ELECTRONIC BALLAST FOR HIGH INTENSITY DISCHARGE LAMP

摘要

PURPOSE: An electronic ballast for a high intensity discharge lamp is provided to light a HID lamp with a low voltage by using an internal LC resonance start-up technique. CONSTITUTION: A power factor correction/booster circuit part(110) adjusts power factor by rectifying a commercial AC power supply. An inverter(120) connected to an output part of the power factor correction/booster circuit alternatively operates two pairs of switching devices. A main resonance start-up part(130) serially connected to an output part of the inverter provides a basic resonance circuit of a lamp. A secondary resonance start-up part(140) provides start-up resonance frequency between the lamp and the main resonance start-up part during start-up of the lamp. A controller(160) operates the lamp by controlling switching of a switching device inside of the inverter. [Reference numerals] (110) PFC boosting circuit; (180) Controller; (190) Lamp