Current-clamped resonant inverter: analysis and design as a high pressure sodium lamp ballast

The aim of this paper is to show the possibilities of the current-clamped resonant inverter as a high intensity discharge (HID) lamp ballast. The steady-state analysis is performed and a prototype for a 150 W high pressure sodium lamp is designed. Prototype implementation, including igniting circuitry, and experimental results are also shown. The proposed topology is oriented to work with a previous PFC stage in order to implement a high-power-factor high-efficiency ballast for HID lamps.