Category Archives: Electromechanical

Embedded Electro-mechanical/ Electro-magnetic (EM) simulation inside Autodesk Inventor


by Arvind Krishnan, Director of Product Management, EMWorks

What is EM simulation?

Electro-magnetic or EM simulation is the use of computational techniques to determine the electric and magnetic fields in an electric machine or device. EM simulation can give valuable insight to an engineer about his designs. She can obtain engineering parameters like inductance, flux linkage, impedance, Back EMF, Induced voltage, Capacitance, Forces and Torques etc. So engineers who design electrical devices like motors, generators, linear transducers, inductors, actuators, transformers, voice coils, sensors, resistors, insulators, induction heaters etc can benefit largely from EM simulation. Without EM simulation, one would have to resort to costly prototype testing to validate their designs leaving little or no room to optimize and improve the products.

Benefits of EM simulation

EM simulation fits very well into the design process. Companies who use EM simulation are able to create high quality optimized products which make them hypercompetitive in todays market. The rise in popularity of simulation tools have ensured that companies all around the world from industrialized nations of the west to the developing nations of the east have a level playing field. What is more important is that the seamless integration of EM simulation into the product development process have accelerated this trend. Now an engineer can quickly put his concepts and inventions to life my modeling them in 3D CAD packages like Autodesk Inventor. CAD embedded EM simulation packages like EMS for Autodesk Inventor enables them to validate, improve and optimize their design quickly without ever entering a testing laboratory or engaging in a prototype. Further more, EM simulation can be coupled to mechanical and thermal simulations to accurately predict the thermal and mechanical performance of electrical devices. Once the design is accepted, 3D printers bring life to these digital products which can then be tested before they are sent for mass manufacturing. This 3D digital engineering product development process has revolutionized the electrical machines and devices industry. Figure 1 shows a typical product development workflow using Autodesk Inventor and EMS for Inventor.


Figure 1 – The product development workflow inside Autodesk Inventor

Benefits of integration inside Autodesk Inventor

Autodesk Inventor is a very popular 3D CAD platform for engineers in the field of electrical machines and devices. EMS for Autodesk Inventor enables engineers to incorporate EM simulation into their product development process. Integration inside Autodesk Inventor brings in the following advantages –

  1. Direct use of 3D CAD model for simulation. No need to export CAD geometry for simulation purpose thereby maintaining the integrity of the design.
  2. Enable simulation based product development where simulation feeds into the 3D design allowing engineers to make drastic changes to their initial design concept. All of these are possible without ever leaving Autodesk Inventor platform.
  3. The learning curve for engineers to learn and use simulation is shortened because they don’t have to learn a new program and a new interface. They can work inside their familiar Autodesk Inventor interface to perform their EM simulations.

Application areas

EM simulation has many applications areas ranging from small electrical machines to large transformers. These devices can use DC, AC or other kinds of excitation. The applications of electromagnetics are so vast that it will be a great injustice to categorize them as I have attempted here for the sake of brevity. I admit that there are many devices and applications that overlap these categories.

  1. Rotary and linear actuators, Motors and Generators
  2. Transformers, Inductors
  3. Insulators, high power switches, bus bar networks, Induction heaters
  4. Sensors, motion controllers and measurement devices
  5. Permanent magnet based devices, magnet arrays, magnetic levitation

EMS for Inventor can calculate the magnetic field inside a motor and also the cogging torque

Figure 2 – EMS for Inventor can calculate the magnetic field inside a motor and also the cogging torque

EMS for Inventor can help visualize the losses in the core of a transformer

Figure 3 – EMS for Inventor can help visualize the losses in the core of a transformer


EMS for Autodesk Inventor is a 3D field simulation software that is embedded inside Autodesk Inventor. It can perform both electric and magnetic simulation with AC, DC and transient excitations. EMS has powerful Multiphysics capability to do coupled EM, mechanical and thermal simulation. EMS customers use the product to design solenoids, motors, transformers, magnet arrays, high voltage insulators, electric generators, speed sensors, induction heaters, bio-medical actuators and magnetizers. Autodesk Inventor customers can download a full trial version of EMS in the Autodesk App store. For more information on EMS, visit

Magnetic bearings



Bearings are devices which constrains the relative motion of a moving (rotating or translating) part. They also aid in reducing friction. When we think of a bearing we often think of only a mechanical bearing (see image) as it is the most commonly used type of bearing.

Bearings have numerous applications in the field of machine design, automotive, transportation, oil & gas, medical apparatus etc. They are ubiquitous in any device that has motion. In this brief note, I will discuss a bit about a different kind of bearing, Magnetic bearing and highlight its advantages when compared to a mechanical one.

Limitations of mechanical bearings

Mechanical bearings have limited life due to wear and tear and they require lubrication. In many high speed applications they also may need special type of cooling. Nevertheless it is an exhaustible component that needs to be replaced several times during the life of its parent device.

Magnetic bearing

A magnetic bearing facilitates the same functions of a mechanical bearing by employing a magnetic array of permanent magnets. In short there are 2 sets of concentric magnetic arrays which are held in place by the magnetic forces. Since there is no contact there is no wear and tear and technically the magnetic bearing has a very long life.  In addition it can handle very high speeds and large loads with zero friction. This makes a magnetic bearing an excellent choice for machine design, marine, automotive, aerospace and medical devices industry. Recently, there has been a surge in the use of magnetic bearings across various industries. Below is an image of an axial magnetic bearing designed in SoldiWorks. In this design the outer bearing is stationary and the inner bearing is connected to a shaft and is spinning. The weight of the shaft is supported by the magnetic force exerted on the inner bearing.

A magnetic bearing design simulated using EMS for SolidWorks

EMS for SolidWorks helps bearing designers to size their magnetic arrays to support various designs of the shaft (basically different weights). This way the bearing can ensure optimum performance. Another advantage of a magnetic bearing is that it can support offset of the inner cylindrical array wrt to the stationary outer cylinder.


EMS software can predict accurately the forces acting on the inner bearing for various offset positions.

The magnetic arrangement is assembled according to the figure given below. The N-S directions of each magnet is indicated by the black arrows. This type of arrangement can be easily created in EMS and the magnetic flux distribution and the axial force acting on the inner array can be visualized and computed respectively.



Variation of axial force acting on the inner magnet array with the offset is shown below and is automatically computed by EMS. Note that as the offset increases, so does the axial force but after a point the force reduces. Beyond an offset of 18 mm, the force reverses direction and pulls back the inner array. Using these values of axial force, we can compute the axial magnetic stiffness coefficient


EMS for SolidWorks

EMS for SolidWorks is the first and only completely embedded Gold Certified software for SolidWorks which helps SolidWorks users study their magnetic, electric and electromagnetic designs seamlessly. It can utilize the geometry created using SolidWorks directly for simulation. Its user interface emulates the SolidWorks and hence there is no learning curve associated with the EMS software for SolidWorks users. Please click here to try out EMS for SolidWorks and see how it helps you design better products. For more information visit


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

Locking your study in EMS and HFWorks


To protect your work from accidental changes, we recommend that use the Study Locking feature in both EMS and HFWorks. A locked study may be viewed but cannot be edited or changed. Of course, you can always unlock the study if you need to make changes.  To lock your study simply right-click on the study name and select Lock.  To unlock select Unlock.


Simplicity Facilitates Magnetic Component Design


Latest Generation Of 3D Electromagnetic Finite Element Analysis Software With Breakthrough Simplicity Facilitates Magnetic Component Design

by Peter Markowski, Envelope Power, Ansonia, Conn.

Finite element analysis (FEA) software is a great tool for simulating electromagnetic fields in chokes and transformers, allowing accurate computation of the spatial distribution of the current, flux density, associated losses and resulting temperature rise as well as the impact of the magnetic component on the efficiency of the converter. By manipulating dimensions and geometrical arrangements we can arrive at the most compact, efficient and lowest-cost structure. Unfortunately, 3D FEA software gained the …

Read the full story…

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.”

Electromechanical devices in EMS?


Electromechanical, electromagnetic, and power electronics devices can readily be studied using EMS. Electromagnetic behaviour could also be investigated with EMS. Below is sample list of devices and applications classified by areas:

• Motors and generators
• Linear and rotational actuators
• Relays
• Magnetic recording heads
• Magnetic levitation
• Solenoids
• Loud speakers
• Electromagnetic Brakes and Clutches
• Alternators
• Magnetic bearings

• Coils
• Permanent magnets
• Sensors
• High power
• High voltage
• PCBs
• MRI Magnets
• Induction heating
• Bushings
• Switchgear
• Cables

Power electronics
• Transformers
• Inverters
• Converters
• Bus bars
• Inductors

Electromagnetic behavior
• Insulation studies
• Electrostatic discharge
• Electromagnetic shielding
• Electromagnetic exposure