High frequency power devices provide many benefits, but as switching frequency rises so does the potential for switching loss. Effective design minimizes that loss while maintaining the benefits of high frequency switching. There is no one-size-fits-all solution; each device must be carefully designed to fit the application. Several factors contribute to high frequency device efficiency.
- Core material performance can vary significantly with switching frequency. For example, a material that performs well at 100 kHz can have five times greater core loss at 300 kHz. A different material at 300kHz can reduce core loss by over 30 percent.
- Core temperature can be another critical factor. It is not unusual for a particular material’s losses to vary by as much at 50 percent as temperature changes. To further complicate the matter, different materials’ response to temperature can vary greatly. Some are relatively stable over a range of temperatures while others lose efficiency as temperature rises above or falls below optimum
- Leakage inductance may be desirable or undesirable. Capacitance is generally undesirable. Both can be controlled through careful attention to winding configuration. Desirable leakage inductance, for example, can be maintained using single section bobbins.
- To control capacitance, on the other hand, the right winding configuration can reduce it by 75 percent, based on winding configuration without changing package style, bobbin, or the number of turns.
- A number of tools and skills go into adjusting these various factors to produce the most efficient high frequency power device for a particular application. 3D finite element analysis (FEA) and Maxwell 3D are sophisticated software packages. We use them to analyze flux distribution and leakage inductance losses due to skin and proximity effects, optimizing performance and reducing time to market.
- Other factors can include selection of appropriate Litz wire – bundled, stranded wire of optimal strand size for the particular switching frequency.
At Precision, we have the software tools, experience, and capabilities to design and build high frequency devices tailored for your application. We know core materials, bobbin design, Litz wire, and winding configuration and put that knowledge to work to design and build efficient high frequency power components for your products.
Precision Inc. We do amazing things.