Plasma ignition and combustion assist system for gas turbine engines

A driver unit for use with an igniter having an igniter body with an inner wall housing a centrally positioned electrode in spaced apart relationship with the inner wall and a combustor of a gas turbine engine, the plasma igniter positioned inside the combustor, the driver unit in electrical communication with the electrode, the driver unit comprising:

• an input power controller;
• a voltage oscillator communicating with the input power controller;
• a transformer communicating with the voltage oscillator and the input power controller;
• an on-off switch communicating with the input power controller;
• and
• a power source providing at least one of alternating and direct current input to the driver unit;
• wherein the driver unit provides an output of voltage and current to the electrode;
• wherein the driver unit is grounded to an engine or to a combustor;
• wherein the input power is regulated, filtered and modulated by the input power controller;
• wherein the voltage oscillator creates an electrical output waveform at a desired frequency and level;
• wherein the transformer transforms the electrical output waveform generated by the voltage oscillator and generates a voltage level and voltage rate of change sufficient to create an electric arc;
• and
• wherein the igniter is a plasma igniter comprising:
• an igniter body having a lead end and an opposed outlet end, with an inner wall defining a chamber between the lead end and the outlet end;
• wherein the outlet end of the igniter body is an open end of the chamber positioned near the primary burn region of the combustor;
• wherein the igniter body is electrically grounded to either the combustor or directly to the igniter drive electronics by an insulated wire;
• an electrode having a proximal end and at least one of a conical and cylindrical distal end housed centrally inside the chamber and electrically isolated from the inner wall of the igniter body;
• wherein the distal end is further comprised of a terminal end positioned towards the outlet end of the igniter body;
• wherein the distal end is further formed with at least one corner having a corner radius ranging from zero to 0.15 inches;
• an arc gap of a predetermined distance measured from the corner to the inner wall of the igniter body;
• wherein the arc gap is a distance selected from the group of distances including a smallest distance from the corner of the electrode to the inner wall of the igniter body and a smallest distance from the corner to the inner wall at the outlet end of the igniter body;
• an approximately annular air gap between the electrode and the inner wall;
• an electrical lead having an electrode end and a power end, the electrode end affixed inside the electrode at the proximal end and the power end connected to the driver unit, whereby an electrical current is supplied to the electrical lead and electrode by the driver unit;
• and
• at least one protrusion on the distal end;
• wherein the corner is an outermost surface of the protrusion;
• and
• a largest circumference measurement of the distal end of the electrode includes the protrusion.