Design of a voltage-fed quasi-E resonant inverter for cooker magnetrons

This paper presents a voltage-fed quasi-E resonant inverter for cooker magnetron drives. The design of voltage-fed quasi-E circuits has a choice of using one switch or two switches. Usually, one-switch circuit and two-switch circuit are respectively used in AC110V and AC220V microwave ovens. In the circuit, the filament heating and current stabilization of magnetrons are all supplied with a loose-coupling high frequency transformer. Two-stage LC resonant operation is designed for achieving zero-voltage switching and decreasing the voltage stress of transistors. To demonstrate the analysis and design, this paper implements a one kilo-watt prototype circuit.