Method for operating an ignition device for an internal combustion engine, and ignition device for an internal combustion engine for carrying out the method

Abstract

The invention relates to a method for operating an ignition device for an internal combustion engine, which ignition device is formed with an ignition coil (ZS) which is configured as a transformer, a spark plug (ZK) which is connected to the secondary winding of the ignition coil (ZS), an actuable switching element (IGBT) which is connected in series to the primary winding of the ignition coil (ZS), and a control unit (SE) which is connected to the control input of the switching element (IGBT), wherein the control unit (SE) provides an adjustable supply voltage (Vsupply) for the ignition coil (ZS) and an actuating signal (IGBT_Control) for the switching element (IGBT) as a function of the currents (I_Prim, I_Sec) through the primary and the secondary windings of the ignition coil (ZS) and the voltage between the connecting point of the primary winding of the ignition coil (ZS); to the switching element (IGBT) and the negative terminal of the supply voltage (GND), as a result of which firstly operation of the spark plug (ZK) by way of alternating current is possible and secondly regulation of said current is possible, which leads to more reliable ignition with a lower wear of the spark plugs.

Description

Background technique [0001] For many years, series ignition systems, which are now constructed as gasoline engines, operate on the simple and reliable principle of coil discharge, that is to say, the ignition coils, which are correspondingly designed as transformers, draw from the on-board supply voltage on the primary side according to their inductance Charge partially up to its saturation range. At the moment of ignition, charging is interrupted by means of an electronic circuit, for example by ignition of an IGBT (Insulated Gate Bipolar Transistor). A voltage of, for example, 5 kV to 35 kV is thus formed on the secondary side, which voltage leads to arcing in the spark gap of the ignition plug in the combustion chamber of the internal combustion engine. Next, the energy stored in the coil is released in the ignition plasma. [0002] Consumption savings and emissions have to be achieved during the development of propulsion engines, which have consistently led to an increas...

AI Technical Summary

Problems solved by technology

[0016] Although ignition with such an alternating voltage can solve the problems of combustion technology, it is only suitable for high-end vehicles for cost reasons

Therefore, hitherto, the wear of the ignition plugs associated with the increased ignition energy had to be accepted, or the ignition-critical operating states could not be achieved on serial engines

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