Power supply system for vehicle

Abstract

The invention relates to an electric power supply system (1) for an electric or hybrid vehicle comprising an electric power supply bus (HV +, HV-) capable of powering electrical equipment installed in the vehicle, said system (1) comprising: a) a DC-DC voltage converter (50), b) at least two power supply units (10, 20, 30), each power supply unit comprising: i) a rectifier (r1, r2, r3), ii) a battery (B1, B2, B3), and iii) a switching unit (C10, C20, C30), and c) a distribution module (70) intended to be connected to a recharging module (60) external to the vehicle, the power supply system (1) being configured to operate in an operating mode in which:-the batteries (B1, B2, B3) are connected in series by a first set of switches (I3),-the distribution module (70) connecting one or more batteries (B1, B2, B3) to the external recharging module (60).

Description

Field of the Invention

[0001] The present invention relates to the field of hybrid or electric vehicles, and more particularly to an electrical power supply system for a hybrid or electric vehicle. Background Art

[0002] As is well known, an electric or hybrid vehicle includes an electric motor for propelling the vehicle and a storage battery capable of being connected to the electric motor. An inverter is connected between the battery and the electric motor and makes it possible to convert the DC voltage supplied by the battery into an AC voltage, in particular a three-phase AC voltage, in order to supply each phase of the electric motor.

[0003] The vehicle also includes an internal electrical power supply network which makes it possible to supply electrical equipment in the vehicle (such as windshield wipers, headlights, dashboard warning lights, etc.).

[0004] The voltage supplied by this network is, for example, 12 or 14 volts.

[0005] The vehicle also includes an auxiliary battery capable of supplying power to this network and a DC-DC voltage converter connected between the auxiliary battery and the battery in order to charge the auxiliary battery.

[0006] The disadvantage thereof is that a large number of converters must be installed and configured in the vehicle.

[0007] Furthermore, each battery actually consists of a set of battery cells statically connected to each other. The charge level of each battery depends on the state of charge of each battery cell. However, these battery cells may not all have the same electrical and energy characteristics. Therefore, the size of each battery must take into account the aging phenomenon and the performance of each battery, which is restrictive.

[0008] In addition, the components of the converter and the inverter are sized such that the voltages provided by the converter and the inverter are each defined within a wide voltage range. Therefore, since each of these components is not sized for the optimal operating voltage, this may on the one hand result in losses after each conversion implemented by the converter or the inverter, and on the other hand it is difficult to precisely control the output voltage of each converter and / or inverter.

[0009] Therefore, a solution is needed that can at least partially overcome the above disadvantages. Summary of the Invention

[0010] To this end, the present invention relates to an electrical power supply system for an electric or hybrid vehicle, the vehicle including an electrical power supply bus capable of supplying power to electrical equipment installed in the vehicle, the system comprising:

[0011] a) a DC-DC voltage converter,

[0012] b) At least two power supply units, each power supply unit comprising:

[0013] i) A rectifier that can provide an alternating voltage based on a direct current voltage and vice versa,

[0014] ii) A battery that is electrically connected to the rectifier, the battery being capable of operating in a discharge mode in which the battery can provide a first direct current voltage and being capable of operating in a charging mode in which the battery can be recharged based on a direct current voltage,

[0015] iii) A switch unit that includes a switch capable of connecting the battery to a converter,

[0016] c) A first set of switches that can connect the batteries of the power supply units to the batteries of adjacent power supply units so as to connect the batteries in series to form a battery group,

[0017] d) A control unit configured to control each switch of the first set of switches, the second set of switches, and each switch unit,

[0018] e) A distribution module intended to be connected to a recharge module (60) external to the vehicle, the recharge module being configured to provide power, the distribution module being configured to electrically connect at least one battery to the external recharge module so as to recharge at least one battery based on the power provided by the recharge module,

[0019] The power supply system is configured to operate in an operating mode in which:

[0020] - The batteries are connected in series through the first set of switches,

[0021] - The distribution module connects one or more batteries to the external recharge module.

[0022] The recharge module supports a fixed power supply voltage. This power supply voltage can depend on external devices connected to the recharge module and / or can be inherent to the recharge module. Thus, when the power supply voltage supported by the recharge module and available to the power supply system is sufficient to recharge the battery group connected in series simultaneously, the distribution module connects all the batteries to the recharge module. In contrast, if this power supply voltage supported by the recharge module enables only partial batteries to be recharged, the distribution module connects the recharge module to partial batteries. This makes it possible to adjust the number of batteries connected to the recharge module simultaneously according to the power supply voltage supported by the external recharge module and available for recharging the batteries of the electrical system.

[0023] Preferably, the distribution module is configured to:

[0024] a) In a first operating mode: connect the battery group connected in series to the external recharge module,

[0025] b) In the second operating mode: Half of the battery pack is connected to the external recharge module.

[0026] Thus, for example, for a battery pack connected in series and capable of being recharged based on a voltage substantially equal to 800V, if the recharge module supports a voltage of 800V, but multiple external devices are connected to the recharge module and only 400V of this voltage is available for recharging the batteries of the electrical system, the distribution module only connects half of the batteries to the external recharge module.

[0027] Thus, for another example, if the battery pack connected in series is capable of being recharged based on a voltage substantially equal to 800V, while the charging module only supports a voltage of 400V, the described power supply system enables only a part of the batteries to be connected to the recharge module, so that the recharge module does not experience voltage overload.

[0028] Thus, the power and voltage levels connected to the recharge module can be adjusted by selecting the battery pack or part of the batteries connected in series to prevent voltage and power overload of the recharge module. This also allows the batteries to be recharged even if they are not all recharged simultaneously.

[0029] In contrast, if fewer devices or no devices are connected to the charging module, and the charging module is capable of supporting a voltage sufficient to recharge the connected battery pack simultaneously, the distribution module connects all the batteries to the external recharge module.

[0030] More preferably, the distribution module includes:

[0031] a) A first switch capable of connecting the first terminal of the external recharge module to the first battery of the battery pack connected in series or to a battery located between the first battery and the last battery of the battery pack connected in series,

[0032] b) A second switch capable of connecting the second terminal of the external recharge module to a battery located between the first battery and the last battery of the battery pack connected in series or to the last battery.

[0033] Thus, this embodiment is easy to implement in the electrical system.

[0034] More preferably, each power supply unit includes a coil, which is connected to a rectifier on one hand and is intended to be connected to an AC voltage on the other hand.

[0035] Advantageously, the power supply system includes three power supply units.

[0036] The present invention also relates to a motor vehicle, which includes a power supply bus capable of supplying power to electrical devices installed in the vehicle, and a power supply system as described above.

[0037] Finally, the present invention relates to a method for controlling the above system, which is implemented by a control unit and includes the following steps:

[0038] a) Connecting battery groups in series,

[0039] b) Connecting the series-connected battery groups or partial batteries to an external recharge module. Description of the Drawings

[0040] Other features and advantages of the present invention will become more apparent by reading the following description. This description is illustrative only and should be read with reference to the drawings, in which:

[0041] Figure 1 is a circuit diagram of a power supply system according to the present invention.

[0042] Figure 2 is for showing Figure 1 a circuit diagram of a first operating mode of the power supply system.

[0043] Figure 3 is for showing Figure 1 a circuit diagram of a second operating mode of the power supply system.

[0044] Figure 4 is for showing Figure 1 a circuit diagram of a third operating mode of the power supply system. Detailed Description of the Invention

[0045] Vehicle

[0046] With reference to Figure 1 , a vehicle according to the present invention will now be described. In particular, the vehicle includes a power supply bus HV. The power supply bus HV can supply electrical energy to various electrical devices installed in the vehicle. Even more specifically, the power supply bus includes a positive terminal HV+ and a negative terminal HV-.

[0047] The vehicle further includes a power supply system 1.

[0048] Power Supply System

[0049] With reference to Figure 1 , the power supply system 1 includes at least two power supply units 10, 20, 30, a connection module 40, a DC-DC voltage converter 50, a control unit (not shown in the figure), and a distribution module 70.

[0050] Preferably, the power supply system 1 includes a first power supply unit 10, a second power supply unit 20, and a third power supply unit 30. Each power supply unit 10, 20, 30 can convert an AC voltage into a DC voltage.

[0051] Power supply units 10, 20, 30

[0052] Each power supply unit 10, 20, 30 includes: a rectifier r1, r2, r3; batteries B1, B2, B3; and a switch unit C 10 , C 20 , C 30 .

[0053] More specifically, the rectifiers r1, r2, r3 of each power supply unit 10, 20, 30 are bidirectional. In other words, each rectifier r1, r2, r3 is capable of providing an AC voltage based on a DC voltage and vice versa.

[0054] Each rectifier r1, r2, r3 includes two input terminals and two output terminals.

[0055] More specifically, in the present case, each rectifier r1, r2, r3 includes a first switch connected between a high point PH and a first midpoint PM1, a second switch connected between the first midpoint PM1 and a low point PB, a third switch connected between the high point PH and a second midpoint PM2, and a fourth switch connected between the second midpoint PM2 and the low point PB. The two input terminals of each rectifier r1, r2, r3 specify the first midpoint PM1 and the second midpoint PM2. The two output terminals specify the high point PH and the low point PB.

[0056] The batteries B1, B2, B3 of each power supply unit 10, 20, 30 are capable of operating in a discharge mode, in which the batteries B1, B2, B3 are capable of providing a first DC voltage. In addition, the batteries B1, B2, B3 of each power supply unit 10, 20, 30 are also capable of operating in a charging mode, in which the batteries B1, B2, B3 supply electrical energy.

[0057] Each battery B1, B2, B3 includes a set of storage units.

[0058] In addition, the batteries B1, B2, B3 of each power supply unit 10, 20, 30 are connected to the corresponding rectifiers r1, r2, r3. More specifically, each battery B1, B2, B3 is connected between the two output terminals of the corresponding rectifier r1, r2, r3.

[0059] The switch unit C of each power supply unit 10, 20, 30 10 , C 20 , C 30 is capable of connecting the batteries B1, B2, B3 to the DC-DC converter 50. In other words, the switch unit C 10 , C 20 , C 30Connected on the one hand to the batteries B1, B2, B3 and on the other hand to the DC-DC converter 50.

[0060] Each switching unit C 10 , C 20 , C 30 Includes a first switch I10, I20, I30 and a second switch I10', I20', I30'.

[0061] The first switches I10, I20, I30 of each power supply unit 10, 20, 30 enable the first terminals of the batteries B1, B2, B3 to be connected to the terminals of the DC-DC converter 50.

[0062] The second switches I10', I20', I30' of each power supply unit 10, 20, 30 enable the second terminals of the batteries B1, B2, B3 to be connected to the second terminals of the DC-DC converter 50.

[0063] Coil

[0064] In addition, each power supply unit 10, 20, 30 includes coils L1, L2, L3 connected to the inputs of the rectifiers r1, r2, r3; in other words, the coils are connected on the one hand to the rectifiers r1, r2, r3 and on the other hand are intended to be connected to an AC voltage.

[0065] The power supply system 1 further includes a first set of switches I3 and a second set of switches I4.

[0066] Connection module 40

[0067] The connection module 40 enables a single-phase voltage or a three-phase voltage to be connected to each power supply unit 10, 20, 30.

[0068] First group of switches I3

[0069] The first set of switches I3 is capable of connecting the batteries B1, B2, B3 of the power supply units 10, 20, 30 to the batteries B1, B2, B3 of adjacent power supply units 10, 20, 30 in order to connect the batteries B1, B2, B3 in series.

[0070] For this purpose, the first set of switches I3 includes:

[0071] a. A switch connected on the one hand to the battery B1 of the first power supply unit C10 and on the other hand to the battery B2 of the second power supply unit C20,

[0072] b. A switch connected on the one hand to the battery B2 of the second power supply unit C20 and on the other hand to the battery B3 of the third power supply unit C30.

[0073] Therefore, the batteries B1, B2, B3 can be connected in series; it is said that these batteries form a power supply branch.

[0074] Second group of switches I4

[0075] The second set of switches I4 enables the battery B1 of the first power supply unit C 10 to be connected to the power supply bus HV, in particular in order to connect the branch of the batteries B1, B2, B3 connected in series between the positive terminal HV+ and the negative terminal HV- of the power supply bus HV.

[0076] In addition, each power supply unit 10, 20, 30 may also include an EMC (electromagnetic compatibility) filter connected between each rectifier r1, r2, r3 and the connection module 40.

[0077] The control unit (not shown in the figure) is configured to control the connection module 40, the first set of switches I3, the second set of switches I4, and each switch unit C 10 、C 20 、C 30 and the opening and closing of each switch I10, I10', I20, I20', I30, I30' of each rectifier r1, r2, r3. The control unit is also capable of controlling the voltage provided and generated by each battery B1, B2, B3, for example, to regulate the current in the inductors L1, L2, L3 or to regulate the voltage to be provided to the DC-DC converter 50.

[0078] External recharge module 60

[0079] To recharge the battery, an external recharge module 60 outside the vehicle can be used, which is commonly referred to by those skilled in the art as a "DC fast charging terminal" and is denoted by the reference numeral 60 in the figure.

[0080] Therefore, the external recharge module 60 is configured to provide a power supply voltage and includes two connection terminals, such as a first terminal B 61 and a second terminal B 62 .

[0081] Distribution module 70

[0082] The distribution module 70 is intended to be connected to the external recharge module 60.

[0083] The distribution module 70 is configured to electrically connect at least one of the batteries B1, B2, B3 to the external recharge module 60 in order to recharge at least one of the batteries B1, B2, B3 using the power provided by the recharge module 60. For this purpose, the battery sets B1, B2, B3 must be connected in series through the first set of switches I3. Figures 1 to 4In the example shown, a system including three batteries B1, B2, and B3 is shown, and battery B1 represents the first battery, and battery B3 represents the "last battery".

[0084] More specifically, the distribution module 70 includes a first switch I 71 and a second switch I 72 .

[0085] The first switch I 71 is capable of connecting the first terminal B of the recharge module 60 61 :

[0086] a. To the first battery B1 of the series-connected battery group via the first point "A", and the first point "A" is located, for example, between the first battery B1 and the positive terminal HV+ of the power supply bus,

[0087] b. Or to the battery called "intermediate" via the second point "B", because this intermediate battery is connected between the first battery B1 and the last battery B3 of the series-connected battery group.

[0088] In particular, when the number of batteries is even, the second point B is located between the two batteries placed in the middle, and when the number of batteries is odd, the second point B is located on one of the storage units of the battery placed in the middle. Therefore, in the current case, the second point B is located, for example, between the first battery B1 and the second battery B2, or directly on one of the storage units of the second battery B2.

[0089] In other words, in the example shown, the first switch I 71 connects the first battery B1 or the second battery B2 to the first terminal B 61 .

[0090] The second switch I 72 is capable of connecting the second terminal B of the recharge module 60 62 :

[0091] a. To the intermediate battery via the second point B,

[0092] b. Or to the last battery B3 via the third point "C", and the third point "C" is located between the last battery and the negative terminal HV- of the power supply bus.

[0093] In other words, in the example shown, the second switch I 72 connects the second battery B2 or the third battery B3 to the second terminal B 62 .

[0094] The distribution module 70 is capable of operating in multiple operating modes.

[0095] Reference Figure 2, shows a first operating mode in which all the batteries B1, B2, B3 are connected to the recharge module 60. To this end:

[0096] - The first switch I 71 connects the first terminal B of the charging module 60 61 to the first battery B1 (via the first point A),

[0097] - The second switch I 72 connects the second terminal B of the charging module 60 62 to the last battery B3 (via the third point C).

[0098] Thus, in this case, the voltage amplitude supported by the recharge module 60 is sufficient to recharge all the batteries B1, B2, B3.

[0099] Reference Figure 3 and Figure 4 , shows two embodiments of a second operating mode of the distribution module 70 in which only some of the batteries B1, B2, B3 are connected to the recharge module 60.

[0100] According to Figure 3 the first switch I 71 connects the first terminal B of the recharge module 60 61 to one of the intermediate batteries, in other words, in this case, to the second battery B2. Further, the second switch I 72 connects the second terminal B of the recharge module 60 62 to the last battery B3.

[0101] According to Figure 4 the first switch I 71 connects the first terminal B of the recharge module 60 via the first point A 61 to the first battery B1. The second switch I 72 connects the second terminal B of the recharge module 60 via the second point B 62 to the intermediate battery, in other words, according to the example given, to the second battery B2.

[0102] In the present case, when only a part of the power voltage supported by the external recharge module 60 and available for recharging the battery set B1, B2, B3 is sufficient to charge only some of the batteries connected in series, only some of the batteries B1, B2, B3 are connected to the external recharge module 60 via the distribution module 70.

[0103] In addition, in Figure 3 and Figure 4In the operating mode shown, the (multiple) power supply units 10, 20, 30 to which the batteries B1, B2, B3 are not connected to the recharge module 60 can be electrically connected to the power supply bus via the DC-DC converter 50, in particular to supply electrical energy to the power supply bus.

Claims

1. A power supply system (1) intended to be installed in an electric or hybrid vehicle, the vehicle including a power supply bus (HV+, HV-) capable of supplying power to electrical equipment installed in the vehicle, the system (1) comprising: a) A DC-DC voltage converter (50), b) At least two power supply units (10, 20, 30), each power supply unit including: i) A rectifier (r1, r2, r3) capable of providing an alternating voltage based on a direct current voltage and vice versa, ii) A battery (B1, B2, B3) electrically connected to the rectifier (r1, r2, r3), the battery being capable of operating in a discharge mode in which the battery (B1, B2, B3) can provide a first direct current voltage, and being capable of operating in a charging mode in which the battery (B1, B2, B3) can be recharged based on a direct current voltage, iii) Switching unit (C 10 , C 20 , C 30 ), which includes switches (I10, I10', I20, I20', I30, I30') capable of connecting the batteries (B1, B2, B3) to the converter (50). c) A first set of switches (I3) capable of connecting the batteries (B1, B2, B3) of the power supply units (10, 20, 30) to the batteries (B1, B2, B3) of adjacent power supply units (10, 20, 30) so as to connect the batteries in series, d) A second set of switches (I4) capable of connecting the series-connected batteries (B1, B2, B3) to the power supply bus (HV), e) A control unit configured to control the first set of switches (I3), the second set of switches (I4), and each switch (I10, I10', I20, I20', I30, I30') of each switch unit (C 10 , C 20 , C 30 ), f) A distribution module (70) intended to be connected to a recharging module (60) external to the vehicle, the recharging module (60) being configured to provide a power supply voltage, the distribution module (70) being configured to electrically connect at least one battery (B1, B2, B3) to the external recharging module (60) so as to recharge at least one battery (B1, B2, B3) based on the voltage provided by the recharging module (60), g) A connection module (40) configured to connect a single-phase voltage or a three-phase voltage to each power supply unit (10, 20, 30), The power supply system (1) is configured to operate in an operating mode in which: - The batteries (B1, B2, B3) are connected in series by the first set of switches (I3), - The distribution module (70) connects one or more batteries (B1, B2, B3) to the external recharging module (60).

2. The power supply system (1) according to the previous claim, wherein, The distribution module (70) is configured to: a) In a first operating mode: connect the series-connected batteries (B1, B2, B3) to the external recharging module (60), b) In a second operating mode: connect half of the batteries (B1, B2, B3) to the external recharging module (60).

3. The power supply system (1) according to the preceding claim, wherein, The distribution module (70) includes: - First switch (I 71 ), which can connect the first terminal (B 61 ) of the external recharge module (60) to the first battery (B1) of the series-connected battery pack (B1, B2, B3) or a battery located between the first battery (B1) and the last battery (B3) of the series-connected battery pack (B1, B2, B3), - Second switch (I 72 ), which is capable of connecting a second terminal (B 62 ) of the external recharge module (60) to a battery located between the first battery (B1) and the last battery (B3) of a series-connected battery group (B1, B2, B3) or to the last battery (B3).

4. The power supply system (1) according to any one of the preceding claims, wherein, Each power supply unit (10, 20, 30) includes a coil (L1, L2, L3), the coil being connected on the one hand to the rectifier (r1, r2, r3) and on the other hand intended to be connected to an alternating voltage.

5. The power supply system (1) according to any one of the preceding claims, including three power supply units (10, 20, 30).

6. A motor vehicle, which comprises a power supply bus (HV+, HV-) capable of supplying power to electrical equipment installed in the vehicle and a power supply system (1) according to any one of the preceding claims.

7. A method for controlling a system (1) according to any one of the preceding claims, the method being implemented by the control unit and comprising the following steps: a) Connecting battery groups (B1, B2, B3) in series, b) Connecting the series-connected battery groups or partial batteries (B1, B2, B3) to an external recharge module (60).

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