An Efficient Network Solver for Dynamic Simulation of Power Systems Based on Hierarchical Inverse Computation and Modification

TL;DR

This paper introduces a hierarchical inverse computation method for power system dynamic simulation, significantly reducing computation time by efficiently updating network solutions during network changes.

Contribution

It presents a novel inverse-based network solver that efficiently updates solutions in EMT simulations, improving over traditional sparse LU factorization methods.

Findings

Reduces computational time in power system simulations

Efficiently updates network solutions after network modifications

Demonstrated on a 179-bus Western Interconnection model

Abstract

In power system dynamic simulation, up to 90% of the computational time is devoted to solve the network equations, i.e., a set of linear equations. Traditional approaches are based on sparse LU factorization, which is inherently sequential. In this paper, an inverse-based network solution is proposed by a hierarchical method for computing and store the approximate inverse of the conductance matrix in electromagnetic transient (EMT) simulations. The proposed method can also efficiently update the inverse by modifying only local sub-matrices to reflect changes in the network, e.g., loss of a line. Experiments on a series of simplified 179-bus Western Interconnection demonstrate the advantages of the proposed methods.