Ballast dimmer with passive power feedback control
US5917717A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1997 |
| Grant date | Jun 29, 1999 |
| Priority date | — |
| Expiry date | Jul 31, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/355
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit arrangement for the high-frequency operation of a discharge lamp comprises a first rectifying circuit (D1-D4) for generating a DC voltage across a first capacitor (C1) from a low-frequency supply voltage. A DC/AC converter (IV) for generating a high-frequency AC voltage at a frequency f from the DC voltage is coupled to a load branch (B) provided with coupling means (T3, T4) for coupling the discharge lamp (Li) to the load branch. The load branch connects a junction point N1 of the DC/AC converter to a junction point N2 between the first rectifying circuit and the first capacitor. A second rectifying circuit for converting a high-frequency voltage generated by the DC/AC converter into a DC voltage is coupled to the first capacitor and to a junction point N3 in the load branch. A control circuit controls the power consumed by the discharge lamp through variation of the frequency f. The coupling means are connected between the junction point N2 and the junction point N3 in the load branch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.