Determination of transformer capacities in an industrial factory with intermittent loads

The installed transformer capacity can be reduced when the transformer connects intermittent loads with low duty cycles. This paper proposes a new method based on genetic algorithms to determine the transformer capacities for intermittent loads. The costs of transformers are minimized while the voltage fluctuations (drops) satisfy relevant standards. The duration of the voltage drop can be derived from the Markov Process. The intermittent loads are modeled with discrete stochastic distribution; therefore, the generating function is used for aggregating multi-intermittent loads at a bus. Two practical factories with grinders and welders are used to show the applicability of the proposed method.