Macro elements in the finite element method-application to the high-voltage insulating system design

This paper describes the use of the macro elements in the Finite Element Method. Macro elements correspond to the parts of the region and are formed using the triangular isoparametric finite elements (up to fourth order). Some internal nodes are eliminated by the so-called condensation process. Many times, the configuration being analyzed has a part of region which is being repeated (i.e., insulator chains are composed of units of the same shape, etc.). In those cases, the use of macro elements can greatly reduce the total number of unknowns, the amount of input data and the computation time. The complex potential distribution caused by resistive films on the insulator surface is calculated by decoupling the problem in two parts.