Novel control strategies for HPS lamps driven by electronic ballast

A novel electronic ballast for 400 W HPS lamps is presented in this paper. During the warm-up period, constant frequency control strategy is employed to achieve the fast turn on characteristics of HPS lamp. A simple PI compensator is used in order to improve the performance of electronic ballast in the steady state. The 4.5 kV ignition pulse generated by the ignitor is ample for the ignition of the lamp under study. The lamp voltage and current waveforms suggest that the 400 W HPS lamp driven by the proposed electronic ballast is purely resistive. Experimental results from a laboratory prototype show the feasibility of HPS lamp operating at high frequency.