Effective Modeling of OUPFC Into Newton-Raphson Power Flow Considering Multi-Control Modes and Operating Constraints

The Optimal Unified Power Flow Controller (OUPFC) is an efficient series-shunt controller that is incorporated to system to control the power flow through the transmission lines. Modeling of such controller is a challenge task due the required complex modifications of the Newton Raphson power (NR) flow to consider the parameters of the OUPFC. The aim of this paper includes (1) presenting an efficient novel model of the OUPFC into NR power flow, (2) avoiding the complicities of modeling the parameters of the OUPFC into power flow solution, (3) multi-control modes of the OUPFC is established to control the active and reactive powers concurrently or separately and, (4) handling the violation of the operating constraints by using developed methods. The proposed model is based on the power injection representation where the parameters of the OUPFC are represented as injected loads as a function of the pre-requested control variables (specified values). Therefore, the complicities of including its parameters are reduced. The developed methods for handling the violations of the operating constraints are based on modifying the specified values as a function of the maximum limits of the operating constraints. The proposed OUPFC model and the developed constraints handling methods are implemented on IEEE 14-bus, IEEE 30-bus, IEEE 57-bus and IEEE 118-bus test systems. The simulation results verified the feasibilityand robustness of the presented model into load flow analysis. in addition, effectiveness of the proposed approaches forhandling the operating constraints of OUPFC.