• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2085-2087
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• 1998

This paper presents the design method of a dimming electronic ballast for fluorescent lamps using a frequency control IC, and investigates the effects of circuit variables on its dimming characteristics. It is shown that effective dimming is possible with IC IR2151 for frequency control, and this leads to a feasible design of more smaller and cheaper dimming ballast. Five ballasts different in the values of the series inductance and capactance are designed, and their dimming characteristics are compared. As the result, the dimming range becomes more broader as the series inductance gets smaller and the capacitance larger. Thus appropriate selection of the values of L and C should be made according to the types of application site.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.6
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• pp.8-14
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• 2001

MetalHalid lamps have good efficiency, good color rendition and good focusing capability. But the shortcoming of metalhalid lamps is blown as acoustic resonance phenomena in the arc tube. Such acoustic resonance produce annoying fluctuations in the intensity and distribution of the emitted light, they can raise the voltage to the point where the arc is extinguished and they can move the arc close enough to the wall to cause local overheating and tube cracking. The objective of this research is to reduce acoustic resonance in the arc tube of the Pulse Start MetaIHaide lamp(MH200[W]). To reduce the acoustic resonance phenomena the electronic ballast was designed for high frequency operation with the constant frequency sinusoidal wave of 89[kHz] in the 84.6[kHz]∼94.2[kHz] range. Experimental results show that the acoustic resonance phenomena are not in the arc tube of Pulse Start MetalHalide lamp (MH200[W]) .