Search results for "Electric motor"
showing 8 items of 38 documents
Flux density at the airgap of small DC motors with different permanent-magnet poles
1993
Hydraulic vs. Electric: A Review of Actuation Systems in Offshore Drilling Equipment
2016
This article presents a survey on actuation systems encountered in offshore drilling applications. Specifically, it focuses on giving a comparison of hydraulic and electric drivetrains along with detailed explanations of their advantages and drawbacks. A significant number of industrial case studies is examined in addition to the collection of academic publications, in order to accurately describe the current market situation. Some key directions of research and development required to satisfy increasing demands on powertrains operating offshore are identified. The impact of the literature and application surveys is further strengthened by benchmarking two designs of a full-scale pipe handl…
Electromechanical properties of a disc‐type salient‐pole brushless DC motor with different pole numbers
2003
A brushless, permanent magnet, three‐phase disc‐type salient‐pole DC motor with co‐axial flux in the stator is considered. Electromechanical properties of a basic eight‐pole motor are compared with those for a 16‐pole one of the same volume, in order to contrast the two potential candidates for variable‐speed, low‐cost drives. As a basis of the comparative analysis, 3D FEM magnetic field modelling and circuit analysis considering an electronic commutator are employed. Increasing the number of poles results in unfavourable raising in the switching frequency. The eight‐pole motor construction has been shown in simulations to have higher efficiency and lower power losses than its 16‐pole count…
An Influence of Permanent Magnet Shape on the Torque Ripple of Disc-Type Brushless DC Motors
2006
An analysis of the torque developed by two types of the disc-type permanent magnet (PM), brushless DC motors: slotted torus motor and motor with stator salient poles is presented. The calculations were performed using three-dimensional finite element method (FEM). Two shapes of PMs are analyzed: trapezoidal and rectangular. The results show that application of rectangular shaped PMs provides significant reduction of the torque ripple in both considered motors.
A Hybrid Power Supply with Variable Speed Drive for Automatically Move Irrigation Equipment: Margin of Feasibility
2021
Center pivot irrigation systems are widely used in agriculture. Their water pumping systems are primary energy consumers. The use of photovoltaic power plants and variable speed drives of electric motors can reduce energy costs. The purpose of this study is to determine the feasibility of integrating variable speed drives and photovoltaic modules into water pumping systems. A novel architecture of a pumping system was suggested. Its features are no battery backup and the sale of electricity into the grid.
Performance analysis of photovoltaic powered dc motor — Propeller system
2015
The application of autonomous directly photovoltaic (PV) powered electro-mechanical has received increasing attention for different applications (e.g. PV water pumping, PV powered cooling of arid climate greenhouses, solar vehicles etc). The PV array output is a nonlinear and time-dependent power supply that varies with solar intensity and cell temperature, so the performance characteristics of the directly PV-powered DC motor — propeller system are very different than when powered by a constant DC voltage. The focus of this work is to do performance analysis of directly PV-powered DC motor — propeller system. Through performance evaluation, it has been observed that power transfer matching…
Characterisation of nonoriented electric alloys under nonconventional conditions
1996
The variations of magnetic and loss characteristics of nonoriented cobalt-iron and silicon-iron sheets have been investigated using an Epstein frame. Cobalt-iron alloys have been tested under sinusoidal magnetic flux density with respect to frequency and temperature. Both kinds of alloys have also been investigated with respect to frequency, time constant wavefront and temperature under trapezoidal flux density. The qualitative behaviour is identical under both flux density conditions for all these alloys. These investigations have made it possible to model the variations of iron losses with experimental parameters, except the temperature. These quantitative evolutions differ with alloy and…
A novel improved matlab-based software for the electric and magnetic analysis and design of rotating electrical machines
2015
The aim of this paper is to present a software for the analysis and design of windings of rotating electrical machines, considering both the electric and the magnetic specifications on the machine. The considered machines are induction motors (IM) and PM synchronous motors (PMSM). The software accounts for the case of buried magnets (IPMSM), but with some limits, because the calculations require a much more detailed analysis regarding the magnetic circuit. However, this initial limitation of the software, that will be removed in a later version, does not constitute a major limitation as confirmed by the examples presented in this paper.