Analysis of a self-oscillator in the modified half-bridge type inverter

In order to decrease input harmonic currents of switching converters, a combined circuit configuration that the switching converter circuit itself has the function of the input current active filter and output voltage regulator has been investigated. In this paper, a self-excited oscillator as a controller applied to this combined circuit for the electronic ballast of the fluorescent lamp with high frequency is analyzed. As a result, the relationship between the peak current and the conduction time interval of the switch device is clarified. This relationship is useful to reduce the input harmonic current effectively