A Single-Stage High-Power-Factor Constant-Power Electronic Ballast for Metal Halide Lamps
碩士 === 國立中山大學 === 電機工程學系研究所 === 97 === This thesis presents a single-stage high-power-factor electronic ballast for metal halide lamps. The proposed ballast integrates a buck-boost converter, a buck converter and a full-bridge inverter into a single power conversion circuit. The buck-boost converter...
| Main Authors: | , |
|---|---|
| Other Authors: | |
| Format: | Others |
| Language: | zh-TW |
| Published: |
2009
|
| Online Access: | http://ndltd.ncl.edu.tw/handle/70126342482532899193 |
| Summary: | 碩士 === 國立中山大學 === 電機工程學系研究所 === 97 === This thesis presents a single-stage high-power-factor electronic ballast for metal halide lamps. The proposed ballast integrates a buck-boost converter, a buck converter and a full-bridge inverter into a single power conversion circuit. The buck-boost converter is designed to be operated at the discontinuous conduction mode (DCM) with a constant duty ratio at a fixed switching frequency to provide a constant lamp power and to achieve a high power factor for a given ac input voltage. The full-bridge inverter supplies a square-wave current for the lamp at a low frequency the same as the line frequency to avoid acoustic resonance. For the universal input voltage ranged from 90 V to 264 V, the lamp remains at the rated power by controlling the duty-ratio of the buck converter.
The circuit operation is analyzed in detail to derive the design equations. An electronic ballast for 70 W lamps is designed and tested. Computer simulations and experimental measurements are provided to verify that the proposed ballast has the merits of a nearly unity input power factor, a high efficiency greater than 82 % and can drive the lamp at a constant power.
|
|---|