| Title |
Design of Electronic Ballast for HID Lamps |
| Abstract |
This paper presents a design techniques for an electronic ballast of HID lamps. An electronic ballast for HID lamps usually employs a high-frequency resonant inverter and voltage-to-frequency converter to control the output and a half-bridge and series resonant circuit are chosen for the ballast. First, to design PI controller, the inverter with V/F converter is modeled with a transfer function and the controller PI gains are determined. This paper shows that an integral controller is only needed to control the current. Second a self-feedback controller is proposed. This structure, simple and robust, is analyzed and a feedback gain is determined by using the inverter model. Experimental system is built with a commercial 250W high pressure sodium lamp and the results show a validity of the proposed ballast and the total efficiency is increased by 5%. |