Multiphase driving system for LCD back-light lamps with current balancing feature

This paper presents a multiphase driving system for liquid crystal display (LCD) back-light lamps with current balancing feature. The driving system adopts multiple inverters operated with interleaving fashion to drive cold cathode fluorescent lamps (CCFL), which can reduce input current ripple. Additionally, to prevent current imbalance among lamps, a multiphase transformer is introduced in the proposed system. Compared with the conventional single-phase driving system, the proposed one can have the merit of requiring less number of transformers and lower input current ripple. A three-phase driving system with current balancing transformer has been built, from which experimental results have verified the feasibility of the proposed multiphase driving system.

[1]  Tsai-Fu Wu,et al.  Design considerations for single-stage electronic ballast with dimming feature , 2001 .

[2]  R. Redl,et al.  A novel soft-switching full-bridge DC/DC converter: Analysis, design considerations, and experimental results at 1.5 kW, 100 kHz , 1990, 21st Annual IEEE Conference on Power Electronics Specialists.

[3]  Tsai-Fu Wu,et al.  Single-stage electronic ballast with dimming feature and unity power factor , 1998 .

[4]  Mutsuo Nakaoka,et al.  Full-bridge soft-switching phase-shifted PWM DC-DC power converter using tapped inductor filter , 2003 .

[5]  M. M. Jovanovic,et al.  The LCC inverter as a cold cathode fluorescent lamp driver , 1994, Proceedings of 1994 IEEE Applied Power Electronics Conference and Exposition - ASPEC'94.

[6]  A.J. Calleja,et al.  Analysis and design of the LCC-parallel series inverter with resonant current control as HPS lamp ballast , 2001, 2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230).

[7]  S. Ben-Yaakov,et al.  Current-sourcing push-pull parallel-resonance inverter (CS-PPRI): theory and application as a fluorescent lamp driver , 1993, Proceedings Eighth Annual Applied Power Electronics Conference and Exposition,.

[8]  Tsai-Fu Wu,et al.  Self excited half-bridge series resonant parallel loaded fluorescent lamp electronic ballasts , 1995, Proceedings of 1995 IEEE Applied Power Electronics Conference and Exposition - APEC'95.

[9]  G. Bruning.  A comparative introduction of a new high voltage resonant oscillator , 1986, 1986 IEEE Applied Power Electronics Conference and Exposition.

[10]  Fred C. Lee,et al.  Analysis and design of a zero-voltage switched, three-phase PWM rectifier with power factor correction , 1992, PESC '92 Record. 23rd Annual IEEE Power Electronics Specialists Conference.