Review of eccentricity fault detection techniques in IMs focusing on DFIG

Abstract

Induction machines are widely used in different applications. Unpredicted breakdown of these machines usually leads to costly downtime and repairs. These expenses can be minimized by using proper condition monitoring techniques. Eccentricity fault is one of the widespread faults causing machine malfunction; its detection could be useful for preventing of harmful consequences. In this paper, different works on eccentricity fault diagnosis of induction machines with different types of supply have been reviewed. Due to extensive use of induction machines in wind turbines (WT) as doubly-fed induction generator (DFIG), in addition to declaration of importance of eccentricity fault diagnosis in DFIG, detection of eccentricity fault in DFIG is also reviewed.

Analysis of Stator Vibration Characteristics in Synchronous Generators Considering Inclined Static Air Gap Eccentricity

“…It is worth noting that when the inclination angle reaches its maximum value, the rotor and the stator have already made contact, which will cause serious damage to the generator. Literature [12] points out that the maximum eccentricity of the generator cannot exceed 10%. Therefore, when the inclination angle of the rotor reaches 10% of the maximum value in each case, the generator must be repaired to avoid further deterioration of the fault.…”

“…When compared to the DAGE, the SAGE causes more eccentricity, which has a greater effect on generators. When the SAGE degree reaches 10% [12], the generator must be repaired to avoid deterioration of the faults.…”

Stator current identification in generator among single and composite faults composed by static air‐gap eccentricity and rotor inter‐turn short circuit

“…After the study, when the degree of SAGE is greater than 10%, will cause the violent vibration of the generator. As the failure worsened, such faults will cause the stator core deformation, winding damage and other accidents [3][4][5]. When the rotor inter-turn short circuit develops to a certain extent, the excitation current will increase significantly, the winding temperature increases, the reactive power decreases, the bearing vibration increases, and even lead to grounding failure, making the rotor magnetized, and the neck and shaft will be burned when severe [6,7].…”