Design and implementation of frequency-modulated electronic ballast for metal-halide lamps

A two-stage, frequency-modulated (FM), high-frequency-driven electronic ballast for metal-halide (MH) lamps is proposed. The presented ballast consists of a power-factor-correction (PFC) converter as the first stage, a half-bridge series-resonant parallel-loaded (HB-SRPL) inverter as the second stage, and a frequency-modulation controller. The advantageous features of the high-frequency-operated ballast are its compact size and reduced weight. With constant-frequency control, the switching frequency of the ballast must be carefully designed within a frequency window that is free from acoustic resonance, and the envelope of the lamp current is large owing to the DC-bus voltage ripple that occurs on the PFC output. However, if the switching frequency of the inverter is operated outside of the stable operation window or if the energy of some eigenfrequency is sufficiently higher, then acoustic resonances will exist. An FM-controlled electronic ballast for MH lamps is proposed. The switching frequency of the HB-SRPL inverter, whose centre frequency is intentionally designed at a frequency at which acoustic resonances occur, is periodically modulated by the voltage ripples of the PFC output. The presented ballast offers a lower envelope of lamp current in order to expand the power spectrum of the lamp and to decrease the energy of the eigenfrequency that supplies the lamp. Owing to its FM operation that allows for an adequately modulated index, no acoustic resonance occurs. The ballast offers cost-effectiveness, a simple control circuit without an external modulation signal, and a low crest factor (<1.45). Design guidelines and experimental results are presented for a 70 W MH lamp ballast that utilises the FM control method with universal-line input voltage

[1]  S. Ben-Yaakov,et al.  A MHz electronic ballast for automotive-type HID lamps , 1997, PESC97. Record 28th Annual IEEE Power Electronics Specialists Conference. Formerly Power Conditioning Specialists Conference 1970-71. Power Processing and Electronic Specialists Conference 1972.

[2]  F.Z. Peng,et al.  A novel two-stage acoustic resonance free electronic ballast for HID lamps , 2002, Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344).

[3]  H. Witting.  Acoustic resonances in cylindrical high‐pressure arc discharges , 1978 .

[4]  Jiann-Fuh Chen,et al.  A high power factor electronic ballast of projector lamps with variable frequency control , 2002, 2002 IEEE 33rd Annual IEEE Power Electronics Specialists Conference. Proceedings (Cat. No.02CH37289).

[5]  P. Morse.  Vibration and Sound , 1949, Nature.

[6]  Sam Ben-Yaakov,et al.  The simplest electronic ballast for HID lamps , 1996, Proceedings of Applied Power Electronics Conference. APEC '96.

[7]  José Marcos Alonso Alvarez,et al.  Electronic ballast for HID lamps with high frequency square waveform to avoid acoustic resonances , 2001, APEC 2001. Sixteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.01CH37181).

[8]  B. Cook.  New developments and future trends in high-efficiency lighting , 2000 .

[9]  R. Zane,et al.  Custom spectral shaping for EMI reduction in high-frequency inverters and ballasts , 2005, IEEE Transactions on Power Electronics.

[10]  M. Sugiura.  Review of metal-halide discharge-lamp development 1980-1992 , 1993 .

[11]  Henry Shu-Hung Chung,et al.  A comparative study of carrier-frequency modulation techniques for conducted EMI suppression in PWM converters , 2002, IEEE Trans. Ind. Electron..

[12]  J. Waymouth.  Metal halide lamps , 1971 .