T-filter for reducing disturbances generated on a power grid by an active filter
US7245045B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 2002 |
| Grant date | Jul 17, 2007 |
| Priority date | — |
| Expiry date | Sep 18, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E40/40
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An active filter (4) for compensation of variations in an apparatus' (3) current consumption from a power grid (1) as a cause of variations in the apparatus electrical load, through active frequency filtering and dynamic compensation of reactive energy/current. For each of the power grid's phases (a, b, c) the active filter includes a transistor bridge (Ta, Tb, Tc) connected between each phase and a DC-link (7). The active filter includes a filter circuit of LCL-type, arranged to reduce disturbances on the power grid caused by the active filter itself. The active filter further includes a control device (9) for calculating, with a given working frequency (f), points in time at which the transistor bridges are set to reverse the current direction through the DC-link, and the filter circuit is preferably adjusted to that working frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.