Energy storage system

Abstract

The present invention discloses an energy storage system for storing electrical energy, comprising at least one energy storage device, at least one pulse generator capacitor, a coupling switch assembly, and a control unit. The energy storage device is charged from at least one electrical energy source during charging operation and supplies power to at least one energy consumer during power feeding operation. The pulse generator capacitor is used to generate functional test energy pulses. The coupling switch assembly selectively couples or decouples the at least one pulse generator capacitor from the energy storage system. The control unit controls the coupling switch assembly such that, in the decoupling switching state of the coupling switch assembly, the at least one pulse generator capacitor is decoupled from the energy storage system, and in the coupling switching state of the coupling switch assembly, the at least one pulse generator capacitor is coupled to the energy storage system for charging and / or discharging the at least one pulse generator capacitor.

Description

Technical Field

[0001] The present invention relates to an energy storage system, which can store electrical energy, for example, in a vehicle, particularly an electric vehicle, to power various electrical energy consumers during their operation, and can be charged from at least one electrical energy source. Background Technology

[0002] In vehicles, especially electric vehicles, so-called supercapacitors (SCAPs) are used to store electrical energy. Compared to traditional battery storage devices, supercapacitors have the advantages of being able to be charged very quickly and releasing stored electrical energy very quickly. Therefore, supercapacitors are particularly suitable for use in conjunction with consumers that have high energy demands for very short periods, or with sources that can provide large amounts of energy (i.e., high charging power) for short periods. Summary of the Invention

[0003] The object of the present invention is to provide (particularly in a vehicle) an energy storage system for storing electrical energy and a method for operating the energy storage system, wherein the energy storage system and the method can generate defined energy pulses in a simple manner and method to generate information about the state of the energy storage system and / or the state of system regions that cooperate with the energy storage system.

[0004] According to a first aspect of the invention, the objective is achieved by an energy storage system (particularly in a vehicle) for storing electrical energy, the energy storage system comprising:

[0005] At least one energy storage device, which is charged from at least one electrical energy source during charging operation and feeds at least one electrical energy consumer during power feeding operation;

[0006] At least one pulse generator capacitor, said pulse generator capacitor being used to generate a functional test energy pulse;

[0007] A coupling switch assembly that selectively couples or decouples the at least one pulse generator capacitor from the energy storage system;

[0008] A control unit is configured to control the coupling switch assembly such that, in a decoupled switching state, the at least one pulse generator capacitor is decoupled from the energy storage system, and in a coupled switching state, the at least one pulse generator capacitor is coupled to the energy storage system for charging and / or discharging the at least one pulse generator capacitor.

[0009] The present invention utilizes the following effect: based on the charging state of the pulse generator capacitor, or based on the potential present in the energy storage system or a system coupled thereto (such as, for example, the vehicle's electrical grid), when such a pulse generator capacitor is coupled or disconnected, a pulse is generated due to the spontaneous potential shift at this time. This pulse can be used to infer the state (e.g., aging state), connection quality, etc. of different system regions in the energy storage system or coupled thereto by analyzing and processing their responses to the appearance of this pulse.

[0010] In order to integrate the function of generating functional test energy pulses into the energy storage system, it is proposed that: at least one energy storage unit includes a plurality of supercapacitors arranged in series with respect to each other, and at least one of the plurality of supercapacitors arranged in series with respect to each other constitutes a first pulse generator capacitor and at least one of the plurality of supercapacitors arranged in series with respect to each other does not constitute a pulse generator capacitor.

[0011] Here, it can be specified that the at least one supercapacitor constituting the first pulse generator capacitor can be coupled to and decoupled from the at least one supercapacitor that does not constitute the pulse generator capacitor by means of a coupling switch assembly.

[0012] In order to enable the coupling and decoupling of the at least one supercapacitor constituting the pulse generator capacitor with one or more supercapacitors not constituting the pulse generator capacitor, it can be specified that the coupling switch assembly includes:

[0013] At least one first switch, the first switch being configured to couple the at least one supercapacitor constituting the first pulse generator capacitor to the at least one supercapacitor not constituting the pulse generator capacitor in a coupling switch state and to decouple the at least one supercapacitor constituting the first pulse generator capacitor from the at least one supercapacitor not constituting the pulse generator capacitor in a decoupling switch state.

[0014] and

[0015] At least one second switch, the second switch being configured to close the capacitor bypass circuit connected in parallel with the at least one supercapacitor constituting the first pulse generator capacitor in a decoupling switch state and to disconnect the capacitor bypass circuit in a coupling switch state.

[0016] Alternatively or additionally, when integrating a capacitor used as a pulse generator into at least one accumulator, it may be specified that: a circuit breaker is provided for selectively coupling and decoupling the at least one accumulator from the accumulator system output interface; a circuit breaker bypass circuit is provided in parallel with the circuit breaker; and at least one second pulse generator capacitor disposed in the circuit breaker bypass circuit can be coupled to and decoupled from the at least one accumulator and / or the accumulator system output interface by means of the coupling switch assembly. By coupling such a positioned pulse generator capacitor into the accumulator system when connected to its disconnected position, pulses usable for functional verification are generated in the accumulator system or the coupled system by spontaneously charging a previously substantially discharged second pulse generator capacitor or by spontaneously discharging a second pulse generator capacitor previously charged to a relatively high potential, for example, by a voltage source provided for this purpose.

[0017] In one integration scheme of the pulse generator capacitor to the circuit breaker bypass circuit, the coupling switch assembly may include a third switch between the at least one second pulse generator capacitor and the at least one energy storage device and / or a fourth switch between the at least one second pulse generator capacitor and the energy storage device system output interface in the circuit breaker bypass circuit.

[0018] In another integration scheme where the pulse generator capacitor can be optionally or additionally implemented in the energy storage system, at least one third pulse generator capacitor can be coupled to and decoupled from the energy storage system by means of the coupling switch assembly. This means that the third pulse generator capacitor is not integrated into the energy storage system, for example, as a supercapacitor, but is externally positioned relative to the at least one energy storage system. This provides the possibility of generating pulses in the energy storage system via such a third pulse generator, which can, for example, be used to perform functional testing on the at least one energy storage system.

[0019] In order to selectively couple the third pulse generator capacitor, which is configured in this way, into or out of the energy storage system, the coupling switch assembly may include a fifth switch, which is used to couple the at least one third pulse generator capacitor to the energy storage system in a coupling switch state and to decouple the at least one third pulse generator capacitor from the energy storage system in a decoupling switch state.

[0020] In another variant, alternatively or additionally, at least one fourth pulse generator capacitor can be coupled to and decoupled from the energy storage system output interface by means of the coupling switch assembly. In particular, when the at least one energy storage unit is decoupled from the energy storage system output interface via a circuit breaker, the functional test energy pulse generated by this fourth pulse generator capacitor can be directly directed from the energy storage system to a system cooperating with the energy storage system, such as an onboard electrical system in a vehicle, and there, the functional test energy pulse can be used for functional testing by monitoring the responses of different system regions.

[0021] In this configuration, the coupling switch assembly may include a sixth switch, which is used to couple the at least one fourth pulse generator capacitor to the energy storage system output interface in a coupling switch state and to decouple the at least one fourth pulse generator capacitor from the energy storage system output interface in a decoupling switch state.

[0022] The present invention also relates to a method for generating a function test energy pulse in an energy storage system constructed according to the present invention, wherein, in order to generate the function test energy pulse:

[0023] By switching the coupling switch assembly to a coupling switch state, at least one pulse generator capacitor, which is decoupled from the energy storage system via the coupling switch assembly, is coupled to the energy storage system. The coupling switch state then couples the at least one pulse generator capacitor, which is decoupled from the energy storage system, to the energy storage system.

[0024] and / or

[0025] By switching the coupling switch assembly to a decoupling switch state, at least one pulse generator capacitor coupled to the energy storage system via the coupling switch assembly is decoupled from the energy storage system. The decoupling switch state decouples the at least one pulse generator capacitor coupled to the energy storage system from the energy storage system.

[0026] Furthermore, the present invention relates to an on-board electrical grid system for a vehicle, the on-board electrical grid system including an energy storage system constructed according to the present invention, the on-board electrical grid system further including at least one energy consumer to feed power from the energy storage system and at least one electrical energy source for charging the at least one energy storage system. Attached Figure Description

[0027] The present invention will now be described in detail with reference to the accompanying drawings. In the drawings:

[0028] Figure 1 A schematic diagram of an onboard electrical system for a vehicle is shown.

[0029] Figure 2 Show Figure 1 A detailed view of the energy storage system of the vehicle's electrical grid system;

[0030] Figure 3 Another detailed view of the energy storage system in an alternative design is shown;

[0031] Figure 4 Another detailed view of the energy storage system in an alternative design is shown. Detailed Implementation

[0032] exist Figure 1 The diagram shows a schematic of an onboard electrical grid system 10 for a vehicle. The onboard electrical grid system 10 includes an energy storage system 12 that can store energy provided by at least one electrical energy source 14 and can feed power to at least one electrical energy consumer 16. For example, in an electrically powered vehicle, the at least one electrical energy source may include a generator (e.g., one or more electric motors operating as generators during vehicle braking) and one or more actuators installed in the vehicle (e.g., steering actuators, etc.). The electrical energy source 14 may also include a grid interface by which the electrically powered vehicle can be connected to a voltage grid or charging station. The at least one electrical energy consumer 16 may include, for example, a traction motor of an electrically powered vehicle, an electric steering system, or its electrically powered actuators, or other consumers present in the vehicle (e.g., electrically powered heating devices, audio / communication systems, etc.).

[0033] The energy storage system 12, as a core component, includes an energy storage unit 20, which in the illustrated embodiment includes a plurality of supercapacitors 18. The supercapacitors 18 may be connected in parallel and / or in series with each other. The energy storage system 12 may, for example, include multiple such energy storage units 20, each comprising one or more supercapacitors 18. The energy storage system 12, or another energy storage system present in the vehicle electrical grid system 10, may also include one or more battery energy storage units, particularly capable of storing sufficient energy for the electric traction motor of an electrically powered vehicle.

[0034] The energy storage system 12, including multiple supercapacitors 18, may also include a power converter 22 configured as a DC / DC converter and / or a circuit breaker 24. If such a circuit breaker 24 is provided, the power converter 22 can be positioned between the circuit breaker and the energy storage system 20. The power converter 22 and the circuit breaker 24 are controlled by a control unit 26, allowing the operation or state of the power converter and the circuit breaker to be adjusted in the manner and manner described below. For this purpose, the control unit 26 is supplied with, for example, information representing the charging state of the energy storage system 20, information representing the voltage of the energy storage system 20 and / or the current flow to or from the energy storage system 20, and information representing, for example, the on-board grid voltage present in the on-board grid 28 coupled to the energy storage system 12 during charging operation or also during power feeding operation, or the current flowing between the power converter 22 and the on-board grid 28.

[0035] In the power supply operation (in which the energy storage system 12 supplies electrical energy to at least one energy consumer 16 of the vehicle electrical network 28), the circuit breaker 24 is in principle in its closed state, such that this circuit breaker establishes an electrical connection between the energy storage 20 and the vehicle electrical network 28 via a power converter 22 configured as a DC / DC converter. If the power converter 22 is a variable power converter with variable output power or output voltage, the control unit 26 can operate the power converter 22 such that it converts the voltage applied to the energy storage 20 on its energy storage-side connection region 30 to a voltage set for or suitable for the vehicle electrical network 28 on its vehicle electrical network-side connection region 32. Here, it is important to consider that, particularly when the energy storage 20 is designed with multiple supercapacitors 18, the voltage supplied by the energy storage 20 decreases with the discharge process. This allows the power converter 22 to be manipulated to provide a substantially constant voltage at its on-board grid connection region 32, thereby providing a substantially constant output voltage of the energy storage system 12 to the on-board grid 28 and thus also a substantially constant feed power, which can be represented, for example, by the current flowing from the power converter 22 into the on-board grid 28 during the feed operation. In principle, the power converter 22 can also be configured as a fixed power converter, such that it has a defined conversion ratio for voltage at the energy storage side connection region 30 and the on-board grid side connection region 32.

[0036] During the charging operation, i.e., when the energy storage unit 20 is partially or completely discharged, the charging power provided by the at least one electrical energy source 14 can be used to charge the energy storage unit 20 when electrical energy is provided by the at least one electrical energy source 14 (i.e., during braking of an electrically operated vehicle) or when electrical energy is fed back from an electrically driven actuator. In this state, the circuit breaker 24 is also operated so that it is in its closed state to establish a connection between the on-board electrical grid side connection area 32 of the power converter 22 and the on-board electrical grid 28. The charging power provided by the at least one electrical energy source 14 (which can be represented, for example, by the current flowing from the on-board electrical grid 28 to the power converter 22 during charging operation) is converted by the power converter 22 in such a way that an energy flow suitable for the energy storage unit 20 is realized between the energy storage unit side connection area 30 and the energy storage unit 20, for example, by providing a charging voltage suitable for the energy storage unit 20 on the energy storage unit side connection area 30.

[0037] To test the functionality of different system areas of the vehicle-mounted electrical grid system 10, and particularly to test the quality of electrical connections, functional test energy pulses are generated in the manner and method described below. By analyzing and processing the system response to, for example, such functional test energy pulses introduced into the vehicle-mounted electrical grid 28 or the energy storage device 20, the state or functionality of different system areas can be inferred.

[0038] Figure 2 The energy storage device 20 is shown in detail, having supercapacitors 18a, 18b, 18c, and 18d disposed therein. Among the series-connected supercapacitors 18a, 18b, 18c, and 18d, for example, the last supercapacitor 18d constitutes a first pulse generator capacitor P1, which can be selectively coupled to or decoupled from the supercapacitors 18a, 18b, and 18c that do not constitute the pulse generator capacitor by means of a coupling switch assembly 34. For this purpose, a capacitor bypass line 36 is connected in parallel with the first pulse generator capacitor P1. The coupling switch assembly 34 includes a first switch S1, by which supercapacitor 18b, or pulse generator capacitor P1, can be coupled to or decoupled from the other supercapacitors 18a, 18b, and 18c. A second switch S2 is provided in the capacitor bypass circuit 36. The second switch can be used to selectively disconnect the capacitor bypass circuit 36 ​​or connect the capacitor bypass circuit to the conducting state that bypasses the first pulse generator capacitor P1.

[0039] The coupling switch assembly 34, or its switches S1 and S2, is under the control of the control unit 26, which supplies information about the individual cell voltages present in each of the supercapacitors 18a, 18b, 18c, and 18d via corresponding sensing mechanisms. Information about the current in the energy storage unit 20 is also supplied to the control unit 26.

[0040] In the coupling switch state of coupling switch assembly 34 (in which supercapacitor 18d, acting as the first pulse generator capacitor P1, is coupled to the other supercapacitors 18a, 18b, 18c), the first switch S1 is in its closed state and the second switch S2 is in its open state. In the decoupling switch state of coupling switch assembly 38, which decouples supercapacitor 18d, or the first pulse generator capacitor P1, from the other supercapacitors 18a, 18b, 18c, the first switch S1 is in its open state and the second switch S2 is in its closed state, such that the last supercapacitor 18c in the series-connected sequence is grounded via capacitor bypass line 36.

[0041] By decoupling supercapacitor 18d, which is charged to the same individual cell voltage as supercapacitors 18a, 18b, and 18c under normal conditions, the output voltage of the energy storage 20, obtained by summing the voltages of the individual cells, spontaneously changes. This change in the voltage, or output potential, of the energy storage 20 can be identified as a voltage pulse in the energy storage system 12 or the on-board electrical network 28 coupled to the energy storage system. By analyzing and processing information about the individual cell voltages and current flows in the energy storage 20, information about the generation of the energy pulse and the temporal variation of the energy pulse are available when the first pulse generator capacitor P1 is decoupled. This information can be used to analyze and process the functions of the system regions contained therein by monitoring, for example, the system responses in the on-board electrical network 28.

[0042] By selectively coupling and disconnecting the first pulse generator capacitor P1, it is possible to generate this functional monitoring energy pulse without having to provide a separate structural component for generating such a pulse. Thus, in particular, the functional monitoring energy pulse can be used to analyze the function of the system or the function of its individual components by monitoring the system response in the vehicle electrical network 28.

[0043] exist Figure 3 An alternative design scheme is shown in the figure. Figure 3In the energy storage system 12, a circuit breaker bypass line 38 is provided in parallel with the circuit breaker 24, and preferably also with the power converter 22. A second pulse generator capacitor P2 is provided in the circuit breaker bypass line 38. A third switch S3 and a fourth switch S4 are provided on both sides of the second pulse generator capacitor P2 in the circuit breaker bypass line 38. If both switches S3 and S4 of the coupling switch assembly 34 are in their open state, the second pulse generator capacitor P2 is decoupled from the energy storage system 12. When switches S3 and S4 are closed, the second pulse generator capacitor P2 is coupled to the energy storage system 12.

[0044] By coupling or disconnecting the second pulse generator capacitor P2, a functional test energy pulse can be generated when the circuit breaker 24 is in its open position, based on its charging state. If, for example, the second pulse generator capacitor P2 is substantially completely discharged, closing switches S3 and S4 (i.e., causing the coupling switch state of the coupling switch assembly 34) induces a spontaneous charging current flowing into the second pulse generator capacitor P2. If the second pulse generator capacitor P2 is charged, for example, by a voltage source separately provided to it to a voltage level that, together with the voltage level of the energy storage 20, results in a voltage level above that of the vehicle electrical network 28, then closing switches S3 and S4 and thus establishing the coupling switch state of the coupling switch assembly 34, in the case of the spontaneous discharge of the second pulse generator capacitor P2, results in a pulse in the energy storage system 12, which propagates in this energy storage system and also to the vehicle electrical network 28, and is also used for functional monitoring.

[0045] Figure 4 A design is shown in which the third pulse generator capacitor P3 can be selectively coupled to or decoupled from the energy storage system 12 via a fifth switch S5 to a line region between the energy storage 20 and the energy storage side connection region 30 of the circuit breaker 24. When the circuit breaker 24 is open, a current can be generated from or into the third pulse generator capacitor P3 when the switch S5 is closed, depending on the charging state of the third pulse generator capacitor P3. This generates a pulse in this region of the energy storage 12 that can be used to perform a functional test on the energy storage 20.

[0046] Alternatively or additionally, in this energy storage system 12, the fourth pulse generator capacitor P4 can be coupled or decoupled from the line region between the vehicle-mounted electrical grid side connection region 32 and the energy storage system output interface 40, preferably between the power converter 22 and the energy storage system output interface 40, via the sixth switch S6 of the coupling switch assembly 34. When the circuit breaker 24 is open, opening or closing the sixth switch S6 results in a pulse, which can be used for functional verification in the vehicle-mounted electrical grid 28 connected to the energy storage system 12.

[0047] exist Figure 4 In the embodiment shown, during normal operation, the pulse generator capacitors P3 and P4, for example grounded, can be charged using the vehicle grid voltage or the output voltage of the energy storage unit 20. Alternatively, a separate voltage source can be provided in conjunction with these pulse generator capacitors P3 and P4, through which these pulse generator capacitors can be charged, for example, to a voltage level above the vehicle grid voltage or the voltage of the energy storage unit 20, so that a functional test energy pulse can be generated by subsequently closing switches S5 and S6.

[0048] Finally, it should be noted that the front reference of the pulse generator capacitor can also be used. Figures 2 to 4 The different design schemes or positioning schemes described can be arbitrarily combined with each other in order to expand the functionality used for functional verification.

Claims

1. An energy storage system for storing electrical energy, particularly an energy storage system in a vehicle, the energy storage system comprising: At least one energy storage device (20) is charged from at least one electrical energy source (14) during charging operation and supplies power to at least one electrical energy consumer (16) during power feeding operation; At least one pulse generator capacitor (P1, P2, P3, P4) is used to generate a functional test energy pulse; A coupling switch assembly (34) selectively couples or decouples the at least one pulse generator capacitor (P1, P2, P3, P4) from the energy storage system (12); A control unit (26) is configured to control the coupling switch assembly (34) such that at least one pulse generator capacitor (P1, P2, P3, P4) is decoupled from the energy storage system (12) in the decoupled switching state of the coupling switch assembly (34) and coupled to the energy storage system (12) in the coupled switching state of the coupling switch assembly (34) for charging and / or discharging the at least one pulse generator capacitor (P1, P2, P3, P4).

2. The accumulator system of claim 1, wherein, At least one energy storage device (20) includes a plurality of supercapacitors (18) arranged in series with respect to each other, and at least one of the plurality of supercapacitors (18) arranged in series with respect to each other (18d) constitutes a first pulse generator capacitor (P1) and at least one of the plurality of supercapacitors (18) arranged in series with respect to each other (18a, 18b, 18c) does not constitute a pulse generator capacitor.

3. The accumulator system of claim 2, wherein, The at least one supercapacitor (18d) constituting the first pulse generator capacitor (P1) can be coupled to and decoupled from the at least one supercapacitor (18a, 18b, 18c) that does not constitute the pulse generator capacitor by means of a coupling switch assembly (34).

4. The accumulator system of claim 3, wherein, The coupling switch assembly (34) includes: At least one first switch (S1) is configured to couple at least one supercapacitor (18d) constituting the first pulse generator capacitor (P1) to at least one supercapacitor (18a, 18b, 18c) not constituting the pulse generator capacitor in a coupling switch state and to decouple at least one supercapacitor (18d) constituting the first pulse generator capacitor (P1) from at least one supercapacitor (18a, 18b, 18c) not constituting the pulse generator capacitor in a decoupling switch state. and At least one second switch (S2) is used to close the capacitor bypass circuit (36) connected in parallel with the at least one supercapacitor (18d) constituting the first pulse generator capacitor (P1) in a decoupling switch state and to disconnect the capacitor bypass circuit (36) in a coupling switch state.

5. The accumulator system of any one of claims 1 to 4, wherein, A circuit breaker (24) is provided for selectively coupling and decoupling the at least one accumulator (20) from the accumulator system output interface (40). A circuit breaker bypass line (38) is provided in parallel with the circuit breaker (24). At least one second pulse generator capacitor (P2) provided in the circuit breaker bypass line (38) can be coupled to and decoupled from the at least one accumulator (20) and / or the accumulator system output interface (40) by means of the coupling switch assembly (34).

6. The accumulator system of claim 5, wherein, The coupling switch assembly (34) includes a third switch (S3) between the at least one second pulse generator capacitor (P2) and the at least one energy storage device (20) and / or a fourth switch (S4) between the at least one second pulse generator capacitor (P2) and the energy storage device system output interface (40) in the circuit breaker bypass line (38).

7. The accumulator system of any one of claims 1 to 6, wherein, At least one third pulse generator capacitor (P3) can be coupled to the energy storage unit (20) and decoupled from the at least one energy storage unit (20) by means of the coupling switch assembly (34).

8. The accumulator system of claim 7, wherein, The coupling switch assembly (34) includes a fifth switch (S5) for coupling the at least one third pulse generator capacitor (P3) to the energy storage unit (20) in a coupling switch state and for decoupling the at least one third pulse generator capacitor (P3) from the energy storage unit (20) in a decoupling switch state.

9. The accumulator system of any one of claims 1 to 8, wherein, At least one fourth pulse generator capacitor (P4) can be coupled to and decoupled from the energy storage system output interface (40) by means of the coupling switch assembly (34).

10. The accumulator system of claim 9, wherein, The coupling switch assembly (34) includes a sixth switch (S6) for coupling the at least one fourth pulse generator capacitor (P4) to the energy storage system output interface (40) in a coupling switch state and for decoupling the at least one fourth pulse generator capacitor (P4) from the energy storage system output interface (40) in a decoupling switch state.

11. Method of generating a function check energy pulse in an accumulator system according to any one of claims 1 to 10, wherein To generate a functional test energy pulse: By switching the coupling switch assembly (34) to the coupling switch state, at least one pulse generator capacitor (P1, P2, P3, P4) decoupled from the energy storage system (12) by means of the coupling switch assembly (34) is coupled to the energy storage system (12). The coupling switch state couples the at least one pulse generator capacitor (P1, P2, P3, P4) decoupled from the energy storage system (12) to the energy storage system (12). and / or By switching the coupling switch assembly (34) to the decoupling switch state, at least one pulse generator capacitor (P1, P2, P3, P4) coupled to the energy storage system (12) via the coupling switch assembly (34) is decoupled from the energy storage system (12). The decoupling switch state decouples the at least one pulse generator capacitor (P1, P2, P3, P4) coupled to the energy storage system (12) from the energy storage system (12).

12. An on-board electrical grid system for a vehicle, the on-board electrical grid system comprising an energy storage system (12) according to any one of claims 1 to 10, the on-board electrical grid system further comprising at least one energy consumer (16) for feeding power from the energy storage system (12) and at least one electrical energy source (14) for charging the at least one energy storage system (20).

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