Integrated-magnetic filter having a lossy shunt
US5731666A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 1996 |
| Grant date | Mar 24, 1998 |
| Priority date | — |
| Expiry date | Mar 8, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F2003/106
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A two-winding, integrated-magnetic EMI filter provides damped common-mode and differential-mode inductances. The preferred embodiment of the filter has a magnetic core structure that incorporates a high-permeability C-core, a high-permeability I-core, and a low-permeability, lossy shunt. The three core pieces are assembled so as to form a structure that, similar to an E-I configuration, has two winding windows. The loss in the shunt aids in dissipating noise and it diminishes the effects of unwanted parasitic resonances by providing damping for the differential-mode inductance. Damping for the common-mode inductance is provided by losses in the C and I core pieces. Varying the reluctance of the shunt allows the differential-mode inductance to be adjusted separately from the common-mode inductance in order to tune the filter to remove desired noise frequencies. Another embodiment of the invention incorporates a high-permeability toroid core and a low-permeability, lossy shunt.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.