When creating a design PI Expert automatically designs an optimized power transformer that uses the smallest core and bobbin for the specified output power. PI Expert also gives you the ability to optimize designs using only the cores you have specified. It is important to include cores and bobbins that are able to deliver the power specified in your design; otherwise, optimization will fail.
There are different ways to specify the cores and bobbins that you would like the software to use during optimization:
You can control transformer (core and bobbin combination) during optimization through Transformer Component Library and Component Sets. Using the Component Library you can add custom transformers by entering the core and associated bobbin data. You can then create a component set that uses these custom transformers. You can also include or exclude any combination of the built-in transformers in your component set. The transformers used in the component set will then be available in the Solutions Filter if it is enabled before optimization.
You can also use the Solutions Filter form directly to select only a certain range of cores to use. Use the Core Start drop down menu to select the core you want optimization to first try to use. Use the Core End drop down menu to select the last core to be used during optimization. During optimization, each core in the range you have selected will used during the optimization process.
You can use the Solutions Filter form to force optimization to use a particular core as well. To do so, select the same core in the Core Start and Core End drop down boxes.
If you would like to use one of the non-preferred cores during optimization, you can create a custom transformer with the same specifications as that of the non-preferred core you want to use since custom cores can be used for optimization. For details see Custom Transformer.
It is important to be careful when limiting the number and the range of transformers during optimization. The software may not be able to optimize your design successfully using the transformers you have chosen. The failure to optimize can happen, for example, due to power limitations of the core or inadequate winding window area of the transformer.
PI Expert allows you to modify the output stacking configuration through the Stacking dialog for more control over the design of the power transformer including preforming optimization using your manually entered stacking configuration. However, placing constraints on the stacking configurations the software uses during optimization can result in the failure to optimize or to meet your specified tolerances.
You can select a range of the number of main secondary turns to be examined using the Solutions Filter manually. You can force the software to use a specified number of secondary turns on the main output by setting the value of the starting turns range equal to that of the end of the range in the Solutions Filter. Trying to modify the range of turns examined during optimization can result in the failure to optimize or to meet your specified tolerances.
You can also modify the secondary winding order, the wire gauge or foil thickness and the start and termination pins for each winding using the Secondaries dialog. PI Expert allows for the modification of nearly every aspect of power transformer design, construction and documentation. See the Winding Construction help topics for more information.