Ignition system and method for checking electrodes of a spark plug of an internal combustion engine

An ignition system for an internal combustion engine with externally provided ignition, the ignition system comprising:

• a spark gap;
• a primary voltage generator;
• and
• an evaluation unit, wherein the evaluation unit is configured to:
• use the primary voltage generator to generate a spark at the spark gap in an operating state without ignition of an ignitable mixture in the combustion chamber;
• ascertain a parameter or characteristic function representing at least one of the spark current, the spark voltage, and the spark duration;
• compare the parameter or the characteristic function to a reference;
• adapt at least one of an amount and a duration of voltage at the spark gap for at least one of generating and maintaining a further ignition spark for ignition of the mixture as a function of a difference between the parameter or the characteristic function and the reference, determined as a result of the comparison;
• and
• generate and maintain the further ignition spark at the spark gap for the ignition of the mixture, using the adapted voltage;
• wherein the generation of the further ignition spark is performed with a primary voltage generator, and
• wherein the further ignition spark is maintained using a step-up chopper.

A method for operating an ignition system for generating a spark at a spark gap in a combustion chamber of an internal combustion engine having externally supplied ignition, the method comprising:

• generating the spark at the spark gap using a primary voltage generator;
• ascertaining a parameter;
• comparing the parameter to a reference;
• adapting an energy, as a function of a difference between the parameter and the reference, for at least one of:
• (i) a voltage buildup for the spark generation, and (ii) maintaining an ignition spark for ignition of an ignitable mixture in the combustion chamber, as a function of a difference between the parameter and the reference, wherein the adapting is for a future ignition process;
• wherein, in the generating step, the spark at the spark gap is generated in an operating state without ignition of the ignitable mixture in the combustion chamber and is maintained by a step-up chopper so that the parameter correlates with an electrode state or electrode gap at the spark gap;
• wherein, in the ascertaining step, at least one of a spark current and the spark voltage is ascertained as the parameter;
• and
• wherein a value of the reference is a first threshold value which is specified based on the electrode gap at an initial operation of the ignition system and while taking a maximally permitted wear into account;
• and wherein the method further comprises using the adapted energy in the future ignition process to at least one of generate and maintain a further ignition spark at the spark gap for the ignition of the mixture.