Numerical Accuracy Analysis of Multi-scale Transient Simulation in AC-DC Systems

摘要

For the simulation of diverse transients in ac and dc networks, a multi-scale transients modeling method, which is based on the Hilbert transform and frequency shifting is presented in this paper. It can use different time steps to simulate electromagnetic and electromechanical transients separately within the same study. The simulation scale and simulation speed have been greatly improved by using larger simulation step size in the electromechanical subsystems. To demonstrate the accuracy of a system with different time steps, a formal mathematical analysis validation method is presented. Using this validation method, the proposed modeling method is demonstrated to have better accuracy. Then, a large and complex network with kinds of power electric equipment can be easily, accurately and quickly simulated. The proposed methods are thoroughly demonstrated in a numerical example under steady state and faulty conditions.