ABSTRACT
It is necessary to design transformers to withstand various possible faults, such as a short to ground of one or more phases. The high currents accompanying these faults, approximately 10 to 30 times normal, produce high forces and stresses in the windings and suppon structure. Also, depending on the fault duration, significant amounts of heat may be generated inside the unit. The design must accommodate the worst case fault which can occur from both the mechanical and thermal standpoints.
