Arc discharge ballast suitable for automotive applications
US5036256A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 21, 1990 |
| Grant date | Jul 30, 1991 |
| Priority date | — |
| Expiry date | Jun 21, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit for starting and operating a high intensity discharge (HID)lamp in a dc mode includes a pulse width modulator (PWM) coupled to first and second direct current input terminals. The PWM includes a high frequency generator driving a pair of semiconductor switches. A first transformer having primary and secondary windings is coupled to the semiconductor switches. A rectifier and voltage multiplier circuit converts the voltage across the secondary winding of the first transformer to a direct current voltage. A first energy storage circuit coupled to the rectifier and voltage multiplier circuit stores energy for generating a high voltage spike which initiates a glow condition in the lamp. A secondary energy storage circuit, which stores energy for application to the HID lamp during starting, insures proper glow-to-arc transition. The starting and operating circuit further includes a second transformer having first and second secondary windings coupled to the HID lamp and a pulse winding coupled to the first energy storage circuit. Preferably, the windings of the second transformer are adapted to apply a negative-going pulse across the lamp. The application of a negative-going p…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.