Single stage self-oscillating HPF electronic ballast

This paper presents a single stage self-oscillating high power factor (HPF) electronic ballast more suitable for both low power levels (because it operates in discontinuous conduction mode) and low AC mains applications (since it employs an input doubler rectifier). The electronic ballast is based on a high frequency dither signal, which shapes the input current in a sinusoidal waveform. In order to reduce the electronic ballast components the self-oscillation technique has been employed. An electronic ballast prototype operating at 25 kHz has been implemented to drive two 40 W straight-type fluorescent lamps from a 127 V utility line. High power factor is achieved even though the electronic ballast drives just one fluorescent lamp. The experimental results demonstrated the electronic ballast operation.