Abstract

Transmission assets are traditionally treated as static assets in power systems operational studies. Past research efforts have pointed out the advantages of treating the transmission network topology as a flexible asset; however, the flexibility in the transmission system is not fully modeled in existing operational tools (e.g., security constrained unit commitment, security constrained economic dispatch, contingency analysis). Although topology control (TC) is currently being used as a corrective mechanism to relieve violations in the system, the determination of the corrective actions are primarily determined based on ad-hoc methods. Most of the previous studies on TC are based on a DC framework and are tested on small systems. It is very important to test the switching solutions on an AC framework and on actual systems in order to get a real estimate of the actual benefits that could be obtained through TC. In this paper, an AC based N-1 contingency analysis is performed on the Tennessee Valley Authority (TVA) system. The fast decoupled power flow algorithm is used to solve the base case, the contingency case and to evaluate the switching solutions through a complete enumeration procedure. The objective of this research is to estimate the maximum reliability improvement that could be achieved through TC on an actual system by testing it on an AC setting. The TC actions on the TVA system are tested for its ability to reduce voltage violations as well as the thermal violations in the network at a post contingency stage. In the implemented approach, the generators are re-dispatched based on their available reserve capacity for generator contingencies unlike using the traditional assumption of a slack bus, where the loss of a generator is picked up by the slack bus. The results are promising and future work will analyse the effect of the switching solutions on the system stability.

Index Terms

Contingency analysis, Corrective topology control, Fast decoupled AC power flow, Transmission switching.

Cite this paper:

Xingpeng Li, Pranavamoorthy Balasubramanian, Mojdeh Abdi-Khorsand, Akshay S. Korad, and Kory W. Hedman, “Effect of Topology Control on System Reliability: TVA Test Case,” CIGRE US National Committee Grid of the Future Symposium, Houston, TX, USA, Oct. 2014.

link to paper PDF copy from CIGRE website:

http://cigre-usnc.org/wp-content/uploads/2015/06/Effect-of-Toplogy-Control-on-System-Reliability-TVA-Test-Case.pdf