Phase controlled LC/sub p/C/sub s/ resonant inverter applied to HID lamp control

This work presents the analysis and design of a new configuration of a resonant inverter for high-intensity discharge (HID) lamp ballast applications. The proposed inverter results from the parallel connection of two class D LC/sup p/C/sub s/ resonant inverters. The dimming control is implemented at constant frequency, modifying the phase displacement between the drive signals of each inverter. At full power operation, the inverter guarantees that the power applied to the lamp is within the recommended operation area regardless of the lamp aging. In order to achieve good repeatability of the circuit performance, the design sequence also considers the tolerance of circuit components and is verified by the Monte Carlo method. A 150 W prototype has been built to validate the design proposal.