Low-cost high power-density electronic ballast for automotive HIDlamp

摘要

A low-cost high-efficiency high power-density electronic ballastnfor 35 W automotive high intensity discharge (HID) is presented alongnwith the results of theoretical computations and experimental tests. Thenballast circuits is based on a 100 kHz resonant inverter, a half-wavenrectifier and a 400 Hz operated square-wave inverter. The converternoperates at zero turn on losses, nearly zero turn off losses, and at anreduced electromagnetic interference level. The ballast circuit isndesigned to prevent inappropriate operations due to the acousticnresonances. The lamp voltage waveform has limited dv/dt and no DCncomponent contributing to a long operating life of the lamp. Anbreadboard of the electronic ballast was designed and experimentallyntested on a 35 W lamp, for a DC input voltage ranging from 9 V to 16 V.nThe electronic ballast performs all the features required to turn-on,nwarm-up and drive at the steady state a 35 W HID lamp and operates at anmaximum steady state efficiency Η=84%,