High Frequency Magnetics
High Frequency Magnetics
The world of modern power supply continues to change and evolve, demanding ever-more innovative designs to handle demanding applications. Today’s switch mode power supply (SMPS) power transformers and inductors must now be designed for power levels that have migrated well into the medium-to-high kilowatt range. Whether it’s for grid-level power conversion in wind energy, large-scale solar converters, hybrid vehicles, or industrial equipment drive trains, high frequency magnetics present unique challenges.
Specifications and Applications
The challenge of designing the core for high frequency magnetics must not be underestimated. Choosing the right core material is one of the most basic, yet crucial challenges. The main issue here is that the volume of the core does not scale linearly with power levels. High power levels demand larger core volumes than lower power levels, and this challenge is independent of frequency.
Ferrites are an obvious choice because they result in less losses, but don’t often come in sizes adequate for delivering 10 kW power levels and higher. They also tend to be increasingly brittle the larger they get, which means they don’t work well in applications that involve lots of vibrations or shocks, such as industrial equipment or hybrid vehicles.
Materials other than ferrites tend to be more expensive and result in greater losses. Larger cores also can’t support higher power densities as well as smaller cores, resulting in lower gauss levels.
