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What happens if the external short circuit of the transformer?

Time: 2020-07-30 11:04    Auther: Ztelec group

When the transformer has an external short circuit, what changes will happen to the transformer? Knowing these will facilitate us to better solve the problem.

       Regarding the management status of this abnormal power supply system, analyze the external short-circuit fault of the transformer. As we all know, the common faults of transformers are divided into internal common faults and external common faults.
       When a short-circuit fault occurs suddenly outside the transformer, its high-voltage side is impacted by the short-circuit capacity. At the moment of frequent failures, the short capacity will generate strong electric driving force before the switch is closed. This electric driving force is effective for the belt resistance. The electric driving force can be divided into the radial force and the radial force in the transformer winding resistance (also called the axial force).

       In the event of a short-circuit fault, the radial force acting on the winding resistance can withstand the supporting force of the high-voltage winding; the radial force acting on the winding resistance can withstand the working pressure of the bottom pressure line. Because the winding resistance of the transformer is ring-shaped, the ring-shaped block under the operating pressure is more easily deformed than the supporting force, so the bottom pressure line resistance is easily deformed. The radial force caused by the sudden short-circuit fault reduces the winding resistance, resulting in the radial deviation of the high and low voltage winding resistance. So the laser force will also act on the iron core and wire cutters.
       As mentioned above, when the transformer fails due to a sudden short circuit, the bottom voltage winding resistance is more likely to be deformed, followed by the high voltage winding resistance, the transformer core and the wire clamp.
       The deformation of winding resistance includes changes in radial and radial specifications, body deviation, winding deformation, short-circuit faults between windings and windings, etc. It is a potential hazard to the overall safety of the optimized operation of power engineering systems. Transformers will be broken immediately after deformation, but a large number of transformers are still working for a long time. The length of operation time depends on the relatively severe degree of deformation and location. The transformer operates as a "fault", which clearly has a common fault resistance (potential safety hazard).