Combustion initiation system employing hard discharge ignition

A method of initiating combustion of fuel-air mixtures in an internal combustion engine using a capacitive discharge ignition system, comprising the steps of:

• (A) producing a supply of electrical power;
• (B) charging a capacitor with a quantity of electrical energy which is sufficient in magnitude to initiate combustion of said fuel-air mixture, using said electrical power produced in step (A);
• (C) forming an electrical discharge channel of alternating electrical current between the electrodes of an electrical discharge device having a pair of said electrodes;
• and
• (D) transferring at least approximately 80 percent of said stored quantity of electrical energy to said discharge channel within the first one-half cycle of said current.

A method of initiating combustion of fuel-air mixture in an internal combustion engine using a capacitive discharge system, comprising:

• subjecting each fuel-air mixture to a hard discharge electrical breakdown having a hardness factor .phi. equal to or less than approximately 0.5, where .phi. is defined by the equation ##EQU13## where t.sub.m is the time (in nanoseconds) at which the rate of rise of current flow in the system is substantially maximum,
• R.sub.m is the resistance in ohms of the electrical arc channel at t.sub.m,
• C is the capacitance in nanohenries of the system, and
• lg is the length in centimeters of the gap between which the arc occurs.