Recent trends in power systems are mostly undergoing research in the area of widespread failures. With the increase in power demand, operation and planning of large interconnected power system are becoming more complex, so power system will become less secure and stable. Operating environment, conventional planning and operating methods can leave power system exposed to instabilities. Voltage s...

Transmission pricing is an important issue in view of increased deregulation. Purpose of pricing is to recover cost of transmission encourage efficient use and investment. Wheeling charges for power transmission can be reduced by FACTS devices as they are effective means of controlling the power flow in the network. The unified power flow controller (UPFC) integrates properties of both shunt an...

Among all FACTS devices, the unified power flow controller (UPFC) is considered to be the most versatile device. This is due to its capability to control all the transmission system parameters (impedance, voltage magnitude, and phase angle). With the growing interest in UPFC, the attention to develop a mathematical model has increased. Several models were introduced for UPFC in literature for d...

This paper explores the use of a Unified Power Flow Controller (UPFC) for global power system control. Coordinated control schemes are assigned to the UPFC, Power System Stabilizer (PSS) and generator excitation to maintain transient stability and voltage stability following a disturbance. The extension to use of UPFC in damping inter-area oscillation is also considered. Under the proposed coor...

Flexible ac transmission systems (FACTS) controllers, which can effectively enhance the loadability of the network by controlling the power flows, must be placed optimally due to their high cost. This paper proposes a mixed integer based non-linear programming approach for optimal location of UPFC for system loadability enhancement in competitive electricity markets. The method accounts for ac ...

Optimal power flow (OPF) study is conducted on a power system to achieve one of the following objectives: cost/loss minimization or available transfer capability (ATC) calculation in a deregulated environment. Distributed generation (DG) is a small source of electric power conversion from nonconventional energy sources and Hybrid DGs which often the most cost-effective and reliable way to produ...

This paper presents a particle swarm optimization (PSO)-based neuro-sliding mode controller for the transient stability enhancement of multimachine power systems with unified power flow controller (UPFC). The UPFC is modeled as controllable loads. These controllable parameters are obtained using the sliding mode control (SMC) strategy. A PSO-based single neuron controller is used to adapt the p...

Power stability is an important issue that is becoming increasingly important to an power systems at all levels. We are unable to achieve the stability of the system due to some factors. Low frequency oscillation’s is one of the major factors that affect the transmission line capacity. Traditionally power system stabilizers(PSS) are being used to damp these inevitable oscillations. In advanced ...

This paper presents a method for designing of proportional-integral-derivative (PID) controller based on unified power flow controller (UPFC) using chaotic harmony search algorithm (CHS) for damping of low frequency oscillations (LFO) in a power system. The main aim of this paper, optimization of selected gains with the time domainbased objective function which is solved by chaotic harmony sear...