An ignition system includes: a step-up transformer having a primary side and a secondary side; an electrical energy source configured to be selectably connected to the primary side; a spark gap which is configured to guide a current transferred by the step-up transformer to the secondary side. The step-up transformer has a bypass for transferring electrical energy from the electrical energy source to the secondary side. The ignition system is configured to couple electrical energy in series or in parallel to the secondary side of the high voltage generator for the purpose of maintaining an ignition spark as an electrical voltage in the form of a controlled pulse sequence, e.g., within the kilo-hertz range.