Enhancement of fault ride-through (FRT) capability and subsequent improvement of rotor speed stability of wind farms equipped with doubly fed induction generator (DFIG) is the objective of this paper. The objective is achieved by employing a novel FRT scheme with suitable control strategy. The proposed FRT scheme, which is connected between the rotor circuit and dc link capacitor in parallel wi...

Broken rotor bars in induction motors can be detected by monitoring any abnormality of the spectrum amplitudes at certain frequencies in the motor current spectrum. Broken rotor bar fault detection schemes should rely on multiple signatures in order to overcome or reduce the effect of any misinterpretation of the signatures that are obscured by factors such as measurement noises and different l...

On the rotor comprehensive fault simulation testbed, characteristics of acoustic emission signal of different crack rotors in various depth and conditions are analyzed by the acoustic emission extraction experiment. The noiseeliminating method of the acoustic emission signal was researched by the wavelet packet technique, the characteristics of acoustic emission signal of the rotor crack was al...

this article is for the coupling fault diagnosis of rotor system, and does in-depth analysis of the rotor unbalance and misalignment, and the fault formed by the coupling of these two. Through research, Rotor Coupling was found filled with rich features. In this paper, Wavelet packet de-noising ideas being introduced to the local Fisher discriminant analysis (LFDA), a new method of fault diagno...

ABSTRACT Motor current signature analysis has been successfully used for fault diagnosis in induction motors. However, this method does not always achieve good results when the speed or the load torque is not constant, because this cause variation on the motor slip and fast Fourier transform problems appear due to non-stationary signal. This paper experimentally describes the effects of rotor b...

Disk Type Variable Reluctance (DTVR) resolvers have distinguished performance under run out fault comparing to conventional sinusoidal rotor resolvers. However, their accuracy under inclined rotor fault along with different types of eccentricities includes static and dynamic eccentricities are questioned. Furthermore, due to thin copper wires that are used for signal and excitation coils of res...

Induction motors (IMs) are commonly used in various industrial applications. A spectrum synch (SS) technique is proposed in this chapter for early IM defect detection using electric current signals; fault detection in this work will focus on defects in rolling element bearings and rotor bars, which together account for more than half of IM imperfections. In bearing fault detection, the proposed...

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) ...

Broken rotor bars in an induction motor create asymmetries and result in abnormal amplitude of the sidebands around the fundamental supply frequency and its harmonics. Applying a spectrum analysis technique on motor current and inspecting the spectrum amplitudes at the broken rotor bar specific frequencies for abnormality is a well-known procedure for broken rotor bar fault detection and diagno...

The faults of rotating machinery monitored by fixing the sensors on rotor directly brings some problems such as difficulty in fixing the sensors, poor universality and so on, while it brings some advantages such as rapidness, convenience and good universality and so on by fixing the sensors on the base. Since the base is far away from the fault source, the collected vibration signals are relati...