Area-Product Method Can Simplify Core Selection—But Beware Of The "Constants"

Focus:

A popular method for simplifying core selection for a given transductor (transformer or coupled inductor) power level is the area-product method. This article reveals the assumptions of the method. The area-product method of core sizing is based on the winding-window turns maximum constraint, NW = AW/(Ac/kp) = AW/Acwp, where Aw is the winding window area; kp < 1, and is the wire packing factor and Ac is the conductive area of the wire. Then Acwp is the larger area occupied by a single turn, taking the packing factor into account. The area-product method chooses core size from the equation, area product = A·Aw, where A is the magnetic-path cross- sectional area of the core. In applying the above equation, it is typically assumed that certain terms such as kp are constant. However, these terms are actually dependent on variables such as wire size and other parameters. These relationships are explained here.

What you’ll learn:

• How to apply the area-product method of core selection for transformers or coupled inductors
• How to understand the variability of the “constants” in the area-product method of core selection
• How to understand the variation in wire packing factors as a function of wires size

View the Source

Author & Publication:

Dennis Feucht, Innovatia Laboratories, Cayo, Belize, How2Power Today, Aug 17 2015

This article summary appears
in the HOW2POWER Design Guide.

The Design Guide offers
organized access to
hundreds of articles
on dozens of power conversion
and power management topics.

The Design Guide search results
include exclusive summaries
and accurate "how to" analysis
to help you make faster,
more informed decisions.

Search
for more articles