Method for operating a drivetrain

A method of operating a drive-train of a motor vehicle, the drive-train comprising a drive aggregate having a hybrid drive unit with an internal combustion engine and an electric machine, an electrical energy accumulator that is chargable when the electric machine of the hybrid drive unit operates as a generator and is dischargable when the electric machine of the hybrid drive unit operates as a motor, a transmission connected between the hybrid drive unit and a drive output, and at least one auxiliary power takeoff on at least one of a transmission side and a drive aggregate side such that the at least one auxiliary power takeoff operable with variable energy demand within functional capability limits that depend on the at least one auxiliary power takeoff, depending on at least one of a current operating status of the hybrid drive unit, a current operating status of the electrical energy accumulator and a current operating status of the at least one auxiliary power takeoff, the method comprising the steps of:

• balancing energy for the drive train as a whole, via operation of an electric intermediate circuit, based upon an efficiency of each of the internal combustion engine, the electric machine, the electrical energy accumulator and the at least one auxiliary power takeoff, and a storage capacity and condition parameters of the energy accumulator and functional capability limits of the at least one auxiliary power takeoff such that the electric intermediate circuit at least one of:
• storing a portion of energy not required at the drive output in the electrical energy accumulator, and
• directing a portion of energy, not required at the drive output, to bypass the electrical energy accumulator and converting the portion of the energy, not required at the drive output, and storing the converted energy in an auxiliary power takeoff energy store to achieve an optimum overall efficiency of the drive-train, and
• the at least one auxiliary power takeoff being a cooling aggregate that cools a refrigeration chamber, and the energy not needed at the drive output bypassing the electrical energy accumulator and being used by the cooling aggregate for cooling down the refrigeration chamber to within admissible temperature limits so as to store the energy, not needed at the drive output, as thermal energy in the refrigeration chamber.

A method of operating a drive-train of a motor vehicle, the drive-train comprising a drive aggregate having a hybrid drive unit with an internal combustion engine and an electric machine, an electrical energy accumulator that is chargable when the electric machine of the hybrid drive unit operates as a generator and is dischargable when the electric machine of the hybrid drive unit operates as a motor, a transmission connected between the hybrid drive unit and a drive output, and at least one auxiliary power takeoff on at least one of a transmission side and a drive aggregate side such that the at least one auxiliary power takeoff operable with variable energy demand within functional capability limits that depend on the at least one auxiliary power takeoff, depending on at least one of a current operating status of the hybrid drive unit, a current operating status of the electrical energy accumulator and a current operating status of the at least one auxiliary power takeoff, the method comprising the steps of:

• balancing energy for the drive train as a whole, via operation of an electric intermediate circuit, based upon an efficiency of each of the internal combustion engine, the electric machine, the electrical energy accumulator and the at least one auxiliary power takeoff, and a storage capacity and condition parameters of the energy accumulator and functional capability limits of the at least one auxiliary power takeoff such that the electric intermediate circuit at least one of:
• storing a portion of energy not required at the drive output in the electrical energy accumulator, and
• directing a portion of energy, not required at the drive output, to bypass the electrical energy accumulator and converting the portion of the energy, not required at the drive output, and storing the converted energy in an auxiliary power takeoff energy store to achieve an optimum overall efficiency of the drive-train, and
• the at least one auxiliary power takeoff being a cooling fan that cools an internal combustion engine, and the energy not needed at the drive output bypassing the electrical energy accumulator and being used by the cooling fan for cooling the internal combustion engine to within admissible temperature limits so as to utilize the energy, not needed at the drive output, as thermal energy for cooling the internal combustion engine.

A method of operating a drive-train of a motor vehicle, the drive-train comprising a drive aggregate having a hybrid drive unit with an internal combustion engine and an electric machine, an electrical energy accumulator that is chargable when the electric machine of the hybrid drive unit operates as a generator and is dischargable when the electric machine of the hybrid drive unit operates as a motor, a transmission connected between the hybrid drive unit and a drive output, and at least one auxiliary power takeoff on at least one of a transmission side and a drive aggregate side such that the at least one auxiliary power takeoff operable with variable energy demand within functional capability limits that depend on the at least one auxiliary power takeoff, depending on at least one of a current operating status of the hybrid drive unit, a current operating status of the electrical energy accumulator and a current operating status of the at least one auxiliary power takeoff, the method comprising the steps of:

• balancing energy for the drive train as a whole, via operation of an electric intermediate circuit, based upon an efficiency of each of the internal combustion engine, the electric machine, the electrical energy accumulator and the at least one auxiliary power takeoff, and a storage capacity and condition parameters of the energy accumulator and functional capability limits of the at least one auxiliary power takeoff such that the electric intermediate circuit at least one of:
• storing a portion of energy not required at the drive output in the electrical energy accumulator, and
• directing a portion of energy, not required at the drive output, to bypass the electrical energy accumulator and converting the portion of the energy, not required at the drive output, and storing the converted energy in an auxiliary power takeoff energy store to achieve an optimum overall efficiency of the drive-train;
• and
• increasing a load operating point of the internal combustion engine based of an energy balance.

A method for operating a drive-train of a motor vehicle, the drive-train comprising a hybrid drive unit with an internal combustion engine and an electric machine, an electrical energy accumulator that is chargable when the electric machine operates as a generator and dischargable when the electric machine operates as a motor, a transmission that is connected between the hybrid drive unit and a drive output, and at least one auxiliary power takeoff connected to at least one of the transmission and the hybrid drive, the at least one auxiliary power takeoff is operated with a variable energy demand within functional capability limits that depend on the at least one auxiliary power takeoff, depending on a current operating status of at least one of the hybrid drive unit, the electrical energy accumulator and the at least one auxiliary power takeoff, the method comprising the steps of:

• balancing enemy for the drive train as a whole, via operation of an electric intermediate circuit, based upon at least one of an efficiency of the internal combustion engine, an efficiency of the electric machine, an efficiency of the electrical energy accumulator, an efficiency of the at least one auxiliary power takeoff, and storage capacity and condition parameters of the energy accumulator and functional capability limits of the at least one auxiliary power takeoff such that the electric intermediate circuit at least one of:
• storing a portion of energy that is not required at the drive output in the electrical energy accumulator, and
• directing a portion of energy that is not required at the drive output to bypass the electrical energy accumulator and converting and storing the portion of the energy that is not required at the drive output in an auxiliary power takeoff energy store;
• and
• the at least one auxiliary power takeoff being either a hydraulically or a pneumatically actuated auxiliary power takeoff, and the energy not needed at the drive output bypassing the electrical energy accumulator and being used to increase a working pressure to within admissible pressure limits in either a hydraulic reservoir or a pneumatic reservoir.