Charging system, voltage converter unit, and accumulator unit

Abstract

The invention relates to a charging system (2) for an accumulator (48) in an electric vehicle, comprising: a voltage converter unit (3) and an accumulator unit (4), wherein: the accumulator unit (4) is designed to be supplied with electrical energy via two supply terminals (44, 45); an accumulator (48) of the accumulator unit (4) has two terminals (481, 482) which are detachably connected to the supply terminals (44, 45) via a second and a third isolating switch (46, 47); the voltage converter unit (3) is designed as a structural unit which is separate from the accumulator unit (4) and is connected to the accumulator unit (4) via three terminals (31, 32, 33); and, in the connected state, within the accumulator unit (4) • two of the three terminals (33, 32) are connected to the two terminals (481, 482) of the accumulator (48) and • the third of the three terminals (31) is connected to one of the supply terminals (44, 45), and within the voltage converter unit (3) the third of the three terminals (31) leads via a first isolating switch (36). The voltage converter unit (3) comprises a first voltage converter (37) and a second voltage converter (57).

Description

[0001] CHARGING SYSTEM, VOLTAGE CONVERTER UNIT, AND

[0002] STORAGE UNIT

[0003] The invention relates to the field of charging systems for electrical energy storage devices, in particular mobile electrical energy storage devices, in particular for electric vehicles.

[0004] Known chargers, especially for electric vehicles, are typically connected between a charging station and an electrical energy storage device. They serve to adapt the voltage present at the charging station to the voltage level of the energy storage device, as needed. This depends on the voltage at the charging station: either the voltage present at an input of the charger can be passed through to the energy storage device (bypass mode) without the need for voltage conversion, or it must be converted by a converter to the voltage level of the energy storage device. Such chargers may be subject to regulations requiring that the energy storage device be fully disconnectable from the charging station using a mechanical isolating switch.

[0005] Conventional chargers incorporate a voltage converter unit connected between the charging station and the energy storage device—typically a rechargeable battery. In bypass mode, rapid charging processes can occur that involve relatively high currents, so the conductor cross-sections in the voltage converter unit must be designed accordingly. Furthermore, multiple disconnectors must be present in the voltage converter unit to ensure full-pole disconnection. Furthermore, a modular design, with or without a voltage converter unit, can result in unnecessary duplication of components.

[0006] It is therefore an object of the invention to provide a charging system, a voltage converter unit, and a storage unit of the type mentioned above, which eliminates the above-mentioned disadvantages and can be connected to various charging stations for a charging process.

[0007] At least one of these objects is achieved by a charging system, a voltage converter unit, and a storage unit having the features of the corresponding independent patent claims.

[0008] This makes it possible to disconnect both the storage unit and a voltage converter arranged in the voltage conversion unit from the storage supply connections using the three isolating switches.

[0009] Furthermore, it is possible to equip the voltage converter unit with only a single isolating switch or no isolating switch at all, since additional isolating switches are present in the storage unit and - because the voltage converter unit is not connected directly to the charging station, but via the storage unit - the voltage converter unit can be disconnected from the charging station via the isolating switches in the storage unit.

[0010] Furthermore, it is possible to connect the storage unit directly to the first charging station via the two storage supply connections, without routing the required conductors through the voltage converter unit. This, in turn, eliminates the need to route high currents, such as those encountered during rapid charging in bypass mode, through the voltage converter unit, and allows the conductors in voltage converter unit 3 to be designed accordingly smaller.

[0011] Furthermore, it is possible to design and operate the storage unit entirely without the voltage converter unit. The two storage supply connections of the storage unit can be adopted and operated unchanged, as can supply lines for connection to a first charging station. Thus, based on the same storage unit, a configuration can be realized with or without the voltage converter unit. This is advantageous during production, as the storage unit can be used unchanged for both configurations. Furthermore, a storage unit, or a vehicle containing it, can be retrofitted with a voltage converter unit even after commissioning. The voltage converter unit can be present as a module or not. Such a module has only a single circuit breaker or no circuit breaker at all. The total number of circuit breakers is thereby minimized.

[0012] The charging system has a first voltage converter and a second voltage converter. This allows for a choice between the two voltage converters depending on the type of charging station available for a charging process.

[0013] In embodiments, the charging system is designed according to at least one of claims 2, 3, 4, 5, 6, 7.

[0014] In embodiments, the charging system is designed according to claim 8. This makes it possible to manufacture the charging system in the form of separate modules, i.e., voltage converter unit and storage unit, and to combine them for use. In particular, the modularized charging system can be operated either with or without a voltage converter unit. In embodiments, the charging system is designed according to claim 9. This makes it possible to easily establish and disconnect the connection between the voltage converter unit and the storage unit.

[0015] In embodiments, the charging system is designed according to claim 10. This makes it possible to operate the charging system with a safety system commonly used in electric vehicle technology, for example an interlock or HV interlock or with pilot contacts.

[0016] In embodiments, the charging system is designed according to claim 11 and / or claim 12. This makes the charging system suitable for use in an electric vehicle. The corresponding voltages of the charging station can be, for example, 400 volts or 800 volts.

[0017] The voltage converter unit is designed according to claim 13. Thus, the first input terminal can be disconnected from a first voltage converter of the voltage converter unit using the first isolating switch.

[0018] The storage unit is designed according to claim 14. Thus, the storage unit can be operated either with or without a voltage converter unit.

[0019] The subject matter of the invention is explained in more detail below using preferred embodiments, which are illustrated in the accompanying drawings. They show schematically:

[0020] Figure 1 shows a charging system with a voltage converter unit and a storage unit according to a first embodiment with only a first voltage converter in the voltage converter unit. Figure 2 shows the charging system with a specific first embodiment of the voltage converter unit from Figure 1.

[0021] Figure 3 shows a charging system with a voltage converter unit and a storage unit according to a second embodiment with only a first voltage converter in the voltage converter unit.

[0022] Figure 4 shows the charging system with a concrete second embodiment of the voltage converter unit of Fig. 3.

[0023] Figure 5 shows a charging system according to the invention corresponding to the charging system of Figure 1, but with two voltage converters in the voltage converter unit,

[0024] Figure 6 shows the charging system with a concrete first embodiment of the voltage converter unit of Figure 5.

[0025] Figure 7 shows a charging system according to the invention corresponding to the charging system of Figure 3, but with two voltage converters in the voltage converter unit.

[0026] Figure 8 shows the charging system with a concrete second embodiment of the voltage converter unit of Figure 7.

[0027] In principle, identical parts or parts with the same effect are or should be provided with the same reference symbols in the figures.

[0028] Figure 1 shows a charging system 2 connected to a first charging station 1A. The charging system 2 has a voltage converter unit 3 and a storage unit 4.

[0029] The voltage converter unit 3 has a first input terminal 31, an output terminal 32, a common terminal 33, and a first voltage converter 37 for converting a first input voltage applied between the first input terminal 31 and the common terminal 33 into a first output voltage applied between the output terminal 32 and the common terminal 33. During operation of the voltage converter 37, its first input voltage is equal to an output voltage of the first charging station 1A, and its first output voltage is equal to a voltage of the storage device 48.

[0030] The storage unit 4 has: a first connection 41 for connection to the first input connection 31 of the voltage converter unit 3, a second connection 42 for connection to the output connection 32 of the voltage converter unit 3 and for feeding a first connection 481 of the storage 48, a third connection 43 for connection to the common connection 33 of the voltage converter unit 3 and for feeding a second connection 482 of the storage 48, a first storage supply connection 44 for connection to a first charging connection 11A of the first charging station 1A, and a second storage supply connection 45 for connection to a second charging connection 12A of the first charging station 1A.

[0031] The connection of the first or second storage supply connection 44, 45 to a first charging connection 11A or a second charging connection 12A of the first charging station 1 is effected via a first supply line 13 or a second supply line 14,

[0032] In some embodiments, the two supply lines 13, 14 are designed as separate cables, and the two storage supply connections 44, 45 are formed on separate connectors. This ensures that the individual, separate cables do not become too heavy if they must be designed for high charging currents. In some embodiments, the two supply lines 13, 14 are designed as a single cable, and the two storage supply connections 44, 45 are formed on a single connector.

[0033] Within the voltage converter unit 3

[0034] • the first input terminal 31 of the voltage converter unit 3 can be separated from the first voltage converter 37 via a first isolating switch 36.

[0035] Within storage unit 4

[0036] • the first storage supply connection 44 is connected to the first connection 41 of the storage unit 4,

[0037] • the second connection 42 of the storage unit 4 and the first connection

[0038] 481 of the memory 48 is detachably connected to the first memory supply connection 44 via a second isolating switch 46, and

[0039] • the third connection 43 of the storage unit 4 and the second connection

[0040] 482 of the memory 48 is detachably connected to the second memory supply connection 45 via a third isolating switch 47.

[0041] In some embodiments, the second storage supply terminal 45 is connected to the first terminal 41 of the storage unit 4 instead of the first. This corresponds, with the same polarity of the storage unit 48 and the first charging station 1A, to an operating mode of the voltage converter 37 with reversed polarity.

[0042] The storage unit 4, and in particular the storage unit 48, can be equipped with a battery management system (not shown) and / or a charging controller of a known type. The latter can, for example, control the first charging station 1A and / or the voltage converter unit 3 via communication connections (not shown). In embodiments, the storage unit 4 is part of a consumer circuit, in the case of a vehicle also called a traction circuit, or is connected to a consumer circuit. Furthermore, the storage unit 4 can have additional disconnect switches 483, 484 for disconnecting the first and second terminals 481, 482 of the storage unit 48 from the remaining elements, for example, from the voltage converter unit 3 and the consumer circuit. The presence of such additional disconnect switches 483, 484 for disconnecting the storage unit 4 can be prescribed by standards.

[0043] The circuit breakers 36, 46, 47 and the voltage converter 37 are controlled by a controller 100 and communication links (not shown). The controller 100 is shown in the voltage converter unit 3 as an example, but can also be located in the storage unit 4 or outside both units. Other common elements for ensuring functionality and safety, for example, for monitoring the storage supply connections 44, 45, are not shown.

[0044] If the voltage supplied by the first charging station 1A is not equal to the voltage required to charge the storage device 48, the charging system 2 can be switched to a converter mode. In this mode, the second isolating switch 46 is open, and the first isolating switch 36 and third isolating switch 47 are closed. The voltage converter 37 is pulsed.

[0045] In doing so, it converts the voltage of the first charging connection 11 A present at the first input connection 31 of the voltage converter unit 3 via the first connection 41 and the first storage supply connection 44 of the storage unit 4 and the first supply line 13 into the voltage present at the output connection 32 of the voltage converter unit

[0046] 3 voltage applied. This is applied via the second terminal 42 of the storage unit

[0047] 4 at the first terminal 481 of the storage unit 48. The voltages mentioned are referenced to the common terminal 33. The voltage of the second charging terminal 12A is applied via the second supply line 14 and the second storage supply terminal 45 to the third terminal 43 of the storage unit 4 and thus to the common terminal 33 of the voltage converter unit 3 and to the second terminal 482 of the storage unit 48.

[0048] If the voltage supplied by the first charging station 1A is equal to the voltage required to charge the storage unit 48, the charging system 2 can be switched to bypass mode. In this mode, the first isolating switch 36 is open, and the second isolating switch 46 and third isolating switch 47 are closed. The first voltage converter 37 is not pulsed. The voltage from the first charging station 1A is applied to the storage unit 48.

[0049] If the charging system 2 is to be galvanically separated from the charging station 1, all three isolating switches 36, 46, 47 are opened.

[0050] The storage device 48 is typically a rechargeable battery.

[0051] The first voltage converter 37 is typically a DC-DC converter. It can be, for example, a charge pump, a boost converter, a buck converter, or a combination of both, or it can have a different topology, such as a bridge circuit that implements a DC-DC converter. A charge pump can be designed to double or multiply the voltage.

[0052] During operation, the first voltage converter 37 typically transfers electrical energy from the first charging station 1 A, which feeds the first voltage converter 37 via the first input terminal 31 and the common terminal 33, to the storage device 48, which is fed by the first voltage converter 37 via the output terminal 32 and the common terminal 33. In embodiments, a feedback mode can also be implemented, in which energy is transferred in the opposite direction. For this purpose, passive valves (diodes) in the first voltage converter 37 can be replaced by active semiconductor switches.

[0053] Figure 2 shows a charging system 2 in which the first voltage converter 37 is designed as a charge pump. In the variant of a charge pump shown here, an inductance LRES is connected in series with a storage capacitor CRES, forming a resonant circuit. The operation of this first voltage converter 37 is explained in WO 2018 / 046370 A1, the content of which is hereby incorporated by reference in its entirety. Figure 2 also shows the additional disconnect switches 483, 484 for disconnecting the storage device 48. These can also be present in the more general representation according to Figure 1.

[0054] Figures 3 and 4, analogous to Figures 1 and 2, each show a charging system 2 in which the first isolating switch 36 is not arranged in the voltage converter unit 3, but as the first isolating switch 36b in the storage unit 4. The first storage supply connection 44 or the second storage supply connection 45 of the storage unit 4 is detachably connected to the first connection 41 of the storage unit 4 via the first isolating switch 36b of the storage unit 4. In the embodiments of Figures 3 and 4, there is therefore no isolating switch in the voltage converter unit 3, in particular no isolating switch for disconnecting the third of the three connections 31 of the voltage converter unit 3.

[0055] Figure 5 shows a charging system 2, connectable or connected to a first charging station 1A and / or to a second charging station 1B. The charging system 2 has a voltage converter unit 3 and a storage unit 4.

[0056] The voltage converter unit 3 has a first input terminal 31, an output terminal 32, a common terminal 33, and a first voltage converter 37 for converting a first input voltage applied between the first input terminal 31 and the common terminal 33 into a first output voltage applied between the output terminal 32 and the common terminal 33.

[0057] Within the voltage converter unit 3

[0058] • the first input terminal 31 of the voltage converter unit 3 can be separated from the first voltage converter 37 via a first isolating switch 36.

[0059] The voltage converter unit 3 additionally has a second input terminal 51, a third input terminal 52, and a second voltage converter 57 for converting a second input voltage applied between the second input terminal 51 and the third input terminal 52 into a second output voltage applied between the output terminal 32 and the common terminal 33.

[0060] The voltage converter unit 3 also has: a first converter supply connection 54 for connection to a first charging connection 11B of a second charging station 1B, and a second converter supply connection 55 for connection to a second charging connection 12B of the second charging station 1B.

[0061] The second voltage converter 57 is typically an AC-DC converter. It can be a mobile electrical converter, in particular an electrical converter integrated into an electric vehicle. It is typically used for charging from the electrical grid with two-phase alternating current or three-phase alternating current.

[0062] Figure 6 shows the charging system 2 from Figure 5, whose voltage converter unit comprises the first voltage converter 37 and the second voltage converter 57. The first voltage converter 37 is designed as a charge pump, as in Figure 2. In the variant of a charge pump shown here, an inductance LRES is connected in series with a storage capacitor CRES, forming a resonant oscillating circuit. The operation of this first voltage converter 37 is explained in WO 2018 / 046370 A1, the content of which is hereby incorporated by reference in its entirety. The charging system 2 shown in Figures 5 and 6 also contains the additional isolating switches 483, 484 for disconnecting the storage device 48 (not shown in Figures 5 and 6), as shown in Figure 2.

[0063] Figures 7 and 8, analogous to Figures 5 and 6, each show a charging system 2 in which the first isolating switch 36 is not arranged in the voltage converter unit 3, but as the first isolating switch 36b in the storage unit 4. The first storage supply connection 44 or the second storage supply connection 45 of the storage unit 4 is detachably connected to the first connection 41 of the storage unit 4 via the first isolating switch 36b of the storage unit 4. In the embodiments of Figures 7 and 8, there is therefore no isolating switch in the voltage converter unit 3, in particular no isolating switch for disconnecting the third of the three connections 31 of the voltage converter unit 3.

Claims

PATENT CLAIMS Charging system (2), in particular for a mobile storage device (48), in particular for a storage device (48) in an electric vehicle, comprising a voltage converter unit (3) and a storage unit (4), wherein the storage unit (4) is configured for supplying electrical energy via two storage supply connections (44, 45), a storage device (48) of the storage unit (4) has two connections (481, 482) which are disconnectably connected to the storage supply connections (44, 45) via a second and a third disconnect switch (46, 47), the voltage converter unit (3) is configured as a separate component from the storage unit (4), which is connected to the storage unit (4) via three connections (31, 32, 33) of the voltage converter unit (3), and in the connected state within the storage unit (4) • two of the three terminals (32, 33) of the voltage converter unit (3) are connected to the two terminals (481, 482) of the storage unit (48), and either according to a second embodiment within the storage unit (4) • the third of the three terminals (31) of the voltage converter unit (3) is connected via a first disconnect switch (36b) to one of the storage supply terminals (44, 45), or according to a first embodiment variant within the storage unit (4) • the third of the three terminals (31) of the voltage converter unit (3) is connected to one of the storage supply terminals (44, 45), and within the voltage converter unit (3) the third of the three terminals (31) of the voltage converter unit (3) leads via a first disconnect switch (36), characterized in that the voltage converter unit (3) comprises a first voltage converter (37) and a second voltage converter (57). Charging system (2) according to claim 1, characterized in that the first voltage converter (37) is a DC-DC converter which can be connected to a DC charging station (1A), charging system (2) according to claim 1 or 2, characterized in that the second voltage converter (57) is an AC-DC converter which can be connected to an AC charging station (1B).Charging system (2) according to one of the preceding claims, wherein the voltage converter unit (3) has a first input terminal (31), an output terminal (32), a common terminal (33), and the first voltage converter (37) for converting a first input voltage applied between the first input terminal (31) and the common terminal (33) into a first output voltage applied between the output terminal (32) and the common terminal (33), wherein the storage unit (4) has a first terminal (41) for connection to the first input terminal (31) of the voltage converter unit (3), a second terminal (42) for connection to the first output terminal (32) of the voltage converter unit (3) and for supplying a first terminal (481) of the storage (48), a third terminal (43) for connection to the common terminal (33) of the voltage converter unit (3) and for supplying a second terminal (482) of the storage (48). The charging system (2) has a first storage supply connection (44) for connection to a first charging port (11A) of a first charging station (1A), and a second storage supply connection (45) for connection to a second charging port (12A) of the first charging station (1A). Charging system (2) according to claim 4, wherein either according to the second embodiment within the storage unit (4) • the first storage supply connection (44) is disconnectable via the first disconnect switch (36b) and connected to the first connection (41) of the storage unit (4), • the second terminal (42) of the storage unit (4) and the first terminal (481) of the storage unit (48) via the second disconnect switch (46) are detachably connected to the first storage supply connection (44), and • the third terminal (43) of the storage unit (4) and the second terminal (482) of the storage unit (48) via the third disconnect switch (47) are detachably connected to the second storage supply connection (45). or according to the first embodiment variant within the voltage converter unit (3) • the first input terminal (31) of the voltage converter unit (3) can be disconnected from the voltage converter (37) via a first disconnect switch (36) within the storage unit (4) • the first storage unit supply connection (44) is connected to the first connection (41) of the storage unit (4), • the second terminal (42) of the storage unit (4) and the first terminal (481) of the storage unit (48) via the second disconnect switch (46) are detachably connected to the first storage supply connection (44), and • the third terminal (43) of the storage unit (4) and the second terminal (482) of the storage unit (48) via the third disconnect switch (47) are detachably connected to the second storage supply connection (45). Charging system (2) according to one of the preceding claims, wherein the voltage converter unit (3) has a second input connection (51), a third input connection (52), and a second voltage converter (57) for converting a second input voltage applied between the second input connection (51) and the third input connection (52) into a second output voltage applied between the output connection (32) and the common connection (33), wherein the storage unit (4) has a first connection (41) for connection to the input connection (31) of the voltage converter unit (3), a second connection (42) for connection to the output connection (32) of the voltage converter unit (3) and for supplying a first connection (481) of the storage (48),a third connection (43) for connection to the common connection (33) of the voltage converter unit (3) and for supplying a second connection (482) of the storage unit (48), a first storage supply connection (44) for connection to a first charging connection (11A) of a first charging station (1A), and a second storage supply connection (45) for connection to a second charging connection (12A) of the first charging station (1A), exhibits, wherein either according to the second embodiment variant within the storage unit (4) • the first storage supply connection (44) is disconnectable via the first disconnect switch (36b) and connected to the first connection (41) of the storage unit (4), • the second terminal (42) of the storage unit (4) and the first terminal (481) of the storage unit (48) via the second disconnect switch (46) are detachably connected to the first storage supply connection (44), and • the third terminal (43) of the storage unit (4) and the second terminal (482) of the storage unit (48) via the third disconnect switch (47) are detachably connected to the second storage supply connection (45). or according to the first embodiment variant within the voltage converter unit (3) • the first input terminal (31) of the voltage converter unit (3) can be disconnected from the voltage converter (37) via a first disconnect switch (36) within the storage unit (4) • the first storage supply connection (44) is connected to the first connection (41) of the storage unit (4), • the second terminal (42) of the storage unit (4) and the first terminal (481) of the storage unit (48) are connected to the first storage supply terminal (44) via the second disconnect switch (46) and are disconnectable. • the third terminal (43) of the storage unit (4) and the second terminal (482) of the storage unit (48) via the third disconnect switch (47) are detachably connected to the second storage supply connection (45). Charging system (2) according to one of the preceding claims, wherein the voltage converter unit (3) has a first converter supply connection (54) for connection to a first charging connection (11B) of a second charging station (1B), and a second converter supply connection (55) for connection to a second charging connection (12B) of the second charging station (1B). Charging system (2) according to one of the preceding claims, wherein the voltage converter unit (3) is designed to be manufacturable, handleable, and transportable independently of the storage unit (4). Charging system (2) according to one of the preceding claims, wherein the three connections (31, 32, 33) via which the voltage converter unit (3) is connected to the storage unit (4) are detachable and reconnectable connections, in particular plug-in connections, screw connections, or clamp connections.Charging system (2) according to one of the preceding claims, wherein the storage supply connections (44, 45) are configured on a single connector or on two separate connectors, wherein in particular this single connector or these two connectors each have safety contacts for a pilot circuit and a safety circuit, respectively. Charging system (2) according to one of the preceding claims, wherein the storage supply connections (44, 45) are configured for a maximum fast charging rate. The charging current is designed to be more than twice the maximum charging current that can be supplied by the voltage converter unit (3).

12. Charging system (2) according to one of the preceding claims, wherein the storage supply connections (44, 45) are designed for a maximum fast charging current of over 300, in particular over 400 amperes, and / or the voltage converter unit (3) is designed for a maximum charging current of over 50 amperes, in particular over 100 amperes.

13. Voltage converter unit (3), in particular for use in a charging system (2) according to one of claims 1 to 12, comprising a first input terminal (31) for connection to a first pole of an input voltage source, an output terminal (32) for connection to a first pole of a load to be supplied, and a common terminal (33) for connection to a second pole of the input voltage source and a second pole of the load, wherein the first input terminal (31) leads via a first disconnect switch (36).

14. Storage unit (4), in particular for use in a charging system (2) according to any one of claims 1 to 12, comprising two storage supply connections (44, 45) and a storage unit (48), wherein the storage unit (48) has two connections (481, 482) which are disconnectably connected to the storage supply connections (44, 45) via a second and a third disconnect switch (46, 47), wherein the storage unit (4) has three connections (41, 42, 43) for connection to corresponding connections of a voltage converter unit (3), and within the storage unit (4) • two of the three terminals (42, 43) are connected to the two terminals (481, 482) of the memory (48), and either according to a second design variant • the third of the three terminals (41) is disconnectable via a first disconnect switch (36b) and connected to one of the storage supply terminals (44, 45), or according to a first embodiment variant • the third of the three terminals (41) is connected to one of the storage supply terminals (44, 45).

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