Inverter for the supply of discharge lamps with heated electrodes, with resonant circuit.

摘要

An inverter for the supply of one or more discharge lamps (11; 111A, 111B) with heated electrodes (13, 15), comprises: a load circuit with a series resonant circuit (17, 19, 21, 117A, 117B; 119; 121) and at least one lamp (11, 111A, 111B), two controllable switches (7, 9; 107, 109) and a control circuit (25) for the said switches, causing the said switches to conduct alternately. A normally isolated dissipative component (33; 133), which is connected, when the voltage across the load circuit exceeds a given value, to the load circuit, thus modifying its figure of merit to limit the maximum voltage without varying the resonant frequency of the load circuit.