Discharge lamp typically a sodium high-pressure discharge lamp, from an a-c power network

US5739644A · kind A · utility

Assignee

• Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH · DE

Inventors

• Franz Bernitz · Unterhaching, DE
• Andreas Huber · Holzgerlingen, DE
• Guenther Hirschmann · Munich, DE
• Michael Boenigk · Berlin, DE

Key dates

• Filing date: Mar 7, 1995
• Grant date: Apr 14, 1998
• Expiry date: Mar 7, 2015

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S315/07
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

To provide for effective control of a discharge lamp, typically, a sodium gh pressure discharge lamp, which operates in two phases, namely, a power pulse phase, followed by a holding phase, without extensive and complex electronic circuitry, two individual oscillator systems are provided, one for each phase; the oscillator systems include a first power burst oscillator formed as a first half bridge by two transistors (T1, T2), and an individual connecting current limiting inductance (L1) to the lamp (E), and a second oscillator including a two-transistor second half bridge (T3, T4) and an individual current limiting inductance (L2) coupled to the lamp. The respective oscillators are controlled, in a closed control loop, by a burst generator (BG) and a holding pulse generator (SG), each of which provide their signals to a logic circuit (LK) which provides for exclusive control of the respective first or second half bridge. A lamp voltage sensing circuit (C4, R2) taps lamp operating voltage, which is compared with a command signal to control through a repetition frequency control generator (WG), the recurrence rate of the bursts from the power bursts generator (BG). The lamp starting…