The rotor configuration of the brushless doubly fed induction generator (BDFIG) plays an important role in its performance. In order to make the magnetomotive force (MMF) space vector in one set rotor windings to couple both magnetic fields with different pole-pair and have low resistance and inductance, this paper presents a novel wound rotor type for BDFIG with low space harmonic contents. In...

The membrane domain of rotary ATPases (Fo/Vo/Ao) contains a membrane-embedded rotor ring which rotates against an adjacent cation channel-forming subunit during catalysis. The mechanism that allows stabilization of the highly mobile and yet tightly connected domains during operation while not impeding rotation is unknown. Remarkably, all known ATPase rotor rings are filled by lipids. In the cry...

Title of dissertation: DESIGN AND PERFORMANCE PREDICTION OF SWASHPLATELESS HELICOPTER ROTOR WITH TRAILING EDGE FLAPS AND TABS Jaye Falls, Doctor of Philosophy, 2010 Dissertation directed by: Professor Inderjit Chopra Department of Aerospace Engineering This work studies the design of trailing edge controls for swashplateless helicopter primary control, and examines the impact of those controls ...

The objective of the research is to diminish unwanted forces generated by rotation and unbalanced rotor mass on the rotor of an electrical machine. These forces, dependent on rotational speed, cause vibration that, when occurring in the machine’s natural frequency, causes severe problems. Extra windings are built in the stator of the machine, and they are supplied with current to create an oppo...

According to tradition, permanent maglev cannot achieve stable equilibrium. The authors have developed, to the contrary, two stable permanent maglev impeller blood pumps. The first pump is an axially driven uni-ventricular assist pump, in which the rotor with impeller is radially supported by two passive magnetic bearings, but has one point contact with the stator axially at standstill. As the ...

In this paper a numerical study is presented with the aim of evaluating the performance output of three Vertical Axis Wind Turbine (VAWT) configurations. Here using Computational Fluid Dynamics (CFD) a two-dimensional Multi Reference Frame (MRF) approach has been used to perform steady state simulations. For this purpose an inlet velocity of 4m/s has been used along with rotor blade Tip Speed R...

One of the most critical problems in induction motor drive is the knowledge of the current value of some induction motor parameters such as the rotor time constant, which depends strongly on temperature and frequency. This problem won’t be easy to solve because of the high coupling between parameters in the nonlinear induction motor model. In order to determine the rotor time constant, this pap...

This paper extends the prescribed wake vortex lattice/line method (VLM) to perform aerodynamic analysis and optimization of dual-rotor wind turbines (DRWTs). A DRWT turbine consists of a large, primary rotor placed co-axially behind a smaller, secondary rotor. The additional vortex system introduced by the secondary rotor of a DRWT is modeled while taking into account the singularities that occ...

The performance of an Indirect Rotor Field-Oriented Control (IRFOC) scheme for Induction Motors (IMs) is strongly dependent on the motor parameters especially, rotor resistance. As such, to ensure high performance drive system, the variation of the rotor resistance due to the temperature increase need to be estimated based on the available terminal variables. However, the algorithm used to esti...

The concept of a vertical-axis spiral wind rotor is proposed and implemented in the interest of adapting it to air flows from all directions and improving the rotor’s performance. A comparative study is performed between the proposed rotor and conventional Savonius rotor. Turbulent flow features near the rotor blades are simulated with Spalart-Allmaras turbulence model. The torque coefficient o...