The noise emissions of wind turbines lead to extensive problems for manufacturers as the approval process and the development site are influenced. Against this back­ ground the industry requires immediate action. Due to legal requirements and acceptance problems of wind tur­ bines in the population, acoustic emissions are a signifi­ cant issue for manufacturers. Over the last decade the average...

Interaction of the third harmonic magnetic field with the third harmonic current in a five-phase synchronous reluctance motor (SynRM) can produce additional torque. However, it is still not clear about the SynRM power factor and its impact on the associated power converter because of the third harmonic components. Using time-stepping finite-element method, a mathematical model of the SynRM, whi...

In the speed sensorless vector control system, the amended method of estimating the rotor speed about model reference adaptive system (MRAS) based on radial basis function neural network (RBFN) for PMSM sensorless vector control system was presented. Based on the PI regulator, the radial basis function neural network which is more prominent learning efficiency and performance is combined with M...

The condition monitoring of the electrical machines can significantly reduce the costs of maintenance by allowing the early detection of faults, which could be expensive to repair. In this paper some results on non-invasive detection of broken rotor bars in squirrel-cage induction motors are presented. The applied method is the so-called motor current signature analysis (MCSA) which utilises th...

The current paper studies the influence of annular seal flow on the transient response of centrifugal pump rotors during the start-up period. A single rotor system and three states of annular seal flow were modeled. These models were solved using numerical integration and finite difference methods. A fluid-structure interaction method was developed. In each time step one of the three annular se...

Instantaneous angular speed (IAS)-based condition monitoring is an area in which significant progress has been achieved over the recent years. This condition monitoring technique is less known compared to the existing conventional methods. This paper presents model-predicted simulation and experimental results of broken rotor bar faults in a threephase induction motor using IAS variations. The ...

This paper reviews the advantages of substituting die-cast copper for aluminum in the motor rotor. This advance in motor technology has been long sought by the motor industry but short die life due to the high melting point of copper frustrated attempts to manufacture by pressure die casting. The nickel-base alloy hot die technology developed to solve the manufacturing problem is briefly review...

The unbalanced voltages cause negative effects on the doubly fed induction generator (DFIG) such as torque pulsation and increased stator current. Based on the symmetrical component theory, the torque pulsation is the consequence of the interaction of stator and rotor currents of different sequences. This paper presents a control technique to reduce the effect of unbalanced voltages on the DFIG...

Quad-rotor helicopter is an Unmanned Aerial Vehicle (UAV), whose lift is generated by four rotors located on the corner of X-shape. Due to simplicity of its dynamics and its ability to hover, quadrotor helicopter becomes as a popular platform for UAV. Current designs mostly consider a linear model for controller design. In this paper, we derivate nonlinear dynamic equations of the quadrotor UAV...

Considerable progress in development and application of CFD for aeroengine internal flow systems has been made in recent years. CFD is regularly used in industry for assessment of air systems, and the performance of CFD for basic axisymmetric rotor/rotor and stator/rotor disc cavities with radial throughflow is largely understood and documented. Incorporation of three dimensional (3D) geometric...