JMAG Newsletter January,2011Introducing JMAG-Designer Ver. 10.4
Introducing JMAG-Designer Ver. 10.4
- Simple to be Precise -
JMAG-Designer Ver. 10.4 was released December 7, 2010. The latest version has evolved by combining the know-how of the most experienced engineers to provide a comprehensive analysis software which is easy to use for anyone experienced or inexperienced in computer aided engineering (CAE).
This article introduces the latest features that have been implemented into JMAG-Designer 10.4 along side primary examples of how to use the new modeling, analysis, and linking features.
Let's start by taking a look at the new modeling features that are available.
Simplifying geometry appropriate to satisfy the objective of an analysis while reducing the scale of the model greatly illustrates the know-how required for modeling. However, the new defeaturing capabilities implemented into JMAG-Designer Ver. 10.4 allow users to simplify the geometry of models by automatically removing fillets, chamfers, and holes when generating mesh.
Almost all of the parts utilized for electromechanical machines take advantage of fillets and chamfers (features) to round corners and prevent injury to users as well as the chipping of the parts themselves. These types of features cause the mesh to become dense, increasing the number of elements when the mesh is generated, because of the extremely small area these features make up compared to the entire model. Furthermore, they have very little affect on the analysis results. These types of unnecessary features need to be removed from the geometry to limit the number of elements, and in turn, limit the calculation time and memory that is required.
However, CAD software has been the only way to edit the geometry of models. Therefore, editing models also required an a vast amount of time and effort, especially for models without any feature information, because the geometry had to be re-modeled from scratch.
This cumbersome defeaturing process has now been automated in JMAG-Designer Ver.10.4 Defeaturing can be specified as an option for generating mesh. Fillets and holes to remove can be filtered by simply setting the their dimensions. CAD geometry no longer needs to be re-modeled to reduce the number of elements because the geometry of the mesh model can be simplified without ever touching the CAD model itself.
*Defeaturing requires a separate license.
Deleting fillets and unnecessary holes using defeaturing
The mesh morphing feature implemented into JMAG-Designer Ver. 10.4 allows the geometry of mesh models to be directly manipulated. Small changes to geometry can be emphasized and evaluated in the analysis results using the mesh morphing feature because, the differences in the mesh caused by these small geometrical modifications is minimal which limits mesh noise in the results. In addition, there is no need to return to the CAD system to edit geometry because morphing can be specified right in the graphical user interface of JMAG-Designer, just like defeaturing. The topology of mesh is maintained after the geometry is modified by moving the position of nodes in the mesh to change the geometry. The mesh quality does not deteriorate because the position of the nodes inside of the entire part to modify are automatically optimized as the specified area is deformed. Modifications to the geometry can be finely tuned via settings to constrain the geometry and connections, rather than just simply displacing edges or faces.
The mesh morphing feature is effective for tolerance analysis. A tolerance analysis requires analyses for multiple models that have differing geometry to examine the effects of the dimensional or geometrical tolerance of products after assembly. The mesh models used for the analyses differ, even if the geometry is almost the same, because the mesh is generated for each model. Therefore, clearly determining whether the differences in the results are caused by the changes in geometry or the differing mesh becomes difficult. Anyone who has performed tolerance analyses has experience manually generating mesh so that the mesh topology for each model is the same reducing the effects of differing mesh. Mesh models that maintain the mesh topology without the time and hassle of editing the model geometry and re-generating mesh can be done with the mesh morphing feature.
Changing the width of teeth using the mesh morphing feature
Rapidly Calculate the Magnet Loss of Rotating Machines
The speed of the magnetic field analysis solver continually increases. High speed calculation for eddy current analyses of magnets in IPM and SPM motors has been implemented into JMAG-Designer Ver. 10.4.
Loss distribution caused by eddy currents produced in magnets
3D analyses have to be performed to account for the three dimensional phenomena of eddy currents flowing in magnets. Furthermore, a large number of steps need to be evaluated to shorten the time interval to avoid problems of time harmonic related components of PWM, etc. A high speed 3D analysis can be performed by referring to the magnetic flux distribution of the gap obtained in advance using 2D analysis. Eddy current loss calculations that once took 8 hours using conventional methods can now be performed in 12 minutes, including the time required to run a first stage analysis (varies by analysis model).
The high-speed loss calculation for rotation machines is suited for anyone who has been forced to avoid these types of analyses due to time constraints, even though the results could be invaluable.
Analysis Accounting for Permeability Distribution
Features have also been implemented to provide even more precise analyses. Analyses can now be preformed by fixing, or freezing the magnetic characteristics of materials in JMAG-Designer 10.4 The two main applications for this feature are, evaluating the magnetic flux density distribution and flux lines by isolating each of their magnetomotive forces, and isolating and evaluate the magnetic flux distribution and flux lines of the magnet and the load current separately in load analyses of motors using permanent magnets. The magnetic flux for motors using permanent magnets can be broadly divided into the flux produced by the permanent magnets and the flux produced by the load current. The magnetic flux that is obtained separately and added together is larger than the results of an analysis evaluating both the magnet and load current because the magnetic saturation is not taken into account. However, JMAG-Designer Ver. 10.4 allows the operating points of an analysis evaluating both magnets and load current to be obtained in advance to evaluate the magnetic flux density distribution and flux lines separately utilizing the frozen permeability in an analysis.
Isolated magnetic flux distribution
Flux lines of the isolated magnetic flux
Isolated current phase angle versus torque
Additionally, a superimposed direct current characteristic analysis can also be performed. In transformers and reactors that have direct current superimposed on the driving current, the magnetization properties of the direct current for the inductance are smaller than the values that are measured because the magnetic flux in the primary magnetic pathways stops varying in the saturation region. The superimposed direct current characteristics can be evaluated in JMAG-Designer 10.4 by obtaining the operating points of the direct current components, and then analyzing the alternating current components using the frozen permeability. Even greater analysis accuracy can be attained by artificially reproducing the minor loop of hysteresis if the magnetic flux density/minor loop permeability properties are available.
Magnetic flux density versus relative permeability
Analysis using magnetic flux density versus relative permeability
Electric Field Analysis
Electric field and current distribution analyses can now be performed in JMAG-Designer Ver. 10.4.
Those who have been using JMAG-Studio to perform electric field analyses can now take advantage of the rich pre/post processing features and usability of JMAG-Designer.
The capacitance of capacitors and the effects of motor stray capacitance and coil geometry on the current distribution can be analyzed and evaluated. The reliability and lifespan of motors that axial voltage occurs deteriorates if a PWM inverter power supply is used. Axial voltage is produced by the stray capacitance of motors. The reliability of motors is improved by understanding the stray capacitance via electric field analysis and investigating ways to prevent it.
Analyses accounting for the heat sources of capacitors and the temperature dependency of electric properties can also be performed by coupling magnetic and thermal analyses. Don't hesitate to take advantage of all these new analysis features.
Electric field analysis of wire in slots
Capacitance analysis of a capacitor
Realizing Multilateral Evaluation Through Links to Third-party Software
The development of electromechanical equipment today demands designs that are able to establish bilateral trade-offs yet satisfy the requirements from electromagnetic, thermal, and structural points of view.
JMAG offers an optimal analysis environment to examine machine designs from multiple perspectives via a link to the structural/thermal analysis CAE software Abaqus.
Magnetic field phenomena obtained in JMAG can be utilized as input to the structural/thermal analyses in Abaqus. The results obtained in a structural analysis in Abaqus can also be utilized as input to the magnetic field analysis in JMAG.
A comprehensive vibration analysis can be achieved by applying the electromagnetic force obtained in JMAG to LMS Virtual.Lab.
Noise analysis using LMS Virtual.Lab
Induction heating analysis (IH) by linking JMAG-Abaqus
This article has introduced the latest features in JMAG-Designer Ver. 10.4. Don't hesitate to try all of the new and easy to use features that are now available in JMAG-Designer Ver. 10.4.
1. Implement JMAG
2. Introducing JMAG-Designer Ver.10.4
3. JMAG Application Catalog
158 - Superimposed Direct Current Characteristic Analysis of a Reactor Accounting for the Minor Hysteresis Loop
159 - Influence Analysis of Dimensional Tolerance using Morphing
4. Exhibition Report
- JMAG Users Conference 2010 Report -
- JMAG USER CONFERENCE 2011-