Design of a Single Ultra-Low-Loss Magnetic Ballast for a Wide Range of T5 High-Efficiency Fluorescent Lamps

A patent-pending single design of an ultralow-loss (ULL) magnetic ballast for T5 high-efficient (T5-HE) fluorescent lamps rated from 14 to 35 W is presented. Based on the use of a nonlinear physical low-pressure discharge lamp model, it is discovered that the same set of ballast parameters can be chosen for operating T5-HE 14-, 21-, 28-, and 35-W lamps at their respective rated power at a mains voltage in the range of 220-240 V. With energy efficiency higher than and lifetime much longer than their electronic counterparts and being recyclable, the ULL ballasts offer a more environmentally friendly solution to T5-HE lamps than electronic ballasts. This single-ballast design offers great convenience to both ballast manufacturers and users, because only one product design can cover a range of the most popular T5-HE lamps. Both theoretical analysis and experimental results are included to confirm the validity of the proposal.