ProductsMotor Design ToolJMAG-Express Public (Free)

JMAG-Express Public is software for electric machine design.

JMAG-Express Public the latest information

January 30, 2018: JMAG-Express Public 201801 has been released.

There is now more freedom in serial-parallel circuit combinations.

Designs from JMAG-Express can be evaluated in detail using JMAG-Designer.
How to import designs to JMAG-Designer is explained in the videos.

Sending Designs to

JMAG-Express Public

JMAG-Express Public allows calculation of basic motor properties in one second.
Just by entering the geometry template, materials, winding, and drive conditions as parameters, you can obtain the induced voltage constant, torque constant, inductance properties, current vs. torque properties, revolution speed vs. torque properties, iron loss/copper loss properties, etc. in a split second. When the desired power (W) is specified, the size and comparative loading needed to achieve it are calculated automatically.

Design a Motor in 5 Minutes
Design a Motor in 5 Minutes

Why is JMAG-Express Public free?

JMAG-Express Public can initially be used upon issue of a license valid for one week.
From then on, we will extend the license for users completing a questionnaire sent out periodically.
JMAG-Express Public will remain free of charge as long as the questionnaires are completed and returned.

Obtain Motor Characteristics Instantly Link to Circuit/Control Simulators!

Displays motor characteristics form design specifications with one click
Accounts for magnetic saturation
Requires no analysis experience

Obtain Motor Characteristics Instantly Link to Circuit/Control Simulators!

Output: Torque, Efficiency, Copper Loss, Iron Loss, Inductance, Torque Constant
Target motor: PMSM, IM(Three-Phase/Single-Phase), SRM, permanent magnet DC motors, synchronous machines





permanent magnet DC motors
permanent magnet
DC motors
synchronous machines

Result Display
Result Display

Design sheet
Design sheet (Click to enlarge)
Graph value
Graph value

JMAG Function Videos

Overview of Motor Design

Compare and investigate design proposals

Parametric Analysis

Show / Hide Evaluation Items

Specifying the End Ring
Cross Section

Sending Designs to

JMAG-Express Public News

January 30, 2018 There is now more freedom in serial-parallel circuit combinations.
Fixed an issue that caused JMAG-Designer to fail when "Send to JMAG-Designer" was executed using a template exported using the JMAG-Express Public 2017.07 version.
July 27, 2016 Characteristics evaluation for wound-field AC synchronous machines and externally excited synchronous machines are now supported.
These can also be used as analysis templates in JMAG-Designer.
Sizing functionality has been improved.
Reference hints to review design parameters before sizing.
Mar 30, 2016 An issue has been fixed which prevented some parameters for a parametric evaluation from functioning normally.
Jan 29, 2016 Operability of GUI in "Import DXF File" has been improved.
Pasting data to a table of arbitrary winding settings, copying from a table, and deleting the data selected in a table are now available. Slot settings created with Excel can be reflected to Express.
One column in a table and values such as torque constants can now be copied with Ctrl+C.
Jul 29, 2015 Account for Induction Motor End Ring Cross-Section Geometry
Inherit Number of Slots / Poles
Specify the Number of Decimal Places
Interface Improvements
Apr 24, 2015 Automatically calculates wire diameter and number of turns from slot fill factor.
Improved DXF file loading function.
Jan 28, 2015 The design comparisons is largely revised.
Automatically calculate maximum revolution speed.
Characteristics values of the specified revolution speed can be confirmed.
Nov 27, 2014 Pole numbers and slot numbers can be specified with the sizing function
Power factor can now be verified
Sep 29, 2014 Support for importing CAD data
July 30, 2014 User-specific material data can be specified
May 30, 2014 Calculation accuracy has increased
Selection of result evaluation items, as well as parametic calculation has become clearer
Mar 28, 2014 You can now choose to show / hide the graph and table of the [Characteristics] tab.
Supports parametric calculation function.
Jan 27, 2014 Now enables checks of current density and back yoke magnetic flux density.
The improved Specifications/Characteristics tab is now easier to see.
Dec 20, 2013 Now supporting Single-Phase induction motors
Check design proposal history, results graph and specification tables on a single screen
Sep 30, 2013 Strengthened the result evaluation function
July 30, 2013 Support for permanent magnet DC motors
May 31, 2013 Many new results evaluation items added
Support for series/parallel circuits
Improved robustness for geometry templates
Mar 29, 2013 Support for delta connections and parallel circuits (fully parallel)
Improved the operability of changing geometry
Added selectable materials
JMAG-RT motor modeling export support for SRM
Nov 30, 2012 Newly supported SRM and added optimization functions
Sep 28, 2012 Sensitivity Analysis
July 31, 2012 Improved Accuracy for Induction Motors and Enhanced Geometry Template Functions
May 7, 2012 Enhanced coil settings
Export setting parameter files
July 12, 2011 Sizing Feature for JMAG-Express Geometry
July 21, 2010 Link JMAG-Designer and JMAG-Express
Specify Correction Coefficients for Magnets and Loss
Apr 20, 2010 Two new geometry templates are now available
Magnetomotive force can now be obtained in JMAG-Express
in addition to the inertia moment and mass.
Dec 20,2009 JMAG-Express can now generate JMAG-RT models
Nov 11,2009 JMAG-Express now supports induction machines
Sep 17,2009 Drive conditions can be specified in JMAG-Express
July 15,2009 Six New Templates Available for JMAG-Express
June 1,2009 JMAG-Express now supports the export od DXF files


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