Power-Flow Model and Steady-State Analysis of the Hybrid Flow Controller

This paper introduces a hybrid flow controller (HFC) as a new member of flexible ac transmission system (FACTS) controllers for steady-state and power-flow control of power transmission lines. HFC is a hybrid compensator (i.e., provides series and/or shunt compensation). Structurally, an HFC unit is composed of a mechanically switched phase-shifting transformer, a mechanically switched shunt capacitor, and multimodule, series-connected, thyristor-switched capacitors and inductors. This paper describes the steady-state operation, single-phase equivalent circuit, power-flow model, and $V\hbox{-}I$ and $P\hbox{-}Q$ characteristics of the HFC. This paper highlights the steady-state technical features of the HFC for power-flow control of a study system and also provides a quantitative comparison of the HFC, UPFC, and PST.