| 摘要 |
An improved high power (40,000 watt) high intensity arc discharge power supply which provides reliable, automatic ignition control and enables precise variation of lamp power in dual AC and DC modes of operation over an extended dynamic range from 400 watts to 40,000 watts. A capacitive boost circuit is provided to supply the high voltage necessary to ignite the lamp. Upon start-up, the voltage on a boost circuit capacitor is monitored by an ignition circuit which automatically enables the ignitor when the voltage is at the required level and switches the ignitor off when the lamp starts. After ignition the boost charging circuit is disabled and the power supply operates in a normal mode. The power supply operates on a three phase alternating voltage input through a three phase bridge, switches it through a drive transistor and then supplies it to an inductor. The signal is then supplied through an H-bridge commutator to the boost circuit, the ignitor and the arc lamp itself. The circuit operates under the control of an analog computer which determines the switching rate, monitors the voltage and current, provides power feedback and generally controls the power supply. A power command input signal determines the power level at which the arc lamp will operate. Below a certain lamp current level, an oscillator circuit controlling the commutator is disabled so the lamp will operate on DC power in a "simmer" or low temperature mode. The lamp is thus operated over a large dynamic range.
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