Gas discharge lamp operating circuit computes primary circuit demand current value giving optimal lamp drive from actual current, supply voltage and transfer device efficiency

摘要

The circuit has a drive arm containing a transfer device (2) and the lamp (3) and a feedback arm (4-6) containing a feedback controller for acting on the lamp's electrical drive, for which purpose the feedback controller receives the actual primary circuit (2.1-2.3) current and a measure of the supply voltage (UB) for the transfer device. The feedback controller has a microcomputer (4) that receives the primary circuit actual current (IIST) and the measure of the supply voltage and defines a transfer device efficiency parameter. The microcomputer computes a demand current value (ISOLL) giving an optimal lamp drive based on the actual current, supply voltage and efficiency value.