Design and analysis of dimming electronic ballast

Fluorescent lamps have become the most favored lighting sources in many applications. A dimming electronic ballast for fluorescent lamps using a half bridge inverter is presented in this paper. By using the frequency-domain analysis method, the corresponding circuit components can be computed. The relationships among the switching frequency, resonant frequency, duty cycle, lamp starting voltage, and lamp steady state current are addressed. The driven inverter using a PWM control integrated circuit provides the electronic ballast with the ability to vary the light output. The light output controlled by both the pulsewidth modulation method and the variable frequency method is discussed. The experimental results indicate that the efficiency of the electronic ballast is increased by 20% in comparison with the electromagnetic ballast. Also, the light output of the fluorescent lamp can be varied smoothly from 600 Lux to 3400 Lux in that the energy saving can be considerably higher in the smart lighting systems.