A self-oscillating h.f. power generator with a Class E resonant amplifier

Self-oscillating h.f. power generators with a Class E amplifier are used as industrial high-efficiency h.f. power sources. In the paper a modification of the classic Class E generator by applying an additional capacitor in the matching and feedback circuit is presented. The proposed solution increases the degree of freedom in the generator design and can noticeably reduce its cost by eliminating the need for the use of high-value h.f. capacitors in the feedback loop divider. The self-oscillating Class E generator (150 W/6.78 MHz) with the proposed modification has been designed, built and its parameters were measured. Theoretical predictions were in a good agreement with experimental results. Moreover, the burst control method of the output power in the generator has also been presented.