EMI filter inductor with winding capacitance cancellation
This technology improves how inductors — coils used to filter unwanted electrical noise — perform at high frequencies. The core problem is that inductors have unavoidable internal capacitances (called parasitic capacitances) that cause them to stop working properly at higher frequencies, limiting how well they can filter interference. This invention splits the inductor winding into sections and adds small capacitors in a clever arrangement so that the parasitic capacitance effects cancel each other out rather than accumulate. The result is an inductor or EMI filter that maintains its filtering performance well beyond the frequency limits of conventional designs.
What you could build
An improved EMI filter component or module for power supplies, motor drives, and switching electronics that maintains attenuation performance at higher frequencies than standard designs; buyers would be power electronics manufacturers, EV drivetrain suppliers, and industrial equipment OEMs needing regulatory compliance on conducted emissions.
Who in Virginia should care
Defense electronics and power electronics companies in Northern Virginia and the Hampton Roads corridor — particularly those building power conditioning or EMI-hardened equipment for military platforms — would have direct interest.
Readiness: Lab validated
Concept — described but not yet demonstrated. Lab validated — supported by experimental results in the patent. Prototype likely — the text describes a built, working embodiment.
Readiness is inferred from the patent text, not from a lab visit.
The record
- Inventors
- Shuo Wang, Fred C. Lee
- Granted
- June 30, 2009
- Status
- Granted patent
- Patent number
- 7554423
Ready to talk?
Virginia Tech Intellectual Properties handles licensing for this technology.
Prosim summaries are generated from public patent text and are not legal advice.