Treatment Methods for Multi-point Grounding of Transformer Cores

Treatment Methods for Multi-point Grounding of Transformer Cores

Here are several common methods for handling multi-point grounding faults in transformer cores:

(1) For cores with external grounding leads, a resistor can be connected in series within the core grounding circuit to limit the grounding current. This method should only be used as an emergency measure.

(2) For grounding faults caused by metallic foreign objects, the problem can usually be identified by performing a tank removal inspection (uncovering the core).

(3) For grounding faults caused by burrs on the core or the accumulation of metal powder, the following methods have proven to be quite effective:

1. Capacitor discharge impulse method;

2. AC electric arc method;

3. High-current impulse method (using an electric welding machine).