With power designers always demanding for faster switches, electromagnetic interference has become an issue of primary concern. As known, the commutation transistors is main cause noise, which can be worsened by presence unwanted oscillations superimposed onto switching waveforms. This work proposes a solution to mitigate caused turn-on transistor exploiting its source inductance plus external ...

Ground state of the dissipative two-state system is investigated by means of the Lanczos diagonalization method. We adopted the Hilbert-space-reduction scheme proposed by Zhang, Jeckelmann and White so as to reduce the overwhelming reservoir Hilbert space to being tractable in computers. Both the implementation of the algorithm and the precision applied for the present system are reported in de...

Global gyrokinetic toroidal code (GTC) is used to study the low-frequency modes in tokamaks including geodesic acoustic mode (GAM) and beta-induced Alfvén eigenmode (BAE). GAM and BAE have the same frequency due to the geodesic curvature and thermal particle compressibility in toroidal plasmas. Important new insights include: the collisionless damping rate of the GAM is greatly enhanced by trap...

This paper presents a new strategy based on Multi-stage Fuzzy (MSF) PID controller based on Artificial Bee Colony (ABC) for damping Power System Stabilizer (PSS) in multi-machine environment. The recent studies in artificial intelligence demonstrated that the ABC optimization is strong intelligent method in complicated stability problems. Also, finding the parameters of PID controller in power ...

This paper presents a new strategy based on Multi-stage Fuzzy (MSF) PID controller based on Artificial Bee Colony (ABC) for damping Power System Stabilizer (PSS) in multi-machine environment. The recent studies in artificial intelligence demonstrated that the ABC optimization is strong intelligent method in complicated stability problems. Also, finding the parameters of PID controller in power ...

Low-frequency oscillations have been reported in several weak-grids-connected voltage-source-converter(VSC) systems. Although efforts devoted to understanding the parametric and sensitivity impact of VSC controller gains, a general formulation oscillation mechanism is still missing. Using transfer function dynamic modelling approach, we find that outer loop active power control's bandwidth main...

A one-dimensional nonlinear model of the so-called upper hybrid oscillations in a magnetoactive plasma is investigated taking into account electron-ion collisions. It known that both presence an external magnetic field strength B0 and sufficiently large collisional factor ν help suppress formation finite-dimensional singularity solution (breaking oscillations). Nevertheless, suppression mechani...

The supplementary control of the UPFC can significantly enhance the damping of interconnect power systems. However, the conventional controller designed based on a linearized model cannot provide adequate damping signal over a wide range of operation points. In this paper, a fuzzy controller is designed as the substitute of the conventional controller. The parameters of the fuzzy controller are...

Reports azd Memorazda No. 3 o I 4" ]azu ry, 1954 Summary.-A specially designed rudder has been fitted to a Vampire Mk. 5 to act as an aerodynamic yaw damper. Flight tests show that the damping of the lateral oscillation has been substantially increased in consequence a logarithmic decrement greater than unity being attained even at 40,000 it altitude. This is a considerable improvement on the r...

This paper shows how globally attractive limit cycle oscillations can be induced in a system with a nonlinear feedback element. Based on the same principle as the Van der Pol oscillator, the feedback behaves as a negative damping for low velocities but as an ordinary damper for high velocities. This nonlinear damper can be physically implemented with a continuous variable transmission and a spr...