In this paper, we propose an electromagnetic-mechanical model based on the finite element and Macro-Element (ME) technique to analyse and study the dynamic characteristics of a Tubular Linear Switched Reluctance Stepping Motor (LSRSM). After the resolution of the non-linear electromagnetic equation governing the behaviour of the different materials of the motor using the nodal-based finite element method, this equation is then coupled to the mechanical equation firstly through the magnetic force computed by Maxwell stress tensor, and secondly by the modified flux distribution due to the moving part. Because of the precision required in the mobile part displacement and the very small air gap of stepping motors, the simulation of the movement is assured by the Macro-Element (ME) technique compared to other movement techniques that present many disadvantages. The validity of the developed model is verified through the comparison of the computed displacement of the LSRSM moving part with those given experimentally [2]. The Results shows satisfactory agreement. The obtained dynamic characteristics, particularly the starting magnetic force, are obtained by considering two values of the supplying currents
The paper proposes a novel approach to assess the integrity of Electrical Insulation Systems (EIS) by evaluating the response of the Transient Voltage Signature Analysis (VSA) to voltage source inverters correlated with changes in the Insulation Capacitance (IC). The involved model structures are derived from the in-situ estimation of high-frequency electromagnetic RLMC lumped network parameters. Different physical phenomena such as inductive and capacitive effects, as well as skin and proximity effects are combined. To account for these phenomena, we use an approach based on equivalent multi-transmission line electric circuits with distributed parameters (R: resistances, L, M: self and mutual inductances, and C: capacitances) which are frequency-dependent. Using the finite element method, firstly the turn-to-ground and turn-to-turn capacitance parameters are performed by solving an electrostatic model with a floating electric potential approach, and secondly, the resistance and self/mutual inductances are computed from the strongly coupled magneto-harmonic and total current density equations, including the conduction and displacement eddy current densities. The sensitivity of the capacitances is measured according to insulation thickness, and the dielectric properties are adopted to test the degradation order scenarios of the EIS and comparing their time and frequency domains of transient voltage waveform behavior with respect to healthy assessed insulation systems.
The present paper introduced a framework for multi-level coupling transient electromagnetic fields (EMF) and mechanical structural dynamics based on the finite element method (FEM). This framework was dedicated to predicting, with better accuracy, the wave magnetic force density for obtaining the mechanical deformation occurring in electromagnetic actuators (EMAs). The first-level EMF transient model coupling is related to the magnetic field equations that are strongly coupled with the electric circuit input voltage equations. This is done by considering the magnetic saturation through the Newton–Raphson (N–R) method. The time-stepping solution of the EMF model resulted in the magnetic force densities being computed from the Lorentz force (LZ) expressions, based on the space–time variation of the induced eddy current. For the second coupling level, the EMF model was sequentially coupled with the mechanical structural deformation equations (MDef) through the local magnetic force density to achieve minimal material dynamic displacement and deformation. The developed multi-physics EMF–MDef time-stepping (FEM) model tools were implemented using the Matlab software.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.