Plasma ignition system using photothyristors for internal combustion

Abstract

A plasma ignition system for an internal combustion engine, which comprises: (a) a low DC voltage power supply; (b) a DC-DC converter which converts a low DC voltage from the low DC voltage supply to the corresponding AC voltage and inverts the AC voltage to a high DC voltage; (c) a plurality of plasma ignition plugs each located within one of the cylinders; (d) a plurality of first capacitors each for changing the high DC voltage received from the DC-DC converter; (e) a plurality of photosensitive switching elements each connected between each corresponding first capacitor and ground and which turns on to apply the plasma ignition energy charged within the corresponding first capacitor to the corresponding plasma ignition plug at a predetermined timing; (f) a plurality of voltage-boosting transformers each having a common terminal of primary and secondary windings connected to one terminal of each corresponding plasma ignition energy capacitor and another terminal of the primary winding connected to the corresponding plasma ignition plug for boosting the voltage across the corresponding first capacitor to a still higher voltage at the secondary winding thereof depending on the winding ratio therebetween; (g) a plurality of second capacitors connected between another terminal of the secondary winding of each voltage-boosting transformer and ground so as to form an oscillation circuit together with the primary winding of the corresponding transformer;