High-Order Exponential Integrator with Network Decoupling for Numerically Efficient Simulation of Large-Scale Power Electronic Systems

Large-scale power electronic converters contain numerous energy storage devices, contributing to high dimensions of system state-space equations. Electromagnetic transient (EMT) simulation involving these large systems presents a significant challenge. This paper proposes a high-order exponential integrator (EI) with network decoupling strategy to achieve rapid simulation of power electronic systems using a variable step-size switching-event driven algorithm. The proposed exponential integrator with network decoupling reduces the size of system matrices to accelerate EMT simulation, while making precomputation of key matrix terms feasible. The proposed EI technique uses high-order derivatives of state-space equations to accommodate large, variable step-sizes. EI is inherently L-stable, making the proposed algorithm well suited for stiff or non-stiff systems alike. A large-scale power electronic system case study is used to demonstrate the numerical accuracy and efficiency of the proposed EI. The simulation runtime of the EI demonstrates a 32fold speedup, compared to a popular simulation toolbox, i.e., Simulink/Simscape Electrical toolbox.