Congestion management and determination of optimal grid expansion and retreat strategies using a modified boundary load flow method

The conventional boundary load flow method is an algorithm calculating interval bounds and distribution functions of nodal voltages or deduced values of electric power systems at which density functions of all influencing variables are known. In contrast, the modified boundary load flow was developed to estimate state space bounds of distribution grids which are not entirely observable. But the field of application is not limited to determining voltage bounds and equipment overstressing. Instead, the modified boundary load flow can be used to detect congestions and furthermore to uniquely determine the contribution of each load and generator which is highly relevant to transmission system operators. Due to the proposed method is able to trace power flows throughout the grid it additionally enables operators the find optimal grid expansion and retreat strategies for future load scenarios. In this paper the modified boundary load flow and its original intention is presented. After that the adoptions for the congestion detection and the determination of future grid expansion and retreat strategies are shown.