Many permanent magnet materials exist today, with the most common being ceramic or ferrite materials, where reasonable performance at very low cost is required. Other common materials include the high energy rare-earth types, plastic or resin bonded ferrite and rare earth variants, and cast alloy types, which are old-fashioned but still important in some areas.

HSMAG has assisted manufacturers of MRI scanner magnets using magneto-static finite element models. The models typically include the large superconducting magnet of the scanner and a soft iron shield which is normally included in the fabric of the building housing the scanner.

Magnetic rotary couplings are often used by pump manufacturers to isolate a motor from the pump components. The isolation of these components might be desirable for one or more reasons. The fluids in the pump may be corrosive, toxic, under pressure, or sensitive to corrosion from motor lubricants or other materials.

Our finite element based techniques can provide invaluable support to designers of rotating machines, including the following tasks:
Flux plots showing leakage, saturation and local flux densities
Quantification of iron loss
Prediction of tooth ripple losses
Cogging torque estimates
Output torque prediction
Radial stiffness prediction
Thermal characteristics
Stress and vibration
Starting performance simulation

HSMAG has assisted in the development of a variety of sensors employing magnetic effects of one sort or another. These include:
Flux gate magnetometers
Salient pole tachogenerators
Rotary and linear inductive pick-offs
Brushless resolvers
Our involvement in projects using these devices ranges from finite element modelling of novel sensors to prove a principle of operation, to advice on the selection and use and occasionally troubleshooting.

We have a wealth of experience in the computer-aided engineering of inductors, transformers and other wound components. Using finite element based tools, we can deliver valuable insight into many performance aspects, with relevance to electrical performance, cost and reliability, including:
Simulation of temperature rises under steady state and transient loading conditions
Accurate prediction of leakage inductances
Plotting of magnetic field distribution and saturation
Prediction of magnetic and thermal stresses

Both electromagnetic and mechanical finite element modelling are powerful tools for designers of electric machines. For high-speed applications, some examples of the areas where we can provide modelling support are:
Rotor containment can losses (caused by modulation of rotor field by stator teeth)
Rotor stress distribution resulting from shrink fitting of containment cans
Rotor stress distribution at maximum speed
Investigation of rotor and shaft vibration modes and critical speeds
Copper losses resulting from leakage fields

We are experienced in classical magnetic circuit design methods, finite element optimisation, and dynamic modelling. We can provide detailed performance predictions based on these techniques, including approximate transfer function representations for those interested in incorporating actuators in closed loop control applications.
For devices which are highly non-linear, for example, conventional d.c. or a.c. solenoids, we can provide a block diagram representation for use in any of the commercial graphical simulation packages such as Matlab/Simulink, or VisSim.

Magnetic linkages are often designed into equipment where it is desirable to separate different sections of the same mechanism. This could be required for a number of reasons, but most commonly it is because two different environments need to be isolated from each other, e.g.
Thermal isolation – mechanical work is transferred through a barrier providing thermal isolation
Chemical isolation – parts of a mechanism are prone to attack from aggressive chemicals or harsh environments
Vibration isolation – Magnetic linkages are excellent for filtering out high-frequency vibration components

We can supply transfer function, block diagram representation, or complete detailed control system designs for motors or actuators. We can also advise on control strategies and power electronics drive configurations for special applications. Examples include position and speed control using brushed or brushless d.c. motors and actuator drivers for fast response applications.

The design of charged-particle beamlines requires close collaboration between beamline physicists, magnet designers and mechanical designers. Best Solution has been a key part of such collaborations for several major ion and electron beamline projects. FE modeling of the magnets allows efficient design of optimized dipole, quadrupole and sextupole magnet structures that produce the required three-dimensional gap field distributions.

Magnetic shield and screen design can be a challenging area. Magnetic shields are made from soft magnetic materials i.e. those with very high permeability. Shield thickness is important, as any saturation in the shield material will make drastically reduce its shielding properties.
Our many years of experience in field problems enables us to work alongside our customers to find cost and performance optimised solutions to their shielding requirements.

The HSMAG design process includes a thorough understanding of the coupled physics of magnetising fixtures using sophisticated finite element modelling methods. Magnetisation transients are observed in 3d models which give a comprehensive insight into magnetic, thermal and stress fields. This insight, coupled with sound practical experience and manufacturing know-how gives us the ability to design and deliver effective tooling for development or production applications.

We were able to provide modelling support on a high field, hybrid magnet project, which used a combination of superconducting, and copper coils, for a magnet with a bore flux density of up to 40 Tesla.

The challenges in the magnet design were extreme, and transient modelling of coupled magnetic-stress and magnetic-thermal-stress fields were required in order to enable parts of the structure to be designed to withstand the enormous forces of a quench.

We can make accurate performance predictions for those designing or developing eddy current brakes. The mechanical design methods we use are largely finite element based and can deliver detailed information on:
Torque vs. speed characteristics
Effect of temperature rise on performance
Effect of material selection on performance
Dynamic response to drive or load transients
In addition, our support can assist in the cost reduction or modification of existing mechanical designs.

For magnet users, how to confirm the grade and magnetic properties are still a long standing issue. Most of users can’t get the value of main magnetic parameters by themselves. In this case, the relative measurement of magnetic properties is the best solution. The relative measurement of magnetic properties includes magnetic field strength, magnetic flux and magnetic moment. For magnetic flux and magnetic moment testing, different specification need different testing coil, and this is the reason why the magnetic field strength is the most popular testing method among the relative measurement.