Variable time-step for power grid EMT simulations


Matehkolaei M. J., Mahseredjian J., Bruned B., KARAAĞAÇ U.

ELECTRIC POWER SYSTEMS RESEARCH, vol.263, 2027 (SCI-Expanded, Scopus)

  • Publication Type: Article / Article
  • Volume: 263
  • Publication Date: 2027
  • Doi Number: 10.1016/j.epsr.2026.113657
  • Journal Name: ELECTRIC POWER SYSTEMS RESEARCH
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, Environment Index, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
  • Middle East Technical University Affiliated: Yes

Abstract

This paper presents a new variable time-step method for the electromagnetic transient (EMT) simulation of power systems. Trapezoidal discretization with a constant time-step is commonly employed in EMT simulations of power systems. During an EMT simulation, power systems typically encounter high-frequency transients that demand small time-steps for accuracy, as well as low-frequency and steady-state conditions that allow larger time-steps for efficiency. With a fixed time-step, either the simulation accuracy or speed is compromised, and achieving a trade-off is not feasible for all cases. Consequently, this paper proposes a novel variable time-step strategy for maintaining both simulation accuracy and speed. The performance of the proposed method is verified through the WECC 240-bus system.