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Transformers and Inductors for Electronics Applications


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Free Software

Information for Designers




Optimized winding shape image.

ShapeOpt is a free program that optimizes the shape of a high-frequency inductor winding to achieve lower power losses, written by Jiankun Hu, Charles Sullivan, Rob Jensen, Dan Gestwick, and Reid Hutchins.

Typical inductor designs fill as much of the bobbin as possible to decrease dc resistance. However, it is undesirable to place wire close to the core gap, because the high fringing B field in this region can lead to excessive eddy current losses. Shapeopt finds the optimal placement of the wire such that total power loss is minimized.

Using this method, it is possible to achieve lower power losses than in a distributed or quasi-distributed gap design.  First, the program calculates the field due to the gap and the windings using the image method (2-D analysis). Finite-element analysis  has shown that this two-dimensional analysis is very accurate. Finding the shape for minimum loss requires an optimization because changing the wire placement will change the field in the whole window. For more information about the specialized algorithm used, see related papers and publications.

What Software Do I Need and How Do I Run It?

There are two versions of ShapeOpt. The web-based version runs the calculations on our web server. The downloadable version is for use with MATLAB Version 5 or 6, available from Mathworks for a variety of platforms. The two have similar capabilities, but the downloadable version has a few more options and allows watching the optimization process as it progresses.

Run ShapeOpt online.

Download ShapeOpt  for use with  MATLAB software. The directory the shapeopt.m file is placed in must be on the Matlab path in order to run it from the Matlab command window.

Help and Instructions

For comments or questions e-mail: Charles.R.Sullivan@dartmouth.edu.
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