Connecting device for a device for charging an electrical energy storage device, charging device and electric vehicle

Abstract

The invention relates to a connection for a charging circuit for charging an electrical energy storage device by means of a single-phase or multi-phase AC voltage. For this purpose, it is provided that a filter device is provided for suppressing interference signals at the input before switching between single-phase or multi-phase charging processes. In this way, when switching between single-phase or multi-phase charging, the properties of the filter device, in particular the capacitive properties, are not affected by the circuit configuration.

Description

Technical Field

[0001] The invention relates to a connecting device for a device for charging an electrical energy storage device. The invention also relates to a charging device for charging an electrical energy storage device and an electric vehicle having such a device. Background Art

[0002] A vehicle that is driven completely or at least partially electrically obtains its driving energy from an electrical energy storage device, such as a traction battery, for example. Such a traction battery can be charged with the aid of electrical energy from an energy supply grid and then provides electrical energy for driving the vehicle. In particular, during longer parking times of the vehicle, the traction battery can be charged with the aid of electrical energy from a single-phase or multi-phase AC voltage connection, such as is usually available in almost every household appliance.

[0003] Publication DE 102010010722A1 discloses, for example, a charger for electric vehicles. The publication describes a circuit for connecting a charging unit for a battery to a power supply network, wherein the power supply network has a plurality of connections. The charging unit has at least two stages, wherein each stage can be connected to all connections of the power supply network. Summary of the invention

[0004] The invention discloses a connecting device for a device for charging an electrical energy storage device, a charging device for charging an electrical energy storage device, and an electric vehicle having the features of the independent claims. Further advantageous embodiments are the subject matter of the dependent claims.

[0005] This provides:

[0006] A connection device for a device for charging an electric energy storage device, the connection device having an input connection, an output connection, a switching device and a filtering device. The input connection includes a plurality of phase connections. The input connection is designed to be optionally connected to either a single-phase or a multi-phase electric energy source. The output connection includes a plurality of phase connections. Here, the output connection is designed to be connected to a device for charging an electric energy storage device. The switching device is designed to optionally electrically connect either one or more electrical phases of the input connection to corresponding phase connections of the output connection. The filtering device is designed to filter out electrical interference signals on the electrical connection between the input connection and the output connection. The filtering device is electrically arranged between the input connection and the switching device. In particular, the switching device is arranged between the filtering device and the output connection.

[0007] Also provided:

[0008] A charging device for charging an electrical energy storage device comprises a connecting device according to the present invention and a device for charging the electrical energy storage device. The device for charging the electrical energy storage device is designed to charge the electrical energy storage device using a single-phase or multi-phase AC voltage provided at an input connection of the connecting device.

[0009] Finally provided:

[0010] An electric vehicle comprises an electric drive system, an electric energy storage device and a charging device according to the invention for charging the electric energy storage device.

[0011] The invention is based on the recognition that electrical energy can be used from a single-phase or multi-phase energy supply network for charging an electrical energy storage device, in particular for charging a traction battery of an electric vehicle. For this purpose, the charging device is usually designed for the maximum available number of electrical phases of the AC voltage network. Therefore, the charging device is usually designed for three-phase operation. However, if only a few phases, for example only one electrical phase, are available for charging the electrical energy storage device, then a corresponding switch must be performed in the charging device.

[0012] Furthermore, in charging devices for charging electrical energy storage devices with the aid of electrical energy from an energy supply network, precautions must also be taken in order to prevent interference, in particular high-frequency interference signals, from being fed into the energy supply network or at least to minimize them to a permissible extent. For this purpose, a combination of capacitive and inductive components is usually provided. In conventional charging devices, such filter elements are usually arranged between a switching device for selecting the electrical phase to be used on the one hand and the charging electronics on the other hand. Depending on the selection of the electrical phase to be used for the charging process and the switch position corresponding thereto, different characteristics are thus produced in the filter device for minimizing electrical interference signals.

[0013] The idea of ​​the present invention is therefore to take this knowledge into account and to provide a connecting device for a charging device for charging an electrical energy storage device, which can achieve the same or at least almost the same filter characteristics for suppressing interference signals as independently as possible of the number of electrical phases to be used for the charging process.

[0014] To this end, the invention provides that the filter device for suppressing electrical interference signals during the charging process is arranged in an electrical path between an input connector and a switching device for selecting the electrical phase to be used. In other words, the filter device is directly arranged on the input connector of the charging device. As a result, the same electrical characteristics of the filter device are always present on the input connector regardless of the switch position of the switching element in the switching device. In this way, the individual components of the filter device can be optimized for this always constant configuration. As a result, on the one hand, improved filter characteristics are produced with respect to the suppression of interference signals, and on the other hand, the size of the components can be minimized by this optimization. This not only leads to reduced costs, but also leads to savings in weight and structural volume.

[0015] According to one embodiment, the filter device comprises at least one first Y-type capacitor assembly. In this first Y-type capacitor assembly, the capacitor elements are each arranged between an electrical phase and a reference potential. In addition, so-called X-type capacitors can also be provided, which are each arranged between two phases. Since the filter device with the Y-type capacitors is arranged directly on the input connection, the properties of this capacitor assembly are maintained independently of the switch position of the switch in the downstream switch device.

[0016] According to one embodiment, the filter device comprises a series circuit consisting of a first Y-type capacitor assembly, a first inductive filter element and a second Y-type capacitor assembly. The second Y-type capacitor assembly can be designed identically or at least almost identically to the first Y-type capacitor assembly. In this way, a symmetrical circuit structure is produced. Of course, in addition to the second Y-type capacitor assembly, further X-type capacitors can also be provided.

[0017] According to one embodiment, the filter device comprises a series circuit consisting of a first Y-type capacitor assembly, a first inductive filter element, a second Y-type capacitor assembly, a second inductive filter element and a third Y-type capacitor assembly. In addition, a filter assembly with even more inductive filter elements and capacitor assemblies connected in series is also feasible in principle. By using a plurality of inductive and capacitive filter components connected in series, the filter characteristics can be further improved.

[0018] According to one embodiment, the connection device comprises a voltage detector. The voltage detector can be designed to detect the voltage at the phase connection of the input connection. In this case, the switching device can be designed to electrically connect the corresponding phase connection of the input connection to the corresponding phase connection of the output connection when the voltage at the corresponding phase connection of the input connection exceeds a predetermined target value. In this way, for example, switching can be automatically performed in the switching device depending on the single-phase or multi-phase voltage available at the input connection.

[0019] The above-mentioned designs and improvements can be combined with each other arbitrarily as long as it makes sense. Other designs, improvements and implementations of the present invention also include combinations of features described above or below with respect to the embodiments of the present invention that are not explicitly mentioned. In particular, those skilled in the art will also add individual aspects as improvements or supplements to the corresponding basic forms of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Further features and advantages of the present invention are explained below with the aid of the accompanying drawings.

[0021] Figure 1 A schematic diagram showing a block diagram of a charging device according to an embodiment;

[0022] Figure 2 A schematic diagram showing a block diagram of a charging device according to another embodiment;

[0023] Figure 3 A schematic diagram showing a block diagram of a charging device according to another embodiment;

[0024] Figure 4 A schematic diagram showing a basic circuit diagram of a charging device with a connecting device according to one embodiment is shown;

[0025] Figure 5 A schematic diagram of a basic circuit diagram of a charging device according to another specific embodiment is shown. DETAILED DESCRIPTION

[0026] Figure 1A schematic diagram of a block diagram of a charging device for charging an electrical energy storage device 5 according to one embodiment is shown. The charging device can be fed by a single-phase or multi-phase AC voltage source 3. For example, this can involve a single-phase or multi-phase connection connected to an electrical energy supply network, such as a low-voltage network. The single-phase or multi-phase electrical energy source 3 is first connected to a filter device 1. This filter device 1 can, for example, eliminate interference signals, in particular high-frequency interference signals, or at least reduce them to a predetermined scale. Such interference signals may be caused, for example, by a charging circuit 4, which converts the single-phase or multi-phase AC voltage provided by the AC voltage source 3 into a DC voltage in order to charge the electrical energy storage device 5.

[0027] The charging device further comprises a switching device 2 which is capable of coupling one or more electrical phases of an AC voltage source 3 to a charging circuit 4. If, for example, only a single-phase AC voltage is provided by the AC voltage source 3, the switching device 2 can then couple only this phase of the voltage to the charging circuit 4. If necessary, in this case, the phase L1, L2 or L3 of the voltage can be provided at a plurality of phase connections of a multi-phase charging circuit. If the charging circuit comprises a plurality of single-phase charging circuits, as will be explained below, the phase of the voltage can also be provided at a plurality of single-phase charging circuits in the case of a single-phase voltage supply.

[0028] If an AC voltage, for example a three-phase AC voltage, is provided by AC voltage source 3 at two or more phases, then switching device 2 can couple all voltage-carrying phases to corresponding connections of charging circuit 4 .

[0029] For conventional charging devices, the filter device is usually electrically arranged between the switch device 2 and the charging circuit 4 , while a special feature of this embodiment is that the filter device 1 is arranged between the AC voltage source 3 and the switch device 2 .

[0030] Figure 2 1 shows a schematic block diagram of a charging device according to another embodiment. Figure 2 The charging device of the embodiment of corresponds largely to the previously described embodiment and differs in particular in that a separate charging circuit 4 - i is provided for each electrical phase.

[0031] Figure 3 1 shows a schematic block diagram of a charging device according to another embodiment. Figure 3The charging device of the embodiment of the embodiment corresponds to the embodiment described above to a large extent and differs in particular in that a separate filter device 2-i is provided for each electrical phase. In this case, a filter component can be provided for each electrical phase in each filter device of the individual filter devices 2-i.

[0032] Figure 4 A schematic diagram of a principle circuit diagram of a charging device for charging an electrical energy storage device 5 according to one embodiment is shown. The maximum number of three electrical phases L1, L2 and L3 shown here is only used for a better understanding and does not represent a limitation of the invention here or in the other embodiments. In addition to the components shown here, the charging device can also include other components, such as, for example, disconnect switches or overcurrent / overvoltage protection elements, if necessary. These components are not shown in the principle circuit diagram shown here for a better understanding.

[0033] Analogously to the previously described embodiments, a single-phase or multi-phase AC voltage can be provided by an AC voltage source 3. This AC voltage can be provided at an input connection 11. In addition to the phases L1, L2 and L3 of the voltage-carrying circuit, a neutral conductor N and a protective conductor PE can also be connected to the input connection 11. A filter device 1 is provided between the input connection 11 and the switching device 2 already described above. This filter device 1 can, for example, eliminate or minimize interference signals, in particular high-frequency interference signals, caused, for example, by the charging circuit 4.

[0034] exist Figure 4 In the embodiment shown, the individual electrical phases L1, L2 and L3 can be coupled to the corresponding connection 12 for connecting the charging circuit by means of the switching elements in the switching device 2. As an alternative, in the case where the charging voltage is only provided at one phase, for example L1, the single-phase charging voltage can be provided at all phase connections of the charging circuit by means of the corresponding switch positions in the switching device 2. Figure 4 In the schematic diagram of , for example, the voltage of the first phase L1 can also be provided at the output connection 12 in addition to the phase connections for L2 and L3 .

[0035] Furthermore, the switching device 4 can also include further switching elements in order to provide an input voltage on a further phase L2 or L3 also on the output side at a plurality of phase connections. For example, a single-phase voltage can be provided on phase L3 and also on L1 and / or L2, or a voltage can be provided on L2 and additionally on L1 and / or L3.

[0036] The filter device 1 can, for example, include a series circuit consisting of a first capacitor element C1, a first inductive structural element I1 and a second capacitor element C2. The first capacitor element and / or the second capacitor element C1, C2 can each include a so-called Y-type capacitor and an X-type capacitor. The Y-type capacitor Cy is, for example, arranged between the phases L1, L2, L3 and the reference potential PE. The X-type capacitor Cx can, for example, be arranged between two electrical phases L1, L2, L3. The inductive structural element I1 can, for example, have a suitable inductance in each phase. If a neutral line N is also optionally provided in the charging device, an inductance can also be provided in this neutral line N if necessary.

[0037] If the filter device 1 comprises a plurality of capacitor elements C1 , C2 , all of these capacitor elements can be made identically or at least of the same type.

[0038] The switching device 2 is arranged between the filter device 1 and the output connection 12, which can couple the correspondingly activated phase to the charging circuit 4. For this purpose, for example, an electrical or mechanical switching element S1, S2, S3 can be provided for each electrical phase. As an alternative, it is also possible that at least one electrical phase L1 is permanently connected to the corresponding phase connection of the output connection 12, and only the other electrical phases L2, L3 have switching elements S2, S3.

[0039] A charging circuit 4 can be arranged at the output connection 12 , which converts, for example, a provided single-phase or multi-phase AC voltage into a DC voltage which is suitable for charging the electrical energy storage device 5 .

[0040] Figure 5 A schematic diagram of a basic circuit diagram of a charging device for charging electrical energy storage device 5 according to another specific embodiment is shown. Figure 4 The embodiment shown in corresponds largely to the previously described embodiment and differs from the previously described embodiment in particular in that a series circuit consisting of a first capacitor element C1, a first inductive filter element I1, a second capacitor element C2, a second inductive filter element I2 and a third capacitor element C3 is provided in the filter device 1. Each of the capacitive and inductive elements C1, C2, C3 and I1, I2 can correspond to the corresponding element already described above. Therefore, a detailed illustration of the capacitor elements C1, C2, C3 and the individual capacitors in the inductive elements I1, I2 is omitted in this illustration.

[0041] Furthermore, for example, a voltage detector 14 can also be optionally provided. This voltage detector 14 can monitor, for example, the voltage at the phase connections of the input connection 11. If a significant voltage, in particular a voltage higher than a predetermined threshold value, is detected at one of the phase connections, the switching device 2 can then actuate the corresponding switching element S1, S2, S3 in order to connect the corresponding phase L1, L2, L3 to the corresponding phase connection of the output connection 12. In this way, the circuit configuration can be automatically adjusted according to the voltage conditions present at the input connection 11.

[0042] The charging device described above for charging the electrical energy storage device 5 can be used in particular to charge a traction battery for a vehicle that is driven completely or at least partially electrically.

[0043] In summary, the invention relates to a connection for a charging circuit for charging an electrical energy storage device by means of a single-phase or multi-phase AC voltage. For this purpose, it is provided that a filter device is provided for suppressing interference signals at the input before switching between single-phase or multi-phase charging processes. In this way, when switching between single-phase or multi-phase charging, the properties of the filter device, in particular the capacitive properties, are not affected by the circuit configuration.

Claims

1. A connection device for a device for charging an electrical energy storage device (5), comprising: An input connection (11) with a plurality of phase connections, wherein the input connection (11) is designed to be connected selectively either to a single-phase electrical energy source or to a multi-phase electrical energy source (3); an output connection (12) with a plurality of phase connections, wherein the output connection (12) is designed to be connected to a device (4) for charging an electrical energy storage device (5); A switching device (2) which is designed to selectively electrically connect one or more electrical phases (L1, L2, L3) of the input connection (11) to corresponding phase connections of the output connection (12); and A filter device (1), the filter device being designed to filter out electrical interference signals on an electrical connection portion between the input connector (11) and the output connector (12), The filter device (1) is electrically arranged between the input connection (11) and the switching device (2). It is characterized in that In the case where the charging voltage is provided only on one phase, the single-phase charging voltage can be provided on all phase connections of the output connections (12) for connecting the device (4) by means of corresponding switch positions in the switching device (2).

2. A connecting device according to claim 1, wherein the filtering device (1) comprises at least one first Y-type capacitor assembly, wherein capacitor elements (Cy) are respectively arranged between the electrical phases (L1, L2, L3) and the reference potential (PE) in the first Y-type capacitor assembly.

3. The connection device according to claim 1 or 2, wherein the filtering device (1) comprises a series circuit consisting of a first Y-type capacitor assembly, a first inductive filtering element (I1) and a second Y-type capacitor assembly.

4. A connection device according to any one of claims 1 to 3, wherein the filtering device (1) comprises a series circuit consisting of a first Y-type capacitor assembly, a first inductive filtering element (I1), a second Y-type capacitor assembly, a second inductive filtering element (I2) and a third Y-type capacitor assembly.

5. The connection device according to any one of claims 1 to 3, comprising a voltage detector (14) which is designed to detect the voltage at the phase connection of the input connection (11), The switching device (2) is designed to electrically connect the corresponding phase connection of the input connection (11) to the corresponding phase connection of the output connection (2) when the voltage at the corresponding phase connection of the input connection (11) exceeds a predetermined threshold value.

6. A charging device for charging an electrical energy storage device (5), comprising: A connection device according to any one of claims 1 to 5; and A device (4) for charging the electrical energy store (5) is designed to charge the electrical energy store (5) using a single-phase or multi-phase AC voltage provided at an input connection (11) of the connection device.

7. Electric vehicles, having: Electric drive system; an electrical energy storage device (5); and A charging device for charging the electrical energy storage device (5) according to claim 6.

Images