Power Consumption Determination With Implications in Designing the Single-Phase Transformers Working in ac-Switching Mode

The goal of this paper is to fix a formula for the transformer duty factor (the ratio between the input volt amps and the load active power), as a function of load parameters (phase-shift angle) and firing angles. Basically, it is a statistic study, its input data being a collection of interest quantities waveforms, which are a representative range of the transformer working conditions. Least squares method is funding the mathematical algorithms developed to find approximating functions of the issues discussed in the paper. The input data (waveforms) were collected for a single-phase transformer, respecting the hysteresis loop of its magnetization curve. It was switching both leading and capacitive loads, considering several load phase-shift and firing angles. The mathematical support was MathCAD PLUS 6.0.