domingo, 15 de dezembro de 2013
Novel Two-Stage High-Power-Factor Electronic Ballast CHUN YUAN CHRISTIAN UNIVERSITY
In this thesis, electronic ballast with power factor correction for high intensity discharging (HID) lamp is presented. The proposed topology is a two-stages circuit that requires only one switch and one inductor for each stage. Power factor correction (PFC) stage is boost dc-to-dc converter operating in continuous conduction mode (CCM) to achieve low total harmonic distortion (THD) and proper output characteristics over a wide range of load (10% ~ 90% full load).
This control implementation for against broken lamp can be easily implemented with the proposed circuitry. The high-frequency supply the lamp is given by the flyback converter. Input AC voltages ranges from 90V~260V are allowable for our system with a low DC bus voltage below 450V. It is suitable for electronic ballast with medium power HID lamp. The topologies could work under the circumstance of two 250W fluorescent lamps at 66 KHz switching frequency.