A Multi-Decomposition Approach for Accelerated Time-Domain Simulation of Transient Stability Problems

Time-domain simulation (TDS) is the most accurate and reliable method for solving transient stability problem. This approach relies on the solution of nonlinear differential-algebraic equations (DAEs) using numerical integration, wherein a system of nonlinear equations is solved at each integration time step. Very DisHonest Newton (VDHN) method is one of the fastest available approaches for solving the system of nonlinear equations in the TDS. However, VDHN does not guarantee convergence and its sequential nature makes it difficult to take advantage of available multicore processors. This paper presents a new multi-decomposition approach (MDA) to achieve fast TDS, wherein the nonlinear system of DAEs is decomposed into three linear subsystems. An adaptive scheme is developed for updating the linear subsystems to ensure that approximation remains sufficiently accurate. The linear subsystems can be solved in parallel using multi-processor architecture. The MDA is demonstrated using IEEE 145-bus test system, and the results are verified against a commercial transient stability problem, Powertech Labs´ DSATools.