A variable-speed, constant-pitch wind turbine was investigated to evaluate the feasibility of constraining its rotor speed and power output without the benefit of active aerodynamic control devices. A strategy was postulated to control rotational speed by specifying the demanded generator torque. By controlling rotor speed in relation to wind speed, the aerodynamic power extracted by the blades...

A centrifugal method for ultrarapid freezing of cells and subcellular particles has been developed, in which small droplets are centrifuged at high speed through liquid nitrogen. When material such as water or blood was injected from a sYI·inge into a rotor, increased rotor speeds gave progressively smaller frozen droplets. Droplet size of materials introduced from a sprayer was uniform, smalle...

In this research paper, the performance of an air-cored axial flux permanent magnet synchronous generator is evaluated for low speed, direct drive applications using 3D finite element modeling and experimental tests. The structure of the considered machine consists of double rotor and coreless stator, which results in the absence of core losses, reduction of stator weight and elimination of cog...

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...

BECKMAN stressing. ESP allows rotor speed to be reduced automatically before precipitation can occur. Since the time required for gradient formation decreases with faster rotor speeds, this approach results in more rapid separations. In general, for fixed angle rotors, rotor speed is limited by the need to avoid precipitation of the gradient salt at the bottom of the tube, where the concentrati...

in this research, the steady-state flow filed around a 3d body and rotor configuration of the robin helicopter is simulated. the rotor is modeled by an actuator disk. for this purpose, an annular computational domain replaces the rotor and some modeled source terms are added to the momentum equations. this modeling of rotor considerably speed up computational time. the flow field over this heli...

A sensorless algorithm was developed to predict rotor speeds in an electric three-phase induction motor. This sensorless model requires a measurement of the stator currents and voltages, and the rotor speed is predicted accurately without any mechanical measurement of the rotor speed. A model of an electric vehicle undergoing acceleration was built, and the sensorless prediction of the simulati...

Variable-speed, fixed-pitch wind turbines are required to optimize power output performance without the aerodynamic controls. A wind turbine generator system is operated such that the optimum points of wind rotor curve and electrical generator curve coincide. In order to obtain maximum power output of a wind turbine generator system, it is necessary to drive the wind turbine at an optimal rotor...

This paper presents a detailed study of the extended Kalman filter (EKF) for estimating the rotor resistance and rotor speed of an induction motor drive. The overall structure of the EKF is reviewed and the various system vectors and matrices are defined. By including the rotor resistance and rotor speed as a state variables, the EKF equations are established from a discrete two-axis model of t...

Abstract: This paper presents an exact input-output linearization control scheme for rotor speed and rotor flux control of induction motor drive. In this scheme the motor model, is described in the fixed stator frame, and it is linearized, using exact inputoutput linearization technique, allowing a decoupled control of rotor flux and torque. To avoid the use of mechanical sensor, the rotor spee...