| 摘要 |
PURPOSE:To generate high voltage and to start an electric discharge lamp without a heavy load on a switching element by making a saturable reactor connected to the electric discharge lamp in series non-saturated at the time of starting operation and saturable at the time of lighting operation. CONSTITUTION:A saturable reactor L2 is in a non-saturated condition when an electric discharge lamp 3 is started. An inverter circuit 2 is operated in the vicinity of a resonance frequency determined by an inductor L2 and a capacitor C, while a resonance condition is induced in a closed circuit, and high voltage is generated on both terminals of the electric discharge lamp 3. When a load side is seen from the circuit 2, the reactor LS having high inductance value while the reactor LS is in a non-saturated condition and an inductor L1, and a parallel resonance circuit consisting of the capacitor C and the inductor L2, are connected in series. A large current flows in the electric discharge lamp 3 in a lighted condition, and the reactor LS becomes saturated, while the inductance value is reduced. The output current of the circuit 2 is reduced at the time of starting, and the electric discharge lamp can be started without a heavy load on the switching element. |
