Electrical power supply system for vehicle

Abstract

The invention relates to a method for managing the use of an on-board charger for a battery of a motor vehicle, the vehicle comprising a power supply battery, the on-board charger being connected on the one hand to said battery and on the other hand to be connected to an electrical power supply network external to the vehicle capable of providing a three-phase voltage, the invention relates to an on-board charger comprising a plurality of conversion modules (E1, E2, E3), each conversion module (E1, E2, E3) comprising a plurality of basic power conversion units (A, B, C, D, E, F, G, H, I) independent of one another, each basic unit (A, B, C, D, E, F, G, H, I) being characterized by a maximum threshold value of the used power, each conversion module (E1, E2, E3) being intended to be connected to a phase of an external power supply network.

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of electric or hybrid vehicles, and more precisely to a method for managing the use of different charging modules of an on-board charger of a motor vehicle. BACKGROUND

[0002] In a known manner, an electric or hybrid vehicle comprises an on-board charger which allows the repeated charging of one or more batteries of the vehicle. More precisely, the on-board charger comprises a power factor corrector, more generally known under the name PFC (for "Power Factor Corrector" in English), which allows the regulation of the output voltage of the on-board charger.

[0003] The power factor corrector PFC comprises three power conversion modules. Furthermore, each conversion module comprises a plurality of elementary power conversion cells independent of one another. Each elementary cell is more generally referred to as a "bank" by the person skilled in the art.

[0004] Each conversion module is intended to be connected to one phase of an electrical power supply network external to the vehicle. The number of elementary power conversion cells activated for a given conversion module depends on the power required by the battery for the repeated charging of this battery. In this case, the activation order of the elementary cells is predefined. As a consequence of this, the elementary cells of each conversion module of the power factor corrector PFC are not used uniformly. In other words, by extension, each elementary cell ages differently and therefore the set of elementary conversion cells no longer wears out uniformly.

[0005] There is therefore a need for a solution which allows at least partially overcoming the drawbacks described previously. SUMMARY

[0006] To this end, the present invention relates to a method for managing the use of an on-board charger of a battery of a motor vehicle, the vehicle comprising an electrical power supply battery, the on-board charger being connected on the one hand to said battery and on the other hand intended to be connected to an electrical power supply network external to the vehicle capable of providing a three-phase voltage, each phase of the network being characterized by a maximum total use power, the on-board charger comprising a plurality of conversion modules, each conversion module comprising a plurality of elementary power conversion cells independent of one another, each elementary cell being characterized by a maximum threshold of use power, each conversion module being intended to be connected to one phase of the external power supply network, said method comprising the steps consisting in: a) determining the electrical energy which has passed through each elementary cell since the beginning of the use of said elementary cell, b) determining an activation order of the elementary cells by ordering the various elementary cells from the elementary cell which has passed through the least electrical energy to the elementary cell which has passed through the most electrical energy, c) determining a power value to be provided by each conversion module based on the voltage that each phase of the electrical power supply network is able to provide and the maximum total used power of each phase of the network, d) attributing to each elementary unit of the previously determined list a maximum power value based on: i) the determined activation order, ii) the maximum threshold of used power of each elementary unit, iii) the maximum total used power of each phase of the network, e) determining the instantaneous total power that the on-board charger should provide, f) activating the elementary units based on: i) the power attributed to each elementary unit, ii) the instantaneous total power that the on-board charger should provide.

[0007] The method thus proposed allows adapting the power used by the on-board charger based on the power that each phase of the network is able to provide. Furthermore, the method also allows sharing the aging of the elementary units by using first the elementary units that are the least used, since they are the ones with the least power. Thus, it is not always the same elementary units that are used.

[0008] Preferably, during the attribution step, the power attributed to each elementary unit is defined as follows: for each elementary unit and in the activation order of the elementary units, the attributed power is: a) equal to the difference between the maximum total used power of the phase to which said conversion module is connected and the sum of the powers attributed to the other elementary units of the same conversion module, b) and is defined so as to be less than or equal to the maximum threshold of used power.

[0009] In this way, the power attributed to each elementary unit depends on the use limits and thresholds of each elementary unit and on the power that each phase of the network is able to provide.

[0010] Also preferably, during the activation step, the selection of the elementary units to activate is achieved by selecting, in the activation order, the least number of elementary units for which the sum of the attributed maximum powers is greater than or equal to the instantaneous power.

[0011] Thus, the elementary units are not activated systematically, but the elementary units are activated when it is necessary to provide the instantaneous power that is required.

[0012] The application also relates to a power supply system for a motor vehicle comprising: a) a power supply battery, b) an on-board charger connected on one hand to the battery and on the other hand intended to be connected to an electrical power supply network external to the vehicle, able to provide a three-phase voltage, each phase of the network being characterized by a maximum total power used, the on-board charger comprising a plurality of conversion modules, each conversion module comprising a plurality of elementary power conversion units independent of one another, each elementary unit being characterized by a maximum threshold of power used, each conversion module being intended to be connected to one phase of the external power supply network, c) a control unit able to implement the method as previously proposed.

[0013] Finally, the invention relates to a motor vehicle comprising a power supply system as previously proposed. BRIEF DESCRIPTION OF DRAWINGS

[0014] Other features and advantages of the invention will become more apparent on reading the following description. The description is purely illustrative and should be read in conjunction with the appended drawings in which: [ Figure 1 ] Figure 1 is a schematic representation of an on-board charger according to the invention.

[0015] [ Figure 2 ] Figure 2 is a schematic representation of a method for managing the use of an on-board charger according to the invention, and more precisely for managing the activation of the elementary units of the power factor corrector of an on-board charger according to the invention. Figure 1 Figure 1

[0016] [ Figure 3 ] Figure 3 The activation order of the elementary units A, B, C, D, E, F, G, H, I obtained after the determination step S2 of the method according to the invention is represented in the table. Figure 2

[0017] [ Figure 4 ] Figure 4 The power provided by each phase of the electrical power supply network to each conversion module of the power factor corrector of the on-board charger according to the invention is represented in the table. Figure 1

[0018] [ Figure 5 ] Figure 5 The maximum power imparted to each elementary unit A, B, C, D, E, F, G, H, I of the power factor corrector of the on-board charger according to the invention is represented in the table. Figure 1 DETAILED DESCRIPTION

[0019] ​​​​​In a usual manner, the vehicle comprises an electrical battery configured to power various electrical devices of the vehicle. In order to repeatedly charge said electrical battery, the vehicle comprises an on-board charger.

[0020] More precisely, the on-board charger comprises a power factor corrector, more generally called PFC (for "Power Factor Corrector" in English), and a control unit.

[0021] With reference to Figure 1 , the power factor corrector 1 of the on-board charger is intended to be electrically connected to a repeated charging terminal B10 external to the vehicle. The repeated charging terminal B10 is connected to an electrical power supply network external to the vehicle. The external power supply network corresponds to a three-phase voltage, each phase of said voltage not being forced to provide the same level of voltage. In other words, the power provided by each of the phases is limited by a maximum total used power P max . For example, the first phase can provide 8 kW, the second phase cannot provide any power (0 kW) and the third phase can provide 6 kW.

[0022] The power factor corrector 1 allows to convert the voltage provided by said network to the repeated charging terminal B10 in order to repeatedly charge the battery of the vehicle.

[0023] In an accurate manner, the type of repeated charging terminal presented here can be known by the person skilled in the art under the name "EVSE" (for "Electrical Vehicle Supply Equipment" in English).

[0024] To this end, the power factor corrector 1 comprises a plurality of power conversion modules, in other words a plurality of stages. According to Figure 1 the example presented in the description, the corrector comprises three power conversion modules E1, E2, E3. Each power conversion module E1, E2, E3 is intended to be connected to one phase of the voltage provided by the power supply network.

[0025] Each power conversion module E1, E2, E3 comprises a plurality of elementary power conversion units A, B, C, D, E, F, G, H, I, generally called "bank" by the person skilled in the art and independent from each other. According to the example presented here, each conversion module E1, E2, E3 comprises three elementary units. The first conversion module E1, intended to be connected to the first phase of the external electrical power supply network, comprises three elementary units A, B, C, the second stage E2, intended to be connected to the second phase of the external electrical power supply network, comprises three elementary units D, E, F and the third stage E3, intended to be connected to the third phase of the external electrical power supply network, comprises three elementary units G, H, I.

[0026] Each elementary unit A, B, C, D, E, F, G, H, I is provided with a maximum threshold S max of use of power. In a usual manner, the maximum threshold S max of use of power is the same for all elementary units A, B, C, D, E, F, G, H, I. By way of example, the maximum threshold S max of use of power is equal to 3.6 kW for each elementary unit A, B, C, D, E, F, G, H, I.

[0027] The control unit, indicated by the reference number 40, is connected to each elementary unit A, B, C, D, E, F, G, H, I and is able to command each elementary unit A, B, C, D, E, F, G, H, I. More precisely, the control unit is configured to define which of the elementary units A, B, C, D, E, F, G, H, I of each conversion module E1, E2, E3 is to be activated and the power provided by each of the activated elementary units A, B, C, D, E, F, G, H, I.

[0028] The control unit 40 is also configured to obtain, in other words to recover, the value of the maximum total use power P max of each phase of the recurrent charging terminal B10.

[0029] More precisely, the control unit 40 is configured to: a. determine, for each elementary unit A, B, C, D, E, F, G, H, I, the electrical energy that has passed through said elementary unit A, B, C, D, E, F, G, H, I during the duration of the life of said elementary unit A, B, C, D, E, F, G, H, I, b. determine the activation order of the elementary units A, B, C, D, E, F, G, H, I by ordering the elementary units from the elementary unit through which the least electrical energy has passed to the elementary unit through which the most electrical energy has passed, each elementary unit A, B, C, D, E, F, G, H, I thus being associated with a rank, c. determine the power value to be provided by each conversion module E1, E2, E3 on the basis of the maximum total use power P max of each phase of the electrical power supply network and of the voltage provided by each phase of the recurrent charging terminal B10, d. assign to each elementary unit A, B, C, D, E, F, G, H, I in the list previously determined the power value to be provided on the basis of: i. the activation order determined, ii. the maximum threshold S max of use of power of each elementary unit A, B, C, D, E, F, G, H, I, iii. the power value to be provided by each conversion module E1, E2, E3.

[0030] Based on the power imparted to each elementary unit A, B, C, D, E, F, G, H, I and on the instantaneous consumption (in other words, the power) consumed by the vehicle battery, the control unit 40 is configured to manipulate the activation or non-activation of the elementary units A, B, C, D, E, F, G, H, I. This will be explained in more detail in the description of the method below.

[0031] Method Reference Figures 2 to 5 The method according to the application will now be presented in detail, as described previously, for managing the use of the on-board charger. In particular, the method according to the application is described in the case where the repeated charging terminal B10 is connected to the power factor corrector. The method is implemented by the control unit 40 as described previously. Figure 2

[0032] To this end, during a preliminary step SO, each phase of the repeated charging terminal B10 is connected beforehand to a conversion module E1, E2, E3.

[0033] The method first comprises a step of determining SI the amount of electrical energy that has passed through each elementary unit A, B, C, D, E, F, G, H, I during the lifetime of each elementary unit.

[0034] To this end, voltage measurements and current measurements are performed in order to determine, for each elementary unit A, B, C, D, E, F, G, H, I, the power in kilojoules. The set of measurements can be received by the control unit 40 or measured directly.

[0035] The method then comprises a step of determining S2 the activation order of the elementary units A, B, C, D, E, F, G, H, I by ranking the respective elementary units A, B, C, D, E, F, G, H, I from the elementary unit that has passed the least electrical energy (rank 1 ) to the elementary unit that has passed the most electrical energy (rank 9). Reference is made to Figure 3 The activation order (in other words, the rank) associated with each elementary unit A, B, C, D, E, F, G, H, I obtained after the step of determining S2 is represented in the table. This step thus allows the creation of an activation list of the elementary units A, B, C, D, E, F, G, H, I based on the energy passed through each elementary unit A, B, C, D, E, F, G, H, I.

[0036] The method also comprises a step of determining S3 the power value to be provided by each conversion module E1, E2, E3, according to the maximum total use power P max The power value to be provided by each conversion module E1, E2, E3 is determined S3. Indeed, in this case, each phase of the repeated charging terminal B10 does not provide the same power. Thus, reference is made to​Figure 4 It can be determined for example that the first conversion module E1 obtains a maximum of 8 kW from the first phase of the repeated charging terminal B10, that the second conversion module E2 does not obtain any power from the second phase of the repeated charging terminal B10 and that the third conversion module E3 obtains a maximum of 6 kW from the third phase of the repeated charging terminal B10.

[0037] The method then comprises a step of attributing S4 to each conversion unit A, B, C, D, E, F, G, H, I of the list previously determined a maximum power value based on: a. the activation order in the list, b. the maximum threshold of the used power S of each elementary unit A, B, C, D, E, F, G, H, I max , c. the power value provided by each phase to its own conversion module E1, E2, E3 (in other words, the maximum total used power P max of each phase of the voltage provided by the repeated charging terminal B10).

[0038] First, the step of attributing S4 comprises an initialization step during which the set of attributed power values is limited to 0 kW.

[0039] Then, the power attributed to each elementary unit A, B, C, D, E, F, G, H, I is limited in the following way: for each elementary unit A, B, C, D, E, F, G, H, I and according to the determined order of activation of the elementary units A, B, C, D, E, F, G, H, I, the maximum power attributed: a. is equal to the difference between the value of the maximum total used power P max of the phase connected to said conversion module E1, E2, E3 and the sum of the powers attributed to the other elementary units A, B, C, D, E, F, G, H, I of the same conversion module E1, E2, E3, b. and is limited so as to be less than or equal to the maximum threshold of the used power S max .

[0040] With reference to Figure 5 , the maximum power attributed to each elementary unit A, B, C, D, E, F, G, H, I is represented.

[0041] In particular, here, since the second phase of the power supply network does not provide power to the second conversion module E2, the power attributed to each elementary unit D, E, F of the second conversion module E2 remains at the value attributed during the preliminary initialization step S0, in other words: 0 kW.

[0042] The maximum power assigned to said elementary unit H is then equal to the maximum threshold S max and therefore equal to 3.6 kW in the example presented here.

[0043] The maximum power assigned to said elementary unit H is then equal to the maximum threshold S max and therefore equal to 3.6 kW in the example presented here.

[0044] Subsequently, the maximum assigned power of the elementary unit I (ranked 4 in the activation) is calculated by performing the following calculation: 6 kW - 3.6 kW - 0 kW = 2.4 kW.

[0045] The maximum assigned power of the elementary unit G (ranked 7 in the activation) is then calculated by performing the following calculation (the charging modules E and D are ranked 5 and 6 in the activation, but their assigned power has already been limited to 0 kW): 6 kW - 3.6 kW - 2.4 kW = 0 kW. In other words, the elementary units H and I have together provided the maximum power available for the third conversion module E3.

[0046] The maximum power assigned to the elementary unit B (ranked 8 in the activation) is then determined by performing the following calculation: 8 kW - 3.6 kW - 0 kW = 4.4 kW. However, the maximum assigned power should be less than or equal to the maximum threshold S max and therefore less than or equal to 3.6 kW. The maximum power assigned to the elementary unit B is therefore limited to 3.6 kW.

[0047] Finally, the maximum assigned power for the elementary unit A (ranked 9 in the activation) is determined, for which the maximum assigned power is calculated in the following manner: 8 kW - 3.6 kW - 3.6 kW = 0.8 kW.

[0048] The method then comprises the following steps: activating S5 the charging modules A, B, C, D, E, F, G, H, I based on: a. the maximum power assigned to each elementary unit A, B, C, D, E, F, G, H, I, b. the instantaneous power corresponding to the power consumed by the battery of the vehicle, in other words the power that should be provided by the power factor corrector PFC to compensate for the battery consumption.

[0049] More precisely, during the step of activation S5, only some elementary units A, B, C, D, E, F, G, H, I are activated. The selection of the elementary units A, B, C, D, E, F, G, H, I to activate is achieved by selecting the minimum number of elementary units A, B, C, D, E, F, G, H, I to which the sum of the power assigned is greater than or equal to the instantaneous power, in accordance with the activation order.

[0050] For example, if the instantaneous power is equal to 8 kW, the elementary units A, B, C, D, E, F, G, H, I to activate will correspond to the elementary units H, C and I (since the sum of the maximum power assigned to these elementary units is equal to 9.6 kW).

[0051] For another example, if the instantaneous power is equal to 10 kW, the activation of the elementary units H, C and I will not be sufficient. The next elementary unit in the activation list will also have to be activated: here, the elementary unit B (for which the maximum power assigned is 3.6 kW).

[0052] The maximum power assignment for each elementary unit A, B, C, D, E, F, G, H, I thus depends on the power already passed through each elementary unit A, B, C, D, E, F, G, H, I. The power already passed through each elementary unit A, B, C, D, E, F, G, H, I allows to represent the "age" of each elementary unit A, B, C, D, E, F, G, H, I (in other words, the usage rate). The activation of each elementary unit A, B, C, D, E, F, G, H, I thus depends on the age of each elementary unit A, B, C, D, E, F, G, H, I.

[0053] This thus allows to balance and globally homogenize the usage of the set of elementary units A, B, C, D, E, F, G, H, I. In other words, not always the same elementary units A, B, C, D, E, F, G, H, I are used as required. This allows to avoid premature aging of some or all of the elementary units A, B, C, D, E, F, G, H, I.

Claims

1. A method for managing the use of an on-board charger for a battery of a motor vehicle, the vehicle including a power supply battery, the on-board charger being connected on one side to said battery and on the other side intended to be connected to an electrical power supply network outside the vehicle capable of providing three-phase voltage, each phase of the network being controlled by a maximum total power consumption (P). max The on-board charger is characterized by comprising multiple conversion modules (E1, E2, E3), each of which includes multiple independent basic power conversion units (A, B, C, D, E, F, G, H, I). Each basic unit (A, B, C, D, E, F, G, H, I) is defined by a maximum power threshold (S). max The method, characterized in that each conversion module (E1, E2, E3) is intended to be connected to one phase of an external power supply network, includes the following steps: a) Determine (S1) the electrical energy that has been transmitted through each basic unit (A, B, C, D, E, F, G, H, I) since the start of the use of the basic units (A, B, C, D, E, F, G, H, I). b) The activation order of the basic units (A, B, C, D, E, F, G, H, I) is determined by sorting the basic units (A, B, C, D, E, F, G, H, I) from the basic unit that passes through the least electrical energy to the basic unit that passes through the most electrical energy. c) Based on the voltage that each phase of the electrical power supply network can provide and the maximum total power used by each phase of the network (P) max (S3) determines the power value to be provided by each conversion module (E1, E2, E3). d) Assign (S4) the maximum power value to each basic unit (A, B, C, D, E, F, G, H, I) in the previously determined list based on the following: i) The determined activation order, ii) The maximum threshold power (S) for each basic unit (A, B, C, D, E, F, G, H, I) max ), iii) Maximum total power used by each phase of the network (P) max ), e) Determine the total instantaneous power that the on-board charger should provide. f) Activate the (S5) basic units (A, B, C, D, E, F, G, H, I) based on the following: i) The power assigned to each basic unit (A, B, C, D, E, F, G, H, I), ii) The total instantaneous power that the on-board charger should provide.

2. The method as claimed in the preceding claim, wherein during the assignment step, the power assigned to each basic unit (A, B, C, D, E, F, G, H, I) is defined as follows: the power assigned to each basic unit (A, B, C, D, E, F, G, H, I) and in accordance with the activation order of the basic units (A, B, C, D, E, F, G, H, I) is: a) Equal to the maximum total power (P) of one phase connected to the conversion modules (E1, E2, E3). max The difference between the sum of the power assigned to the other basic units (A, B, C, D, E, F, G, H, I) of the same conversion module (E1, E2, E3) and the sum of the power assigned to them. b) and is limited to such that it is less than or equal to the maximum threshold of the power used (S) max ).

3. The method as claimed in the preceding claim, wherein during the activation (S5) step, the basic units (A, B, C, D, E, F, G, H, I) to be activated are selected by selecting the minimum number of basic units (A, B, C, D, E, F, G, H, I) whose sum of the maximum power assigned is greater than or equal to the instantaneous power in the order of activation.

4. A power supply system (1) for a motor vehicle, comprising: a) Power supply battery, b) An on-board charger, which is connected to the battery on one hand and is intended to be connected to an external electrical power supply network capable of providing three-phase voltage, each phase of which is powered by a maximum total power consumption (P). max The on-board charger is characterized by comprising multiple conversion modules (E1, E2, E3), each of which includes multiple independent basic power conversion units (A, B, C, D, E, F, G, H, I). Each basic unit (A, B, C, D, E, F, G, H, I) is defined by a maximum power threshold (S). max Each conversion module (E1, E2, E3) is designed to be connected to one phase of an external power supply network. c) A control unit capable of implementing the method as described in any of the preceding claims.

5. A motor vehicle comprising a power supply system as described in the preceding claims.

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