High-frequency assisted ignition for modern gasoline engines

Spark ignition systems are used in many applications. One important application is the ignition of fuel-air-mixtures inside the cylinder of an Otto engine. Modern conventional ignition systems consist of an ignition coil and a spark plug. The ignition coil generates a high voltage impulse which causes a spark plasma between the electrodes of the spark plug. Because of the short burning duration of the spark and the limited stored energy of the ignition coil, the available ignition energy is limited, too. But the combustion of lean and diluted fuel-air-mixtures or renewable fuels requires a high ignition energy.

In cooperation with the Institute of Electronic Circuits, the Institute for Combustion Engines and an industry partner (the Rosenberger Hochfrequenztechnik GmbH & Co. KG) a high frequency enhanced ignition system was invented. The ignition system makes it possible to control the power input and the burning duration of the plasma between the electrodes of the spark plug. Therefore, it is able to ignite critical fuel-air-mixtures. The plasma characterization validates the results from several investigations with modern serial Otto engines. To complete the investigations the electrode erosion of the spark plug is investigated and minimized, too.