Method for operating a vehicle

Abstract

A method for operating a vehicle having: an internal combustion engine for driving the vehicle; at least one emission-relevant load; at least one electrical-system battery; and at least one vehicle battery, in which method prior to the start-up of the vehicle, the at least one vehicle battery is charged with electrical energy from the at least one electrical-system battery and, prior to and/or during the start-up of the internal combustion engine, the at least one emission-relevant load is charged with this electrical energy from the vehicle battery.

Claims

1. A method for operating a vehicle comprising an internal combustion engine for driving the vehicle, at least one emission-relevant load, at least one electrical-system battery, and at least one vehicle battery, the method comprising: determining a quantity of electrical energy which was required to start the at least one emission-relevant load during a current or previous n-th journey, after determining that the at least one emission-relevant load is to receive a transfer, and prior to the emission-relevant load being supplied with the quantity of electrical energy, transferring the quantity of electrical energy from the at least one electrical-system battery to the at least one vehicle battery prior to an initial start of the vehicle for an upcoming n+1-th journey, and energizing the at least one emission-relevant load using the vehicle battery prior to startup of the internal combustion engine for the upcoming n+1-th journey, wherein the at least one vehicle battery has an electrical voltage which is higher than that of the at least one electrical-system battery.

2. The method according to claim 1, wherein energizing the at least one emission-relevant load occurs at startup of the internal combustion engine for the upcoming n+1-th journey.

3. The method according to claim 1, wherein energizing the at least one emission-relevant load comprises electrical heating.

4. The method according to claim 1, wherein transferring the quantity of electrical energy occurs once the vehicle has been parked after the current or previous n-th journey.

5. The method according to claim 1, wherein the at least one electrical-system battery has an electrical voltage of 12 V and the at least one vehicle battery has an electrical voltage of 48 V.

6. The method according to claim 1, wherein the at least one emission-relevant load serves as an exhaust gas purification device.

7. The method according to claim 1, wherein energizing the at least one emission-relevant load constitutes startup of the at least one emission-relevant load.

8. The method according to claim 1, wherein the at least one emission-relevant load operates at the electrical voltage of the at least one vehicle battery.

9. The method according to claim 1, wherein the at least one electrical-system battery is a starter battery.

10. The method according to claim 1, wherein the at least one electrical-system battery is a lead-acid battery.

11. The method according to claim 10, wherein the at least one vehicle battery is a lithium-ion battery.

12. The method according to claim 1, wherein the vehicle battery further supplies energy to the at least one emission-relevant load during active driving of the vehicle.

13. The method according to claim 12, wherein, in an instance where the vehicle battery further supplies energy to the at least one emission-relevant load during the active driving of the vehicle, no step-up operation is performed during the active driving.

14. The method according to claim 1, wherein determining the quantity of electrical energy is performed during a current n-th journey or after concluding a previous n-th journey, and wherein transferring the quantity of electrical energy from the at least one electrical-system battery to the at least one vehicle battery is performed after concluding the current or previous n-th journey by parking and switching off the vehicle and prior to subsequently switching on the vehicle.

15. The method according to claim 14, further comprising a step of: determining that the vehicle has been parked and switched off, wherein determining that the at least one emission-relevant load is to receive the transfer is based on determining that the vehicle has been parked and switched off.

16. The method according to claim 1, wherein at least the at least one electrical-system battery has a control unit electrically connected thereto and supplied thereby; and wherein determining the quantity of electrical energy required to start the at least one emission-relevant load is performed by determining, with the control unit, the quantity of electrical energy supplied by the at least one vehicle battery to the at least one emission-relevant load.

17. The method according to claim 16, further comprising determining whether to change the quantity of electrical energy based on at least one sensed ambient condition; wherein energization of the at least one emission-relevant load uses either the quantity of electrical energy or an adjustment to the quantity of electrical energy based on the at least one sensed ambient condition.

18. A system for operating a vehicle, the vehicle comprising an internal combustion engine for driving, at least one emission-relevant load, at least one electrical-system battery, and at least one vehicle battery, the system comprising at least one control unit which is configured to: determine a quantity of electrical energy which was required to start the at least one emission-relevant load during a current or previous n-th journey, after determining that the at least one emission-relevant load is to receive a transfer, and prior to the emission-relevant load being supplied with the quantity of electrical energy, command transfer of the quantity of electrical energy from the at least one electrical-system battery to the at least one vehicle battery prior to an initial start of the vehicle for an upcoming n+1-th journey, and command energization the at least one emission-relevant load using the vehicle battery prior to startup of the internal combustion engine for the upcoming n+1-th journey, wherein the at least one vehicle battery has an electrical voltage which is higher than that of the at least one electrical-system battery.

19. The system according to claim 18, wherein the at least one emission-relevant load operates at the electrical voltage of the at least one vehicle battery.

Description

BRIEF DESCRIPTION OF THE FIGURE(S)

(1) The invention is illustrated schematically by means of embodiments in the drawing and is described schematically and in detail with reference to the drawing.

(2) FIG. 1 shows in schematic representation an example of a vehicle for which an embodiment of the method according to the invention is carried out.

DETAILED DESCRIPTION

(3) FIG. 1 shows in schematic representation an example of a vehicle 2, in the embodiment of the method according to the invention in different operating conditions A, B and C. This vehicle 2 comprises as components an electric machine 4, a control unit 6, an electrical-system battery 8 as a first battery with a voltage of 12 volts, a vehicle battery 10 as a second battery with a voltage of 48 volts, an internal combustion engine 12 and an exhaust gas purification device 14 as an example of an emission-relevant load of the vehicle 2.

(4) It is further provided that the electric machine 4 and the internal combustion engine 12 are both provided as drive units of the vehicle 2, wherein it is possible to drive or move the vehicle 2 either with the electric machine 4 or with the internal combustion engine 12. Therefore, the vehicle 2 shown here is also designed and/or to be designated as a hybrid vehicle.

(5) In the first operating condition A provided here, it is a matter of an nth journey of the vehicle 2, where n is an integer, wherein it is provided here that functions of the vehicle 2 during the journey are also controlled by the control unit 6 independently of the embodiment of the method presented here.

(6) During the nth travel of the vehicle 2, which is configured here as a hybrid vehicle, in the first operating condition A, it is possible, on the one hand, for the vehicle 2 to be driven by the internal combustion engine 12. In this case, a fuel, for example a hydrocarbon compound, is burned within the combustion engine 12. In the process, the combustion engine 12 converts chemical energy from the fuel into mechanical energy and transfers it to wheels of the vehicle 2. When the hydrocarbon compound is burned, exhaust gases are produced, but these are purified by the exhaust gas device 14.

(7) On the other hand, the vehicle 2 can alternatively be driven by the electric machine 4, in which case electrical energy stored in the vehicle battery 10 is provided to the electric machine 4 for this purpose (arrow 16). This electrical energy is converted by the electric machine 4, if it is operated as an electric motor, into mechanical energy and transferred to wheels of the vehicle 2.

(8) If the vehicle 2 is driven by the internal combustion engine 12 during travel, however, it is necessary that the exhaust gas device 14 has at least one operating temperature intended for this purpose in order to clean the exhaust gases.

(9) For this purpose, in the presented embodiment of the method, it is provided that the exhaust device 14 is set and/or prepared for a future subsequent n+1th journey. Such preparation and or adjustment is carried out here after the nth journey, when the electric machine 4, the internal combustion engine 14 and the vehicle 2 are switched off. Thereby, in the context of the method, a further operating condition B is provided after the vehicle 2 has been parked. In this case, electrical energy is transferred from the electrical-system battery 8 to the vehicle battery 10, and this electrical energy remains stored in the vehicle battery 10 during a standstill of the vehicle in the vehicle battery 10.

(10) In the embodiment of the method, in a third operating condition C, it is provided that the vehicle 2 is restarted after the standstill that follows the parking of the vehicle 2 in the operating condition B. In this case, the electrical energy that has previously been transferred from the electrical-system battery 8 to the vehicle battery 10 continues to be transferred from the vehicle battery 10 to the exhaust gas purification device 14 when the vehicle 2 is started and before a start, for example an initial start, of the internal combustion engine 12 (arrow 20). The exhaust gas purification device 14 is warmed up or heated with this electrical energy, whereby the exhaust gas purification device 14 is ramped up and reaches at least the operating temperature intended for the exhaust gas purification device 14 even before a start of the internal combustion engine 12. Thus, the vehicle 2 and the exhaust gas purification device 14 are prepared for the subsequent further n+1th journey (renewed operating condition A), which follows the start of the vehicle 2, the ramping up of the exhaust gas purification device 20 and the start of the internal combustion engine 10 (operating condition A). Here, it is provided that the control unit 6 or a corresponding control unit as part of an embodiment of a system according to the invention is designed to control the method.

REFERENCE NUMBERS

(11) A,B,C Operating condition 2 Vehicle 4 Electric machine 6 Control unit 8 Electrical-system battery 10 Vehicle battery 12 Combustion engine 14 Exhaust gas purification device 16, 18, 20 Arrow