Title :
Hybrid electronic ballast operating the HPS lamp at constant power
Author_Institution :
Escola Politecnica, Sao Paulo Univ., Brazil
Abstract :
A hybrid solid-state ballast is described that operates the HPS (high pressure sodium) lamp at mains frequency with constant power through rated life. The system utilizes two series-connected inductors and a bidirectional semiconductor switch connected in parallel to one of them. A lamp starting circuit has also been included in the ballast. The static switch, with phase angle control provided by power feedback, actuates on lamp current compensating variations of the mains voltage and/or the increase of lamp voltage. The system offers: a) an increase of lamp life and system lumen maintenance; b) power factor and total harmonic distortion of line current comparable to conventional lag ballasts; and c) operating cost savings, both in terms of energy cost and lamp replacement cost
Keywords :
lamp accessories; metal vapour lamps; power semiconductor switches; starting; switching circuits; Na; bidirectional semiconductor switch; constant power operation; energy cost; high pressure sodium lamp; hybrid solid-state ballast; lamp life; lamp replacement cost; line current; lumen maintenance; mains frequency operation; operating cost savings; phase angle control; power factor; power feedback; series-connected inductors; total harmonic distortion; Costs; Electronic ballasts; Feedback; Frequency; Inductors; Lamps; Power semiconductor switches; Reactive power; Solid state circuits; Voltage control;
Conference_Titel :
Industry Applications Conference, 1996. Thirty-First IAS Annual Meeting, IAS '96., Conference Record of the 1996 IEEE
Conference_Location :
San Diego, CA
Print_ISBN :
0-7803-3544-9
DOI :
10.1109/IAS.1996.563865
