Current measuring technology topics - Join the conversation!

Running smoothy? Position-dependent magnetic field measurement for the optimum electric motor

2020-02-21 | Know-how | Reilly, Karin
Important for every electric motor: The alignment of the magnetic field to the mechanical
The solution: The MarForm MMQ 200 form tester with 3D Hall sensor from Senis

The operating principle of an electric motor is based on magnets and their properties. Without them it would not be possible to convert electrical energy into motion. In order to optimize an electric motor in terms of efficiency and noise level, the magnets used must meet the most precise specifications and be precisely mounted. This is because design errors quickly lead to a reduction in performance or increased noise.

The electric motor in quality check

While checking the individual magnets is already common practice, checks of the electric motor system as a whole, i.e. in the assembled state, represent a new challenge for vehicle manufacturers. Important factors include compliance with the geometric specifications of all bearing points and a uniformly strong three-dimensional magnetic field in space – prerequisites that have not been met by the combustion engine to date.

In order to test these requirements, one thing above all is decisive: the alignment of the magnetic field with the mechanical axis of rotation of the motor. For this purpose, in addition to measuring the magnetic field, the position of the components must also be determined –only the two pieces of information together can lead to a qualified statement.

Form metrology with magnetic field measurement

To meet this new challenge, metrology specialist Mahr and the Swiss company Senis AG have developed a solution that combines magnetic field information and position determination. For this purpose, Mahr's MarForm MMQ 200 formtester was combined with a SENIS F3A-KM 3D Hall sensor.

On the measuring machine equipped in this way, the installation position of the rotor is simulated, which enables a meaningful analysis of the running characteristics. With the joint solution from Senis and Mahr, it is possible to determine, for example, the exact magnetic pole width and magnetic orientation as well as concentricity or eccentricity of the magnetic field.


Three-dimensional representation of the magnetic field


Amplitude and phase position of the magnetic field vectors


Wanted: Partners for R&D

The new solution for designing electric motors is already available under the name "MarForm MMQ 200 with 3D magnetic field measurement". In order to identify additional fields of application, Mahr is now looking for companies from the fields of motor development or automotive engineering for joint R&D projects.


Would you like to know how you can optimize your electric motor with this new solution? Then please contact:

Kai Sander
Global Product Manager MarForm & MarGear at Mahr | +49 (551) 7073-99343 

How did you like this article?
Thank you for your feedback.
Uvést komentář/zhodnocení