Robust Steady State Analysis of the Power Grid

A robust methodology for obtaining the steady-state solution of the power grid is essential for reliable operation as well as planning of the future transmission and distribution grid. At present, disparate methods exist for steady-state analysis of the transmission (power flow) and distribution power grid (three-phase power flow). All existing alternating current (AC) power flow and three-phase power flow analyses formulate a non-linear problem that generally lacks the ability to ensure convergence to the correct physical solution from an arbitrary set of initial guesses. In this paper, we demonstrate that our equivalent circuit formulation approach can model both the positive sequence model of the transmission grid and three-phase model of the distribution grid without loss of generality. Moreover, when combined with novel circuit simulation techniques, it can robustly solve for the steady-state solution for both these network models independent of the choice of initial conditions. Examples for positive sequence transmission and three-phase distribution systems, including 75k+ nodes Eastern Interconnection transmission test cases and 8k+ nodes taxonomy distribution test cases, are solved from arbitrary initial guesses to demonstrate the robustness of our approach.