WO2008136738A1

WO2008136738A1 - Controlled shut down

Info

Publication number: WO2008136738A1
Application number: PCT/SE2008/050452
Authority: WO
Inventors: Johan Lundmark
Original assignee: Scania Cv Ab (Publ)
Priority date: 2007-05-04
Filing date: 2008-04-22
Publication date: 2008-11-13
Also published as: SE531137C2; SE0701085L; DE112008001221T5; DE112008001221B4

Abstract

The invention concerns power control in a motor vehicle. A main power source (110) is configured to supply electric power to a set of components (C1, C2,, Cm) in the vehicle. A main power switch (120) is configured to selectively enable or disable the supply of electric power from the main power source (110) to the set of components (C1, C2,, Cm), and an ignition switch (125) is configured to selectively enable or disable the supply of electric power from the main power source (110) to a subset (C1, C2,, Ck) of the set of components (C1, C2,, Cm). Moreover, the ignition switch (125) is arranged in series with the main power switch (120), such that the subset (C1, C2,, Ck) is excluively powered if both the main power switch (120) and the ignition switch (125) are positioned in an active state. A control unit (130) is configured to receive: a respective indication (131, 132) of whether or not each of the main power switch (120) and the ignition switch (125) are positioned in an active state or an inactive state, and a number of status signals (s 1, s 2,, s n) reflecting conditions for a given set of functions in the vehicle. Based thereon the control unit (130) is adapted to control the supply of power from the main power source (110) to the set of components (C1, C2,, Cm), such that one scenario from a group of power-down scenarios is selected based on the status signals (s 1, s 2,, s n) and a set of control signals (Ctrl1) is produced which is adapted to cause a powering down of the vehicle being consistent with the selected scenario. Hence, a controlled shut-down can be accomplished when appropriate. Furthermore, emergency power-down is enabled whenever necessary.

Description

Controlled Shut Down

THE BACKGROUND OF THE INVENTION AND PRIOR ART

The present invention relates generally to solutions for shutting down vehicular systems. More particularly the invention relates to a power control system according to the preamble of claim 1 and a motor vehicle according to claim 8. The invention also relates to a method for controlling the power supply in a motor vehicle according to the preamble of claim 9 and a computer program product according to claim 15.

Modern automotive vehicles are highly complex machines which include many interconnected computerized units. As a result, powering up and powering down the vehicle can be a rather intricate and time consuming procedure. For example, to ensure a controlled shut down, the power supply to some units may have to be continued during a period after that the ignition has been turned off. Analogously, powering up the computerized units may require a booting procedure which delays departure. Therefore, start-up and shut down demands particular considerations.

EP 952 036 A2 describes one example of a solution for accomp- lishing a controlled shut down of critical vehicular components. The starting/stopping control system here has a main switch which is left turned on if it is detected that the driver leaves the vehicle when the engine is automatically stopped. Namely, under this condition it can be expected that the driver will con- tinue to operate the vehicle relatively soon, and therefore having the main switch turned on saves time at the future restart. A buzzer is sounded to remind the driver that the main switch is turned on.

US 2005/0055498 discloses a solution for operating automotive computing devices, wherein circuitry is provided to ensure that static random access memories receive back up power at the appropriate time. Hence, in the event of power loss the software can continue to operate when the power is later restored. Moreover, there exist situations when the vehicle and its units must be powered down immediately. For example, in case of a crash and/or a fire involving a transport vehicle for explosive goods. Consequently, depending on the circumstances, the ve- hide can/should be powered down more or less quickly. However, there is yet no satisfactory solution for automatically determining a most appropriate power-down procedure for each given situation.

SUMMARY OF THE INVENTION The object of the present invention is therefore to provide a solution, which alleviates the problems above and thus offers an adaptive power down for a vehicle.

According to one aspect of the invention, the object is achieved by the initially described system, wherein the control unit is ad- apted to receive a number of status signals reflecting conditions for a given set of functions in the vehicle. Based on the current states of the main power and the ignition switches, the control unit is adapted to select one scenario from a group of power- down scenarios based on the status signals. Then, the control unit is adapted to produce a set of control signals being adapted to cause a powering down of the vehicle which is consistent with the selected scenario.

This system is advantageous because thereby controlled shutdown and stand-by operation can be accomplished when appro- priate. At the same time, emergency power-down can be effected if necessary.

According to one embodiment of this aspect of the invention, the group of power-down scenarios includes a stand-by scenario, a fast power-down scenario and an emergency power-down sce- nario. In the stand-by scenario, electric power is continued to be supplied to at least one component in the set of components during a delay interval. In the fast power-down scenario, the supply of electric power to the set of components is discontinued as soon as possible while minimizing the risk that the com- ponents take damage there from. In the emergency power-down scenario, however, the supply of electric power to the set of components is discontinued immediately (i.e. without considering whether or not this is harmful to the affected units/compo- nents). Hence, the most important shut-down situations are tackled efficiently.

According to another embodiment of this aspect of the invention, the control unit is adapted to select the stand-by scenario if: the main power switch is positioned in the active state, the ignition switch is positioned in the inactive state, and a first status signal is received which reflects that at least one door of the vehicle is locked (e.g. the doors to the driver's cabin). Namely, in such a situation it can be expected that the driver has left the vehicle, however that he/she will return relatively soon. Therefore, during the delay interval, it is advantageous to maintain the power supply to those components that require a relatively long start-up time.

According to yet another embodiment of this aspect of the invention, the control unit is adapted to select the fast power- down scenario if the at least one door remains locked at expiry of the delay interval. Thereby, unnecessary powering of the vehicle's components is avoided, and the battery power is economized.

According to still another embodiment of this aspect of the in- vention, the control unit is adapted to select the fast power- down scenario if the control unit receives the consecutive indications that: the ignition switch is positioned in the inactive state, the main switch is repositioned from the active to the inactive state, and at least one door of the vehicle is locked (e.g. the doors to the driver's cabin). Namely, in such a situation it is reasonable to expect that the driver will be away from the vehicle a substantial time. To save battery power, it is therefore advantageous to power down the vehicle as fast as possible.

According to a further embodiment of this aspect of the inven- tion, the control unit is adapted to select the emergency power- down scenario if the control unit receives indications that: an operator is located in a driver's seat of the vehicle, the ignition switch is positioned in the active state, and the main switch is repositioned from the active to the inactive state. Such a situa- tion is clearly a sign of emergency, and therefore it can be expected that an immediate shut down is desirable.

According to another embodiment of this aspect of the invention, the control unit is adapted to receive the indication that the operator is located in the drivers seat by means of one or more of the following: a status signal from a seat-activated switch, a status signal from an image recorder configured to repeatedly register image data representing an area in proximity of the seat, or a Doppler-based status signal representing a reflected probing signal transmitted towards an area of the seat. Thus, a reliable determination can be made as to whether or not an operator occupies the driver's seat. Naturally, alternative or complementary sensors may also be used to determine if a driver is present or not.

According to another aspect of the invention, the object is achie- ved by the motor vehicle described initially, wherein the vehicle includes the proposed system for controlling the delivery of electric power to the vehicle's components.

According to another aspect of the invention, the object is achieved by the method described initially, wherein one scenario is selected from a group of power-down scenarios based on indications of whether the main power and ignition switches are positioned in a respective active or inactive state and a number of status signals reflecting conditions for a given set of functions in the vehicle. Then, a set of control signals are produced which are adapted to cause a powering down of the vehicle which is consistent with the selected scenario. The advantages of this method, as well as the preferred embodiments thereof, are apparent from the discussion hereinabove with reference to the proposed vehicle arrangement.

According to a further aspect of the invention the object is achieved by a computer program product loadable into a memory of a computer. The program product includes software adapted to control the above proposed method when the program product is run on a computer.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is now to be explained more closely by means of embodiments, which are disclosed as examples, and with reference to the attached drawings.

Figure 1 shows a block diagram over a power control sys- tern according to one embodiment of the invention,

Figures 2a-c show diagrams illustrating examples of power- down scenarios according to embodiments of the invention, Figure 3 shows a motor vehicle equipped with the proposed power control system, and

Figure 4 shows a flow diagram illustrating the general method according to the invention.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION We refer initially to Figure 1 , which shows a block diagram over a power control system for a motor vehicle according to one embodiment of the invention. The system includes a main power source 1 10, a main power switch 120, an ignition switch 125 and a control unit 130.

The main power source 1 10 is configured to supply electric power to a set of components C1 , C2, ... , Cm in the vehicle, preferably all the components in the vehicle. However, some of these components may receive electric power via an auxiliary power source, which in turn, is powered/charged by the main power source 1 10. Here, we presume that the main power source 1 10 has a nominal voltage U_bat-

The main power switch 120 is configured to selectively enable or disable the supply of electric power from the main power source 1 10 to the set of components C1 , C2, ... , Cm. This power supply is preferably accomplished by means of at least one control signal CtrM generated by the control unit 130 in response to an indication at a first input 131 of the control unit 130. Hence, in this example, reception of the voltage U_bat at a first input 131 indicates that the main power switch 120 is in an active state, whereas a zero/gnd-voltage indicates that the main power switch 120 is in an inactive state.

The ignition switch 125, which may be controlled by a key, a push button or a smart card, is configured to selectively enable or disable the supply of electric power from the main power source 1 10 to a subset C1 , C2, ... , Ck of the set of components C1 , C2, ... , Cm, such as the engine and other vital parts of the vehicle. The ignition switch 125 may include a number of individual sub-switches 125a and 125b each arranged to cause power to be fed to specific components/units in the vehicle depending on how much an ignition key is turned. For instance, activation of a first sub-switch 125a may result in that a first group of com- ponents is powered (e.g. including the sound system), whereas activation of a second sub-switch 125b may result in that a second group of components is powered (e.g. including the engine). Naturally, any number of sub-switches other than the illustrated two switches is equally well conceivable according to the invention. Furthermore, the ignition switch 125 is arranged in series with the main power switch 120, such that the subset of components C1 , C2, ... , Ck is powered only if both the main power switch 120 and the ignition switch 125 are positioned in an active state. Of course, Figure 1 illustrates this in a highly schematic manner. An actual implementation typically includes numerous relays and switches to accomplish this functionality.

Analogous to the above, the control unit 130 preferably has at least one second input 132a and 132b respectively adapted to receive a respective indication as to whether the ignition switch 125 is positioned in an active state (voltage = U_bat) or an inactive state (voltage = gnd). The control unit 130 is adapted to generate at least one control signal CtrM in response the indi- cation received via the second input(s) 132a/132b. The control unit 130 is configured to also receive a number of status signals s-i , S₂, ... , S_n reflecting conditions for a given set of functions in the vehicle. Based on these signals s-i , S₂, ... , S_n, and the cur- rent states of the main power switch 120 and the ignition switch, the control unit 130 is adapted to select one scenario from a group of power-down scenarios. Then, the control unit 130 is adapted to produce a set of control signals CtrM being adapted to cause a powering down of the vehicle which is consistent with the selected scenario.

According to the invention, it is presumed that the vehicle contains at least one back-up power source, such that whenever the energy supply from the main power source 1 10 is interrupted as the result of a powering down command caused by deactivation of the ignition switch 125 and/or the main switch 1 10, the affected components/units can receive adequate power during any subsequent powering down procedure. For example, one or more components/units may be provided with a dedicated local power back up as is illustrated by means of a secondary battery 1 15 connected to the control unit 130. Alternatively, or as a complement thereto, one or more components/units may receive back up power from the main power source 1 10 via a relay 1 17 controlled by the control unit 130 by means of at least one control signal Ctrl2. Hence, the nominal voltage U_bat can conti- nued to be fed the components/units during any required powering down procedure.

According to one embodiment of the invention, the group of power-down scenarios includes a stand-by scenario, a fast power- down scenario and an emergency power-down scenario. The stand-by scenario involves continuing to supply electric power to at least one component in the set of components C1 , C2, ... , Cm during a delay interval. Thus, within this interval the vehicle can be restarted relatively quickly (inter alia because booting-up and other time-consuming procedures are avoided). The fast power- down scenario involves discontinuing the supply of electric power to the set of components C1 , C2, ... , Cm as soon as possible. Nevertheless, the shut-down is here effected in such a man- ner that the risk is minimized that the components are damaged. For example, voltage transients are reduced and the units/components are allocated time to store relevant parameters etc. The emergency power-down scenario involves an immediate discon- tinuing of the electric power supply to the all the components in the set C1 , C2, ... , Cm. I.e. in this case, the procedure does not aim at avoiding any effects that may harm the components. Instead, safety is the main concern. Thus, this scenario can be applied if the vehicle transports explosive goods and it is sus- pected the vehicle is involved in a crash and/or a fire.

According to one embodiment of the invention, the control unit 130 is adapted to select the stand-by scenario if:

(a) the main power switch 120 is positioned in the active state,

(b) the ignition switch 125 is positioned in the inactive state, and (c) at least one first status signal s<_\ received by the control unit 130 reflects that at least one door of the vehicle is locked.

The condition (b) indicates that the driver has turned off the engine. However since he/she has left the main power switch 120 active (condition (b)), it is reasonable to expect that the engine will be restarted relatively soon. The locking of the door(s), e.g. to the driver's cabin, (condition (c)) indicates that the driver may temporarily leave the vehicle outside his/her field of view, for example to take a short brake. Therefore, a partial down-powering of the vehicle may be appropriate, however a subset of its components remain powered during the delay interval T_D.

Figure 2a shows a diagram which illustrates the stand-by scenario. The diagram represents the output voltage U on the vertical axis and the time t along the horizontal axis. We assume that the conditions (a), (b) and (c) are fulfilled at a first point in time t-| . This initiates the delay interval T_D. Preferably, if at expiry of the delay interval T_D (at t = t_D) the at least one door remains locked, the control unit 130 is adapted to select the fast power- down scenario (see below). Nevertheless, if at least one of the at least one door is unlocked within the delay interval T_D, the control unit 130 is preferably adapted to restart the delay interval T_D once. Thereafter, the fast power-down scenario follows provided that the control unit 130 has not received an indication via the second input 132 that the vehicle is to be restarted.

Figure 2b shows a diagram which illustrates an example of the fast power-down scenario according to one embodiment of the invention. Here, we assume that the control unit 130 receives the consecutive indications that:

(i) the ignition switch 125 is positioned in the inactive state, (ii) the main switch (120) is repositioned from the active to the inactive state, and

(iii) at least one door of the vehicle is locked.

In this example, the condition (i) is fulfilled at a first point in time t-i ; the condition (ii) is fulfilled at a second point in time t₂; and the condition (iii) is fulfilled at a third point in time t₃. Consequently, the control unit 130 is adapted to generate the control signals Ctrl 1 /Ctrl2 such that the supply of electric power to the set of components C1 , C2, ... , Cm is discontinued as soon as possible after the third point in time t₃ while minimizing the risk that the components take any damage as a result thereof.

According to one embodiment of the invention, the control unit 130 is adapted to select the emergency power-down scenario if the control unit 130 receives indications that:

(1 ) an operator is located in a driver's seat of the vehicle, (2) the ignition switch 125 is positioned in the active state, and

(3) the main switch 120 is repositioned from the active to the inactive state.

Figure 2c shows a diagram which illustrates an example of such an emergency power-down scenario. At a point in time t₄, we as- sume that the conditions (1 ), (2) and (3) are all fulfilled. Therefore, the control unit 130 is adapted to generate the control signals Ctrl 1 /Ctrl2 such that the supply of electric power to the set of components C1 , C2, ... , Cm is discontinued immediately. Preferably, the control unit 130 is adapted to receive the indication in respect of the condition (1 ) (whether or not an operator is located in the drivers seat) by means of one or more of the following: a status signal S₂ from a seat-activated switch, a status signal S₂ from an image recorder (e.g. a video recorder) configured to repeatedly register image data representing an area in proximity of the seat, or a Doppler-based status signal S₂ representing a reflected probing signal transmitted towards an area of the seat (e.g. a radar, sonar or infrared signal).

The above-mentioned scenarios should be regarded as important examples of different power-down strategies, which the proposed control unit 130 is capable of implementing automatically. Naturally, numerous additional/alternative power-down scenarios are also conceivable. For example, a status signal received by the control unit 130 may reflect whether or not the vehicle's parking lights are activated. Namely, such a signal can be used to estimate the probability that the driver returns to the vehicle within a particular interval. Moreover, if the cabin alarm is activated while at least one door to the cargo compartment is open, this is preferably interpreted as a loading/unloading situation. Hence, in such a situation, it is reasonable to expect that the driver returns to the vehicle relatively soon, and it therefore makes sense to maintain the power supply to a subset of the components C1 , C2, ... , Cm during a delay interval T_D. Moreover, depending on the status signals, the duration of the delay interval T_D may be adapted to attain a desirable balance between power consumption and start-up time. Namely, certain combinations of statuses may indicate a relatively short driver absence from the vehicle, whereas other combinations of statuses may indicate a longer absence.

The automotive industry has developed towards an increased use of network solutions for controlling various kinds of units and processes in the vehicles. For instance, the Controller Area Network (CAN), the Time Triggered CAN (TTCAN), the FlexRay, the Media Oriented System Transport (MOST) and the Byte- Flight standards specify means of accomplishing these types of networks in trucks, busses and other motor vehicles. By means of a CAN, or a similar network, a very large number of vehicle functions may be accomplished based on relatively few electronic control units (ECU:s). Therefore, the vehicle into which the present control system is integrated preferably includes a number of ECU:s that are connected to a network in such a manner that the resources from two or more ECU:s can be combined to provide an over-all flexible and efficient vehicular design. Hence, the vehicle may include a network 140, e.g. represented by a CAN, and the control unit 130 is preferably included in, or represented by, an ECU.

As discussed above, it is important to remember that the above- mentioned status signals s<_\ and S₂ merely constitutes examples of status signals usable according to the invention. The status of a theft alarm system, the central lock status, the seat belt status, the lights statuses and the parking brake status represent other examples of alternative, or complementary applicable status signals S_n.

According to one embodiment of the invention, a computer readable medium 135 is also included in the control system. This medium 135 is for example represented by a memory module and has a program product recorded thereon, where the program product is adapted to make the control unit 130 control the above-described procedure. The computer readable medium 135 is either included in the control unit 130, or associated with this unit, such that for instance the control unit 130 may access the medium 135 via an interface.

Figure 3 shows a motor vehicle 200 equipped with the proposed power control system. The vehicle 200 includes a set of electrically powered components C1 , C2, ... , Cm, which are powered by a main power source 1 10. A main power switch 120 is further configured to selectively enable or disable the supply of electric power from the main power source 1 10 to the components C1 , C2, ... , Cm. An ignition switch 125 is also configured to selectively enable or disable the supply of electric power from the main power source 1 10 to a subset of the components C1 , C2, ... , Cm. The ignition switch 125 is arranged in series with the main power switch 120, such that the subset is exclusively powered if both the main power switch 120 and the ignition switch 125 are positioned in an active state. A control unit 130 is arranged to control the power supply to the components C1 , C2, ... , Cm based on the positionings of the switches 120 and 125 and a number of status signals s-i , S₂, ... , S_n according to what has been described above with reference to Figures 1 , 2a, 2b and 2c, such that an adaptive down-powering of the vehicle 200 is attained.

In order to sum up, the general method of controlling the power supply in a motor vehicle will be described below with reference to the flow diagram in figure 4.

A step 410 receives indications of the current states of the main power switch and the ignition switch respectively, i.e. informa- tion pertaining to whether or not the switches are inactive (to prevent power supply from the vehicle's main power source) or active (to enable power supply from the vehicle's main power source). A step 420 receives a number of status signals reflecting the conditions for a given set of functions in the vehicle which are deemed relevant for determining an adequate power- down scenario. Preferably, steps 410 and 420 are executed essentially in parallel with one another.

Then, after completing steps 410 and 420, a step 430 investigates whether or not the main power and ignition switches indicate vehicle shut down. If not, the procedure loops back to steps 410 and 420. Otherwise, a step 440 selects a power-down scenario based on the main power and ignition switch states and the status signals received in step 420. Finally a step 450 produces a set of control signals which are adapted to cause a powering down of the vehicle that is consistent with the selected power- down scenario. Since the power-down scenarios may include a stand-by mode from which the vehicle can be powered up again, the procedure need not necessarily end after step 450. This is illustrated in by means of a dotted arrow back to steps 410 and 420. All of the process steps, as well as any sub-sequence of steps, described with reference to the figure 4 above may be controlled by means of a programmed computer apparatus. Moreover, although the embodiments of the invention described above with reference to the drawings comprise computer apparatus and processes performed in computer apparatus, the invention thus also extends to computer programs, particularly computer programs on or in a carrier, adapted for putting the invention into practice. The program may be in the form of source code; object code, a code intermediate source and object code such as in partially compiled form, or in any other form suitable for use in the implementation of the process according to the invention. The carrier may be any entity or device capable of carrying the program. For example, the carrier may comprise a storage medium, such as a Flash memory, a ROM (Read Only Memory), for example a CD (Compact Disc) or a semiconductor ROM, an EPROM (Erasable Programmable Read-Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), or a magnetic recording medium, for example a floppy disc or hard disc. Further, the carrier may be a transmissible carrier such as an electrical or optical signal which may be conveyed via electrical or optical cable or by radio or by other means. When the program is embodied in a signal which may be conveyed directly by a cable or other device or means, the carrier may be constituted by such cable or device or means. Alternatively, the carrier may be an integrated circuit in which the program is embedded, the integrated circuit being adapted for performing, or for use in the performance of, the relevant processes.

The invention is not restricted to the described embodiments in the figures, but may be varied freely within the scope of the claims.

Claims

1 . A power control system for a motor vehicle comprising: a main power source (1 10) configured to supply electric power to a set of components (C1 , C2, ... , Cm) in the vehicle, a main power switch (120) configured to selectively enable or disable the supply of electric power from the main power source (1 10) to the set of components (C1 , C2, ... , Cm), an ignition switch (125) configured to selectively enable or disable the supply of electric power from the main power source (1 10) to a subset (C1 , C2, ... , Ck) of the set of components (C1 ,

C2, ... , Cm), the ignition switch (125) being arranged in series with the main power switch (120) such that the subset (C1 , C2,

... , Ck) is powered exclusively if both the main power switch

(120) and the ignition switch (125) are positioned in an active state, a control unit (130) configured to receive a respective indication (131 , 132) of whether the main power switch (120) and the ignition switch (125) are positioned in an active state or an inactive state, and based thereon control the supply of power from the main power source (1 10) to the set of components (C1 , C2, ... , Cm), characterized in that the control unit (130) is further adapted to: receive a number of status signals (s-i , S₂, ..., S_n) reflecting conditions for a given set of functions in the vehicle, select one scenario from a group of power-down scenarios based on the status signals (S₁ , S₂, ... , S_n), and produce a set of control signals (CtrM ) adapted to cause a powering down of the vehicle which is consistent with the selected scenario.

2. The system according to claim 1 , wherein the group of power-down scenarios includes: a stand-by scenario wherein electric power is continued to be supplied to at least one component in the set of components (C1 , C2, ... , Cm) during a delay interval (T_D), a fast power-down scenario wherein the supply of electric power to the set of components (C1 , C2, ... , Cm) is discontinued as soon as possible while minimizing the risk that the components take damage, and an emergency power-down scenario wherei n the supply of electric power to the set of components (C1 , C2, ... , Cm) is dis- continued immediately.

3. The system according to claim 2, wherein the control unit (130) is adapted to select the stand-by scenario if: the main power switch (120) is positioned in the active state, the ignition switch (125) is positioned in the inactive state, and a first status signal (s-i ) of the status signals reflects that at least one door of the vehicle is locked .

4. The system according to claim 3, wherein the control unit (130) is adapted to select the fast power-down scenario if the at least one door remains locked at expiry of the delay interval

5. The system according to any one of the claims 2 to 4, wherein the control unit (130) is adapted to select the fast power- down scenario if the control unit (130) receives the consecutive indications that: the ignition switch (125) is positioned in the inactive state, the main switch (120) is repositioned from the active to the inactive state, and at least one door of the vehicle is locked .

6. The system according to any one of the claims 2 to 5, wherein the control unit (130) is adapted to select the emergency power-down scenario if the control unit (130) receives indications that: an operator is located in a driver's seat of the vehicle, the ignition switch (125) is positioned in the active state, and the main switch (120) is repositioned from the active to the inactive state.

7. The system according to claim 6, wherein the control unit (130) is adapted to receive the indication that the operator is located in the drivers seat by means of at least one of: a status signal (s₂) from a seat-activated switch, a status signal (s₂) from an image recorder configured to repeatedly register image data representing an area in proximity of the seat, and a Doppler- based status signal (s₂) representing a reflected probing signal transmitted towards an area of the seat.

8. A motor vehicle (200) comprising: a set of electrically po- wered components (C1 , C2, ... , Cm), a main power source (1 10) configured to supply electric power to the set of components (C1 , C2, ... , Cm), a main power switch (120) configured to selectively enable or disable the supply of electric power from the main power source (1 10) to the set of components (C1 , C2, ... , Cm), an ignition switch (125) configured to selectively enable or disable the supply of electric power from the main power source (1 10) to a subset (C1 , C2, ... , Ck) of the components (C1 , C2, ... , Cm), the ignition switch (125) being arranged in series with the main power switch (120) such that the subset (C1 , C2, ... , Ck) is exclusively powered if both the main power switch (120) and the ignition switch (125) are positioned in an active state, characterized in that the vehicle (200) comprises the power control system according to any one of the proceeding claims.

9. A method for controlling the power supply in a motor ve- hide having a main power source (1 10) configured to supply electric power to a set of components (C1 , C2, ... , Cm) in the vehicle, a main power switch (120) configured to selectively enable or disable the supply of electric power from the main power source (1 10) to the set of components (C1 , C2, ... , Cm), and an ignition switch (125) configured to selectively enable or disable the supply of electric power from the main power source (1 10) to a subset (C1 , C2, ... , Ck) of the set of components (C1 , C2, ... , Cm), the ignition switch (125) being arranged in series with the main power switch (120) such that the subset (C1 , C2, ... , Ck) is powered exclusively if both the main power switch (120) and the ignition switch (125) are positioned in an active state, the method comprising controlling the supply of power from the main power source (1 10) to the set of components (C1 , C2, ... , Cm) based on a respective indication (131 , 132) of whether the main power switch (120) and the ignition switch (125) are positioned in an active state or an inactive state, characterized by selecting one scenario from a group of power-down scenarios based on a number of status signals (s-i , S₂, ... , S_n) reflecting conditions for a given set of functions in the vehicle, and produci ng a set of control signals (CtrM ) adapted to cause a powering down of the vehicle which is consistent with the se- lected scenario.

10. The method according to claim 9, wherein the group of power-down scenarios includes: a stand-by scenario wherein electric power is continued to be supplied to at least one component in the set of components (C1 , C2, ... , Cm) during a delay interval (T_D), a fast power-down scenario wherein the supply of electric power to the set of components (C1 , C2, ... , Cm) is discontinued as soon as possible while minimizing the risk that the components take damage, and an emergency power-down scenario wherei n the supply of electric power to the set of components (C1 , C2, ... , Cm) is discontinued immediately.

1 1 . The method according to claim 10, comprising selecting the stand-by scenario if: the main power switch (120) is positioned in the active state, the ignition switch (125) is positioned in the inactive state, and a first status signal (s-i ) of the status signals reflects that at least one door of the vehicle is locked .

12. The method according to claim 1 1 , comprising selecting the fast power-down scenario if the at least one door remains locked at expiry of the delay interval (T_D).

13. The method according to any one of the claims 10 to 12, comprising selecting the fast power-down scenario if the control unit (130) receives the consecutive indications that: the ignition switch (125) is positioned in the inactive state, the main switch (120) is repositioned from the active to the inactive state, and at least one door of the vehicle is locked.

14. The method according to any one of the claims 10 to 13, comprising selecting the emergency power-down scenario if the control unit (130) receives indications that: an operator is located in a driver's seat of the vehicle, the ignition switch (125) is positioned in the active state, and the main switch (120) is repositioned from the active to the inactive state.

15. A computer program product loadable into a memory (135) of a computer included in a motor vehicle (200) which is equipped with a main power source (1 10) configured to supply electric power to a set of components (C1 , C2, ... , Cm) in the vehicle, a main power switch (120) configured to selectively enable or disable the supply of electric power from the main power source (1 10) to the set of components (C 1 , C2, ... , Cm), and an ignition switch (125) configured to selectively enable or disable the supply of electric power from the main power source (1 10) to a subset (C1 , C2, ... , Ck) of the set of components (C1 , C2, ... , Cm), the ignition switch (125) being arranged in series with the main power switch (120) such that the subset (C1 , C2, ... , Ck) is exclusively powered if both the main power switch (120) and the ignition switch (125) are positioned in an active state, the computer program product comprising software adapted to cause the computer to control the steps of any of the claims 9 to 14 when the program product is run on the computer.

16. The computer program product according to claim 15, wherein the program product is recorded onto a carrier.