A study of the voltage distribution for the interconnection of power grids

Abstract

A good understanding of the voltage profile of an interconnected power grid is important for supporting the decision on the interconnection of power grids in terms of power quality and power transmission security, especially for developing countries when making interconnection decisions, with a limited amount of expensive voltage compensation devices. In this paper, a statistic method is presented for assessing the change in the system-wide voltage profile before and after the interconnection of large-scale power grids, which provides additional useful information to support the existing interconnection studies. In this method, the skewness and kurtosis are used to characterize the change in the voltage distribution of the non-generation buses before and after the interconnection. Furthermore, a study is presented to show that the skewness and kurtosis may be essential for a statistical analysis of the change in the system-wide voltage profile, as its distribution might be skewed, particularly for the non-generator buses without automatic voltage regulators or other compensation devices. The demonstration of this method is also provided.