Category Archives: Motor-Design

What is Transient Magnetic Analysis?

Transient Magnetic, is the study of magnetic fields due to time varying currents, typically caused by surges in currents. Similar to Magnetostatic and AC Magnetic, Maxwell’s displacement current that couples the electric and magnetic fields is assumed to be null.In Transient Magnetic analysis, the Gauss’s law for magnetism, i.e. divergence of magnetic flux density is null, and Faraday’s law,, i.e. the induced electromotive force (emf) in any closed circuit is equal to the time rate of change of the magnetic flux through the circuit, are invoked to compute the magnetic field and its related quantities due to permanent magnets and time varying electric currents and voltages. It has many practical applications, including:• Switch on/off modes and failures in power electronic devices
• Saturation in steel cores
• NDT and NDE
• Inductive heating and hardening
• Induction machines
• Levitators
• Motors and generators
• Actuators
• Loud speakers
• Alternators

A Spaceclaim®-embedded Multiphysics Simulation Package


MONTREAL (September 25, 2014) – EMWorks Inc. announces the launch of its multi-physics simulation package SimClaim which is fully embedded in Ansys SpaceClaim®, formerly SpaceClaim, Engineer®.  Based on the powerful finite element method, SimClaim brings the company’s proven simulation technology to the widest base of mechanical, electrical and electromechanical designers seeking to validate and optimize their electrical, thermal, and structural designs all within the SpaceClaim environment. “We are pleased to have partnered with SpaceClaim to bring this all important multi-physics simulation technology to the SpaceClaim user community. The support we received from SpaceClaim over the last couple of years has been instrumental in accomplishing this important milestone for our company” said Dr. Ammar Kouki, Vice-President of EMWorks. He added “Ansys SpaceClaim®, is an extremely powerful 3D direct modeling software package that eliminates CAD worries for designers. Direct modeling is dramatically different from the traditional CAD software because it allows the user to directly access the model without even knowing its history. SimClaim leverages this power to enable designers and CAE specialists to carry out conceptual analysis inside SpaceClaim in record time without needing to be CAD experts. CAD experts on the other hand, will find that the SpaceClaim-SimClaim combination is hard to beat when it comes to design validation through simulation given the speed and the highly efficient workflow that this combination offers.”

Reducing cogging torque


In electric motors, the magnets of the rotor and the slots of the stator interact. This interaction results in the so called the cogging torque. It is also called detent or “no-current” torque. Generally speaking, the cogging torque is undesirable because it causes jerkiness and speed ripple, especially at low speed. It is worth mentioning that a slotless machine is cogging torque free.

There are numerous techniques to reduce the cogging torque. EMS can be instrumental in investigating such technique without the need to build prototypes. For instance, the designer can distort the stator and/or the magnets virtually in SolidWorks or Inventor and run EMS for various distortion angles and study the effect on the torque. Similarly, one can consider various current forms or play on the number of slots. The parameterization feature of EMS makes this task fast and efficient.

Motor Back EMF


Do you know that you can accurately compute your motor Back EMF using SolidWorks, SolidWorks Motion, and EMS right inside SolidWorks?  No need to import or export any file.  Not only can you compute the Back EMF, but also numerous motor parameters such as torque, force, inductance, flux linkage, current, voltage, generated heat, eddy current, flux lines, displacement, speed, acceleration, core loss, joule loss, and more.