Low power 60 kHz electrodeless fluorescent lamp for indoor use

This paper presents a low power electrodeless fluorescent lamp which operate at 60 kHz. Its ballast was newly designed from original 210 kHz model. Comparisons of efficacy and electro-magnetic interference (EMI) are made between 60 kHz and 210 kHz lamps. Basic theory and equations for low frequency operation are derived. To reduce losses of its toroid cores, only low power electrodeless lamps are suitable for low frequency operation. The optimal frequency for low power lamp which can maintains its efficacy is around 50-70 kHz. A prototype of 40W electrodeless lamp and ballasts were designed and implemented. Experimental results show that the EMI level and efficacy of 60 kHz lamp are better than 210 kHz. Also it can share the same electronic ballast with the lamps that have electrodes.