WO2018233957A1

WO2018233957A1 - Electric energy supply device with a nominal capacity, and method for providing a nominal capacity in an electric energy supply device

Info

Publication number: WO2018233957A1
Application number: PCT/EP2018/063113
Authority: WO
Inventors: Michael Hinterberger; Berthold Hellenthal; André Blum
Original assignee: Audi Ag
Priority date: 2017-06-23
Filing date: 2018-05-18
Publication date: 2018-12-27
Also published as: DE102017210612A1

Abstract

The invention relates to an electric energy supply device (10) with a respective nominal capacity which is provided by a plurality of usage units (12). Each usage unit has an individual nominal capacity, for example for the current, voltage, or capacitance. A controller (19) is designed to control an energy exchange (E) between the energy supply device (10) and at least one externally connected load or generator (100). The sum of each individual nominal capacity of the usage units (12) is greater than the respective nominal capacity. The controller (19) is limited to the respective nominal capacity during the energy exchange (E).

Description

An electric power supply having a nominal nominal capacity and methods of providing a nominal nominal capacity in an electrical power delivery device

DESCRIPTION:

The invention relates to an electric power supply device in which a plurality of use units is provided. The energy supply device may be, for example, an electric stationary storage or a vehicle battery for an electric vehicle, in which case battery modules may be provided as use units. The energy delivery device has a nominal nominal capacity that is provided outwardly for at least one connected device. The invention also includes a method for providing the nominal nominal capacity by means of the electrical energy delivery device.

An energy delivery device may be provided, for example, for a charging station for charging electrically driven motor vehicles. However, an energy supply device can, for example, itself also be designed as a traction battery for an electrically drivable motor vehicle, ie as a mobile energy store.

An energy supply device with a plurality of utilization units for storing electrical energy is known, for example, from US 2006/0092583 A1. The energy delivery device described therein can optionally switch the utilization units in parallel between two busbars or interconnect them to add up the electrical voltages of the utilization units as a series connection between the busbars. For an energy supply device, a nominal value or a nominal capacity, for example 1 kWh, can be indicated for a specific parameter, for example the energy storage capability. In an energy delivery device, it is interesting that it can be operated reliably and for as many hours of operation with the nominal capacity. Especially for this However, to use robust payload units makes a power delivery device expensive to manufacture. Another alternative is as gentle as possible operation of the Nutzzeinheiten, but in turn limits the performance of an energy delivery device.

The invention has for its object to provide a cost-effective, yet reliable in operation energy delivery device.

The object is achieved by the subject matter of the independent patent claims. Advantageous developments of the invention are described by the dependent claims, the following description and the figures.

The invention provides an electrical energy delivery device that provides a respective nominal rating or nominal nominal capacity with respect to at least one predetermined characteristic, such as storage capacity and / or rated electrical power. In this case, nominal capacity refers to that information which can be provided in normal operation or without time limitation or damage if a device external to the device is connected to the energy supply device and operated therewith. The respective rated capacity with respect to the at least one electrical parameter (that is, for example, the storage capacity and / or the electric power) is provided by means of a plurality of use units. Such a use unit may for example contain at least one battery cell or a battery cell module with a plurality of battery cells or a capacitor or a capacitor arrangement with a plurality of capacitors or solar cells or fuel cells. Of course, each use unit has an individual capacity with regard to the respective parameter, that is, for example, an individual memory capacity and / or a single nominal power.

A control device of the energy delivery device is configured to control an energy exchange between the energy supply and at least one device external to the device, which may be connected to the energy delivery device. Energy exchange means on the one hand the energy delivery to the device and on the other hand the energy consumption from the device. In order to make the energy supply device more reliable and durable, it is provided according to the invention that the sum of said respective individual capacities in the utilization units is greater than the respective nominal capacity of the energy delivery device. In other words, therefore, the utilization units, for example, in the sum of a larger storage capacity, as indicated by the nominal capacity of the energy delivery device to the outside. Additionally or alternatively, the sum of the individual rated outputs of the utilization units may be greater than the outwardly indicated nominal output of the energy delivery device as a whole. The control device is accordingly set up to limit the at least one parameter to the respective nominal rated capacity during said energy exchange. In other words, although within the energy delivery device by the utilization units with respect to the at least one characteristic (eg storage capacity and / or power), the sum of the individual capacities is greater than the respective nominal capacity, but the control device limits the operation of the energy delivery device, that these only the respective nominal capacity to the outside, that is, to the at least one device out, provides. The advantage of the invention is that each use unit can be operated below its individual nominal capacity, ie the load or wear of each use unit may be lower than would arise if each use unit were operated with its individual nominal capacity. This reduces the probability that a user unit will fail due to wear. Overall, therefore, results in a gentle operation of the Nutzzeinheiten compared to an operation in their Einzelnennkapazität. In this way we achieved an extension of the service life. A further advantage is that in the event of a failure of a use unit with the energy delivery device as a whole, the nominal nominal capacity can still be provided, so that the failure of a use unit does not lead to the nominal nominal capacity of the energy delivery device decreasing. The energy supply device can therefore continue to operate without restriction even in the event of a failure of one or more use units.

The invention also includes refinements, resulting in additional benefits. The at least one parameter, which is limited to the respective nominal capacity, may be the electrical storage capacity of the energy delivery device and / or the maximum electrical power and / or the maximum electrical current. By limiting these parameters, a gentle operation of utilization units can be achieved.

Each use unit may in each case comprise at least one battery cell or a battery cell module or a composite of a plurality of battery cell modules and / or at least one fuel cell and / or at least one solar panel and / or at least one capacitor. A use unit may also comprise a generator.

For a specific energy exchange process, the question arises as to how the user units are interconnected with the at least one connected device. The control device may be configured to electrically connect more use units to the at least one control unit for the energy exchange process than is necessary for providing the respective nominal capacity of the at least one characteristic variable. As a result, in the described manner, each use unit can be operated with a lower load than corresponds to its individual capacity.

A development provides that the control device is set up to operate the energy delivery device for a predetermined period of time with its gross capacity representing the sum of the individual nominal capacities. As a result, a so-called boost mode or turbo mode can be realized. The duration may be in the range of 1 s to 1 min.

The control device can be set up to not use all user units in the case of a plurality of energy exchange processes carried out in succession, but only to electrically couple some of the usage units to the connected at least one device. Now you can durchrotiert. In other words, in this case, the control device is set up to select, for each of the energy exchange processes, the respective utilization units to be connected according to a predetermined replacement instruction. A possible substitution rule can be achieved with the "Round Robin" algorithm Additionally or alternatively, for example, for a given energy exchange operation, the replacement instruction may select those which have the least wear and tear Use unit, for example, quantized by their electrical impedance. The greater the impedance of a utility unit, the greater its wear or wear has progressed. In general, wear can be expressed as so-called SoH (State of Health), as is known from the prior art. Another wear-dependent wear value can also be defined and determined, for example, by simple tests. The replacement rule results in a uniform wear of the use units, so that the likelihood decreases that sporadically a single unit fails.

The control device may be configured to determine the respective wear value of each use unit and to deactivate those of the use units whose wear value fulfills a predetermined wear criterion by cutting them off electrically. In other words, these use units are excluded from the energy exchange. At a degree of wear that meets the wear criterion, so a use unit is switched out. In the context of managing digital memory cells, this is known as Bad Block Management. This approach is transferred by the invention to electrical power units. The advantage of such a bath block management is that the operation of the energy delivery device does not have to take into account the weakest, that is to say the most worn, use units, for example in the form of load balancing, because these utilization units are taken out of operation.

In this case, however, the control device is preferably set up to put at least one of the used-out use units back into operation by electrical coupling, so that it is thus again involved in the energy exchange. This happens if the wear value of the use unit fulfills a predetermined similarity criterion in comparison with the respective wear value of the use units still in operation. In other words, it is waited until all other use units are also worn so far that the use units again have a similar degree of wear. Thus, the use units again have similar electrical properties (in the sense of the similarity criterion), so that a common operation is possible again, that is, for example, a load balancing does not lead to an excessive restriction of operation of the use unit with the lowest wear value. The similarity criterion may say, for example, that maximum difference in terms of at least one parameter in a range of 10 percent to 100 percent. An underlying parameter may be, for example, the impedance of the use unit. In other words, the similarity criterion for the wear values may indicate that their difference must be within a range of 10 percent to 100 percent. For example, an average value of all wear values can be formed and then the difference to this mean value can be calculated. It is also possible, for example, to specify or determine the maximum and the minimum wear value, and the difference then relates to the maximum and the minimum wear value.

A use unit can also fail completely, that is broken. For such a case, the control device can be set up to recognize a defective use unit and to disconnect it electrically from the remaining use units. The recognition of a defective use unit can be done by means of the prior art. For example, an electric current generated by the use unit can be checked for a defect criterion. For example, it can be specified as a defect criterion that a charging current of the utilization unit is smaller than a predetermined threshold value. However, if a utility unit is electrically isolated or disconnected, it may be replaced during operation of the energy delivery device. Accordingly, in this development, the control device is set up to electrically couple this use unit to the remaining use units during operation of the energy supply device after replacement of the defective use unit by a new use unit. As a result, it is thus possible to replace a defective use unit in ongoing operation of the energy delivery device, so that the energy delivery device for replacement can not be taken out of service, but can continuously carry out an energy exchange.

The power supply device has the following preferred structure. In each case, some of the use units are connected in a respective circuit branch or strand to a series circuit. Each strand is connected via a DC-DC converter (DC / DC converter) and at least one galvanically separable switching unit to a busbar arrangement of the energy delivery device. A galvanically isolating switching unit is a mechanical switching unit, for example a contactor or an arrangement of several contactors. In general, the DC-DC converter can be a boost converter or buck converter or an inverse converter. As a DC-DC converter, a buck converter is preferably used. Within each string, each use unit can also be switched individually. For this purpose, a bridging circuit is provided within each strand for each use unit. By means of the bypass circuit can be electrically bridged within the series circuit of the strand a use unit, so that it no longer contributes to the string current of the series circuit and also does not contribute to the strand voltage.

The energy delivery device performs the energy exchange via said busbar assembly. In other words, at least one strand is electrically connected by means of its galvanically separable switching units or by means of its individual switching unit with busbars of the busbar assembly, so that an electric current from the at least one strand on the busbar assembly can flow towards the at least one device, whereby the energy exchange takes place. In this case, the control device is set up to control the DC / DC converter and the at least one switching unit and the bypass circuits of each line in order to limit the at least one characteristic (that is, for example, the storage capacity and / or the electrical power).

The invention also includes a method of providing a respective nominal rated capacity of at least one predetermined electrical characteristic in an electrical power delivery device. The respective nominal capacity of the at least one electrical parameter is provided by means of a plurality of utilization units, each of which has a Einzelnennkapazität concerning the respective characteristic. The control device controls the energy exchange between the energy delivery device and the at least one apparatus external device, wherein it limits the energy exchange at least one parameter to the respective nominal capacity. Overall, however, the working units with the sum of their respective individual nominal capacities provide a gross capacity that is greater than the nominal nominal capacity of the at least one characteristic. This results in the advantageous effects described in terms of improving the longevity of the energy delivery device. Of course, it may be provided that the energy delivery device is operated for a predetermined period of time with its gross capacity. The duration may be in the range of 1 s to 1 min. In other words, a so-called boot operation can be provided. The sum of the individual nominal capacities thus represents a gross capacity of the energy delivery device. The nominal nominal capacity represents a net capacity, as it can be used or tapped externally from the point of view of the at least one device. This results in the energy delivery device overcapacity.

The invention also includes further developments of the method according to the invention, which have features as have already been described in connection with the developments of the energy delivery device according to the invention. For this reason, the corresponding developments of the method according to the invention are not described again here.

In the following an embodiment of the invention is described. This shows:

Fig. 1 is a schematic representation of an embodiment of the energy delivery device according to the invention; Fig. 2 is a schematic representation of a use unit of the power supply device of Fig. 1 with a bridging circuit.

The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention, which are to be considered independently of one another, which each further develop the invention independently of one another and thus also individually or in a different combination than the one shown as part of the invention. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

In the figures, functionally identical elements are each provided with the same reference numerals.

1 shows an electrical energy delivery device 10, which may be designed as an energy store or as a pure energy source or as a combination thereof. The energy delivery device 10 may be provided, for example, as a stationary storage for electrical energy. You can eg at a Be built road network. At least one device 100, for example an electrically drivable motor vehicle, can then be connected to the energy delivery device 10 in order, for example, to charge a traction battery of the motor vehicle by means of an energy exchange E. The power delivery device 10 may also be intended for use as a mobile or traction battery or solar storage. As traction battery can be connected to the power supply device such as an electric machine of a traction drive. In the charged state, the energy delivery device 10 can output at least 1 kW of electrical power and / or deliver at least 1 kWh of electrical energy.

In the energy supply device 10, several circuit branches or strings or strands 1 1 can be provided for the energy exchange E, wherein in each strand 1 1 more of the use units 12 can be connected to a series circuit 13. The utilization units 12 are thus combined in the energy delivery device 10, thus e.g. in a vehicle traction battery or in an electrical stationary storage. The energy delivery device 10 may comprise a housing in which the strands 1 1 and the busbar assembly 18 are arranged.

Each use unit 12 may each contain an electrical energy storage and / or a pure source of electrical energy. As energy storage, a use unit may be e.g. an electrochemical battery cell or a battery cell module with a plurality of battery cells or a capacitor or a capacitor arrangement with a plurality of capacitors. Examples of battery cells are those with the technology lithium-ion, lead, solid-state / solid state. Examples of suitable capacitors are double-layer capacitors (so-called supercaps (R)) having a capacity of preferably at least 1 mF, in particular at least 100mF). Examples of a pure source are each a fuel cell and a solar cell. As an energy source, a use unit 12 may be used e.g. a fuel cell or a fuel cell stack or a solar cell or a solar panel or a generator e.g. a power plant (e.g., a pumped storage power plant). A utilization unit 12 may also be provided with a parallel circuit of e.g. have multiple battery cells or battery cell modules.

Within each string 1 1, the technology used of the utilization units 12 is uniform, ie, for example, only battery modules or only solar cells are present. seen. Each strand 1 1 thus has use units 12 of the same technology, that is, for example, as a battery cell module, each a lithium-ion accumulator. But mixed technologies can be provided by different strands 11. As a result, the energy delivery device can be adapted to a purpose or to a required operating profile. For example, for the use of the energy delivery device 10 in the motor vehicle as a traction battery, for example, two strands of different technology may be provided, eg with a breakdown of the number of use units 12: 80% energy cells (large storage capacity), 20% power cells (more expensive, but larger power flow).

1, as shown in FIG. 1, in addition to the series circuit 13 of utilization units 12, a DC-DC converter 14, in each case a mechanical switching unit 15 at the strand ends 11 ', a measuring device 16 for a strand current I, and / or a voltage measuring device for detecting a sum voltage or phase voltage U of the strand 1 1.

Each DC-DC converter 14 can be designed in a manner known per se. In general, the DC-DC converter can be a boost converter or buck converter or an inverse converter. Each DC-DC converter 14 may in particular be a buck converter. Each switching unit 15 may be designed mechanically switching and is in particular galvanically separable. Each switching unit 15 may include a plurality of ON / OFF contactors or (as shown in FIG. 1) a contactor configured as a toggle switch (1-to-N multiplexer). By means of each switching unit 15, the respective strand end 1 1 'can be alternately connected and disconnected galvanically with strand connections 17. Each strand connection 17 constitutes an electrical connection to a busbar 18 '. The busbars 18' as a whole form a busbar arrangement 18 of independent busbars 18 '. Each strand connection 17 of a strand 1 1 can be connected to another busbar 18 'of the busbar assembly 18. Per strand end 1 1 '(positive pole and negative pole) can thus be provided several strand 17 connections to alternately connect the strand 1 1 to a plurality of different busbars 18' of the busbar assembly 18 or galvanically separated from each busbar 18 ' , By opening the two switching units 15 of a strand 1 1, this can thus be galvanically decoupled and also replaced during operation of the energy delivery device 10. Each strand 1 1 can provide a sum voltage or DC voltage U at the strand connections 17 by means of the series circuit 13. The DC voltage U may be a DC voltage (HV), which may be more than 60V, in particular more than 100V. However, it can also be provided that the DC voltage U is in the range of 8V to 60V. Between two bus bars 18 'is thus a DC voltage when a strand 1 1 is galvanically connected to them. Each strand 1 1 can be galvanically connected by means of its switching units 15 alternately with a respective pair of bus bars 18. The strand 1 1 can be galvanically connected by means of the switching units 15 alternately with a pair of busbars by a respective rod end 1 1 'is connected to a busbar 18' of the pair of busbars, so that the DC voltage U drops on the busbar pair.

The measuring unit 16 may also provide said total voltage measurement across the string 1 1 to detect the DC voltage U. For this purpose, the measuring unit 16 is preferably connected downstream of the DC-DC converter 14, as shown in FIG. 1, in order to enable a voltage regulation by means of the DC voltage converter 14. As will be explained in connection with FIG. 2, a single voltage measurement is still provided in each use unit 12.

About the busbar assembly 18, the at least one device 100 can be connected to the strands 1 1. By busbars 18 'of the busbar assembly 18 thus a bus bar matrix is formed, via which optionally at least one selected strand 1 1 can be electrically connected to a selected device 100, while at the same time another device with at least one other strand 1 1 can be electrically connected. The devices remain galvanically separated from each other.

Which strand 1 1 is electrically connected to which busbar 18 'can be determined by a control device 19. For this purpose, the control device 19 can determine a respective energy requirement and / or a respective power requirement of the at least one connected device 100 and then select at least one line 11 by means of which the demand can be met. The device 100 may itself communicate the requirement via a communication interface, for example, or it may be stored in the control device 19 as a fixed value, for example. The controller 19 may then connect the switching units 15 of each selected string 1 1 to the bus bars 18 'leading to the connected device 100. It can be provided in each case a further switching unit 15 'between each two strands 1 1 to switch two strands 1 1 in series and thus to add their strand voltage. Thus, between two bus bars 18 ', a greater voltage can be provided than can be generated by a single strand 1 1.

The busbars 18 'may each be connected in pairs to an output terminal 20, to each of which a device 100 may be connected. The connections of the bus bars 18 'to the individual electrical contacts of the output terminals 20 are shown in Fig. 1 by corresponding labels 1 +, 2+, 3+, 1 -, 2-, 3-, where "+" for positive potential and " - "can stand for negative potential or ground potential. The designations symbolize three possible pairs of busbars 1 +, 1 - and 2+, 2- and 3+, 3-, wherein the electrical contacts of the output terminals 20 alternately configured with different of the busbars 18 'connectable by another, not shown switching device could be. The output terminals 20 can always remain electrically isolated from each other, as long as each busbar 18 'of a terminal 20 is electrically connected to another strand 1 1. In this case, a simultaneous charging and discharging different strands 1 1 may be provided, for example, to supply a device 100 successively with electrical energy from different strands 1 1, which are recharged in between. For example, a charging of an electric vehicle (or generally a device) via a pair of busbars with an output voltage of 400V, for example, while charging other strands 1 1 eg via a transformer 21 at a charging voltage of eg 800 V from a supply network 22 or can be done from another device external energy source. The transformer 21 may be connected to an input terminal 23 of the energy supply device 10. If the strings 1 1 are not designed for this charging voltage, they can be connected in series to form a series circuit by means of the switching unit 15 '. The galvanic isolation is carried out by the use of different bus bars 18 'for the respective strands 1 1 and / or each voltage level (output voltage and charging voltage, eg 400V and 800V).

A power concentration can also be achieved by the strands 1 1, in that at the input connection 23 a power source, e.g. a solar system, with a first power feeds energy into at least one strand 1 1 and then the strand 1 1 this energy with a second power that is greater than the first power, to a device connected to an output terminal 20 device 100 again.

As a stationary storage device, the energy delivery device 10 can optionally have a modular AC / DC converter arrangement 24 with a plurality of AC / DC converters 24 'for the input connection 23, which can be individually switched between the busbars 18' by means of a switching unit 25, on a busbar 18 'to provide a predetermined current and / or charging voltage for a charging current or the respective AC / DC converters 24' galvanically separated from the busbar assembly 18 can. By means of further switching units 26, a galvanic isolation from the input terminal 23 is possible. The switching units 25, 26 may each be formed by a contactor. The switching units 25, 26 can be controlled by the switching device 19. By opening the two switching units 25, 26 of an AC / DC converter 24 ', this can thus be galvanically decoupled and also be replaced during operation of the energy delivery device 10. The switching units 25, 26 thus represent decoupling switches. The AC / DC converters 24 'can be designed to be galvanically isolating. However, the AC / DC converter arrangement 24 need not necessarily have galvanically isolating AC / DC converters 24 '. Other converters are cheaper. The galvanic isolation can be ensured at any time by means of the mechanical switches of the strings.

To the input terminal 23 instead of the supply network 22, a network-autonomous power source, such as an emergency generator or a wind turbine to be connected. On the other hand, the energy delivery device 10 itself can also have a network-forming effect, ie it can specify a network frequency with respect to other devices connected to the input connection. This is advantageous in particular for the use of the energy delivery device 10 in a region without its own supply network 22. It can AC devices without adaptation as on a public utility network operate. The opposite of the network-forming operation is the network-following operation, ie it is synchronized to a predetermined network frequency. For switching the switching units 15, 15 ', 25, 26 and the use units 12 and for receiving data from the use units 12, the control device 19 may be coupled to these components via a communication device 27. The communication device 27 may comprise, for example, a communication bus, for example a CAN bus (CAN - Controller Area Network), or an Ethernet.

The controller 19 thus generally accumulates knowledge of what can be switched as, e.g. which busbar 18 'on soft string 1 1 can be switched. The control device 19 may be at least partially ausgestaltest as a central control device for all strands 1 1 and / or at least partially as a distributed control device per strand 1 1. It may have a processor device with at least one microcontroller and / or at least one microprocessor. An operating program of the processor device can be set up to execute the described method steps for operating the energy delivery device 10 when executed by the processor device.

Optionally, capacitors 30, 31 (in particular double-layer capacitors) may be provided at the output terminals 20 and / or at the input terminal 23 in order to buffer load peaks. The utilization units 12 can thus be operated more gently at load peaks / peaks (in the range, for example, up to a duration of, for example, 3 s or 5 s), since the load peak is damped. A peak load may be an electrical power greater than a sum of the individual rated powers of the switched-on use units 12, in particular a power greater than 1, 2 times the sum.

For a switching operation on the bus bars 18 ', a recharging circuit or limiting circuit 32 (switch and resistive element) may be connected in series with the respective capacitor 30, 31 to conduct a capacitor current across the resistive element, limiting the current strength of the capacitor current to a predetermined maximum , The limiting circuit 32 can be used for charging and discharging the respective capacitor 30, 31. A capacitor 30, 31 with its limiting circuit 32 represents a capacitor device. The limiting circuit 32 thus represents a Vorladeschaltung.

Cooling of the strands 11 (in particular of the utilization units 12 in the strands 11) can be carried out, for example. be provided on a shelf by arranging a Kühlebene below the strand level.

Each bus bar 18 'may be made of aluminum or copper. Aluminum is the cheaper material and lighter than copper. Aluminum generates power losses (more than copper) through a specific resistance, from which heating power can be generated for a temperature control of the utilization units 12 (in particular battery cells), which are connected via a thermal coupling, e.g. a cooling circuit, can be transmitted from the busbars 18 'to the Nutzzeinheiten 12.

In a current distribution at several strands 1 1 on a power rail 18 'can be adjusted by setting / controlling the individual phase currents I via the DC-DC converter 14 of the strand 1 1, the current I, for. aligned or dynamically relocated. Thus, e.g. splitting the required total current for the device 100 into N strands 1 1, e.g. N = 3, and each string 1 1 generate a current I set especially for it, e.g. at N = 3: 50%, 25%, 25%.

As a result, the technology of the utilization units 12 available in the respective section 11 can be taken into account so that the utilization units 12 are operated within their specification. Since the electrical voltages U can be determined, the current I can then be set by means of the DC-DC converter 14, so that e.g. Balance currents flow between the strands 1 1, which are smaller than a threshold value. Thus, e.g. ensure that in the case of batteries per battery cell, a current I of up to 300-400 A flows only for 15 s, but a continuous current only up to 150 A. Each strand 1 1 can thus be operated with its own operating strategy, adapted to its technology. A suitable current intensity I can be set by means of the DC-DC converter 14.

Additionally or alternatively, depending on the line length 28 of the busbar sections, which lead from a strand 1 1 to an output terminal 20 (ie to a consumer), the current intensity I of the respective strand 1 1 by means of the DC voltage converter 14 through the Control device 19 can be adjusted to the division of the currents

Depending on the length of the line 28 and depending on the losses resulting therefrom, it is possible to set I in the case of several strings 1 1 connected in parallel so that the losses can be optimized (for example minimized or maximized for heating) and / or localized. A strand 1 1 with shorter line length 28 of the supply line over the busbars 18 'can be assigned to minimize a greater current I than a strand 1 1 with longer line length 28. Thus, the effect of different line lengths is compensated. The current intensity I can also be set as a function of a current temperature of the line sections. Such power management can compensate for the disadvantage of higher aluminum resistivity by setting and adjusting the current on individual line sections.

If required, by means of the control device 19, it is thus possible in summary to connect the strands 11 with the currently required property to the busbars 18 used which lead to the output connection 20, at which the power is picked up by a connected device 100. Each strand 1 1 can be coupled as needed by means of its switching units 15. Each strand 1 1 can be emptied / loaded individually. In addition or as an alternative, an efficiency optimization for the DC-DC converter 14 within the string 1 1 can be carried out by setting its input voltage by selecting and connecting useful units 12. The DC-DC converter 14 of each string

I I can thus fulfill two tasks. It limits the phase current I to a predefinable setpoint so that useful units 12 can be operated according to their specified specification (operating limits). The voltage U of the strand 1 1 can be adjusted to the busbar voltage. Thus, the equalizing currents between several strands 1 1 can be reduced. In addition, the DC-DC converter 14 ensures that a predetermined setpoint voltage is applied to the strand connections 17, regardless of the number of use units 12 actively operated in the strand 11.

A current measurement 16 for the phase current I can be done in the manner described centrally in the measuring unit 16 in the strand 1 1 and is anyway necessary for the regulation of the DC-DC converter 14. The central control device can also individually reconfigure this within each strand 1 1, ie, turn on and off useful units 12 in the series circuit 13 of the strand 1 1. If, for example, the strand voltage U is smaller than a required rail voltage of the switched-on conductor rails 18 ', more use units 12 can be connected in the series circuit 13 of the strand 11. This can be done so fast by means of semiconductor switches (eg transistors) that it can take place in a switching pause of the DC-DC converter 14. In FIG. 2 it is shown how each use unit 12 can be electrically bridged, electrically insulated and / or discharged by an individual switching device N10. For this purpose, semiconductor switches T (transistors) are provided in the said manner. Each use unit 12 may provide functions: a bridging / bridging circuit N1 1, a diagnosis unit N12, a (particularly passive) load balancing / discharging circuit N13, a decoupling / separating circuit N14. A semiconductor switch T must be able to block only a low-voltage, for example 2x single voltage V of the utility unit 12. The load balancing can also be active in a known manner (so-called active load balancing). In addition to the switch for the separation circuit N14, a further switch can also be provided for the second, opposite pole (all-pole switching). The diagnostic unit N12 can be designed in a known manner for a cell analysis, for example an impedance measurement by means of, for example, impedance spectroscopy. For this purpose, the diagnostic unit N12 can determine, per use unit 12 for an impedance spectral analysis (0 Hz to eg 3 kHz), a measuring current Γ and a single voltage V at several frequencies f, which results in the impedance curve over the frequency f. This represents an impedance spectrum. The diagnostic unit N12 can signal a current state value 29 of a measuring current Γ and / or the individual voltage V and / or the measured impedance via the communication device 27 to the control device 19. By the term "impedance" is meant in the context of the invention an impedance value at a predetermined frequency, eg 0Hz, or an impedance curve over the frequency f., Several frequencies can be checked in a frequency sweep with a stepwise increase or decrease A multi-frequency excitation can be provided at several frequencies at the same time.The multi-frequency excitation can be designed, for example, as a multisinus excitation or as a rectangular signal or as a jump signal. Each utilization unit 12 can thus be monitored individually, for example with regard to its SoH (state of health) and / or SoC (state of charge) and / or SoF (state of function). The parameters SoH and SoC and SoF are known per se from the prior art.

Irrespective of the impedance measurement, the individual voltage V of the utilization unit 12 can also be measured without the alternating voltage of the impedance measurement. A utilization unit 12 which is bridged (by means of the bypass circuit N1 1) can also be monitored with respect to its individual voltage V. Before connecting (closing N14 or switching electrically), the individual voltage V of the use unit 12 can be individually adjusted by means of the loadbalancing N13. Optionally, an electrical charging unit per use unit 12 can also be provided, which can individually charge the utility unit 12 even when the semiconductor switch of the disconnecting circuit N14 is open (each use unit 12 can thus be charged individually). The power supply of the charging unit may e.g. via the communication device 27 (for example by means of Power-over-Ethernet technology) or by means of a galvanically isolated power supply unit.

Mutual interlocking of N1 1 and N14 may be provided (e.g., software-related or by means of a logic circuit) so as not to create a short circuit. In addition, a temperature measurement by the diagnostic unit N12 or e.g. be provided by the controller 19, a conclusion on the temperature of the impedance.

The status of each use unit 12 can be read out and the switching unit N10 of each use unit 12 can be controlled, in particular the bridging circuit N1 1 in combination with the separation circuit N14. By combining switching of the bypass circuit N1 1 and the isolation circuit N14, a utilization unit 12 in the series circuit can be alternately connected and disconnected.

On this basis, the wear / state of each use unit 12 can be determined centrally in the control device 19 (for example in the form of the simulation). danz as wear value) and the switching state of each use unit 12 are set in dependence on the determined state. Individual power units 12 can be electrically removed from the string 1 1 (bridging N1 1), ingested (connected in series), individually discharged (discharge resistor R, balancing circuit N13), temporarily disconnected electrically (N14 open / electrically blocking) eg for the diagnostic unit N12.

Thus, it is possible to react to different wear / individual parameter dispersion of the utilization units 12 in the strand 11: Only use units 12 with similar parameter values are preferably actively operated. The similarity may be defined by a similarity criterion, e.g. specifies a maximum difference of at least one parameter, the difference in a range of 10% to 100% (twice / half) may be. An old / weak use unit 12 are first bypassed / switched out. This can be recognized by a performance criterion, e.g. refers to the impedance or is defined by the fact that the similarity criterion is violated. The performance criterion thus excludes weak usage units 12. The connection of old use units 12 / weak user unit 12 becomes possible again later, as soon as the conditions of the strand fit, that is to say the remaining use units 12 have likewise worn so far that the similarity criterion is fulfilled again.

The similarity criterion can reduce the need for load balancing. The power per unit of use (current I in the string is the same, but with different voltage results in a different performance, which results in a local heating and thus aging / wear) can be adjusted in advance. Because load balancing requires matching to the "weakest" unit of use, which produces the lowest voltage, ie it has to be reduced to the lowest voltage, by creating equal or similar operating conditions in advance using the similarity criterion, less balancing is required For example, if the individual voltages V = 4.1 volts and V = 3.9 volts are present in one string, balancing would have to be set to the weakest operating unit, ie 3.9 volts. are detected (performance criterion) and switched from the line 1 1 (Bridging N1 1) .The impedance is only one example of the detection of a weak use unit weakest use unit depending on a state of the use unit.

By electrical decoupling / separating N14 all use units 12 of a strand 1 1, the strand 1 1 can also be switched HV-free. All use units 12 are decoupled from each other. In this security mode, the strand 1 1 can be e.g. be secured for an assembly, an accident prevention, an emergency, a transport. The switching order is important: First, the mechanical switching units 15 (contactors) are opened, then the decoupling N14 of the utilization units 12 takes place in succession.

By the control device 19, a wear adjustment / wear leveling of the individual use units 12 can be provided. The wear leveling provides for the homogeneous use of the field / the arrangement of useful units 12. This results in a wear adjustment in the operation of the benefit units 12. Prototype can be the wear leveling from the FLASH memory technology (https://en.wikipedia.org/wiki/Wear_leveling).

The advantage of equalizing the wear is the extension of the overall life of the energy delivery device 10, since a probability of failure of individual use units 12, as can be caused by above-average wear of a single use unit 12, is reduced. The supply / removal of energy, i. the energy exchange E with a connected device 100, takes place by means of the next use units 12, which are according to wear leveling. For this purpose, a current state of wear is indicated as a wear value for each use unit 12. The aim of these measures is therefore a uniform wear. The wear value may e.g. be represented by the impedance of the use unit 12. The wear value indicates wear of the use unit 12.

For each use unit 12, depending on the wear value, a respective desired value at least one operating variable, for example the current I during discharging and / or the individual voltage V during charging, can be determined on the basis of a matching criterion, wherein the matching criterion provides that by setting each reference value one or some or all of the use units 12 in total complete the energy exchange E, but in this case a difference calculated from all the wear values the wear of the use units 12 is minimized. The wear of the use units 12 is thus adjusted during the energy exchange E by more heavily worn use units 12 are less burdened than less worn Nutzzeinheiten 12. The latter continue to use, thereby equalizing their wear state of the less burdened Nutzzeinheiten 12.

The wear value changes during operation, and more quickly if the utilization unit 12 is operated at an operating point which deviates from an ideal state (the utilization unit continues to wear out). Therefore, even measures are useful.

For this purpose, the utilization units 12 are preferably operated only within a tolerance interval around an ideal charging state, which is e.g. may be at a state of charge of 50%, and / or may specify a current profile of an electric current flowing during the energy exchange of the use unit 12.

In general, the ideal state depends on the used technology of the user unit and is known in the prior art. The ideal state for battery modules can be defined by the following parameters:

SoC - State of charge (energy content) - ideal are e.g. 50%;

DoD - Depth of Discharge - Degree of discharge (current profile) e.g. ideal state of charge 50% minus maximum 20% (tolerance interval).

The specified ideal values depend on the electrochemistry and / or the intended application and must be determined by a person skilled in the art in each case for the specific energy delivery device.

In general, the DoD should remain "small", ie not sink too far down The further the current operating point is away from the ideal state, the faster the wear value increases The current operating point can be adjusted by the charging current / discharge current I for the utilization units 12 The AC / DC converter arrangement 24 can be used for adjusting the charging current, the DC-DC converter 14 for setting the discharge current, while the wear conditions / wear values of all the utilization units are to be adjusted.

Another precautionary measure is the following: An overcapacity of use units 12 can be maintained. Without additional switch can be distributed by means of an overcapacity of Nutzzeinheiten 12 the burden. This results in a lower load per use unit 12, in that all use units will always be used in order to wear evenly. In addition, the service life is prolonged because of the lower load; because if, for example, per strand at 1 10% capacity (sum of the individual capacities of the use units 12 in the strand) with throttling by the control device 19 only 100% (nominal nominal value) are retrieved, results in a lower peak load per use unit 12. The strand 1 1 delivers For example, a larger voltage than needed, so less current I must flow for the same power as with a population of only 100% nominal value (rated capacity). For example: 12 user units are provided, but a nominal of only 10 user units is nominally made available. Without a switch, 12 user units must be switched on, but only the capacity can be retrieved electronically for only 10 user units (no switching required!). As a result, even weaker use units are possible, since their peak currents are lower, and because of the resulting higher strand voltage U, as more Nutzzeinheiten connected in series than nominally available. The use of cheaper units possible.

If switches are available, e.g. the semiconductor switches T, a switching between the use of units 12 of a strand 1 1 may be provided, e.g. There are always 10 usage units provided (gives the nominal capacity) and 2 usage units bridged.

The provision of an overcapacity of utilization units 12 means that the sum of the individual nominal capacities of the utilization units 12 (ie their combined gross capacity) is greater than the nominal capacity made available to the outside. As a result, a failure of a use unit can be compensated. For example, the energy delivery device 10 may be provided as an energy storage (eg, battery storage) having a designated or nominal rated capacity (eg, 100 kWh). In fact, internally a gross capacity is provided which is greater than the nominal capacity made available from the outside (actual gross capacity of eg 1 10kWh, greater than the net capacity of eg 100kWh). In other words, more use units (eg, battery cell modules) are available than are needed to provide the nominal capacity. For example, only so many use units are made available for unloading to the outside, as corresponds to the nominal capacity. These payload units are then active units or "active units." The remaining (non-actively used) storage units are "reserve units".

Bad block management (BBM - Bad Block Management) detects or decommissioned defective units. That in case of failure / failure of an active unit (defective use unit), this failed active unit out of service and a reserve unit (previously inactive use unit) can be put into operation as a new active unit. Thus, despite the failure of one or more units, the nominal nominal capacity remains. The term bad block management (BBM) comes from the flash memory technology (https://en.wikipedia.Org/wiki/Flash_memory#Memory_wear).

However, in normal operation, rotating or switching (for example according to the round-robin algorithm or generally a predetermined replacement rule) between the utilization units can also be carried out in order to uniformly wear all the utilization units. If a spare unit is then activated as a replacement for a failed active unit, then the reserve unit already has similar electrical properties to the other active units because it already has a similar degree of wear (in the sense of the mentioned similarity criterion). This can reduce the degree of load balancing required in the manner described.

Due to the division of user units into active units and reserve units, servicing units can also be replaced during operation of the energy store without impairing the rated capacity. Replacement units can be separated / taken out of service and then removed / replaced (dynamic change of the units) as a reserve unit.

The bath block management and / or the replacement can also be done groupwise or strand-wise, ie it is then switched a group of benefit units 12 or the entire series circuit 13 of a strand and / or replaced. Even within a use unit 12, a bath block management can take place. Thus, for example, a battery unit configured as a use unit 12 may be provided a plurality of battery cells, eg 12 battery cells as a 3-fold series connection of 4 battery cell len in parallel connection. It can then be switched out in each case a parallel connection, eg by bridging.

The following can be provided for a load management for the strands.

Via the busbars 18 can be interconnected by means of the DC-DC converter 14 to transfer energy. A strand 11 can thus be charged via several sources, e.g. 40kW from other string 1 1 and 10kW from a grid AC / DC converter 24 'to provide 50kW charging power.

In the power output, a load profile can be smoothed / smoothed by e.g. some strands 1 1 provide the consumer, while other strands 1 1 already charging, and then stand by for further charging. For example, can simultaneously charge with e.g. 10A and unloading with e.g. 20A take place (at least one strand 1 1 loads the device 100, at least one other strand 1 1 is charged from the supply network 22). It is also possible to generate a boost current (short-term peak, for example more than a factor of 1.5) by connecting a string 1 1.

The (thermal / electrical) loading of the individual strands 11 can be limited by alternately supplying different strands 11 to a connected device 100 (e.g., charging an electric vehicle). Thus, the said DoD (Depth of Discharge) can also be limited, e.g. to 20%.

By means of the mechanical switching units 15 on each strand 1 1 can also be a complete galvanic isolation between the strands, if they are connected to different busbars. This is the prerequisite for being able to charge multiple devices 100 (e.g., e-vehicles) at the same time. Each e-vehicle is connected to another busbar 18 'which is galvanically isolated from the remaining busbars. Overall, the example shows how the invention can provide bath block management in an electrical power delivery device

Claims

CLAIMS:

An electrical energy delivery device (10) having a respective nominal nominal capacitance of at least one predetermined electrical characteristic, the respective rated capacitance being provided by a plurality of utilization units (12) each having a respective single nominal capacitance with respect to the respective characteristic, and wherein a control means (19) thereto is arranged to control an energy exchange (E) between the energy delivery device (10) and at least one device external device (100),

characterized in that

in each case the sum of the respective individual nominal capacities of the utilization units (12) is greater than the respective nominal nominal capacity of the at least one characteristic variable and the control device (19) is adapted to limit the respective characteristic variable to the respective nominal nominal capacity in the energy exchange (E).

The energy delivery device (10) of claim 1, wherein the at least one characteristic comprises the electrical storage capacity and / or the maximum electrical power and / or the maximum electrical current.

Energy delivery device (10) according to any one of the preceding claims, wherein each use unit (12) each at least one battery cell, in particular a battery cell module or a composite of several battery cell modules, and / or at least one fuel cell and / or at least one solar panel and / or at least one capacitor and / / or includes a generator.

Energy delivery device (10) according to any one of the preceding claims, wherein the control device (19) is adapted for the energy exchange (E) more use units (12) to electrically connect to the at least one device (100), as to provide the respective nominal capacity of at least one characteristic is necessary, and / or wherein

the control device (19) is adapted to operate the energy delivery device (10) for a predetermined period of time with its gross capacity representing the sum of the individual nominal capacities. Energy delivery device (10) according to any one of the preceding claims, wherein the control device (19) is adapted, in each case only a few of the use units (12) with the at least one device (100) connected to the energy exchange device (10) in the case of several energy exchange processes carried out one after the other. electrically connect and for each of the energy exchange operations to select the respective use units (12) to be connected in accordance with a predetermined replacement rule. Energy delivery device (10) according to any one of the preceding claims, wherein the control device (19) is adapted to determine a respective wear value of each use unit (12) and one of the use units (12) whose wear value meets a predetermined wear criterion, by electrical disconnection to take out of service.

Energy delivery device (10) according to claim 6, wherein the control device (19) is adapted to at least put a decommissioned use unit (12) back into operation by electrical coupling, if their wear value in comparison with the respective wear value of the already in operation Use units (12) fulfills a predetermined similarity criterion.

An energy delivery device (12) according to any one of the preceding claims, wherein the control means (19) is adapted to detect a defective utility unit (12) and electrically disconnect it from the remaining utility units and during operation of the energy delivery device (12) after replacement of the defective utility unit (12) by a new utility unit to electrically couple the new utility unit with the other Nutzzeinheiten.

Energy delivery device (10) according to any one of the preceding claims, wherein each of the Nutzzeinheiten (12) to a respective strand (1 1) are connected to a series circuit (13) and each strand (1 1) via a DC-DC converter (14) and at least one galvanically separable switching unit (15) with a busbar assembly (18) of the energy delivery device (10) is connected and within each strand (1 1) for each use unit (1 1) a bypass circuit (N1 1) is provided and the energy delivery device (10) carries out the energy exchange (E) via the busbar arrangement (18) and the control device (19) is arranged to limit the at least one characteristic, the DC-DC converter (14) and the at least one switching unit (15) and the bypass circuits ( N1 1) of each strand (1 1).

A method of providing a respective nominal rated capacity of at least one predetermined electrical characteristic in an electrical power delivery device (10), the respective nominal capacity being provided by a plurality of payload units, each having a respective single nominal capacity relating to the respective characteristic, and wherein a control means (19 ) controls an energy exchange (E) between the energy delivery device (10) and at least one device external device (100),

characterized in that

in each case the sum of the respective individual nominal capacities of the utilization units (12) is greater than the respective nominal nominal capacity of the at least one characteristic variable and the control device (19) limits the respective characteristic variable to the respective nominal nominal capacity during the energy exchange (E).