A MHz electronic ballast for automotive-type HID lamps

The compatibility of the current sourcing push pull resonant inverter (CS-PPRI) with the driving requirements of HID lamps designated for automotive headlight applications was investigated theoretically, by simulation and experimentally. The study reveals that a based ballast (CS-PPRI) complies with the automotive requirement of very fast warm up. The experimental ballast was run under zero voltage switching (ZVS) at a nominal switching frequency of 1.29 MHz while the pre-ignition switching frequency was 124 kHz. Warm up time to 80% after cold ignition was about 10 seconds.