University of Mohaghegh Ardabili Journal of Operation and Automation in Power Engineering 2322-4576 9 2 2021 08 01 A Practical Approach for Coordinated Transmission Switching and OLTCs’ ‎Tap Adjustment: DIgSILENT-Based Improved PSO Algorithm 103 115 1036 10.22098/joape.2021.7378.1533 EN A. Bagheri Department of Electrical Engineering, Faculty of Engineering, University of Zanjan, Zanjan, Iran Planning and Research Deputy, Zanjan Regional Electric Company, Zanjan, Iran A. Rabiee Department of Electrical Engineering, Faculty of Engineering, University of Zanjan, Zanjan, Iran Planning and Research Deputy, Zanjan Regional Electric Company, Zanjan, Iran S. Galavani Planning and Research Deputy, Zanjan Regional Electric Company, Zanjan, Iran Faculty of Electrical and Computer Engineering, Urmia University, Urmia, Iran H. Yassami Planning and Research Deputy, Zanjan Regional Electric Company, Zanjan, Iran Saba Power Plant, Operation and Maintenance Company, Tehran, Iran A. Moeini Department of Electrical Engineering, Faculty of Engineering, University of Zanjan, Zanjan, Iran Hydro Quebec Research Institute, Quebec, Canada Journal Article 2020 06 18 Transmission lines switching and tap adjustment of power transformers are short-term alternatives to enhance the flexibility of power system operation. By a proper implementation of these alternatives, the operational problems such as lines congestion, bus voltage violations and excessive power losses can be alleviated. Traditionally, these two alternatives are applied separately due to the complexity of their simultaneous implementation as well as their coordination. In this paper, a DIgSILENT-based improved particle swarm optimization (IPSO) algorithm is proposed to implement the transmission switching and coordinated voltage control of power transformers, concurrently. The IPSO is implemented in DPL environment of Powerfactory-DIgSILENT, as a powerful software package commonly used by the electrical utilities. The proposed approach is applied to IEEE-14 bus system and the real transmission network of Zanjan Regional Electric Company (ZREC) located in Iran, in different scenarios considering all the existing practical constraints. The obtained results verify the effectiveness of the presented approach. https://joape.uma.ac.ir/article_1036_fbbfd843633bcd1e3eebff1c998a9731.pdf