from the head end of the high-voltage coil and the head end and tail end of the low-voltage coil in the axial direction, and are led into a sleeve through cables. The high-voltage coil is of a fully continuous structure, wherein every two of three composite conductors are wound in parallel in the radial direction. A subsidiary pressing plate on the high voltage side and a subsidiary pressing plate on the low voltage side are respectively of a fan shape as a whole, and the fan-shaped subsidiary pressing plate on the high voltage side and the fan-shaped subsidiary pressing plate on the low voltage side share the same center of a circle and are placed in a symmetric mode. The subsidiary pressing plates and a pressing plate are provided with positioning holes and are connected through an insulating screw rod. According to the 66kV burst short circuit transformer, the insulation structures of the coils are optimized, ampere-turn balance of the coils is improved, horizontal eddy current loss of the coils is lowered on the premise that insulation reliability is guaranteed, the stress level of the coils is lowered substantially at the time of a short circuit, the capability in resistance to the short circuit of a product is enhanced, and a basis is provided for further optimization of a product design.

Description

technical field [0001] The invention relates to a transformer manufacturing technology, in particular to a 66kV sudden short-circuit transformer. Background technique [0002] With the continuous expansion of the system capacity and the capacity of a single transformer, under the condition of a certain short-circuit impedance of the transformer, the threat of short-circuit electromagnetic force to the transformer will be more serious. In order to ensure the safe and reliable operation of the transformer, it is necessary to try to improve the short-circuit resistance of the transformer winding. However, the operation practice of my country's electric power sector in recent years has shown that no matter whether it is a transformer produced by a domestic manufacturer or a transformer imported from a foreign manufacturer, under the impact of short-circuit electromagnetic force, there are still many accidents that are damaged due to insufficient short-circuit resistance of the w...

AI Technical Summary

Problems solved by technology

However, the operation practice of my country's electric power sector in recent years has shown that no matter whether it is a transformer produced by a domestic manufacturer or a transformer imported from a foreign manufacturer, under the impact of short-circuit electromagnetic force, there are still many accidents that are damaged due to insufficient short-circuit resistance of the winding. occur

Analyzing the previous transformers, in terms of structure, the axial compression of the yoke corresponding to the winding part is the most unreliable, and the wire cake at this part is often difficult to achieve the proper pre-tightening force, so the wire cake at this part is most easily deformed

And because the axial force is too large or the strength and rigidity of the end support are not enough, or the assembly is defective, the winding rises and the pressure plate is stretched apart.

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