Weakly damped power swings are one of the main problems endangering secure operation of power systems. This paper presents two methods , based on the use of nonlinear system model , to improve damping of power swings using UPFC. A statevariable control strategy has been derived using local available signals of real and reactive power. The results of simulation tests of two control methods, unde...

The unified power flow controller (UPFC) is a typical FACTS (Flexible AC Transmission Systems) device that is capable of instantaneous control of transmission line parameters. This paper presents the transient model and control system of UPFC. The presented control system enables the UPFC to following the exchanges of line active and reactive power reference values, regulating the DC link and b...

In this paper the performance of unified power flow controller is investigated in controlling the flow of po wer over the transmission line. Voltage sources model is utilized to study the behaviour of the UPFC in regulating the active, reactive power and voltage profile. This model is incorporated in Newton Raphson algorithm for load flow studies. Simultaneous method is employed in which equati...

In this paper a multi objective optimal power flow (OPF) is obtained by using BAT search algorithm (BAT) with Unified power flow controller (UPFC). UPFC is a voltage source converter type Flexible Alternating Current Transmission System (FACTS) device. It is able to control the voltage magnitudes, voltage angles and line impedances individually or simultaneously. UPFC along with BAT algorithm i...

In this paper, the state estimation (SE) problem is formulated as a general nonlinear programming problem with equality constraints and boundary limits on the state variables. The objective of this paper is to incorporate the Unified Power Flow Controller (UPFC) into the SE algorithm. UPFC has the potential to independently control the voltage, active and reactive power flows in the system. In ...

The main objective of this paper is to find the optimal location and control parameters settings of Unified Power Flow Controller (UPFC) with regard to power loss minimization. The proposed algorithm is based on steady state power injection model of UPFC. In this paper, two Evolutionary optimization techniques, namely Differential Evolution Algorithm (DE) and Genetic Algorithm (GA) are employed...

The use of the supplementary controllers of a unified power flow controller (UPFC) to damp low frequency oscillations in a weakly connected system is investigated. The potential of the UPFC supplementary controllers to enhance the dynamic stability is evaluated by measuring the electromechanical controllability through singular value decomposition (SVD) analysis. Individual designs of the UPFC ...

This article presents a novel configuration for unified power flow controller (UPFC) comprising modular multilevel cascaded converter (MMCC) with full-bridge inverter. The MMCC has one end of each phase-leg shunt-connected to the transmission line. other connects in parallel primary terminals series line transformer, and ac output dc–ac submodules are flying capacitor converters. UPFC is compar...

This study presents a study of the application of a Unified Power Flow Controller (UPFC) to control power transmission, generator terminals voltage and better damping of Low Frequency Oscillation (LFO) in Single-Machine Infinite-Bus (SMIB) power system. The UPFC integrates properties of both shunt and series compensations and can effectively alter power system parameters in a way that increases...

We deal with the effect of Unified Power Flow Controller UPFC installation on the objective function of an electricity market. Also this paper proposes a Novel UPFC modelling in OPF which facilities the consideration of the impact of four factors on power market. These include the series transformer impedance addition, the shunt reactive power injection, the in-phase component of the series vol...