Magnetic circuit

About: Magnetic circuit is a research topic. Over the lifetime, 15707 publications have been published within this topic receiving 118099 citations.

Nuclear magnetic resonance apparatus including permanent magnet configuration

Abstract: An apparatus for nuclear magnetic resonance scanning and imaging which employs a primary magnetic field, an rf field, and a detector for detecting a nuclear magnetic resonance signal, the primary magnetic field being produced by an assembly of relatively low energy flux magnetic material combined with an assembly of relatively high energy flux magnetic material. The magnetic flux of the relatively low energy flux magnetic material is concentrated in a magnetic flux conductor means which is in turn combined with the magnetic flux of the relatively high energy flux magnetic material and is concentrated at a pole piece.

Transformer with parallel magnetic circuits of unequal mean lengths and loss characteristics

Abstract: An electrical transformer having an electrical winding and a magnetic core having two parallel magnetic circuits having unequal mean lengths. The shorter of the parallel magnetic circuits is constructed of a magnetic material which exhibits a lower loss characteristic than the magnetic material used in the longer of the parallel magnetic circuits, at like levels of induction.

Parameter Design of IPMSM With Concentrated Winding Considering Partial Magnetic Saturation

Abstract: The interior permanent magnet synchronous motor (IPMSM) is usually applied to the traction motor in the hybrid electric vehicle and the electric vehicle due to its high-power density and wide speed range. In this paper, the IPMSM with concentrated winding for a 110 cc electric motorcycle is introduced. Its design was improved for high efficiency and a wide speed operation range. The output characteristics were also analyzed according to the partial magnetic saturation of the shoe and web in many variables. Because partial magnetic saturation affects the harmonics and the eddy current loss of the permanent magnet, it was confirmed that the output characteristics of the motor significantly changed. As a result, the new shape and the design parameters for which the partial magnetic saturation was considered were obtained. Higher level efficiency and a wider operating range than with the base model were confirmed.

Effect of end core flux on the performance of the switched reluctance motor

Abstract: The aim of the paper is to bridge the gap between two-dimensional and three-dimensional finite-element modelling of the switched reluctance motor. The flux linkage/current diagram and static torque profile of a four phase 8/6 machine are computed with the aid of two-dimensional and three-dimensional models. Comparison of the predicted values with measurements on the motor demonstrates the superiority of three-dimensional modelling. Three-dimensional effects in the switched reluctance motor are examined and a suitable procedure for estimating the end-core flux at a range of rotor positions and excitations is proposed. The sensitivity of the end-core flux value to magnetic circuit parameters such as applied MMF, magnetic saturation and path reluctance is presented.

A Coincident-Current Magnetic Memory Cell for the Storage of Digital Information

Abstract: A small, ring-shaped, ferromagnetic core with properly "rectangular" B-H characteristics may be operated so that its flux polarity reverses only when the correct combination of two or three magnetizing windings are coincidentally excited Such cores may then be used as memory devices and assembled into a two-or three-dimensional memory system with storage-cell selection at the intersection of two or three space co-ordinates Only a core which retains a large percentage of remanent flux of the proper polarity, in spite of repeated "nonselecting" disturbances, can be used as a coincident-current magnetic memory unit Repetitive pulse-pattern testing designed to obtain quantitative data on the operation of such units, in the form of defined "information-retention ratios" and "signal ratios," indicates that only a few core materials are satisfactory