DEVICE FOR RECOVERING ELECTRIC ENERGY FROM THE EXHAUST HEAT OF AN INTERNAL COMBUSTION ENGINE IN A MOTOR VEHICLE AND METHOD FOR RECOVERING ELECTRIC ENERGY FROM THE EXHAUST HEAT OF AN INTERNAL COMBUSTION ENGINE IN A MOTOR VEHICLE

摘要

The invention relates to a device for recovering electric energy from the exhaust heat of an internal combustion engine in a motor vehicle. Said device comprises a heat exchanger, through the primary side of which exhaust gas of the internal combustion engine flows and through the secondary side of which heat exchanger fluid flows, said fluid being brought to a first high temperature and/or pressure level in the heat exchanger during the operation of the internal combustion engine. The device has at least one Laval nozzle with an entry and an exit, the entry being connected to an outlet of the heat exchanger on the secondary side and the exit being oriented towards the impellers of an impulse turbine, said nozzle having such dimensions that it supplies steam to the impulse turbine at a lower second temperature and/or pressure level than the first high temperature and/or pressure level and at a higher flow rate. In addition, the device has an electric generator with a rotor that is coupled to the impulse turbine and that is caused to rotate by the latter and a stator comprising at least one stator winding, from which electric power can be tapped. The device also has a condenser, designed to condense steam that has been used in the impulse turbine. The liquid obtained from said steam by condensation can be fed into an inlet of the first heat exchanger on the secondary side.