Low Frequency Oscillations (LFO) occur in power systems because of lack of the damping torque in order to dominance to power system disturbances as change in mechanical input power. In the recent past Power System Stabilizer (PSS) was used to damp LFO. FACTs devices, such as Unified Power Flow Controller (UPFC), can control power flow and increase transient stability. So UPFC may be used to dam...

In this paper a linearized Heffron-Philips model of a Single Machine Infinite Bus power system with a Fuzzy Logic Power System Stablizer (PSS) is developed. The designed fuzzy-based PSS adjusts two inputs by appropriately processing of the input angular speed and angular acceleration signal, and provides an efficient damping. The behavior of the SMIB system with & without PSS has been compared/...

The voltage source converter (VSC) excitation system is a novel excitation system based on pulse-width modulation (PWM) voltage source converter, which is proposed as improved alternatives to the conventional thyristor excitation systems. This paper aims to provide theoretical confirmation of power system stability enhancement by the VSC excitation system. The reactive current injected to gener...

Abstract: Power system stabilizers (PSSs) are widely used for suppressing low frequency oscillations in practical power systems. However, according to the requirement of the “guide for setting test of power system stabilizer” of China, PSS gain is limited to no more than 1/3 of its critical gain. As a result, PSSs may not provide enough damping to the inter-area mode oscillations. Through analy...

Central core disease (CCD) is a human congenital myopathy characterized by fetal hypotonia and proximal muscle weakness that is linked to mutations in the gene encoding the type-1 ryanodine receptor (RyR1). CCD is thought to arise from Ca(2+)-induced damage stemming from mutant RyR1 proteins forming "leaky" sarcoplasmic reticulum (SR) Ca(2+) release channels. A novel mutation in the C-terminal ...

This paper investigates the application of Particle Swarm Optimization (PSO) technique for coordinated design of a Power System Stabilizer (PSS) and a Thyristor Controlled Series Compensator (TCSC)-based controller to enhance the power system stability. The design problem of PSS and TCSC-based controllers is formulated as a time domain based optimization problem. PSO algorithm is employed to se...

In this paper, the modified linearized Phillips-Heffron model is utilized to theoretically analyze asingle-machine infinite-bus (SMIB) installed with SSSC. Then, the results of this analysis are used forassessing the potential of an SSSC supplementary controller to improve the dynamic stability of apower system. This is carried out by measuring the electromechanical controllability through sing...

OBJECTIVE Some observational studies have suggested an association between the use of hormonal contraceptives (HC) and HIV acquisition. One major concern is that differential misreporting of sexual behavior between HC users and nonusers may generate artificially inflated risk estimates. STUDY DESIGN We developed an individual-based model that simulates the South African HIV serodiscordant cou...

Glover, Louise, James J. A. Heffron, and Kay Ohlendieck. Increased sensitivity of the ryanodine receptor to halothane-induced oligomerization in malignant hyperthermia-susceptible human skeletal muscle. J Appl Physiol 96: 11–18, 2004. First published September 5, 2003; 10.1152/japplphysiol.00537.2003.—Mutations in the skeletal muscle RyR1 isoform of the ryanodine receptor (RyR) Ca -release chan...

To the Editor—Pneumococcus is a venerable microorganism with an amazingly rich history. Those of us who study this organism should constantly examine our present findings in light of the wealth of previous literature. I am concerned when investigators draw conclusions from their own excellent but potentially limited data without referring to or noting discrepancies with that earlier body of kno...