Torque/current spectral analysis for healthy and eccentricity faulty synchronous reluctance machine using mathematical modeling method

Abstract

SUMMARYIn this research, considering slot opening and distributed winding effects, torque ripple analysis is studied for four separate synchronous reluctance machines (SynRMs) under health and eccentricity fault conditions using a mathematical method. A finite element method (FEM) validated model is produced by mathematical modeling, and numerical method is used for the machine's behavior studying with voltage source supplying. With this aim, the machine's parameters have been computed under health and eccentricity fault conditions, using modified winding function theory (MWFT). A method of dynamic and static eccentricity fault diagnosis is proposed, which uses machine vibration analysis, and the results suggest that the eccentricity fault does not have any significant effect on the machine's currents. Moreover, unbalance magnetic pull (UMP) is computed under eccentricity fault conditions and mechanical un-stability is shown. Mathematical base model and voltage source machine supply and also presenting a discrete machine modeling method are the main advantages of this paper compared with other similar works that are usually FEM-based studies or have been based on current source power supply. The research is applicable to healthy and faulty machine behavior, and the methodical modeling is obviously applicable to other machines.

An enhanced analytical technique based on winding function theory for analysis of induction motors

“…WFT has been introduced as the main tool for inductance calculation in many papers 3,[18][19][20][22][23][24][26][27][28] by using Equation (1) as…”

“…The basic assumption of WFT is to consider the iron parts as ideal core. 3,4,18,19 In this paper, a virtual winding function (N sat,x (α)) is presented, which can consider the mmf drop in iron parts due to the excitation of phase x. The nonlinear MEC model of WRIM 29 is used to calculate the scalar magnetic potential in different parts of stator and rotor under the excitation of phase x only.…”

“…Using the analytical techniques, the users can get a good knowledge about the motor performance in a short time. Nowadays, the analytical techniques are really acted as the semi-analytical technique, such as winding function theory (WFT), 3,4 magnetic equivalent circuit (MEC), 5,6 sub-domain (SD) model, 7,8 conformal mapping (CM) method, [9][10][11] and field reconstruction method (FRM). 12,13 The MEC acts based on the reluctance network analysis of the studied machine.…”

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

“…The total air-gap field, B tr (r, θ, t), is equal to the sum of the no-load field obtained by (10) and the armature reaction field by (22) as follows:…”

“…Detection of the eccentricity fault in induction machines and synchronous generators has been the subject of many papers. New machines and drives need more precise, quick, and easy fault diagnosis methods, so mechanical faults such as eccentricity fault and magnetic faults such as demagnetization fault in permanent‐magnet (PM) machines have been widely studied in order to find more accurate and simpler diagnosis methods.…”