Cui, HantaoAli, Ahmad2025-01-132025-01-132024-07https://hdl.handle.net/20.500.14446/345753Transient analysis is essential for understanding the behavior of power systems under various contingencies. However, due to the size and complexity of power systems, coupled with their wide timescale dynamics, detailed transient analysis is often computationally prohibitive. Consequently, simplified device models are typically used for large-scale analysis.This thesis investigates the potential of dynamic phasor (DP) based modeling to accelerate simulation speeds while retaining detailed models. Various DP formulations exist in the literature, and this work aims to consolidate these methods and revisit the theoretical foundations of DP-based schemes. To accelerate transient analysis, we combine DP-based modeling with adaptive time-stepping in numerical integration. This approach achieves a computationally efficient simulation framework without losing detail while maintaining high numerical accuracy. Our analysis demonstrates that DP-based modeling can achieve varying levels of detail in simulations without requiring model-level modifications. To explore this framework, a simulation platform using the Julia programming language is developed. Numerical issues impacting the computational stability of the simulation are identified, and remedial strategies are presented. A validation case study using the single-machine infinite-bus system is conducted, with results compared to the electromagnetic transient simulation tool PSCAD and quasi-steady-state (QSS) simulation tool ANDES. An additional case study using the IEEE-14 bus system is performed. The results indicate that DP-based modeling achieves computational speeds comparable to QSS simulation tools, with highly accurate simulation results. This suggests that detailed information about system trajectories can be obtained using DP-based modeling framework with equal or less computational effort as compared to QSS simulation.application/pdfCopyright is held by the author who has granted the Oklahoma State University Library the non-exclusive right to share this material in its institutional repository. Contact Digital Library Services at lib-dls@okstate.edu or 405-744-9161 for the permission policy on the use, reproduction or distribution of this material.Thesisadaptive time steppingdynamic phasorstime domain simulationtransient analysis