Patent ID: 8020651
Filing Date: 2011-09-20
Classification: B60K,B60L,B60W,Y02T

Abstract:
1. A method for controlling an operation of a motor vehicle with a hybrid drive unit, which comprises an internal combustion engine and at least one electric machine coupled to a drive train of the motor vehicle, wherein the at least one electric machine is selectively operated in a motor operation mode and a generator operation mode, wherein, when the electric machine is operated in the motor operation mode, the electric machine powers the motor vehicle either alone or in addition to the internal combustion engine, and, when the electric machine is operated in the generator operation mode, the electric machine charges an energy store and/or powers a vehicle electrical system of the motor vehicle, wherein, when the electric machine is operated in the generator operation mode, depending on maintaining predetermined boundary conditions, the electric machine operates in an alternating generator mode and a continuous generator mode, wherein, when the electric machine is operated in the alternating generator mode, the electric machine is operated in a manner in which first and second intervals are alternated, wherein (a) in a first interval, the electric machine is operated with a first, high electric power output which is greater than an actual power consumption of the vehicle electrical system, and (b) in the second interval, the electric machine is switched off, wherein an efficiency accounting is performed to determine an efficiency advantage of the alternating generator mode in comparison to the continuous generator mode, wherein the efficiency accounting takes into consideration a shift in a load level of the internal combustion engine, and further wherein the alternating generator mode of the electric machine is selected if the efficiency advantage of the alternating generator mode, determined by the efficiency accounting, reaches or exceeds a predetermined threshold value.