Patent attributes
A method for operating a supercharged internal combustion engine. Before a cold start of the engine, an electric drive device of an electrically assisted exhaust-gas turbocharger of the engine is activated such that fresh air is compressed by a compressor of the turbocharger and, in the process, is heated and is conveyed via an open overrun air recirculation valve arranged downstream of the compressor, through a short circuit back to a suction side of the compressor of the turbocharger. A proportion of the air that is heated by way of the short-circuit operation of the compressor is, downstream of the compressor and upstream of a closed throttle flap of the engine, conducted via a secondary air system into an exhaust manifold and from there via a wastegate of the turbocharger into the catalytic converters of an exhaust-gas aftertreatment device of the engine.