| 摘要 |
PROBLEM TO BE SOLVED: To more reliably actualize excellent ignitability by specifying at least one of a magnitude relationship between absolute values for a plus-side voltage and a minus-side voltage and a magnitude relationship between absolute values for a plus-side current and a minus-side current during charging AC power.SOLUTION: An ignition system 31 includes an ignition plug 1, a discharge power supply 41 for applying a voltage to a gap 28 of the ignition plug 1 to generate spark discharge, and an AC power supply 51 for charging AC power into spark generated by the spark discharge to generate AC plasma. In a period for charging the AC power, for at least one of a voltage applied to the gap 28 and a current flowing in the gap 28, lower one of the absolute value of the average value of plus-side peak values and the absolute value of the average value of minus-side peak values is 20% or more of higher one of both values. |
