Comparison of Sen Transformer and Unified Power Flow Controller on Spot Price Variation of Real and Reactive Power under Maximum Loadability Condition

Abstract

In competitive electricity markets, the locational marginal price, or spot price, of power has become an important indicator of competitiveness and market efficiency. System operators throughout the world utilize the locational marginal price of active power for congestion management, auctioning of transmission rights, and pricing of transmission service. Recent studies have indicated the locational marginal price of reactive power has a role to play in improving system reliability and pricing voltage support services. In this article, a study of variation in locational marginal price of active and reactive power under normal and maximum loadability conditions has been carried out. A two-step optimization problem of maximizing system loadability and social welfare is proposed. Recently, there has been considerable interest in the role of power flow controllers in competitive electricity markets. In this article, a comparative study of impact of power flow control devices, such as the unified power flow controller and Sen transformer, on locational marginal prices of active and reactive power under maximum loadability condition has been carried out. The placement of these power flow control devices in a system has been obtained using mixed-integer non-linear programming. The study has been conducted on two IEEE test systems—14- and 57-bus—for a pool market model.