Numerical Oscillation Suppression of Electromagnetic Transient Simulation Based on Eigenvalue Analysis

This paper describes and replicates the common issue of numerical oscillations in the Electromagnetic Transients Simulation. It introduces existing methods for suppressing numerical oscillations and focuses on analyzing the most widely used Critical Damping Adjustment (CDA) and its limitations in terms of suppression effectiveness. The study investigates the eigenvalues of electromagnetic transient models by the implicit trapezoidal and backward Eulerian methods respectively and analyzes the nature and causes of numerical oscillations from the eigenvalue perspective. Based on this analysis, a new method for suppressing numerical oscillations, grounded in eigenvalue analysis, is proposed. This method can determine the minimum number of backward Eulerian steps required to suppress this numerical oscillation from the electromagnetic transient eigenvalues of the circuit network in advance. Compared to the CDA method, this approach can more effectively suppress numerical oscillations while having a lesser impact on computational accuracy, thereby enhancing the accuracy and reliability of the simulation.