The adaptive sliding-mode observer has been widely used to estimate the rotor flux and rotor speed in inverter-fed sensorless induction motor drives. However, the technique requires setting a priori the sliding-mode observer constants and also knowledge of the induction motor parameters. This particular aspect can cause significant errors in the estimation of the rotor speed used in sensorless ...

In this paper, application of Sliding Mode Control (SMC) technique for an Active Magnetic Bearing (AMB) system with varying rotor speed is considered. The gyroscopic effect and mass imbalance inherited in the system is proportional to rotor speed in which this nonlinearity effect causes high system instability as the rotor speed increases. Transformation of the AMB dynamic model into regular sy...

This thesis presents the design, analysis, and experimental results of a circuit to be used as a position sensor for microfabricated electric motors. The circuit is designed to measure the capacitance between the rotor blades and sensor electrodes implanted into the substrate beneath the rotor. This capacitance typically varies between five and fifteen femtofarads as the rotor turns. Analytic a...

A molecular turnstile based on a hydroquinone luminescent hinge bearing two divergently oriented pyridyl units behaving as a rotor and equipped with a handle composed of a tridentate coordinating site considered as the stator was synthesized and its structure was studied in the solid state by X-ray diffraction on single crystal. Its dynamic behaviour in solution was investigated by 1- and 2-D N...

Abstract: Unbalanced mass identification is important for rotor systems. Current methods normally use sensors, which only detect vibration in two-dimensional (2D) space. Actually, the rotor systems vibrate in three-dimensional directions. In this paper, a non-contact method is developed to identify unbalanced mass of rotor systems in 3D space. A stereo video system with a pair of synchronized h...

Control of a helicopter is complex, and includes cross coupling of forces and balancing of forces. While sophisticated and advanced controllers can achieve stable control, good mechanical design can reduce the problems and hence make tuning the control loops easier. In this paper, we argue that a coaxial-rotor design solves a number of problems that make control of a four-rotor helicopter diffi...

In this paper the design, fabrication and analysis of behavior by full-scale ver-ification testing for the tail rotor blade of composite laminated materials for a heavy transport helicopter is given. The verification test program for the tail rotor blade encompassed static and dynamic test-ing. The static tests of the blade involved experimental evaluation of torsional and flexional blade stif...

The detection of faults in a dynamic system can help to avoid severe damage where system reliability and safety are essential. An induction motor can fail either due to internal faults such as short circuit of motor leads; broken rotor bar and cracked rotor end rings or by external faults such as phase failure, asymmetry of main supply and mechanical overload (Karami et al 2010). Detection and ...

In this paper, grid disturbances like asymmetrical sag and swell faults in phase-A are analyzed for the grid connected DFIG. The dynamic behavior of DFIG is compared and tabulated with results using state error compensators like PI, PI with resonant (PIR) and internal model control (IMC) on rotor side converter (RSC). The RSC is designed analytically with enhanced field oriented control (EFOC) ...

Turbochargers are most widely used in automotive, marine and locomotive applications with diesel engines. To increase the engine performance nowadays, in aerospace applications also turbochargers are used. Mostly the turbocharger rotors are commonly supported over the fluid film bearings. With the operation, lubricant properties continuously alter leading to different load bearing capacities. T...