DEVICE HAVING AN ELECTRICALLY HEATABLE HONEYCOMB BODY, AND METHOD FOR OPERATING THE HONEYCOMB BODY

摘要

The present invention relates to a device (1) for the treatment of exhaust gases in an exhaust system (2) of an internal combustion engine, in particular in a motor vehicle, having an electrically heatable honeycomb body (4) which is arranged in a casing tube (3) and through which an exhaust gas can flow, and to a method for operating such an electrically heatable honeycomb body (4) through which an exhaust gas can flow. The honeycomb body (4) has at least one current-conducting structure (5) with electric insulation (7) designed for voltages greater than 24 V, to which current-conducting structure a current-generating voltage (8) is applied in order to heat the honeycomb body (4). The method according to the invention is characterized in that the voltage (8) is a pulsed voltage. With the teaching according to the invention, it is possible for heating elements in the exhaust-gas flow to be powered using an on-board electrical system voltage of for example 48 V. In particular, a method is provided by means of which, even at operating voltages greater than 24 V, the generation of heat in the electrically heatable honeycomb body (4) can be kept in a desired range by adjustment of pulse width and/or repetition frequency of the pulsed voltage (8).