Analysis and design of a self-oscillating class E ballast for compact fluorescent lamps

The Class E inverter is the basis for a low-cost high-frequency ballast, but the control system is more complex than the selfoscillating Class D inverter. The added complexity neutralizes any cost savings gained by the single switch inverter. This paper explores a novel self-oscillating Class E ballast from a design perspective. A qualitative analysis shows how this selfoscillating system operates, from startup, through ignition to the steady state. Optimum component values are found from a quantitative analysis of the inverter. This mathematical model is the basis for the design methodology. Analytical results are compared with the physical model.