Patent ID: 12208755

As has been mentioned, the invention is implemented in the context of an electric or hybrid motor vehicle, with power supply means which are particular in that they make a long range of the vehicle possible by using two different power sources, and this invention relates to the particular arrangement of safety means of these two different power sources, in particular in that safety means6shared by the two power sources3,4are provided and housed, in the vicinity of these sources, in a fluid-tight housing2, within an electric power supply device1which will be described in more detail below.

FIG.1schematically shows the integration of such an electric power supply device1into one exemplary arrangement providing, in particular, a drive of a hybrid or electric vehicle, that is to say comprising at least one voltage network9which is able to supply power to an electric motor. The voltage network of the vehicle may be supplied with power by a first power source3and/or by a second power source4. According to the example illustrated inFIG.1, the first power source3is an electric battery, while the second power source4is a fuel cell. The two power sources are able at least to transmit electrical energy to the voltage network9in order to provide the drive of the vehicle.

The first power source3may therefore be in the form of an electric battery which is able to deliver the previously stored electrical energy on demand. When the first power source3delivers an electric current intended to supply power to the voltage network9, said electric current flows within the first set of electrical wires11which is connected to the first power source3, as far as an electrical junction14. “Set of electrical wires” should be understood to mean one or more electrical wires within which an electric current is able to flow. In the illustrated embodiment, and without this actually limiting the invention, the first set of electrical wires11, as well as the sets of electrical wires described below, comprise a positive current wire and a ground wire.

In the event that the second power source4is a fuel cell, it produces electrical energy through combustion. More specifically, a chemical reaction occurs between a fuel, for example dihydrogen flowing within the dihydrogen circuit50, and oxygen which may be guided as far as the second power source4via an air circuit56.

The dihydrogen is drawn from a dihydrogen tank51and is made to flow by means of a first pump52as far as the second power source. In the air circuit56, a compressor57causes the air to flow as far as the second power source4. The chemical reaction which occurs between the dihydrogen and the air thus makes it possible to generate electrical energy. As such a chemical reaction may give off heat, a cooling circuit53flows partially within the second power source4in order to maintain a low enough temperature not to cause a malfunction. The cooling circuit53comprises a second pump55making it possible to make a cooling fluid, for example glycol water, flow, as well as a heat exchanger54which makes it possible to discharge the heat energy of the cooling fluid after the latter has accumulated it by passing through the second power source4.

The second power source4is connected to a second set of electrical wires12. The electrical energy generated by the second power source4and leaving the latter therefore flows initially within the second set of electrical wires12and passes through an electric converter7. The electric converter7is a DC-to-DC converter which makes it possible to convert the electric current generated by the second power source4into a DC electric current adapted to the voltage of the electric current delivered by the first power source3.

The second set of electrical wires12extends, like the first set of electrical wires11, from the power source which is associated with it as far as the electrical junction14. It should be noted that the electrical junction14is configured so that the electric current flowing within the second set of electric wires12as far as the electrical junction14after having been converted by the electric converter7may then flow within the first set of electrical wires11in the direction of the first power source3, with the aim of recharging this first power source3. It is therefore understood that the second power source may, according to a first operating mode, supply electric current to the voltage network of the vehicle and the electric motor of the latter and may, according to a second embodiment, supply electric current to the first power source for recharging purposes.

The electric current may also flow within a third set of electric wires13extending from the electrical junction14and making it possible to guide the electric current generated by the operation of the first power source and/or by the operation of the second power source as far as the voltage network9. The third set of electrical wires13is therefore shared by the two power sources. As has been described above, the two power sources may be used to supply power to the voltage network9. The electric current emanating from one or other of the power sources may therefore flow within the third set of electrical wires13once it has arrived at the electrical junction14.

In the example illustrated inFIG.1, the third set of electrical wires13makes the electric current flow as far as a first auxiliary converter62, which is a DC-to-AC converter, thereby supply an AC electric current to the voltage network9.

In addition, a recharge port61is connected to the electrical junction14and makes it possible, for example, to recharge the first power source3through electrical connection when the vehicle is stationary.

The first power source3may also be configured to supply power to an auxiliary battery64. The latter makes it possible, for example, to supply power to the lighting of a passenger compartment of the vehicle or any other function requiring an injection of electrical energy with the exception of the power supply of the voltage network9. The voltage network9which may supply power to the electric motor, in which the current flows at a high voltage which may be about 400 V, may thus be distinguished from a low-voltage, for example about 12 V, auxiliary network supplied with power by the auxiliary battery. The auxiliary battery64is connected to the first power source3via a pair of auxiliary electrical wires16. In order to adapt the electric current to the energy needs of the elements supplied with power by the auxiliary battery64, a second auxiliary converter63is arranged on the pair of auxiliary electrical wires16, between the first power source3and the auxiliary battery64. The second auxiliary converter63is a DC-to-DC converter.

The electric power supply device1according to the invention, shown with dotted lines inFIG.1, will now be described in more detail, in particular with reference toFIG.2.

More particularly, the electric power supply device1comprises the first power source3, the second power source4, the electric converter7, the first set of electrical wires11, the second set of electrical wires12, the third set of electrical wires13and the electrical junction14, which are mentioned inFIG.1.

The electric power supply device1also comprises a metal housing2which is shown inFIG.2with dotted lines, and contains at least the set of elements which is listed above. The metal housing makes it possible, in particular, to centralize the elements of the electric power supply device1within the same fluid-tight chamber, connected to the ground of the vehicle.

The arrangement of the two power sources, of the first set of electrical wires11and of the second set of electrical wires12is identical to what has been described above. It is possible to observe, at the first power source3, that the pair of auxiliary electrical wires16passes through the metal housing2so that the auxiliary battery64which is visible inFIG.1extends outside the metal housing. The latter is arranged so as to allow the pair of auxiliary electrical wires16to leave. The same goes for a dihydrogen inlet501, for a dihydrogen outlet502, for an air inlet561and for an air outlet562which pass through the metal housing in order to form a connection with the second power source4. Thus, it should be noted that, in the case of a second power source formed by a fuel cell, the rest of the components contributing to forming the fuel cell assembly, among which the hydrogen supply system or the cooling system, are not housed in the metal housing and do not here form part of the electric power supply device1within the meaning of the invention.

Safety means6, which are shared by the two power sources3,4, are arranged on the third set of electrical wires13. The electric power supply device1comprises a control module5authorized to control these safety means6. The safety means6make it possible to interrupt the operation of the electric power supply device1by cutting off the flow of the electric current through the third set of electrical wires13. As the latter is shared by the two power sources as mentioned above, arranging the safety means6therein thus makes it possible to share the safety means of the device according to the invention, so that controlling these safety means6makes it possible to interrupt the operation of the two power source simultaneously in a single action. This interruption of the operation of the electric power supply device1by the safety means6therefore occurs faster than in a configuration where the two power sources each possess their own safety means, which must be managed independently of one another.

The control module5is able to send a command to the safety means6indicating that the flow of electric current within the third set of electrical wires13must be interrupted. The sending of this command may, for example, be a consequence of the receipt and/or the detection of an abnormal datum by the control module5as will be described below. As the abnormal datum may be indicative of a malfunction of the electric power supply device1or of an incident which may cause damage, the function of the safety means6controlled by the control module5may be preventative or indeed consist in limiting the incidence of potential damage arising following the malfunction of the electric power supply device1.

The control module5and the safety means6are also included within the metal housing2. The latter is fluid-tight in order to avoid an incident initiated within the metal housing2, for example a fire starting, propagating outside the latter.

FIG.3is a detailed schematic representation of an electrical installation of the electric power supply device1and makes it possible to structurally and functionally detail the control module5, the safety means6and the interactions between them.

InFIG.3, the safety means6are schematically shown by a rectangle with dotted lines, the elements included within said rectangle being all or part of one of the safety means6. In the illustrated example, the safety means6are in an open position, that is to say that they are in a position such that the electric current can no longer flow within the third set of electrical wires13or in the whole of the electrical installation of the electric power supply device1. Such a configuration may, for example, be due to the activation of said safety means6. It is understood that, when the electric power supply device1is operating normally, with, in particular, a normal flow of current going from one and/or the other of the power sources toward an output connected to the voltage network of the vehicle, the safety means are controlled so as to be closed and be electrically continuous with the electrical wires of the third set13.

FIG.3contributes additional structural features connected with the metal housing2. It is, in particular, possible to observe that the metal housing comprises a connection to earth8. The connection to earth8may, for example, be indirect, by placing the metal housing2within a chassis of the vehicle. The connection to earth8makes it possible to discharge any electrical energy which may have propagated in the structure of the metal housing2.

The electric power supply device1also comprises a connector10, which is not included within the metal housing2. The connector10is arranged against an external wall of the metal housing2and is connected to the third set of electrical wires13. The connector10is configured to be connected to the voltage network of the vehicle9, thereby making it possible to direct the electric current generated by each power source toward said voltage network, as is shown inFIG.1. In order to provide the connection between the third set of electrical wires13and the connector10, the metal housing2may, for example, be configured to allow the third set of electrical wires13to pass through its structure.

The safety means6comprise at least one electrical relay arranged in the metal housing2on a portion of the electrical network shared by the two power sources, and more particularly on the portion of the network between the electrical junction14and the connector10. In the example illustrated inFIG.3, the safety means comprise two electrical relays22controlled simultaneously by the control module, each of the two electrical relays22being arranged on one of the two wires in the third set of electrical wires13. It is, however, possible to integrate only a single electrical relay22depending on the configuration of the third set of electrical wires13. The electrical relays22allow the electric current to flow when they are in a closed position, and cut off said flow when they are in an open position, as is illustrated inFIG.3.

Operating safety, via the interruption of the flow of the electric current, may therefore be achieved by opening these electrical relays22, said opening being controlled by the control module5. The latter comprises, in addition, a plurality of means for communication, here wired communication, with several elements of the electric power supply device1. By virtue of these communication means, the control module5may, for example, control an intensity and/or a voltage generated by the first power source3or the second power source4. The control module5may also control the safety means6as has been mentioned.

The control module5is also connected to various measurement and calculation members, among which, here, a temperature sensor20and a member for calculating insulation resistance21. The control module5is configured to receive a value measured or calculated by one of these members, and to compare this value with a corresponding threshold value. This threshold value may, in particular, be stored in a memory of the control module. The control module carries out the instructions for controlling the safety means and, for example, opens or does not open the relays, depending on the result of the comparison with respect to these threshold values.

The temperature sensor20measures the temperature within the metal housing2and transmits said measurement to the control module5. The measurement of the temperature is useful, for example, in the event of a fire starting within the metal housing2, which will increase the temperature abnormally. The control module5may thus be parametrized so as to open the electrical relays22after having received a temperature measurement which is above a maximum threshold temperature, said threshold corresponding to a temperature beyond which the temperature measurement is abnormal.

The member for calculating insulation resistance21is connected to the metal housing2and makes it possible to measure the insulation resistance of the latter. The member for calculating insulation resistance21may, in particular, send an electric current through a circuit including the metal housing and measure the intensity of the electric current which returns to it, in order to deduce therefrom an insulation resistance value for the metal housing2. The decrease of the insulation resistance of the metal housing2, which may, for example, be due to wear over time or indeed result from a malfunction of the electric power supply device1, attests to a risk of current leakage and a danger to the occupants of the vehicle. Also, too low an insulation resistance may, for example, cause electrical damage to an element of the vehicle which is external to the electric power supply device1, as the metal housing2no longer guarantees electrical insulation. The control module5may then be configured to open the electrical relays22after having received an insulation resistance value which is below a minimum insulation resistance threshold.

The safety means6also comprise a pre-charge relay23arranged in parallel with one of the electrical relays22, and more particularly on the positive electrical wire. The pre-charge relay23, which is associated with a resistor, makes it possible to gradually increase the electric current flowing within the third set of electrical wires13, for example when the vehicle is started. The pre-charge relay23is thus a safeguard against the flow of an electric current which is too intense. Just like the electrical relays22, the pre-charge relay23is shared by the two power sources, here being arranged on the third set of electrical wires, and it is controlled by a command of the control module5.

The safety means6shared by the two power sources according to the invention may also comprise a manual electrical decoupler24, which comprises a manual actuator25which is accessible from outside the metal housing2. The manual electrical decoupler24also makes it possible to interrupt the flow of the electric current within the third set of electrical wires13, that is to say on the portion of the electrical circuit shared by the two power sources, via one or more switches arranged inside the housing and connected to the manual actuator24. The manual electrical decoupler24is an additional safeguard, for example in the event of a malfunction of the control module5. The manual actuator25may be actuated by a third party, for example during an intervention by the emergency services following an accident.

In order to avoid short-circuit phenomena, the electric power supply device1also comprises a first passive safety member26, a second passive safety member27and a third passive safety member28, which are arranged on the first set of electrical wires11, the second set of electrical wires12and the third set of electrical wires13, respectively. Each of the passive safety members is able to trigger automatically in order to cut off the flow of the electric current in the set of electrical wires which belongs to it. The passive safety members therefore differ from the safety means6which are controlled by the control module.

In order for the control module5to be able to manage and adapt the flow of the electric current as well as the intensity and the voltage of the latter, the sets of electrical wires comprise several electrical intensity sensors31,32,33. A first electrical intensity sensor31is arranged on the second set of electrical wires12between the second power source4and the electric converter7, a second electrical intensity sensor32is arranged on the second set of electrical wires12between the electric converter7and the electrical junction14, and a third electrical intensity sensor33is arranged on the first set of electrical wires11between the first power source3and the electrical junction14. In addition, voltage sensors34,35,36,37are arranged on the second set of electrical wires12between the second power source4and the electric converter7and between the electric converter7and the electrical junction14, as well as on the third set of electrical wires13between the electrical junction14and the safety means6and between the safety means6and the connector10, respectively.

The set of measurements made by the activated sensors is transmitted to the control module5, which may then adapt, via the aforementioned, in particular wired, communication means, the operation of the power sources or of the electric converter7. Said measurements may also be an indicator which may lead the electrical relays22to open as a safety measure.

By way of non-limiting example, the intensity measurements made by the electrical intensity sensors31,32,33may serve to detect a current of an intensity with a value which is higher than the control values, but well below the thresholds for triggering the passive safety members26,27,28, and the control module5may then generate a suitable control instruction. For example, a runaway of the charge of the electric converter7following a control problem may be detected by the first electrical intensity sensor31and this detection may make it possible for the control module5to generate an instruction relating to stopping the second power source4, for example by extinguishing the supply of hydrogen and opening the relays. The third electrical intensity sensor33may in the same way detect a current for charging the first power source3by means of the second power source4which is too high and which requires the second power source4and/or the electric converter7to be stopped. Equivalently, the monitoring of the voltages by the voltage sensors34,35,36,37makes it possible to detect a problem of local overvoltage outside the ranges of normal operation, and in the same way control the operation of the power sources3,4, of the electrical energy converter7and, if necessary, of the safety means6.

Of course, the invention is not limited to the examples which have just been described and many modifications may be made to these examples without departing from the scope of the invention, as long as the invention, as it has just been described, proposes an electric power supply device comprising at least two different power sources and safety means shared by said power sources.