-Doubly Fed Induction Generators (DFIGs)find a great deal of application among variable speed wind turbines because of their advantages like operation at variable speed, ability to produce active and reactive power in all the four quadrants, higher efficiency, and extracting maximum electric power at different velocities of wind with the help of speed variation of the rotor and the usage of con...

LIST OF SYMBOLS L s stator inductance(Primary inductance) L r rotor inductance (Secondary inductance) M mutual inductance Rs stator resistance Rr rotor resistance Rc cable resistance P pole number Vds,Vqs d-axis and q-axis components of the stator voltage vector Vs Vdr,Vqr d-axis and q-axis components of the rotor voltage vector Vr ids, iqs d-axis and q-axis components of the stator current vec...

The cage and reluctance rotors are two major types of rotor structures used in the doubly fed brushless machine (DFBM). In order to study comparatively the effects of different rotor structure on the DFBM, a prototype machine has been specially designed and built. The experimental parameter and performance comparisons between the axially laminated anisotropic (ALA) and cage-rotor machines are p...

In this paper, condition monitoring of a geared rotor system using finite element (FE) model updating and particle swarm optimization (PSO) method is onsidered. For this purpose, employing experimental data from the geared rotor system, an updated FE model is obtained. The geared rotor system under study consists of two shafts, four bearings, and two gears. To get the experimental data,  iezoel...

Hydrokinetic turbines, targeting the kinetic energy of fast-flowing currents, are under development with some turbines already deployed at ocean sites around the world. It remains virtually unknown as to how these technologies affect fish, and rotor collisions have been postulated as a major concern. In this study the effects of a vertical axis hydrokinetic rotor with rotational speeds up to 70...

Gaussian processes prior model methods for data analysis are applied to wind turbine time series data to identify both rotor speed and rotor acceleration from a poor measurement of rotor speed. In so doing, two issues are addressed. Firstly, the rotor speed is extracted from a combined rotor speed and generator speed measurement. A novel adaptation of Gaussian process regression based on two in...

This work deals with the application of an active unbalance compensation scheme for a rotor-bearing system by simultaneously using two control strategies, consisting in the synthesis of a dynamic stiffness controller and the acceleration scheduling for the rotor speed. The rotor-bearing system consists of an asymmetrical Jeffcott-like rotor system with a servomechanism to position a sliding bea...

Abstract: An innovative design of a magnetic coupler for shaft speed amplification is proposed and verified by experiments. The structure of the proposed magnetic coupler is similar to an infinite-stage gearbox. In addition, the mathematical model of flux density is derived to look into the equation of adjustable gear ratio and effect of speed amplification. Moreover, two sets of experiments, n...

air spindles are one of the main elements of precise machine tools. vibration of these spindles is one of the vital issues necessary for investigation. among parameters which influence air spindle vibrations are rotational speed, compression air method, input nozzle diameter, air gap pressure. in this study using ansys, the effects of air gap thickness on air spindle vibrations have been invest...