A new analytical technique for analysis and detection of air-gap eccentricity fault in surface-mounted permanent-magnet machines

Rahideh

Int Trans Electr Energ Syst

et al. 2020

Summary This article compares the 2‐D and 0‐D analytical models for the slotless double‐sided inner armature linear permanent magnet synchronous machines (SDSIALPMSMs). The sub‐domain method is implemented to achieve the 2‐D analytical model. In this method, the cross‐section of the motor is divided into eleven sub‐regions and the Maxwell equations are determined for each sub‐region. In the presented 0‐D model, a magnetic equivalent circuit (MEC) is derived to compute the maximum magnetic flux density in the air‐gap. In both approaches, the magnetic flux density is analytically calculated to predict the inductance, induced voltage, flux linkage and electromagnetic forces. Ultimately, the results of both analytical models are validated against those of the 3‐D finite‐element method (FEM) analysis. These results confirm the superiority of the 2‐D analytical model compared with that of the 0‐D in the terms of the accuracy of the magnetic flux density, induced voltage, self and mutual inductances as well as the tangential and normal electromagnetic forces. Also, less computational time of the described 2‐D analytical model is recognized as a merit compared with FEM models.

Section: Introductionmentioning

confidence: 99%

Comparison between 2‐D and 0‐D analytical models for slotless double‐sided inner armature linear permanent magnet synchronous machines

Rahideh

Int Trans Electr Energ Syst

et al. 2020

IET Electric Power Applications

“…However, some deficiencies still exist: (i) The influences of some important design parameters such as winding distribution modes and the number of parallel branches on back‐EMF are ignored. (ii) The effects of the SE ratio on the air gap magnetic field and back‐EMF have been revealed already. However, the effects of SE circumferential angles, which distort the air gap magnetic field and back‐EMF severely, are always neglected. (iii) Most of the eccentric diagnosis methods can only be realised through complicated post‐processing of measurement data in [18–21] or additional devices in [22–24]. As a result, the eccentricity fault cannot be diagnosed quickly or directly or at a low cost.…”

Section: Introductionmentioning

confidence: 99%

“…However, the effects of SE circumferential angles, which distort the air gap magnetic field and back-EMF severely, are always neglected. (iii) Most of the eccentric diagnosis methods can only be realised through complicated post-processing of measurement data in [18][19][20][21] or additional devices in [22][23][24]. As a result, the eccentricity fault cannot be diagnosed quickly or directly or at a low cost.…”

Section: Introductionmentioning

confidence: 99%

“…This method can distinguish the eccentric forms. Hassanzadeh et al also diagnosed different eccentric forms through the frequency characteristics analysis of currents in [23, 24]. Kang et al added additional windings to a motor, and then detected dynamic eccentricity by measuring back‐EMF in the additional windings [25].…”

Section: Introductionmentioning

confidence: 99%

“…8,9,10,11,17,18,19,20,26,27 B w = 2, 3, 4,5,11,12,13,14,20,21,22,23 C w= 5, 6, 7, 8, 14, 15, 16, 17, 23, 24, 25, 26 …”

mentioning

confidence: 99%

See 2 more Smart Citations

Eccentric position diagnosis of static eccentricity fault of external rotor permanent magnet synchronous motor as an in‐wheel motor

Gao

Wang

et al. 2020

An eccentric position diagnosis method of static eccentricity (SE) fault of external rotor permanent magnet synchronous motor (ER‐PMSM) is presented. Firstly, an analytical model of no‐load radial magnetic field of ER‐PMSM is established. Analytical models of no‐load Back‐EMF of both unit motors and the whole motor are carried out and are verified by finite element method (FEM) and experimental measurements. Then, the influences of SE ratio, SE circumferential angle, winding distribution mode and number of parallel branches on no‐load radial magnetic field and no‐load Back‐EMF are analyzed based on these analytical models. The results show that SE does not affect the frequency characteristics of no‐load radial magnetic field, but changes space order characteristics. On one hand, for ER‐PMSM, of which the number of unit motors is equal to 1, SE causes no‐load Back‐EMF distortion. On the other hand, for ER‐PMSM, of which the number of unit motors is greater than 1, SE does not affect no‐load Back‐EMF of the whole motor, but it still leads to no‐load Back‐EMF distortion of unit motors. Therefore, based on total harmonic distortion (THD) of no‐load Back‐EMF of unit motor, a projection method of intersection lines for SE fault diagnosis of ER‐PMSM is proposed finally.

Int Trans Electr Energ Syst

Air‐gap eccentricity fault diagnosis and estimation in induction motors using unscented Kalman filter

Bagheri

Ojaghi

Bagheri

2020

In this paper, a new approach is proposed for eccentricity fault detection in induction motors and estimation of the exact severities of the fault components. By using the Kalman filter estimator, the presented method can estimate degrees of the static, dynamic, and mixed eccentricity faults in the induction motors. The Kalman filter is a robust estimator having high capability in estimating the state variables of a dynamic system. This filter has many practical applications in industrial and nonindustrial systems and can implement continues-/discrete-time dynamic systems varying linearly or nonlinearly. In this paper, due to the nonlinear and continuous nature of the induction motor, the unscented Kalman Bucy filter (UKBF), which is a nonlinear continuous-time filter, is employed. At first, the model of the eccentric induction motor is simulated. Then, by using this model, the measured quantities and the Kalman filter, the eccentricity fault is detected, and the exact severities of the fault components (static, dynamic, and mixed) are estimated for a real motor that has been artificially made to be eccentric.According to the attained results, it is demonstrated that the conducted approach has high capability in estimating the exact severities of the fault components, and it shows efficient performance in all eccentricity states.