A single-stage HID lamp electronic ballast with high PF

This paper presents a single-stage electronic ballast for the high-intensity-discharge (HID) lamp with high power factor (PF). The presented ballast consists of a discontinuous-conduction-mode (DCM) operated dual-boost converter to achieve input-current shaping, and a high-frequency combined with low-frequency square-wave-driven half-bridge-type inverter for supplying the HID lamp with low-frequency square-wave sources. The features of the proposed ballast are high PF, low total harmonic distortion (THD) of input utility-line current, cost-effectiveness and freedom from acoustic resonance. This paper presents the operational principles, design guidelines and experimental results of the proposed ballast for one 70W MH-type HID lamp operating with 110V-rms input utility-line voltage.