This paper proposes a restricted earth fault protection based on the wavelet transform (REFW) for detecting ground faults close to transformer neutral point (turn-to-ground faults) and supporting conventional phase differential protection, which presents limitations in this kind of faults. The proposed REFW uses only high-frequency components instead phasor estimation, speeding up detection tur...

This study describes the design and testing of a dual-lane electric drive for a prototype, electromechanically actuated, nose wheel steering system for a commercial aircraft. The drive features two independent motor controllers, each operating onehalf of a dual three-phase motor, resulting in an actuator capable of full performance following an electrical fault. An isolated communications link ...

Wet filament winding technology has been extensively used for the manufacture of rotationally symmetric parts made fiber-reinforced plastics (FRP). As design and modeling FRP-parts require numerous assumptions, deviations between calculated achieved mechanical properties are expected. One aspect that contributes to this discrepancy is assumption a homogeneous rectangular cross-section fiber-ban...

In some key areas, fault-tolerant control is usually needed in order to enable the motor operate continuously fault mode. Given that it difficult detect zero-sequence current of open winding permanent magnet synchronous after phase break occurs, traditional suppression strategy no longer applicable occurs. Therefore, a for common DC bus under proposed this paper. By establishing mathematical mo...

Inter-Turn Short Circuit (ITSC) fault in stator winding is a common Doubly-Fed Induction Generator (DFIG)-based Wind Turbines (WTs). Improper measures the ITSC affect safety of faulty WT and power output Farm (WF). This paper combines derating WTs optimization WF to diminish effect. At turbine level, switching strategy Fault Ride-Through (FRT) adopted ensure that safely operate under fault. far...

The signal in the nature ofsingularity is always caused by mechanical fault of CNC machine tool. It is important to recognize the singularity correctly for mechanical fault diagnosis. This paper deals with the wavelet t ransform and the relation between the modulus maxima and the singularity detection, and based on the excellent property of the Hermitian wavelet, poses the conception that appli...

This paper presents a review on application of wavelet transform for condition monitoring and fault diagnosis of mechanical equipment. The discrete wavelet transform performs a multilevel signal decomposition to extract fault features from the vibration signal. A review on all the literature of condition monitoring using wavelet transform is certainly not possible. The purpose of this review pa...

Power system overvoltages due to switching, lightning and other disturbances are the main problem for designers of the power transformers. Once some frequencies of the incoming surges match with some of the natural frequencies of transformer winding, the resonance phenomenon is expected in transformer winding. The resonant overvoltages may destroy the insulation between turns and cause to insul...