Method for operating an electric drive system

Abstract

The invention relates to a method for operating an electric drive system of a motor vehicle with a backup battery and a fuel cell for providing electric drive power. Here, route data is determined and then, based on this route data, consumption data is forecast. The invention is characterized in that, in order to optimize the operation of the fuel cell based on the forecast consumption data, a total energy demand for the route is forecast, after which a mean fuel cell power is determined which is required together with the energy stored at the starting time of the route in the backup battery to determine the total energy demand over a constant power trajectory for the fuel cell. This is followed by a check as to whether limit values of the backup battery are violated when driving along the route with the power trajectory: if no limit value is violated, the fuel cell is operated with the specified power trajectory; if a limit value is violated, the power of the fuel cell is changed in the area where the limit value is violated and then adjusted to achieve the mean fuel cell power again over the entire route, whereby a new power trajectory is defined. The check is then run through again with the new power trajectory until a power trajectory has been determined without violating the limit values of the backup battery, according to which the fuel cell is then operated.