Search results for "Winding"
showing 10 items of 37 documents
Current signature based fault diagnosis of field-oriented and direct torque-controlled induction motor drives
2017
In this article, the operation of three-phase squirrel-cage induction motors is analysed under faulty conditions in closed loop with state-of-the-art controllers, namely, the field-oriented control...
Mechanical testing and numerical modelling of pull-wound carbon-epoxy spinnaker poles
2002
The paper deals with experimental testing and numerical simulation of the mechanical behaviour of multi-layer cylindrical coupons, of two different diameters, made in carbon-epoxy composite. The aim of the study is to provide a simple and effective numerical model that can be used as a design tool for structural elements having analogous geometrical and manufacturing characteristics. The numerical analysis, performed in the elastic regime with a standard finite element (FE) code, was strongly correlated with the laboratory determination of fibre-volume fractions and of some elastic parameters of the material system. Other parameters, like the shear modulus values G, were in fact appropriate…
Thermal and rheological characterisation of a thermoset matrix for filament winding modelling
2004
Rheo-kinetic behaviour of an epoxy resin, coupled with an aliphatic polyamines hardener, used in fibre reinforced plastics, was analysed comparing experimental data to theoretical models. Then the modelling of technological filament winding process for thermoset matrix composites, developed through a numerical code realized with MATLAB, is reported. The model includes winding and curing phase decoupling the manufacturing process into sub-models. Four sub-models are used: fibre motion, thermal, kinetic and rheological model. Considerable differences are obtained in process condition, using several thermal treatments. The numerical modelling helps to detect the process conditions to optimise…
Improving High Frequency Transformers behavior for DC-DC Converter Used in Electric Vehicles
2018
The paper presents a design procedure for high frequency transformer windings adopted in the DC-DC converter used in electric vehicles. The output of the design procedure is the integration of a 3D printed plastic case in the transformer windings, with the aim to maximize the output power. The proposal design procedure is entirely based on a finite element analysis approach and on a differential evolution algorithm used for the solution of the optimization problem.
Evaluation of the power quality from a seawave power farm for different interconnection schemes
2007
In this paper we present an approach to the interconnection of a seawave power farm to the grid The generator type used in the farm is a Permanent Magnet (PM) linear generator driven from the seawaves that generates, therefore, highly distorted emfs. We propose and compare two possible ways to interconnect the farm to the grid. One is based on an approach where for each generator there is a conversion subsystem that permits the direct connection of each generator to the a.c. network, the other one is based on an ac.-d.c. converter that is connected to the generator, the converter is connected to a dc link that can receive the power from every unit and that can supply a dc-ac converter direc…
Assisted software design of a wide variety of windings in rotating electrical machinery
2014
In this paper a software developed by the Authors for winding design is presented. In particular, this software can be used as a valid aid in design and analysis for a wide variety of windings with generic number of phases, pole pairs, slot number, etc.. The calculation of winding factors and the evaluation of their harmonic distribution is also accomplished. The software is implemented in MATLAB® environment. By means of some examples, covering the most relevant winding types, the capabilities of this software will be shown. Particularly, integer and fractional slot, single and double layer winding, concentrated windings, imbrication, belt widening and belt shifting techniques can be treat…
Modeling of ITER TF cooling system through 2D thermal analyses and enthalpy balance
2017
Abstract The winding pack of the ITER Toroidal Field (TF) coils is composed of 134 turns of Nb3Sn Cable in Conduit Conductor (CICCs) wound in 7 double pancakes and cooled by supercritical helium (He) at cryogenic temperature. The cooling of the Stainless Steel (SS) case supporting the winding pack is guaranteed by He circulation in 74 parallel channels. A 2D approach to compute the temperature distribution in the ITER TF winding pack is here proposed. The TF is divided in 32 poloidal segments, for each segment the corresponding 2D model is built and a thermal analysis is performed applying the corresponding nuclear heating computed with MCNP code considering the latest design updates, such …
Design of a Permanent Magnet Synchronous Generator using Interactive Multiobjective Optimization
2017
We consider an analytical model of a permanent magnet synchronous generator and formulate a mixed-integer constrained multiobjective optimization problem with six objective functions. We demonstrate the usefulness of solving such a problem by applying an interactive multiobjective optimization method called NIMBUS. In the NIMBUS method, a decision is iteratively involved in the optimization process and directs the solution process in order to find her/his most preferred Pareto optimal solution for the problem. We also employ a commonly used noninteractive evolutionary multiobjective optimization method NSGA-II to generate a set of solutions that approximates the Pareto set and demonstrate t…
Quantized adiabatic quantum pumping due to interference
2002
Recent theoretical calculations, demonstrating that quantized charge transfer due to adiabatically modulated potentials in mesoscopic devices can result purely from the interference of the electron wave functions (without invoking electron-electron interactions) are reviewed: (1) A new formula is derived for the pumped charge Q (per period); It reproduces the Brouwer formula without a bias, and also yields the effect of the modulating potential on the Landauer formula in the presence of a bias. (2) For a turnstile geometry, with time-dependent gate voltages V_L(t) and V_R(t), the magnitude and sign of Q are determined by the relative position and orientation of the closed contour traversed …
Topological Defects in Nanostructures—Chiral Domain Walls and Skyrmions
2016
In this chapter, spin structures with particular topologies in confined geometries are presented. Domain walls in nanowires exhibit a spin structure that depends on the material and geometry while in discs Skyrmions can be stabilized by different competing interactions. The topologies of these spin structures can be characterized by a Skyrmion or Winding number that governs the dynamics and stability.