Instant start for an electronic ballast preconditioner having an active power factor controller
US5834906A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 1995 |
| Grant date | Nov 10, 1998 |
| Priority date | — |
| Expiry date | May 31, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/05
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electronic ballast for driving a fluorescent lamp includes an electromagnetic interference (EMI) filter and power circuit, a preconditioner coupled to the EMI filter and power circuit and an inverter circuit coupled to the preconditioner for energizing the fluorescent lamp. The preconditioner includes an active power factor controller and a boost circuit which is controlled at least in part by the active power factor controller. The active power factor controller has a reference voltage input to which is applied a reference voltage. At start up, the inverter provides a time varying signal which is rectified. At least a portion of the rectified signal is fed back to the reference voltage input of the active power factor controller to boost the reference voltage to a level above normal so that the active power factor controller will cause greater current to flow through the boost circuit, causing the boost circuit to generate a direct current (DC) rail voltage more rapidly, which rail voltage is provided to the inverter circuit to ignite and operate the fluorescent lamp.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.