METHOD OF HEATING POWERTRAIN, COMPUTER PROGRAM, COMPUTER-READABLE MEDIUM, CONTROL ARRANGEMENT, POWERTRAIN, AND VEHICLE

Abstract

A method of heating a powertrain of a vehicle is disclosed, wherein the powertrain comprises an electric machine configured to provide motive power to the vehicle. The method comprises the step of passing an electric current through the electric machine to rotate a rotor of the electric machine while ensuring stand still of the vehicle. The present disclosure further relates to a computer program, a computer-readable medium, a control arrangement, a powertrain for a vehicle, and a vehicle comprising a powertrain.

Claims

1. A method of heating a powertrain of a vehicle, wherein the powertrain comprises an electric machine configured to provide motive power to the vehicle, and wherein the method comprises the step of: passing an electric current through the electric machine to rotate a rotor of the electric machine while ensuring stand still of the vehicle.

2. The method according to claim 1, wherein the powertrain comprises a transmission configured to transmit power between the electric machine and one or more wheels of the vehicle, and wherein the method further comprises the steps of: controlling the powertrain to a state in which at least a portion of the transmission is disconnected from the one or more wheels; and rotating the portion of the transmission using the rotor.

3. The method according to claim 1, further comprising the separate step of: passing an electric current through the electric machine in a manner ensuring stand still of the rotor.

4. The method according to claim 3, wherein the step of passing the electric current through the electric machine in a manner ensuring stand still of the rotor is performed prior to the step of passing the electric current through the electric machine to rotate the rotor.

5. The method according to claim 3, or wherein the method comprises the step of: switching back and forth between a first heating mode in which the electric current is passed through the electric machine in a manner ensuring stand still of the rotor and a second heating mode in which the electric current is passed through the electric machine to rotate the rotor.

6. The method according to claim 1, wherein the method further comprises the steps of: inputting current temperature data representative of a current ambient temperature and/or a current temperature of a portion of the powertrain; and controlling a duration of the passing of the electric current through the electric machine based on the inputted current temperature data.

7. The method according to claim 1, wherein the powertrain comprises a propulsion battery, and wherein the method further comprises the step of: heating the propulsion battery using heat generated by the passing of the electric current through the electric machine.

8. The method according to claim 1, wherein the vehicle comprises an occupant compartment, and wherein the method further comprises the step of: heating the occupant compartment using heat generated by the passing of the electric current through the electric machine.

9. A computer program comprising computer program code stored on a non-transitory computer-readable medium, said computer program product used for heating a powertrain of a vehicle, wherein the powertrain comprises an electric machine configured to provide motive power to the vehicle, said computer program code comprising computer instructions to cause one or more control units to perform the following operation: passing an electric current through the electric machine to rotate a rotor of the electric machine while ensuring stand still of the vehicle.

10. (canceled)

11. A control arrangement for a powertrain of a vehicle, wherein the powertrain comprises an electric machine configured to provide motive power to the vehicle, and wherein the control arrangement is configured to: pass an electric current through the electric machine to rotate a rotor of the electric machine while ensuring stand still of the vehicle.

12. A powertrain for a vehicle, wherein the powertrain comprises: an electric machine configured to provide motive power to the vehicle; and a control arrangement configured to pass an electric current through the electric machine to rotate a rotor of the electric machine while ensuring stand still of the vehicle.

13. A vehicle comprising a powertrain comprising an electric machine configured to provide motive power to the vehicle; and a control arrangement configured to pass an electric current through the electric machine to rotate a rotor of the electric machine while ensuring stand still of the vehicle.

14. The control arrangement according to claim 11, wherein the powertrain comprises a transmission configured to transmit power between the electric machine and one or more wheels of the vehicle, and wherein the control arranged is further configured to: control the powertrain to a state in which at least a portion of the transmission is disconnected from the one or more wheels; and rotate the portion of the transmission using the rotor.

15. The control arrangement according to claim 11, wherein the control arranged is further configured to: pass an electric current through the electric machine in a manner ensuring stand still of the rotor.

16. The control arrangement according to claim 15, wherein the passing of electric current through the electric machine in a manner ensuring stand still of the rotor is performed prior to the passing the electric current through the electric machine to rotate the rotor.

17. The control arrangement according to claim 15, wherein the control arranged is further configured to: switch back and forth between a first heating mode in which the electric current is passed through the electric machine in a manner ensuring stand still of the rotor and a second heating mode in which the electric current is passed through the electric machine to rotate the rotor.

18. The control arrangement according to claim 11, wherein the control arranged is further configured to: input current temperature data representative of a current ambient temperature and/or a current temperature of a portion of the powertrain; and control a duration of the passing of the electric current through the electric machine based on the inputted current temperature data.

19. The control arrangement according to claim 11, wherein the powertrain comprises a propulsion battery, and wherein the control arranged is further configured to: heat the propulsion battery using heat generated by the passing of the electric current through the electric machine.

20. The control arrangement according to claim 11, wherein the vehicle comprises an occupant compartment, and wherein the control arranged is further configured to: heat the occupant compartment using heat generated by the passing of the electric current through the electric machine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Various aspects of the invention, including its particular features and advantages, will be readily understood from the example embodiments discussed in the following detailed description and the accompanying drawings, in which:

[0076] FIG. 1 illustrates a vehicle according to some embodiments,

[0077] FIG. 2 schematically illustrates a powertrain of the vehicle illustrated in FIG. 1,

[0078] FIG. 3 illustrates a method of heating a powertrain of a vehicle, and

[0079] FIG. 4 illustrates computer-readable medium according to some embodiments.

DETAILED DESCRIPTION OF THE INVENTION

[0080] Aspects of the present invention will now be described more fully. Like numbers refer to like elements throughout. Well-known functions or constructions will not necessarily be described in detail for brevity and/or clarity.

[0081] FIG. 1 illustrates a vehicle 3 according to some embodiments. According to the illustrated embodiments, the vehicle 3 is a truck, i.e. a heavy vehicle. According to further embodiments, the vehicle 3, as referred to herein, may be another type of manned or unmanned vehicle for land based propulsion such as a lorry, a bus, a construction vehicle, a tractor, a car, or the like.

[0082] The vehicle 3 comprises a powertrain 1. The powertrain 1 is configured to provide motive power to the vehicle 3 via wheels 9 of the vehicle 3. The powertrain 1 is an at least partially electric powertrain, as is further explained herein. In FIG. 1, the vehicle 3 is illustrated as positioned onto a surface 10.

[0083] FIG. 2 schematically illustrates the powertrain 1 of the vehicle 3 illustrated in FIG. 1. Below, simultaneous reference is made to FIG. 1 and FIG. 2, if not indicated otherwise. The powertrain 1 comprises an electric machine 5. The electric machine 5 is configured to provide motive power to the vehicle 3 via wheels 9 of the vehicle 3. The electric machine 5 may also be referred to as an electric propulsion motor, an electric motor, or the like. According to the illustrated embodiments, the powertrain 1 is a pure electric powertrain and comprise no internal combustion engine. According to further embodiments, the powertrain 1, as referred to herein, may be a so called hybrid electric powertrain comprising an internal combustion engine in addition to the electric machine 5 for providing motive power to the vehicle 3. In FIG. 2, the powertrain 1 is illustrated as comprising one electric machine 5. However, the powertrain 1 may comprise more than one electric machine 5. According to the illustrated embodiments, the powertrain 1 comprises a transmission 7. The transmission 7 is configured to transmit power between the electric machine 5 and one or more wheels 9 of the vehicle 3.

[0084] The powertrain 1 comprises a propulsion battery 17. The propulsion battery 17 is configured to supply electricity to the electric machine 5 by an amount controlled by a power module 21. The power module 21 may comprise power electronics. The propulsion battery 17 may comprise a number of battery cells, such as lithium-ion battery cells, lithium polymer batteries cells, or nickel-metal hydride battery cells. The electric machine 5 comprises a rotor 6 and a stator 4. The electric machine 5 is capable of converting electrical energy into mechanical energy in the form of rotation of the rotor 6. Moreover, the electric machine 5 may be capable of converting mechanical energy in the form of rotation of the rotor 6 into electrical energy which for example can be stored in the propulsion battery 17. In this manner the electric machine 5 may provide regenerative braking of the vehicle 3.

[0085] One of the stator 4 and the rotor 6 may comprise a number of permanent magnets and the other of the stator 4 and the rotor 6 may comprise wire windings. An alternating electric current passed through the wire windings by the power module 21 causes a torque to be applied to the rotor 6 due to the magnetic interaction between the wire windings and the permanent magnets. During operation of the powertrain 1, the electric current passed through the wire windings is alternated in a manner following the rotation of the rotor 6. In this manner, a continuous torque can be applied to the rotor 6 during rotation thereof.

[0086] The powertrain 1 further comprises a charging module 31. The charging module 31 is connectable to an external power source 33 to charge the propulsion battery 17 using electricity from the external power source 33. The external power source may be connected to an electric power grid. The charging module 31 may comprise battery charging electronics. The charging module 31 may also be referred to as a battery charging module, a battery charger, or the like.

[0087] The powertrain 1 comprises a control unit 21. The control unit 21 is operably connected to power module 21. The control unit 21 and the power module 21 are together herein referred to as a control arrangement 21, 21. In FIG. 2, the control unit 21 and the power module 21 are illustrated as separate units. However, according to further embodiments, the control unit 21 and the power module 21 may be combined in one unit or may be comprised in a number of separate units, wherein the number is higher than two.

[0088] According to the illustrated embodiments, the transmission 7 comprises a gearbox capable of providing different gear ratios between the rotor 6 and wheels 9 of the vehicle 3. The control arrangement 21, 21 is operably connected to a gear selector 41 of the transmission 7 to perform gear changes of the transmission 7. According to the illustrated embodiments, the transmission 7 comprises a neutral state in which the rotor 6 of the electric machine 5 is rotationally disconnected from wheels 9 of the vehicle 3. Thus, when the transmission 7 is in the neutral state, the rotor 6 of the electric machine 5 is free to rotate even when the wheels 9 of the vehicle 3 are at stand still. According to further embodiments, the transmission 7 may comprise a fix gear ratio between the rotor 6 of the electric machine 5 and wheels 9 of the vehicle 3. Also in such embodiments, the transmission 7 may comprise a neutral state in which the rotor 6 of the electric machine 5 is rotationally disconnected from wheels 9 of the vehicle 3.

[0089] Moreover, according to the illustrated embodiments, the powertrain 1 is illustrated as comprising a coupling 43 between the transmission 7 and the wheels 9. The coupling 43 is controllable by the control arrangement 21, 21 between an engaged state, in which the coupling 43 connects the transmission 7 to the wheels 9, and a disconnected state, in which the coupling 43 disconnects the transmission 7 from the wheels 9. The coupling 43 may comprise a dog-clutch, a friction clutch, or the like. Gears and shafts of the transmission 7 may be free to rotate when the coupling 43 is in the disengaged state also when the wheels 9 of the vehicle 3 are at stand still. The powertrain 1 may comprise one of a transmission 7 controllable to a neutral state, as explained above, or a coupling 43 as described herein. As an alternative, or in addition, the powertrain 1 may comprise another type of arrangement capable of disconnecting the rotor 6 of the electric machine 5 from wheels 9 of the vehicle 3.

[0090] According to the illustrated embodiments, the powertrain 1 comprises a lubricant circuit 13. The lubricant circuit 13 comprises a lubricant pump 15 configured to pump lubricant through the lubricant circuit 13 to lubricate portions of the powertrain 1, such as gears, shafts, and bearings of the powertrain 1. According to the illustrated embodiments, the lubricant circuit 13 is illustrated as being configured to lubricate portions of the transmission 7. However, the lubricant circuit 13 may also be configured to lubricate further portions of the powertrain 1, such as portions of the electric machine 5 and the like. The lubricant pump 15 may be driven via a shaft connected to an input shaft of the transmission 7 such that operation of the lubricant pump 15 is ensured when the input shaft of the transmission 7 is rotating. As an alternative, the lubricant pump 15 may be driven by a separate driving unit, such as a separate electric motor.

[0091] According to embodiments herein, the control arrangement 21, 21 is configured to pass an electric current through the electric machine 5 while ensuring stand still of the vehicle 3. In this manner, heat is generated in the electric machine 5 which heats the powertrain 1 in a simple and energy-efficient manner, as is further explained herein.

[0092] The feature ensuring stand still of the vehicle 3 means that stand still of the vehicle 3 is ensured/accomplished relative to a surface 10 on which the vehicle 3 is positioned. Thus, according to embodiments of the present disclosure, electrical current is passed through the electric machine 5 while the vehicle 3 is standing still. Stand still of the vehicle 3 can be accomplished/ensured in different ways, as is further explained herein. The surface 10 may be a surface of a parking space, a road surface, or the like. However, as understood from the herein described, in some cases, the surface 10 may be a moving surface such as a surface of a ferry capable of transporting vehicles 3. Apparently, in such cases, stand still of the vehicle 3 is ensured/accomplished relative to such a moving surface according to the embodiments herein.

[0093] According to some embodiments, the control arrangement 21, 21 is configured to pass the electric current through the electric machine 5 in a manner ensuring stand still of the rotor 6 of the electric machine 5. The control arrangement 21, 21 may pass the electric current through the electric machine 5 in a non-torque producing manner. As an example, the control arrangement 21, 21 may pass the electric current in a continuous, i.e. non-alternating, manner trough wire windings of the electric machine 5. Thereby, the electric current through the electric machine 5 does not cause a torque applied to the rotor 6 and consequently no rotation of the rotor 6. As an alternative, the control arrangement 21, 21 may pass an alternating current through a number of wire windings of the electric machine 5 while ensuring stand still of the rotor 6. In such embodiments, the frequency of the alternating current, and/or the number of wire windings through which the electric current is passed, may be selected such that no torque is applied to the rotor 6 and consequently such that stand still of the rotor 6 is ensured.

[0094] The control arrangement 21, 21 may further ensure stand still of the rotor 6 by ensuring that the rotor 6 of the electric machine 5 is locked from rotating. The control arrangement 21, 21 may ensure that the rotor 6 of the electric machine 5 is locked from rotating by ensuring that a transmission brake is engaged and/or by ensuring that the transmission 7 is in an engaged state, i.e. that the rotor 6 of the electric machine 5 is rotationally locked to a wheel 9 of the vehicle 3, and that at least one of a wheel brake and a transmission brake is in an engaged state. Thus, according to these embodiments, the control arrangement 21, 21 may pass a torque producing current through the electric machine 5 while stand still of the rotor 6 of the electric machine 5 is ensured by locking rotation of the rotor 6.

[0095] According to some embodiments, the control arrangement 21, 21 is configured to pass the electric current through the electric machine 5 to rotate the rotor 6 of the electric machine 5 while ensuring stand still of the vehicle 3 relative the surface 10 onto which the vehicle 3 is positioned. According to these embodiments, the control arrangement 21, 21 may be configured to control the powertrain 1 to a state in which at least a portion 7 of the transmission 7 is disconnected from the one or more wheels 9, and then rotate the portion 7 of the transmission 7 using the rotor 6. In this manner, heat is generated in the electric machine 5 by the passing of electric current therethrough. Moreover, heat is generated in the portion 7 of the transmission 7 as a result of frictional resistance caused by the rotation of the portion 7 of the transmission 7.

[0096] In addition, heat may be distributed through the powertrain 1 in an improved manner by rotating the portion 7 of the transmission 7. The portion 7 of the transmission 7 is connected to the rotor 6 of the electric machine 5 and may be disconnected from the one or more wheels 9 by controlling the transmission 7 to a neutral state using the gear selector 41. Moreover, in embodiments in which the control arrangement 21, 21 passes the electric current through the electric machine 5 to rotate the rotor 6, gears and shafts of the full transmission 7 may be rotationally disconnected from the wheels 9 by controlling the coupling 43 to the disengaged state. According to these embodiments, the control arrangement 21, 21 may rotate gears and shafts of the full transmission 7 using the rotor 6 of the electric machine 5.

[0097] According to the illustrated embodiments, the lubricant pump 15 is operably connected to the portion 7 of the transmission 7 such that the lubricant pump 15 is operating upon rotation of the portion 7 of the transmission 7. Thus, when the portion 7 of the transmission 7 is rotated using the rotor 6, heat is distributed through the powertrain 1 by the circulation of lubricant through the lubricant circuit 13. In these embodiments, the control arrangement 21, 21 can be said to activate the lubricant pump 15 by rotating the portion 7 of the transmission 7 using the rotor 6. In further embodiments, such that those where the lubricant pump 15 is driven via another type of driving unit, the control arrangement 21, 21 may be configured to activate the lubricant pump 15 in another manner to distribute heat generated by the passing of the electric current through the electric machine 5.

[0098] According to some embodiments, the control arrangement 21, 21 may be configured to pass an electric current through the electric machine 5 in a manner ensuring stand still of the rotor 6 and pass an electric current through the electric machine 5 to rotate the rotor 6 in time-separated steps/intervals. As an example, the control arrangement 21, 21 may initiate a heating session by passing the electric current through the electric machine 5 in a manner ensuring stand still of the rotor 6 and then passing the electric current through the electric machine 5 to rotate the rotor 6.

[0099] According to some embodiments, the control arrangement 21, 21 is configured to switch back and forth between a first heating mode in which the electric current is passed through the electric machine 5 in a manner ensuring stand still of the rotor 6 and a second heating mode in which the electric current is passed through the electric machine 5 to rotate the rotor 6. Thereby, when operating in the first mode, the electric machine 5 is heated in a simple and energy efficient manner and when operating in the second mode, the electric machine 5 is heated in a simple and energy efficient manner while the generated heat is efficiently distributed through the powertrain 1. The powertrain 1 may comprise a number of temperature sensors including at least one temperature sensor configured to sense a current temperature of the electric machine 5. The number of temperature sensors may also include at least one temperature sensor configured to sense a current temperature of the transmission 7. The control arrangement 21, 21 may determine whether to operate in the first or in the second mode based on data obtained from the number of temperature sensors. The control arrangement 21, 21 may further switch between the first and second modes based on data from the number of temperature sensors.

[0100] According to some embodiments, the control arrangement 21, 21 is configured to input current temperature data representative of a current ambient temperature and/or a current temperature of a portion of the powertrain 1. The current temperature data may be inputted from a number of temperature sensors, such as one or more of the above mentioned type, and/or a temperature sensor configured to sense the current ambient temperature at the location of the vehicle 3. As an alternative, or in addition, the current temperature data may be inputted from another type of device, such as an external device, such as a sender sending data representative of the current ambient temperature at the location of the vehicle 3.

[0101] The control arrangement 21, 21 may be configured to control a duration of the passing of the electric current through the electric machine 5 based on the inputted current temperature data. Thereby, the control arrangement 21, 21 can heat the powertrain in an adaptive manner based on current temperature conditions. Thus, according to some embodiments, the control arrangement 21, 21 is configured to control a duration of the passing of the electric current through the electric machine 5 based on data representative of a current ambient temperature. According to such embodiments, the control arrangement 21, 21 may be configured to control a duration of the passing of the electric current such that the powertrain 1 is heated to a temperature within a wanted/determined temperature range. As an alternative, or in addition, according to some embodiments, the control arrangement 21, 21 is configured to control a duration of the passing of the electric current through the electric machine 5 based on data representative of current temperature of a portion of the powertrain 1. According to these embodiments, as well as other embodiments described herein, the control arrangement 21, 21 may be configured to control a duration of the passing of the electric current such that the powertrain 1 is heated to a temperature within a wanted/determined temperature range. In all these embodiments, the control arrangement 21, 21 may control the passing of the electric current such that the temperature of the powertrain 1 is maintained within the wanted/determined temperature range once the temperature of the powertrain 1 has reached the wanted/determined temperature range.

[0102] The control arrangement 21, 21 may be configured to control a duration of the passing of the electric current through the electric machine 5 based on the inputted current temperature data when operating in the first mode as well as when operating in the second mode. That is, the control arrangement 21, 21 may be configured to control the duration of the passing of the electric current through the electric machine 5 in the manner ensuring stand still of the rotor 6 of the electric machine 5 based on the inputted current temperature data. As an alternative, or in addition, the control arrangement 21, 21 may be configured to control the duration of the passing of the electric current through the electric machine 5 in the manner rotating the rotor 6 of the electric machine 5 based on the inputted current temperature data. According to embodiments herein, the duration of the passing of the electric current through the electric machine 5 may range from a number of seconds to a number of minutes.

[0103] According to some embodiments, the control arrangement 21, 21 is configured to estimate a time at which the vehicle 3 is expected to be operated and initiate the passing of the electric current through the electric machine 5 a predetermined time before the estimated time. Thereby, the control arrangement 21, 21 can initiate heating of the powertrain 1 a predetermined time before the vehicle 3 is expected to be operated so as to obtain a wanted/determined temperature of the powertrain 1 when operation of the vehicle is expected to be initiated. The control arrangement 21, 21 may input and/or store data which can be used to estimate the time at which the vehicle 3 is expected to be operated. Such data may for example comprise calendar data, historic data of times the vehicle 3 has been operated, and/or driving request data, for example sent from an external device.

[0104] According to some embodiments, the control arrangement 21, 21 is configured to input current temperature data representative of a current ambient temperature and/or a current temperature of a portion of the powertrain 1, and set a length of the predetermined time based on the current temperature data. In this manner, a wanted/determined temperature level of the powertrain 1 can be reached with higher certainty before operation of the vehicle 3 is initiated.

[0105] As is further explained herein, according to the illustrated embodiments, the control arrangement 21, 21 is configured to heat the propulsion battery 17 using heat generated by the passing of the electric current through the electric machine 5. That is, according to the illustrated embodiments, the powertrain 1 comprises a battery coolant circuit 19. The battery coolant circuit 19 comprises a coolant pump 23 configured to pump coolant through the battery coolant circuit 19 to regulate the temperature of the propulsion battery 17. The battery coolant circuit 19 may comprise a liquid coolant such, as an aqueous coolant mixture. The battery coolant circuit 19 extends through the propulsion battery 17 such that coolant flowing through the battery coolant circuit 19 is in heat exchanging contact with the propulsion battery 17.

[0106] Moreover, according to the illustrated embodiments, the battery coolant circuit 19 extends through the power module 21 and through the electric machine 5 such that coolant flowing through the battery coolant circuit 19 is in heat exchanging contact with the power module 21 and with the electric machine 5. Thus, according to the illustrated embodiments, the battery coolant circuit 19 is further configured to regulate the temperature of the power module 21 and the electric machine 5. According to some embodiments, the electric machine 5 may comprise an oil circuit configured to cool the electric machine 5, and wherein the powertrain 1 may comprise a heat exchanger configured to exchange heat between oil of the oil circuit and a liquid coolant, such as an aqueous coolant mixture of the battery coolant circuit 19. Such a heat exchanger and oil circuit are not shown in FIG. 2.

[0107] The battery coolant circuit 19 further comprises a heat exchanger 45 arranged to cool coolant flowing through the heat exchanger 45. The heat exchanger 45 may be a radiator and may be arranged at a front portion of the vehicle 3 to be subjected to a flow of air during movement of the vehicle 3. The battery coolant circuit 19 further comprises a bypass line 47 bypassing the heat exchanger 47 and a valve 49 controllable between a first state, in which the valve 49 directs coolant through the heat exchanger 45 and a second state, in which the valve 49 directs coolant through the bypass line 47.

[0108] The control arrangement 21, 21 may be configured to heat the propulsion battery 17 using heat generated by the passing of the electric current through the electric machine 5 by activating the coolant pump 23 of the battery coolant circuit 19. In this manner, heat generated in the powertrain 1, by the passing of the electric current through the electric machine 5, is distributed to the propulsion battery 17 via the battery coolant circuit 19. Since the propulsion battery 17 is heated, the control arrangement 21, 21 provides conditions for an improved efficiency of the propulsion battery 17 thereby providing conditions for an improved available operational range of the vehicle 3. Moreover, a more even temperature of the components of the powertrain 1 can be obtained by activating the coolant pump 23 of the battery coolant circuit 19. In connection to an activation of the coolant pump 23, the control arrangement 21, 21 may be configured to control the valve 49 to the second state. Thereby, the coolant will flow through the bypass line 47 and waste of heat energy via the heat exchanger 45 is avoided in a heating session of the powertrain 1. According to some embodiments, the powertrain 1 comprises a separate heating circuit configured to heat the propulsion battery 17 using heat generated by the electric machine 5. According to such embodiments, the control arrangement 21, 21 may be configured to heat the propulsion battery 17 using heat generated by the passing of the electric current through the electric machine 5 by activating a coolant pump of such a separate heating circuit.

[0109] According to the illustrated embodiments, the powertrain 1 comprises a heat exchanger 26 configured to heat an occupant compartment 25 of the vehicle 3 using heat from the powertrain 1. The occupant compartment 25 is schematically indicated in FIG. 1 and FIG. 2. In more detail, according to the illustrated embodiments, the powertrain 1 comprises an occupant compartment heating circuit 27, wherein the heat exchanger 26 is arranged in the occupant compartment heating circuit 27. The control arrangement 21, 21 may heat the occupant compartment 25 using heat generated by the passing of the electric current through the electric machine 5 by circulating coolant through the heat exchanger 26. According to the illustrated embodiments, the occupant compartment heating circuit 27 is arranged as a coolant branch of the battery coolant circuit 19. Moreover, according to the illustrated embodiments, the occupant compartment heating circuit 27 comprises a coolant pump 29. According to these embodiments, the control arrangement 21, 21 may heat the occupant compartment 25 using heat generated by the passing of the electric current through the electric machine 5 by activating the coolant pump 29 of the occupant compartment heating circuit 27.

[0110] According to further embodiments, the occupant compartment heating circuit 27 may be a separate circuit in heat exchanging contact with portions of the powertrain 1. Also in such embodiments, the control arrangement 21, 21 may heat the occupant compartment 25 using heat generated by the passing of the electric current through the electric machine 5 by activating a coolant pump of such an occupant compartment heating circuit. According to still further embodiments, the occupant compartment heating circuit 27 is arranged as a coolant branch of the battery coolant circuit 19 but comprise no coolant pump 29. Instead, the coolant branch, and/or the battery coolant circuit 19, may comprise a valve controllable to regulate the flow through a heat exchanger 26 which is configured to heat the occupant compartment 25. According to such embodiments, the control arrangement 21, 21 may heat the occupant compartment 25 using heat generated by the passing of the electric current through the electric machine 5 by activating the coolant pump 23 of the battery coolant circuit 19 and control such a valve to direct coolant through the heat exchanger 26.

[0111] According to the illustrated embodiments, the heat exchanger 26 is a radiator, wherein a fan 51 is configured to generate an airflow through the heat exchanger 26 into the occupant compartment 25 to heat the occupant compartment 25. The control arrangement 21, 21 may be operably connected to the fan 51 and may activate the fan 51 to obtain an increased heat transfer from the powertrain 1 to the occupant compartment 25. Moreover, the control arrangement 21, 21 may be operably connected to an air valve arrangement, also referred to as an air door arrangement, controllable between different states to direct air downstream of the heat exchanger 26 to the occupant compartment 25 and/or to the surroundings. According to such embodiments, the control arrangement 21, 21 may control the air valve arrangement to a state in which the air downstream of the heat exchanger 26 is directed to the occupant compartment 25 in a heating session of the powertrain 1. According to further embodiments, the heat exchanger 26 may be a radiator arranged inside of the occupant compartment 25.

[0112] According to some embodiments, the control arrangement 21, 21 is configured to perform the herein described procedure of passing the electric current through the electric machine 5 to heat the powertrain 1 only when the charging module 31 is connected to the external power source 33. The control arrangement 21, 21 may be configured to detect when the charging module 31 is connected to the external power source 33 and may be configured to pass the electric current through the electric machine 5 to heat the powertrain 1 only when it is detected that the charging module 31 is connected to the external power source 33. Thereby, electrical energy from the external power source 33 is used to heat the powertrain 1 instead of electrical energy stored in the propulsion battery 17. In this manner, an increased available operational range of the vehicle 3 can be ensured when operation of the vehicle 3 is initiated.

[0113] According to embodiments herein, the control arrangement 21, 21 may be configured to ensure stand still of the vehicle 3 relative to a surface 10 on which the vehicle 3 is positioned by ensuring that a wheel brake of the vehicle 3 is engaged, and/or that another type of brake or arrangement of the vehicle 3, which locks one or more wheels of the vehicle 3 from rotating, is engaged, such as a parking brake, a transmission brake, or the like.

[0114] FIG. 3 illustrates a method 100 of heating a powertrain of a vehicle. The powertrain may be a powertrain 1 according to embodiments explained with reference to FIG. 2 and the vehicle may be a vehicle 3 explained with reference to FIG. 1. Therefore, below, simultaneous reference is made to FIG. 1-FIG. 3. The method 100 is a method 100 of heating a powertrain 1 of a vehicle 3, wherein the powertrain 1 comprises an electric machine 5 configured to provide motive power to the vehicle 3. The method 100 comprises the step of: [0115] passing 110, 120 an electric current through the electric machine 5 while ensuring stand still of the vehicle 3 relative to a surface 10 on which the vehicle 3 is positioned.

[0116] According to some embodiments, the step of passing 110 the electric current through the electric machine 5 comprises the step of: [0117] passing 110 the electric current through the electric machine 5 in a manner ensuring stand still of a rotor 6 of the electric machine 5.

[0118] According to some embodiments, the step of passing 120 the electric current through the electric machine 5 comprises the step of: [0119] passing 120 the electric current through the electric machine 5 to rotate a rotor 6 of the electric machine 5.

[0120] According to some embodiments, the powertrain 1 comprises a transmission 7 configured to transmit power between the electric machine 5 and one or more wheels 9 of the vehicle 3, and wherein the method 100 comprises the step of: [0121] controlling 119 the powertrain 1 to a state in which at least a portion 7 of the transmission 7 is disconnected from the one or more wheels 9, and [0122] rotating 121 the portion 7 of the transmission 7 using the rotor 6.

[0123] According to some embodiments, the step of passing 110, 120 an electric current through the electric machine 5 comprises the time-separated steps of: [0124] passing 110 an electric current through the electric machine 5 in a manner ensuring stand still of the rotor 6, and [0125] passing 120 an electric current through the electric machine 5 to rotate the rotor 6.

[0126] According to some embodiments, the step of passing 110 the electric current through the electric machine 5 in a manner ensuring stand still of the rotor 6 is performed prior to the step of passing 120 the electric current through the electric machine 5 to rotate the rotor 6.

[0127] According to some embodiments, the method 100 comprises the step of: [0128] switching 125 back and forth between a first heating mode in which the electric current is passed through the electric machine 5 in a manner ensuring stand still of the rotor 6 and a second heating mode in which the electric current is passed through the electric machine 5 to rotate the rotor 6.

[0129] According to some embodiments, the method 100 comprises the steps of: [0130] inputting 105 current temperature data representative of a current ambient temperature and/or a current temperature of a portion of the powertrain 1, and [0131] controlling 130 a duration of the passing of the electric current through the electric machine 5 based on the inputted current temperature data.

[0132] According to some embodiments, the method 100 comprises the steps of: [0133] estimating 101 a time at which the vehicle 3 is expected to be operated, and [0134] initiating 108 the step of passing 110, 120 the electric current through the electric machine 5 a predetermined time before the estimated time.

[0135] According to some embodiments, the method 100 comprises the steps of: [0136] inputting 103 current temperature data representative of a current ambient temperature and/or a current temperature of a portion of the powertrain 1, and [0137] setting 104 a length of the predetermined time based on the current temperature data.

[0138] According to some embodiments, the powertrain 1 comprises a lubricant circuit 13 comprising a lubricant pump 15 configured to pump lubricant through the lubricant circuit 13 to lubricate portions of the powertrain 1, and wherein the method 100 comprises the step of: [0139] activating 135 the lubricant pump 15.

[0140] According to some embodiments, the powertrain 1 comprises a propulsion battery 17, and wherein the method 100 comprises the step of: [0141] heating 137 the propulsion battery 17 using heat generated by the passing of the electric current through the electric machine 5.

[0142] According to some embodiments, the powertrain 1 comprises a battery coolant circuit 19 comprising a coolant pump 23 configured to pump coolant through the battery coolant circuit 19 to regulate the temperature of the propulsion battery 17, and wherein the step of heating 137 the propulsion battery 17 comprises the step of: [0143] activating 139 the coolant pump 23 of the battery coolant circuit 19.

[0144] According to some embodiments, the vehicle 3 comprises an occupant compartment 25, and wherein the method 100 comprises the step of: [0145] heating 140 the occupant compartment 25 using heat generated by the passing of the electric current through the electric machine 5.

[0146] According to some embodiments, the powertrain 1 comprises a heat exchanger 26 configured to heat the occupant compartment 25 using heat from the powertrain 1, and wherein the step of heating 140 the occupant compartment 25 comprises the step of: [0147] circulating 142 coolant through the heat exchanger 26.

[0148] According to some embodiments, the vehicle 3 comprises a propulsion battery 17 and a charging module 31 connectable to an external power source 33 to charge the propulsion battery 17 using electricity from the external power source 33, and wherein the step/steps of passing 110, 120 the electric current through the electric machine 5 is/are performed when the charging module 31 is connected to the external power source 33. According to some embodiments, the step/steps of passing 110, 120 the electric current through the electric machine 5 is/are performed only when the charging module 31 is connected to the external power source 33.

[0149] According to some embodiments, the method 100 comprises the step of: [0150] locking rotation of one or more wheels 9 of the vehicle 3 to ensure stand still of the vehicle 3 relative to a surface 10 on which the vehicle 3 is positioned.

[0151] According to some embodiments, the step of locking rotation of one or more wheels 9 of the vehicle 3 comprises at least one of the steps: [0152] controlling a wheel brake of the vehicle 3 to an engaged state, and [0153] controlling another type of brake or arrangement of the vehicle 3 to an engaged state to lock one or more wheels 9 from rotating.

[0154] It will be appreciated that the various embodiments described for the method 100 are all combinable with the control arrangement 21, 21 as described herein. That is, the control arrangement 21, 21 may be configured to perform any one of the method steps 101, 103, 104, 105, 108, 110, 119, 120, 121, 125, 130, 135, 137, 139, 140, and 142 of the method 100.

[0155] FIG. 4 illustrates computer-readable medium 200 comprising instructions which, when executed by a computer, cause the computer to carry out the method 100 according to some embodiments.

[0156] According to some embodiments, the computer-readable medium 200 comprises a computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method 100 according to some embodiments.

[0157] The control arrangement 21, 21 may be connected to one or more components of the powertrain 1, and/or one or more components of the vehicle 3, in order to perform the method 100 illustrated in FIG. 3. According to some embodiments, control arrangement 21, 21 comprises a control unit 21 and a power module 21. The control unit 21 may be operably connected to power module 21. The control unit 21 may control/cause the power module 21 to pass the electric current through the electric machine 5 while ensuring stand still of the vehicle 3 so as to heat the powertrain 1.

[0158] One skilled in the art will appreciate that the method 100 of heating a powertrain 1 of a vehicle 3 may be implemented by programmed instructions. These programmed instructions are typically constituted by a computer program, which, when it is executed in the control arrangement 21, 21, ensures that the control arrangement 21, 21 carries out the desired control, such as the method steps 101, 103, 104, 105, 108, 110, 119, 120, 121, 125, 130, 135, 137, 139, 140, and 142 described herein. The computer program is usually part of a computer program product 200 which comprises a suitable digital storage medium on which the computer program is stored.

[0159] The control arrangement 21, 21 may comprise a calculation unit which may take the form of substantially any suitable type of processor circuit or microcomputer, e.g. a circuit for digital signal processing (digital signal processor, DSP), a Central Processing Unit (CPU), a processing unit, a processing circuit, a processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The herein utilised expression calculation unit may represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some or all of the ones mentioned above.

[0160] The control arrangement 21, 21 may further comprise a memory unit, wherein the calculation unit may be connected to the memory unit, which may provide the calculation unit with, for example, stored program code and/or stored data which the calculation unit may need to enable it to do calculations. The calculation unit may also be adapted to store partial or final results of calculations in the memory unit. The memory unit may comprise a physical device utilised to store data or programs, i.e., sequences of instructions, on a temporary or permanent basis. According to some embodiments, the memory unit may comprise integrated circuits comprising silicon-based transistors. The memory unit may comprise e.g. a memory card, a flash memory, a USB memory, a hard disc, or another similar volatile or non-volatile storage unit for storing data such as e.g. ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), etc. in different embodiments.

[0161] The control arrangement 21, 21 is connected to components of the powertrain 1 and/or the vehicle 3 for receiving and/or sending input and output signals. These input and output signals may comprise waveforms, pulses or other attributes which the input signal receiving devices can detect as information and which can be converted to signals processable by the control arrangement 21, 21. These signals may then be supplied to the calculation unit. One or more output signal sending devices may be arranged to convert calculation results from the calculation unit to output signals for conveying to other parts of the vehicle's control system and/or the component or components for which the signals are intended. Each of the connections to the respective components of the powertrain 1 and/or the vehicle 3 for receiving and sending input and output signals may take the form of one or more from among a cable, a data bus, e.g. a CAN (controller area network) bus, a MOST (media orientated systems transport) bus or some other bus configuration, or a wireless connection.

[0162] In the embodiments illustrated, the powertrain 1 comprises a control arrangement 21, 21 but might alternatively be implemented wholly or partly in two or more control arrangements or two or more control units.

[0163] Control systems in modern vehicles generally comprise a communication bus system consisting of one or more communication buses for connecting a number of electronic control units (ECUs), or controllers, to various components on board the vehicle. Such a control system may comprise a large number of control units and taking care of a specific function may be shared between two or more of them. Vehicles of the type here concerned are therefore often provided with significantly more control arrangements than depicted in FIG. 2, as one skilled in the art will surely appreciate.

[0164] The computer program product 200 may be provided for instance in the form of a data carrier carrying computer program code for performing at least some of the method steps 101, 103, 104, 105, 108, 110, 119, 120, 121, 125, 130, 135, 137, 139, 140, and 142 according to some embodiments when being loaded into one or more calculation units of the control arrangement 21, 21. The data carrier may be, e.g. a CD ROM disc, as is illustrated in FIG. 4, or a ROM (read-only memory), a PROM (programmable read-only memory), an EPROM (erasable PROM), a flash memory, an EEPROM (electrically erasable PROM), a hard disc, a memory stick, an optical storage device, a magnetic storage device or any other appropriate medium such as a disk or tape that may hold machine readable data in a non-transitory manner. The computer program product may furthermore be provided as computer program code on a server and may be downloaded to the control arrangement 21, 21 remotely, e.g., over an Internet or an intranet connection, or via other wired or wireless communication systems.

[0165] As understood from the herein described, the electrical current is passed through the electric machine 5 while the vehicle 3 is standing still relative to a surface 10 on which the vehicle 3 is positioned. Accordingly, the step/steps of passing 110, 120 an electric current through the electric machine 5 is/are performed while the vehicle 3 is standing still relative to a surface 10 on which the vehicle 3 is positioned. Therefore, throughout this disclosure, the wording while ensuring stand still of the vehicle 3 may be replaced with the wording while the vehicle 3 is standing still or with the wording while the vehicle 3 is standing still relative to a surface 10 on which the vehicle 3 is positioned.

[0166] It is to be understood that the foregoing is illustrative of various example embodiments and that the invention is defined only by the appended independent claims. A person skilled in the art will realize that the example embodiments may be modified, and that different features of the example embodiments may be combined to create embodiments other than those described herein, without departing from the scope of the present invention, as defined by the appended independent claims.

[0167] As used herein, the term comprising or comprises is open-ended, and includes one or more stated features, elements, steps, components, or functions but does not preclude the presence or addition of one or more other features, elements, steps, components, functions, or groups thereof.