Characterising Magnets with Open-Loop and Closed-Loop Systems: Where do Both Worlds Meet?
by Luc Van Bockstal of Metis Instruments & Equipment n.v.

Magnet characterisation is industrially done with a Helmholtz coil or a hysteresisgraph with pole shoes. The possibilities were extended with pulsed field magnetometers such as the HyMPulse. The pulsed field magnetometer and the Helmholtz coil are measurement techniques where the sample is in an open magnetic circuit, whereas the hysteresisgraph puts it in a closed loop. Although the IEC TR 62331 report states that the permagraph and HyMPulse yield the same basic results, a very close look reveals slight differences. An overview of the advantages and differences will be given, including the bridges to make actual comparisons between open-loop and closed-loop systems.

Accurate 3-axis Measurement of Inhomogeneous Magnetic Fields
by Dragana Popovic Renella of Senis AG

Hall effect based Teslameters/Gaussmeters and Magnetic Field Mappers measure DC and AC magnetic flux densities. For accurate measurement, a 3-axis Hall probe is applied with small magnetic field sensitive volume (MFSV) of 100μm x 10μm x 100μm, with vertical and horizontal Hall elements integrated on a single chip. The orthogonality error of the 3-axis Hall probe is reduced to smaller than 0.1°. This presentation will explain why the above features are important for some applications in industry and modern science for accurate measurement of inhomogeneous magnetic fields and how to achieve them.

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New Measurement Technologies for Soft and Hard Magnetic Materials for Electric Drives and Automotive Applications
by Lukasz Mierczak of Brockhaus Messtechnik GmbH & Co

Magnetisation Process of Permanent Magnet Target for Magnetic Sensors Application
by Stefano Tizianel of Laboratorio Elettrofisico

In a wide range of applications, hall sensors read magnetic field from permanent magnet supports. These PM supports are built and assembled with industrial production lines. One of the most delicate process is the MAGNETISATION. One may think that charging a capacitor bench at 1/2CV^2, and abruptly discharging it into a solenoid obtaining magnetic energy 1/LI^2, is a boring task, not worthy dealing with from a scientific point of view. Indeed the matter conceals a big source of application performance improvements and exciting theoretical understanding. Design and construction of magnetizing fixtures starts from prototypes, based on analytical and FEM calculations, and fast moves to robust construction for high duty cycle industrial production devices. The very first step is defining what type of support we want to magnetize, such as what kind of PM material, what orientation, how many pole pairs, how many traces on the same support, how regular are the polarities distribution. Then the accuracy of the magnetic footprint must be defined, such as saturation level, pole single or total pitch errors accepted. A more practical task is to understand what is around the support, such as metallic magnetic parts, bearings, field PM of electric motor inductors, over-moulding, what productivity is required in terms of magnetizations per hour. The design procedure starts from deciding which kind of magnetizing fixture is required, in a wide range of typologies, direct or indirect fixtures, iron or iron-less cored, solenoids or multi-polar fixtures....; next steps are calculation and simulations, design, construction and test. The aims of this work are to introduce the argument of the industrial magnetization and to focus on the calculation and design of those fixtures, in order to show how the application designer could take profit being aware of potentiality and problems related to the magnetisation.

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Airborne Instruments part of SkyTEM Surveys
by Kristoffer Mohr of Airborne Instruments

Presentation of the SkyTEM system. The system is an airborne geophysical survey system towed by a helicopter HTEM. Based on Transient ElectroMagnetic method. Briefly cover the history of the company. The method, the specification of the system and capabilities.

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The Billund special: LEGO® Based Magnetic Field Mapper
by Philip Keller of Metrolab Technology SA

Several commercial systems for magnetic field mapping are now on the market. The basic elements of any such system are a calibrated Hall sensor – or sensor array – and a mechanical positioning jig. We will present a novel field mapper where the mechanical positioning is handled by... LEGO® bricks! The multi-sensor approach can handle situations that others cannot, such as time-varying fields and large magnet assemblies. In addition, the modularity of the system provides a low cost of entry. Last but not least: it’s fun!

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Science and Technology Aspects of the SWARM Mission
by José M.G. Merayo of Technical University of Denmark, National Space Institute

Quality Control of Permanent Magnets
by Hossein Alimadadi of DTI

Challenges in Magnetic Measurement
by Graeme Finch of NPL

Standardised measurements are invaluable in providing traceable and comparable measurements around the world. However, they do not always demonstrate how magnetic properties may change depending on the conditions in which materials are used in operation. NPL are developing methods to adapt standard magnetic measurement techniques and practices to provide solutions to real-world challenges. Measurement of permanent magnets and soft magnetic materials at a range of temperatures, stresses and for different sample geometries allows an understanding of material performance under operational conditions. Knowledge of how materials age will also give a more accurate prediction of performance over a period of time, with enormous benefit for the automotive and aerospace industries. In addition to this, modelling of magnetic fields can provide insight into EMC and human exposure to EM fields in the presence of inductive power transfer systems, which are already being used for charging of hybrid and electric vehicles. Measurement techniques have also been modified to provide non-destructive testing solutions characterising corrosion and mechanical defects, as well as through-plate measurement of wall thickness for the energy sector. To allow material properties to be characterised under these conditions, the sensor and instrumentation used also needs to be developed and validated.

Siemens Magnet Quality Control
by Hans-Jørgen Thougaard of Siemens Gamesa

Magnet Measurements in Helmholtz coils
by Flemming Buus Bendixen of Sintex A/S

Fluxmeters with helmholtz coils are fast and easy to use for measurements of magnetic moment in permanent magnets. Accuracy is also very good if the sample size and placement is with certain limits. Finding the magnetic remanence from the magnetic moment require accurate volume, but also accurate geometrical knowledge used for calculating the average load line. The load line is calculated from finite elemente and compared to two different analytical models, in two cases where the geometry is cuboid and cylindrical. The load line is found within a few percent accuracy in the best model.

Accuracy Impacts of Injection Molded Magnets on Positional Sensor Applications
by Thomas Schliesch of Max Baermann GmbH

The positional accuracy of magnetic sensor systems with injection molded magnets depends on different parameters. In the presentation the different sorts of injection molded magnets for the most common magnetic position sensors will be explained as well as the basic physical principles of their interaction. By different examples there will be shown how to improve external field components of magnets, so that lower positional errors result at the sensor output. Those improvements can be reached often by relatively simple shape enhancements. In other cases a meticulous design of the magnetizing facilities is needed to provide sensor signals with low deviations from an ideal behavior. Beside experimental results, related design methods on FEM basis will be explained for the magnetization process of the magnet as well as for the analysis of the magnet-sensor interaction itself. Finally the impact of process parameters of injection molding will be presented.

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A Fibre-Coupled Diamond Magnetometer
by Gavin Morley of University of Warwick

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Quantum Well Hall Effect (QWHE) Sensors for Non-Destructive Evaluation Applications
by James Watson of University of Manchester

Provides an overview of the work done by Prof. Missous and his research team at University of Manchester into some of the uses of QWHE sensors and recent advances made. Includes a more detailed look at the advances made in non-destructive evaluation applications of using QWHE sensors.

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Magnets and Sensors for Fun - Applied in Advanced LEGO Toy Products
by Henning Kirk & Henning Mikkelsen of LEGO

Next Generation Graphene for Magnetic Sensing Applications
by Ivor Guiney of Paragraf Ltd

This talk will focus on Paragraf’s solution to graphene manufacture, along with prospective applications for graphene in magnetics, and finally focusing on the magnetic devices that Paragraf is currently pursuing and developing.

VSM and SQUID Based Magnetic Measurement Systems
by Tobias Adler of LOT-QuantumDesign

The theory of operation for VSM and SQUID based magnetometer will be reviewed based on current examples of low temperature high magnetic field magnetic measurement platforms by Quantum Design.

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Magnet Design Methods for Magnetic Equipment and Sensors
by Andrea Roberto Insinga of DTU

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Hospital use of MRI-systems
by Michael Væggemose of Aarhus University Hospital

"Hospital use of MRI" is a wide title and given that I only have 25min I have chosen to focus on the magnet in the MRI scanner. How do we control the field and finally how do we produce images with the scanner. I will naturally show a few MR images in the end.

Overview of Magcam’s Magnetic Field Camera Technology
by Koen Vervaeke of Magcam NV

An overview of Magcam’s magnetic field camera technology with application examples, focused on PM rotors and rotary encoder magnets. The magnetic field camera technology includes the MiniCube3D magnetic field camera as the core magnetic imaging sensor. The measurement data are analyzed using Magcam’s powerful MagScope software. For measuring small magnets the MiniCube3D is used in combination with the MiniTable to accurately and repeatably position magnets, without any moving parts. For measuring larger flat magnets and assemblies we use the Portal or Combi scanner, a motorized cartesian scan stage on which the MiniCube3D sensor is mounted, optionally together with a high accuracy laser sensor for dimensional an topography measurements. For measuring PM rotors, the Combi Scanner can be expanded with a rotary table. Alternatively the dedicated Rotor Scanner can be used. Detailed examples are presented of the measurement and data analysis of a PM rotor and a rotary encoder magnet.