Optimal design of single-phase shell-type distribution transformers based on a multiple design method validated by measurements

This paper presents a method for the design of shell-type, single-phase distribution transformers to obtain the manufacturing specifications. The method is simple, efficient and accurate. By an exhaustive analysis, it is concluded that the obtained solution is the global optimum. The following constraints are imposed: excitation current, no-load losses, total losses, impedance and efficiency. The methodology of this paper requires only six input data: transformer rating, low voltage, high voltage, connection of low-voltage coil, connection of high-voltage coil, and frequency. These data are included in the transformer nameplate. In this paper, the minimization of the following four objective functions is considered: total owing cost, mass, total losses and material cost. The consideration of these four objective functions is implemented automatically by running the optimization algorithm four times without intervention of a designer. Consequently, transformer manufacturers save design man-hours and increase capacity. A design example on a 25 kVA transformer is presented for illustration. The optimized solutions of transformer design are validated with laboratory and process measurements.