Calculation of Durability and Optimization of Winding Frame Structure of Transformers

Short circuit at ultra-phase transformers causes a very dangerous mechanical force; it can bend, move, destroy the winding and even breaks transformers. In case of short circuits, the assessment and calculation of mechanical strength under the action of electromagnetic force is essential. This paper uses the analytical and finite element methods to calculate reliability of low voltage winding of 3-phase 250KVA-35/0.4 kV in the case of short circuit at three phases. The results of two methods are compared in order to pick out a computational analysis process with minimal time and greatest reliability. Then, optimizing the winding frame structure is done to satisfy the conditions for short circuit and at the same time reduce the cost of design and manufacture