Electronic ballast for discharge lamps
US6650067B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 2002 |
| Grant date | Nov 18, 2003 |
| Priority date | — |
| Expiry date | May 14, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electronic ballast operates a gaseous discharge lamp. The electronic ballast includes a filter circuit for removing noise from an electrical power signal. The power factor of the filtered power signal is adjusted by a power factor correction circuit. The power factor correction circuit includes a programmable inductor circuit having a plurality of selectable inductance values for varying the amount of power factor adjustment to accommodate operation of different lamp types and/or different lamp wattages. A power supply circuit converts electrical power received from the filtered power signal to provide low level power for operating the electronic ballast. An output circuit receives the corrected power signal produced by the power factor correction circuit and produces an electrical signal to ignite and operate the discharge lamp. The output circuit includes an ignition circuit for producing an oscillating voltage signal to ignite the lamp, and an operating circuit produces an oscillating current signal which operates the discharge lamp after ignition. A control circuit controls the operation of the electronic ballast. A current monitor is used to determine when the lamp is ignit…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.