Analysis of an HID-lamp ignitor using a two-stage magnetic-pulse-compression circuit

Abstract

High-Intensity-Discharge (HID) lamps have prominent features of high brightness, high efficacy, and long life. However, high voltage pulses more than tens of kilovolts are needed to restart them just after they are turned off. This paper proposes an ignitor using a two-stage Magnetic-Pulse-Compression (MPC) circuit to suppress the stress of the semiconductor switch and generate sufficiently high voltage pulses for the instantaneous restarting of HID lamps. The proposed circuit is analyzed by using equivalent circuits. The interaction of the component values is clarified, and an optimal design of circuit parameters is obtained. Analytical results are verified by experimental ones. Finally, as an example of the practical use, an ignitor for 2kW metal-halide lamp is reported. High voltage pulses with voltage peak of 50kV and pulse width of 800ns are generated by the ignitor. As a result, the instantaneous restarting of the lamp was successfully achieved.