Microcontroller-based electronic ballasts for high-intensity discharge lamps

Abstract

This chapter deals with the use of digital control applied to discharge lamp electronic ballasts with a special focus on high-intensity discharge (HID) lamp ballasts. HID lamp ballasts is one of the power electronics fields in which digital control is well justified. HID lamps require a complicated process of ignition, warming-up, and lamp current and power regulation. Each of these operating stages requires a precise timing during which the measurement of lamp parameters results critical to take the correct decision for a proper operation of the ballast. In addition, HID lamp ballasts deal with very high voltages, which can reach up to tens of kilovolts for hot re-ignition. These high voltages, along with the fact that HID lamps operate at high temperature and pressure, makes safety one of the important issues in HID lamp supply. In this context, microcontroller-based electronic ballasts are an excellent option to achieve all these stringent requirements.