This paper deals with mechanical fault diagnosis in three-phase induction machines from stator current measurements. According to machine models, mechanical faults lead to amplitude and/or phase modulations of the measured stator current with possibly time varying carrier frequency. The modulation diagnosis requires a univocal definition of the instantaneous phase and amplitude. This is perform...

– In this paper, the authors propose a scheme to react to grid faults. This is based on block control technique using sliding modes. For normal operation the electric torque and the reactive power are controlled; when the fault is incepted the electric torque and the stator current are controlled. The wind turbine is emulated by a DC motor, which is controlled using a discrete time block contro...

Stator interturn faults are one of the most common faults occurring in induction motors. Early detection of interturn short circuit is important to reduce repair costs. Axial leakage monitoring, zero-sequence components, negative sequence current, and motor current signature analysis have been used for fault detection in early states. In the paper, the instantaneous power signature analysis tec...

A transient model for an induction machine with stator winding turn faults is derived using reference frame transformation theory. A state-space representation of the dynamic equations, suitable for digital simulation is provided. Steady-state equivalent circuits are derived, from which the sequence components of the line currents can be estimated as a function of fault severity. Experimental r...

This paper describes the problem of voltage sags and swells and its severe impact on sensitive loads and introduces a new solution for doubly fed induction generators to stay connected to the grid during voltage sags. The main idea is to increase the stator voltage to a level that creates the required flux to keep the rotor side converter current below its transient rating. To accomplish this g...

This study investigates the simple vector control of a 3-phase squirrel cage Induction Motor (IM) under open-circuit fault (faulty 3-phase IM). It was shown that it is needed to supply the stator windings with unbalanced currents to remove the oscillating term of the machine electromagnetic torque. The vector control system is based upon Field-Oriented Control (FOC) that has been adapted for th...

Many researches dealt with the problem of induction motors fault detection and diagnosis. The major difficulty is the lack of an accurate model that describes a fault motor. Moreover, experienced engineers are often required to interpret measurement data that are frequently inconclusive. A fuzzy logic approach may help to diagnose induction motor faults. In fact, fuzzy logic is reminiscent of h...