Transformer suitability for a successful load shedding in the TSO control area

Abstract:
The increasing installation of decentralized generation units especially in the distribution grid leads to a homogenous mixture of load and generation. This demands significant adjustments to secure reliable application of emergency plans like the 5-Step load shedding plan in case of under-frequency as a result of big disturbances. This study present a method to evaluate each transformer for the best load shedding step to maximize the probability for a successful load shedding. Simultaneously the rising DG is considered with a new average value based load shedding concept. With the development of a dynamic model this investigation demonstrates the important calculation of probabilities for the suitability evaluation of each transformer. Hence, the study shows the results for the given database of the 50Hertz transmission control area. This study points out a new way and a new method to ensure the reliable application of this emergency plan to avoid critical situations or blackouts.