Patent ID: 9002551
Filing Date: 2015-04-07
Classification: B60L,B60W,Y02T

Abstract:
1. A method for operating a hybrid vehicle, the hybrid vehicle comprising a combustion engine, an electric motor, a drive train selectively coupled to the electric motor or the combustion engine, and a control device, the method comprising the following steps, wherein said steps are performed by said control device: automatically determining an operating mode of the hybrid vehicle, the operating mode specifying whether (a) the combustion engine, (b) the electric motor, or (c) the combustion engine and the electric motor is selected as a drive mechanism of the hybrid vehicle, wherein the operating mode is determined as a function of a setpoint torque and an operating state of the hybrid vehicle, and being selected at least such that the drive train, including the selected drive mechanism, is operating at a maximum efficiency based on at least one characteristic data field of the operating state of the hybrid vehicle, wherein the operating state is dependent upon at least one parameter selected from the group consisting of a state of charge of a battery of the hybrid vehicle, a temperature of the battery, a friction of the combustion engine, a temperature of the combustion engine, a friction of the drive train, a temperature of the drive train, an energy requirement of an electrical system of the hybrid vehicle, and a driving speed of the hybrid vehicle; automatically coupling at least one of (a) the combustion engine and (b) the electric motor to the drive train to operate the hybrid vehicle depending on the determined operating mode; determining a first torque limit value and a second torque limit value, each as a function of the operating state of the hybrid vehicle; using only the electric motor as the drive mechanism when a setpoint torque is less than or equal to the first torque limit value; using at least the combustion engine as the drive mechanism when the setpoint torque is higher than the first torque limit value; and using the combustion engine and the electric motor as the drive mechanism when the setpoint torque is higher than the second torque limit value.