Arrangement and method for transferring electrical energy from a source to a sink through a slot-like feedthrough

Abstract

An arrangement for transmitting electrical energy from a source (14), preferably a photovoltaic system, to a sink (15) through a slot-like opening (9), preferably a window gap, is disclosed. The arrangement comprises at least a first connection unit (2), a second connection unit (3), and a feedthrough cable (4) connecting the first and second connection units (2, 3). The feedthrough cable (4) is designed to pass through the opening (9) and has at least one power line (7) and at least one detection line (8). The at least one power line (7) is designed to transmit electrical energy from the source (14) to the sink (15). The at least one detection line (8) is connected to the at least one power line (7) in the second connection unit (3).Furthermore, the first connection unit (2) has a detection unit (16) which is connected to the at least one detection line (8) and the at least one power line (7). The detection unit (16) is configured to detect a potential difference between the at least one power line (7) and the at least one detection line (8) and, if a predefined limit value is exceeded by the potential difference, to generate and output a trigger signal (17). Furthermore, a corresponding procedure has been disclosed.

Description

[0001] The invention relates to an arrangement and a method for transmitting electrical energy from a source, preferably a photovoltaic system, to a sink through a slot-like passage, preferably a window gap.

[0002] When electrical energy is to be transmitted from a source to a sink, it is not uncommon for power lines to be routed through a wall. This may be necessary, for example, if the source is located outside a building and the sink is inside. Typically, a hole is drilled through the wall to route the power line through it. However, in some cases, drilling through a wall is not permitted. Such situations can arise, for example, when installing so-called balcony photovoltaic systems (also known as balcony power plants).

[0003] Balcony photovoltaic systems are smaller systems for generating electrical energy from solar power, usually comprising one or a few photovoltaic modules. Their name derives from the fact that they can be mounted on balcony railings or parapets. In Germany, balcony photovoltaic systems with a nominal electrical output of up to 600 watts (and up to 800 watts from 2024) can currently be installed without any bureaucratic hassle. This is intended to help tenants, for example, generate electrical energy and thus contribute to a transition toward renewable energy.

[0004] The energy generated by the balcony photovoltaic system is typically converted into alternating current using an inverter and fed into the power grid. This generally requires that the balcony has a grid connection through which the generated electrical energy can be fed into the grid. If such a grid connection is not available and drilling through the wall is not possible, window feedthroughs are an alternative. These allow the solar-generated direct current to be routed from the balcony into the apartment, fed into the apartment's inverter, and then fed into the energy grid within the apartment. For this purpose, thin, insulated electrical conductors are placed in the gap between the window and the frame.

[0005] The disadvantage of this solution is that the electrical conductors in the window gap are subjected to considerable stress. When the window is closed, the seals and window profiles act on the electrical conductors. This deforms the conductors guided through the window gap at gaps and overhangs with a more or less small bending radius. When the window is opened and closed, there is an alternation between different stresses. In addition, moving window parts can damage the insulation. This can damage the conductors as a whole. High currents usually flow through the conductors; with a photovoltaic system with a rated output of 600 watts, this is not uncommon for up to 20 amps. These currents can heat a damaged conductor to such an extent that the window frame is seriously damaged or even ignited. Regular inspections of the window penetrations are therefore essential.Since the stress on window penetrations depends significantly on the installation situation, determining maintenance intervals is difficult and rarely meets the requirements in practice. As a result, too many inspections tend to be required.

[0006] The invention is based on the object of providing an arrangement and a method for transmitting electrical energy through a slot-like feedthrough, for example, a window gap, that enables reliable operation without the need for frequent maintenance. It is helpful if the arrangement is easy to install and has a cost-effective design.

[0007] This problem is solved by the feature combinations of the independent claims. Further embodiments are disclosed in the respective subclaims.

[0008] It should be noted that the features listed individually in the claims can be combined with one another in any technically reasonable manner (even across category boundaries, for example, between methods and devices) and demonstrate further embodiments. The description further characterizes and specifies the invention, particularly in conjunction with the figures.

[0009] It should also be noted that a conjunction “and / or” used herein between two features and linking them together is always to be interpreted in such a way that in a first embodiment only the first feature can be present, in a second embodiment only the second feature can be present and in a third embodiment both the first and the second feature can be present.

[0010] For cables used to transmit electrical energy through a slot-like feedthrough, damage that is not readily visible from the outside is particularly critical. If the insulation of a cable is damaged due to continuous mechanical stress, this can be easily detected even by a person without special prior knowledge and without technical tools. If conductors break within the cable, for example, individual conductors in a stranded wire, this damage is usually not detectable without a measuring instrument. Detecting this type of damage is therefore particularly important.

[0011] Damage within a feedthrough cable is typically accompanied by an increase in internal resistance. During operation, a voltage drop across such damaged feedthrough cables exceeds the voltage drop across an undamaged cable. This increased voltage drop leads to increased heating of the feedthrough cable, which can ultimately cause damage to the environment surrounding the feedthrough cable, such as the feedthrough surrounding the feedthrough cable or the objects bordering a feedthrough. The present disclosure is based on detecting excessive voltage drops across the feedthrough cable.

[0012] In practice, it is not possible to simply connect a voltage measuring device to the feedthrough cable to measure the voltage drop across the feedthrough cable. Therefore, the present disclosure utilizes a feedthrough cable that, in addition to at least one power line, additionally has at least one detection line. This at least one detection line can be used to detect the voltage drop across the feedthrough cable.

[0013] The present disclosure utilizes a first connection unit and a second connection unit connected by the feedthrough cable. In an installation situation, the first connection unit may be located on one side of a feedthrough and the second connection unit on the other side of the feedthrough, while the feedthrough cable is routed through the feedthrough. If one of the two connection units is connected to the source and the other of the two connection units is connected to the sink, electrical energy can be transmitted via the at least one power line of the feedthrough cable. In the case of a balcony photovoltaic system as the source, for example, the first connection unit may be located on the outside, the second connection unit inside the apartment, and the feedthrough cable in a window gap of a window between the outside and the apartment.In this way, the electrical energy generated by the balcony photovoltaic system can be transmitted into the apartment via the first connection unit, the feed-through cable and the second connection unit.

[0014] It should be noted that the arrangement disclosed here does not necessarily have to have only a first connection unit and / or only a second connection unit. Rather, the arrangement can also have multiple first connection units and / or multiple second connection units. Additional connection units allow the connection of further sources or sinks. The multiple connection units can share parts of the arrangement, for example, lines of the feed-through cable. Without limiting generality, the singular is generally used here when reference is made to the first or second connection unit.

[0015] The first connection unit further comprises a detection unit, which is connected on the one hand to the detection line and on the other hand to the power line. This connection is preferably made within the first connection unit. If there are multiple power lines and / or multiple detection lines, multiple power lines or multiple detection lines can be connected to the detection unit; the following explanations then apply accordingly. The side of the detection line facing away from the detection unit is connected to the power line in the second connection unit. Since a significantly higher current is likely to flow through a power line than through a detection line, a potential is present on the side of the detection line facing the detection unit, which can approximately correspond to the potential at the power line in the second connection unit.The detection unit can measure the potential of the connected power line and the potential of the connected detection line and / or a potential difference between the detection line and the power line, and use this to determine a voltage drop across the power line. This voltage drop provides an indication of the internal resistance of the power line and any contact points present, and thus an indication of any damage to the power line and the contact points. Therefore, the determined potential difference is compared with a predefined limit. If the potential difference exceeds the predefined limit, damage to the feed-through cable can be inferred, for example, due to a break in one or more of the at least one power line or a plurality of strands of a power line. The detection of damage can be signaled with a trigger signal.The trigger signal can be used within the first connection unit, output from the first connection unit, signalled by illuminated and / or acoustic signals and / or output and / or used in any other way.

[0016] It is also conceivable that a detection line is damaged. Since the connection to the power line on the second connection unit side is no longer present or significantly reduced, the detection unit will detect a large potential difference and generate and output a trigger signal. Even in this fault scenario, safe continued operation of the system is no longer guaranteed, so generating a trigger signal is appropriate and / or sensible.

[0017] The voltage drop across the at least one power line does not only depend on the internal resistance of the at least one power line. Rather, the flowing current also influences the voltage drop. In one embodiment, it is not taken into account whether the increased voltage drop results from the internal resistance or the flowing current. Even if the internal resistance is not yet critically high, an excessively high current can lead to damage, so the cause of the increased voltage drop can be regarded as insignificant. In another embodiment, in addition to the voltage drop across the at least one power line, the flowing current or a variable representative of the flowing current can be taken into account. The flowing current can be used to generate the trigger signal. For example, the flowing current could be used to scale the limit value.

[0018] The arrangement disclosed here can have multiple power lines and multiple detection lines. The multiple power lines can be used in different ways. In principle, a mechanism could be implemented with which the power lines are switched on as needed. In one embodiment, the multiple power lines or a subset of the multiple power lines are connected in parallel. If there are multiple detection lines, these can also be connected in parallel, so that if one detection line fails, at least one other is still functional. However, it is also conceivable for the multiple detection lines to be used for a subset of multiple power lines, and for each of the subsets to be separately detected, the voltage drop across one of the multiple detection lines.

[0019] The "first connection unit" and the "second connection unit" can be configured differently. The only important thing is that they are arranged on each side of the feedthrough cable and have or can establish a connection to the source or sink. How these requirements are met and how the connection units are constructed is not critical to the present disclosure.

[0020] It should also be noted that the terms "first connection unit" and "second connection unit" are chosen merely to distinguish between the two connection units. This does not necessarily indicate which of the connection units is connected to the source and which to the sink. In one embodiment, the connection units are constructed symmetrically, so that a connection unit can be connected either to the source or the sink. Without limiting generality, however, it is assumed below that the first connection unit is designed to connect to the source and the second connection unit to connect to the sink.

[0021] The "source" can also take various forms. The key factor is that the source emits electrical energy, and this emitted electrical energy is to be transferred to a sink. How this electrical energy is generated and whether it is output as direct or alternating current is not important. However, the source is preferably a photovoltaic system, particularly preferably a balcony photovoltaic system. This means that the emitted energy is preferably transferred using direct current.

[0022] Accordingly, the "sink" can also be designed in various ways. It is advantageous that the sink can absorb the energy transmitted from the source. How specifically and reliably this happens is not crucial. For example, it is conceivable that the sink is an energy storage device in which the transmitted energy is stored. The sink can also be an electrical device that uses the transmitted energy for its operation. The sink can also be an inverter that converts the transmitted energy into alternating current and feeds it, for example, into a power grid. It is also conceivable that multiple sinks absorb the transmitted energy.

[0023] The “slot-like feedthrough” can also take on a variety of forms. “Slot-like” means that the cross-section of the feedthrough is significantly larger in one direction than in another. This can mean that the feedthrough is significantly wider than it is thick. In one embodiment, the feedthrough is less than 3 millimeters thick, in another embodiment less than 1 millimeter, in a further embodiment less than 0.5 millimeters. In one embodiment, the feedthrough is at least 5 millimeters wide, in another embodiment at least 50 millimeters, in a still further embodiment at least 100 millimeters. A preferred embodiment of a slot-like feedthrough is a window gap, i.e. the space that is formed between a window sash and the associated window frame when closed. This window gap is usually sealed with one or more rubber seals.

[0024] The "feed-through cable" is designed to pass through this slot-like feed-through. This usually means that the feed-through cable is adapted to the expected feed-through. The feed-through cable will therefore usually have a significantly greater extension in a first transverse direction than in a second transverse direction perpendicular to the first transverse direction. This can mean that the feed-through cable is flat and the lines extend in its longitudinal direction. Flat can mean in one embodiment that the cable is at least 10 millimeters wide in the first transverse direction, in another embodiment at least 50 millimeters and in a further embodiment at least 100 millimeters. In the second transverse direction the feed-through cable can be less than 3 millimeters thick in one embodiment, less than 1 millimeter thick in another embodiment and less than 0.5 millimeters thick in a further embodiment.Of course, there are limits to both width and thickness. Feed-through cables with a width of 300 millimeters and a thickness of 10 micrometers may no longer be practical, to name just one example of a very wide and very thin feed-through cable.

[0025] The “at least one power line” should be designed to transmit the energy to be transmitted. This means that the power line(s) will be adapted to the energy to be transmitted. This applies in particular to the ability to conduct the energy, but also to the insulation of the conductors against contact and distances. The at least one power line can be formed by a single conductor that is, for example, flat and wide. However, the at least one power line can also be formed by several parallel conductors that are connected, for example, at their ends. The at least one power line can each be formed as a solid conductor or stranded wire made up of a plurality of individual conductors. These few examples, which are not to be understood as limiting, show how universally the at least one power line can be formed.

[0026] The "at least one detection line" can also be designed differently. The at least one detection line can be designed similarly to one of the at least one power lines. Since large currents will not typically flow through the at least one detection line, the at least one detection line can be designed relatively thin. It is important that the at least one detection line—similar to the at least one power line—withstands the mechanical stress in the slot-like feedthrough for at least a certain operating time, for example, one or several years. However, this requirement can usually be met without any problems.

[0027] As already mentioned, the detection unit should be capable of detecting a "potential difference" between the detection line and the power line and comparing it with a predefined limit value. How this is done specifically is not critical. In one embodiment, the detection unit detects a first potential at the detection line and a second potential at the power line and determines the potential difference by calculating the difference between the first potential and the second potential. In another embodiment, the detection unit detects the potential difference directly, without individually detecting the respective potentials at the detection line and the power line. Both embodiments are usable in principle within the meaning of the present disclosure.

[0028] The "predefined limit" can define which voltage drop across the feedthrough cable is non-critical and above which excessive heating of the feedthrough cable is to be expected. The limit depends on various conditions, such as the expected current, the installation environment, the transmitted power, the heat dissipation capability, the temperature resistance of the material surrounding the feedthrough, and the like. Overall, by setting the limit, it can be defined which voltage drop is still considered non-critical. This also allows a balance to be struck between premature shutdown and the risk of excessive heating. It is important that reliable yet safe operation of the arrangement can be achieved.

[0029] The arrangement disclosed here can be implemented in different ways. In one embodiment, the arrangement is constructed exclusively using hardware. The detection unit and the comparison with a threshold value can be implemented, for example, using an operational amplifier. In another embodiment, the arrangement is expanded using a combination of hardware and software. For example, the detection unit can be implemented in a microprocessor with corresponding program code.

[0030] The following explanations largely refer to one power line or one detection line. This does not necessarily mean that only one power line and / or only one detection line must be used. Rather, multiple power lines can also be used. The multiple power lines can be the at least one power line or a subset of the at least one power line. The same applies in principle to the detection line.

[0031] In one embodiment, the first connection unit has an analog-to-digital converter for generating a digital value, wherein the digital value is representative of a potential at the power line and / or a potential at the detection line and / or a potential difference between the power line and the detection line. In this way, the detection unit can be implemented in a processor and the potential difference can be digitally evaluated. In principle, an analog-to-digital converter of a microcontroller or the like could be used for this purpose. Preferably, however, a separate analog-to-digital converter is used. In this way, a better resolution of the potential difference can be achieved, since the potential difference is likely to be quite small compared to the voltage at the power line.In typical application scenarios, the potential difference will be in the range of a few volts or below one volt, sometimes even in the millivolt range, while the voltage on the power line is likely to be in the range of several tens of volts, sometimes even in the three-digit volt range.

[0032] In a further development, a voltage reducer is arranged between the analog-to-digital converter and the power line and / or between the analog-to-digital converter and the detection line. This voltage reducer reduces a detected potential by a defined ratio or by a defined amount. A voltage reducer can reduce the absolute value of the detected voltage. In a particularly simple embodiment, this can be achieved using a voltage divider. Reducing the voltage by a defined amount, for example, using a Zener diode, reduces the absolute value but leaves the potential difference at its full value. This allows the digital value to be reproduced with better resolution.

[0033] In one embodiment, the first connection unit is designed such that a negligible current flows through the detection line relative to the current flowing through the power line. Ideally, a current close to 0 amperes flows. In this way, the voltage drop across the detection line can be neglected. This can be achieved by connecting the detection line to the first connection unit with a high impedance.

[0034] In one embodiment, the first connection unit comprises a switching device that enables a current flow through the feed-through cable during normal operation and interrupts the current flow in a disconnected state. In this way, the current flow through the arrangement can be influenced. In one embodiment, the switching device is formed by a relay. In another embodiment, the switching device is formed by an electronic switch, for example, a MOSFET.

[0035] In a further development, the switching device is communicatively connected to the detection unit and configured to receive the trigger signal. Upon receipt of the trigger signal, the switching device switches from normal operation to the disconnected state. In this way, upon detecting a faulty feedthrough cable or other fault condition, the detection unit can prevent the transmission of energy from the source to the sink and establish a safe state.

[0036] In one embodiment, the arrangement can have a thermal fuse that monitors the temperature of at least part of the arrangement and interrupts the flow of current through the feed-through cable if a predefined temperature limit is exceeded or reached. This allows further protection of the arrangement. A temperature sensor of the thermal fuse can be integrated into the feed-through cable or attached to the feed-through cable. Since the conductors of the feed-through cable are usually also good temperature conductors, the temperature sensor can also be integrated into the first and / or second connection unit, for example on the circuit board of the respective connection unit and / or a few millimeters away from the connection between the circuit board and the feed-through cable. The previously mentioned switching device can be used to interrupt the flow of current.

[0037] In one embodiment, the feed-through cable is formed by a flexible printed circuit board, wherein a plurality of longitudinally running conductor tracks are arranged on the flexible printed circuit board, wherein at least one of the plurality of conductor tracks forms the at least one detection line and at least one of the plurality of conductor tracks forms the at least one power line. Flexible printed circuit boards offer the advantage that they can be designed to be very thin and flexible. Flexible printed circuit boards consist of a carrier material onto which a copper surface is laminated. Typical flexible printed circuit boards consist of 35 micrometers of copper and 43 micrometers thick plastic layers below and above the copper. This means that flexible printed circuit boards can have a thickness of just over a tenth of a millimeter. Typical dielectric strengths are 300 Vrms. On such feed-through cables, the power line can be designed as a very wide copper line.Nevertheless, damage to the feedthrough cable leads to a detectable increase in the voltage drop.

[0038] In one embodiment, the feed-through cable is formed by a ribbon cable with several individual conductors, wherein at least one of the several individual conductors forms the at least one detection line and at least one of the several individual conductors forms the at least one power line. Ribbon cables are well known in practice. They have been used in computers for many years to connect hard drives and other devices, so that very robust and durable ribbon cables are available. Typical dielectric strengths are 300 Vrms. With a typical material thickness of 1 millimeter (including insulation), ribbon cables are still quite thin. Typically, one conductor of a ribbon cable can conduct a current of 1 ampere, so that currents of 20 amperes are also easily manageable. In this context, a single conductor is understood to be a cable structure that is insulated from other single conductors. In many cases, a single conductor is represented by a stranded wire, i.e.a composite of several very thin individual wires.

[0039] In one embodiment, the arrangement comprises a feed-through cable for a forward line and a feed-through cable for a return line, wherein the feed-through cable for the forward line and the feed-through cable for the return line are preferably designed separately from one another. Separate forward and return lines can achieve reliable and safe power transmission. By designing the forward and return lines separately, the dielectric strength between the forward and return lines can be increased and heat dissipation can be better distributed.

[0040] In one embodiment in which the feed-through cable has a plurality of power lines, the plurality of power lines can be connected in parallel, wherein the ends of the plurality of power lines on the first connection unit side and / or on the second connection unit side are each preferably connected together at a connection point of the feed-through cable with the respective connection unit. By connecting a plurality of power lines in parallel, the transmission performance can be improved. At the same time, energy can still be transmitted reliably if one or more power lines fail. By connecting them together directly at the connection point of the feed-through cable, material can be saved, for example space on the circuit board of the respective connection unit.

[0041] In one embodiment, the feed-through cable is detachably connected to the first connection unit and / or the second connection unit. A detachable design allows for more cost-effective and sustainable operation. This is because, in the event of a defective feed-through cable, the connection units can usually continue to be used after the feed-through cable has been replaced. Furthermore, detachability can simplify the installation of the assembly.

[0042] In one embodiment, the first connection unit and the second connection unit each have a connection connector for connecting to the source and / or the sink, wherein the connector is preferably a multi-pin connector. In this way, the source and sink can be flexibly connected to the connection units. Multi-pin connectors allow for simplified connection because the number of connectors is reduced.

[0043] In a further development, the connector is an MC4-compatible or MC4 Evo2-compatible connector. MC4 and MC4 Evo2 are widely used connectors for photovoltaic systems.

[0044] In one embodiment, the feedthrough cable has a maximum length of one meter, preferably a maximum of 50 centimeters, and particularly preferably a maximum of 30 centimeters. A maximum length of one meter covers most expected installation scenarios. A maximum length of 50 centimeters offers lower material requirements while allowing for universal use. A maximum length of 30 centimeters allows for the implementation of common window feedthroughs while simultaneously avoiding unnecessary cable lengths.

[0045] In one embodiment, the arrangement offers a transmission power of up to 300 watts, preferably up to 600 watts, particularly preferably up to 800 watts, and even more preferably up to 1000 watts. A transmission power of 300 watts allows for the connection of smaller photovoltaic systems. A transmission power of up to 600 watts can connect currently common balcony photovoltaic systems. A transmission power of up to 800 watts can also connect larger balcony photovoltaic systems. A transmission power of up to 1000 watts provides reserves for further power increases.

[0046] In one embodiment, the feed-through cable has at least one bending-resistant insert, wherein the at least one bending-resistant insert is arranged parallel to the at least one power line and / or the at least one detection line and is designed to limit a bending radius of the feed-through cable to a minimum bending radius. In this way, the risk of damage to the conductors and / or crushing of the conductors can be further reduced. The bending-resistant insert can be formed from a material that is thicker and / or more rigid than the power line(s) and / or the detection line(s). The bending-resistant insert can be made, for example, from a plastic, steel, or spring steel, to name just a few possible materials. The bending-resistant insert can be formed in one piece. However, it is also conceivable for the bending-resistant insert to consist of several sections.The sections can be arranged so close to one another that, upon reaching a defined minimum bending radius, the sections touch and mutually block each other, making a smaller bending radius impossible. In a further development, such bend-resistant inserts are arranged on both sides of the feed-through cable. In a further development, bend-resistant inserts are additionally or alternatively embedded between lines of the feed-through cable in the feed-through cable. In principle, the at least one bend-resistant insert can also be used to maintain the dimensional stability of the feed-through cable in the feed-through. In this way, regular mechanical bending of the feed-through cable, for example, in a window gap, can be reduced or completely avoided.

[0047] Further features and advantages of the invention will become apparent from the following description of non-limiting embodiments of the present disclosure, which are explained in more detail below with reference to the drawings. In this drawing, schematically show: Fig. 1 is a block diagram of an embodiment of an arrangement according to the present disclosure, Fig. 2 is a circuit diagram of an implementation of an embodiment of an arrangement according to the present disclosure and Fig. 3 is a flowchart of an embodiment of a method according to the present disclosure.

[0048] In the different figures, parts that are equivalent in terms of their function are always provided with the same reference symbols, so that they are usually only described once.

[0049] Fig. Figure 1 shows a block diagram with functional blocks of an embodiment of an arrangement according to the present disclosure. The arrangement 1 comprises a first connection unit 2, a second connection unit 3, and a feed-through cable 4 connecting the first and second connection units 2, 3. The feed-through cable 4 is detachably connected to the first connection unit 2 via a first feed-through connector 5 and, on the opposite side, to the second connection unit 3 via a second feed-through connector 6. In principle, only one side could be detachably designed.

[0050] The feedthrough cable 4 comprises N power lines 7 and M detection lines 8, where N and M are each natural numbers. N can be in the single-digit to mid-double-digit range. M should usually be in the single-digit range. The feedthrough cable 4 is routed through a feedthrough 9, which is Fig. 1 is merely indicated and with which an exterior space 10 can be connected from an interior space 11. The feedthrough 9 can, for example, be a window gap. In principle, it is also conceivable that N / 2 of the power lines 7 are used for a forward line and N / 2 for a return line. The same applies to the M detection lines 8.

[0051] The first connection unit 2 has a first connector 12, and the second connection unit 4 has a second connector 13. In the illustrated embodiment, the first connector 12 is designed for connection to a source 14, here a balcony photovoltaic system, and the second connector 13 is designed for connection to a sink 15, here an inverter with a connected energy supply network. The first and second connectors 12, 13 can be designed as MC4 Evo2 connectors.

[0052] The first connection unit 2 further comprises a detection unit 16, which is connected to the at least one power line 7 and the at least one detection line 8. The detection unit 16 comprises an output for outputting a trigger signal 17. A switching device 18 is arranged in the line between the first feedthrough connector 5 and the first connection connector 12. In the conductive state, this switching device 18 connects the at least one power line 7 to the first connection connector 12. When the switching device 18 receives a trigger signal 18, the switching device 18 opens, and the connection is broken.

[0053] In the second connection unit 3, the at least one detection line 8 is connected to the power line 7. As a result, the detection unit receives, on the one hand, the potential of one side of the power line 7 (the side facing the first connection unit 2) and, on the other hand, the potential of the other side of the power line 7 (the side facing the second connection unit 3) via the detection line 8.

[0054] Fig. 2 shows a circuit diagram of an implementation of an embodiment of an arrangement according to the present disclosure. A first connection unit 2 is connected to a second connection unit 3 by a feed-through cable 4. In this case, one feed-through cable 4 is provided for the forward line 19 (+ pole) and an identical feed-through cable 4 for the return line 20 (- pole). The source 14 is formed by a balcony photovoltaic module, and the sink 15 by an inverter with a connected power supply network. The feed-through cable 4 is formed by a flexible circuit board or a ribbon cable with a total of 30 conductor tracks or individual conductors. Each of the conductor tracks or individual conductors has an internal resistance, which is indicated by a resistance symbol. 29 of the conductor tracks / individual conductors form power lines 7, and one of the conductor tracks / individual conductors forms the detection line 8.The feedthrough cable 4 is connected to the first and second connection units 2, 3 via first and second feedthrough connectors 5, 6, respectively. Directly at the feedthrough connector 5, 6, the 29 power lines 7 are interconnected, so that all power lines 7 are connected in parallel. In the second connection unit 3, the detection line 8 is additionally connected to the power lines 7. In this way, the internal resistance of the power lines can be monitored in both the forward line 19 and the return line 20.

[0055] The source 14 generates between 0 and 100 volts of direct voltage and a direct current of up to 20 amperes. This direct voltage is applied between the power lines 7 of the supply line 18 and the power lines 7 of the return line 19. An auxiliary voltage, for example a voltage of 10 volts, is branched off from the voltage at the first connection connector 12 by means of a voltage regulator 21. This auxiliary voltage supplies a microcontroller 22 and a separate analog-to-digital converter 23. The analog-to-digital converter 23 is equipped with four channels and is connected to the power lines 7 of the supply line 19, the detection line 8 of the supply line 19, the power lines 7 of the return line 20, and the detection line 8 of the return line 20. This allows a digital value for each of the applied potentials to be determined and input to the microcontroller 22.

[0056] The microcontroller 22 or the program code running there forms a potential difference on the forward line 19 and a potential difference on the return line 20 from the potentials. If one of the potential differences exceeds a predefined limit value, the microcontroller 21 generates a trigger signal 17 and outputs it to a switching device 18, which in this case is formed by a MOSFET.

[0057] Fig. 3 shows an embodiment of a method according to the present disclosure. The method can be implemented using the arrangement according to Fig. 1 or Fig. 2 are executed.

[0058] In step S1, electrical energy is conducted from the source 14 to the sink 15 by means of at least one power line 7 of a feed-through cable 4.

[0059] In step S2, a potential difference between the at least one power line 7 at the first connection unit 2 and the at least one power line 7 at the second connection unit 3 is detected using at least one detection line 8 of the feed-through cable 4. In this way, the voltage drop across a power line can be determined.

[0060] In step S3, the detected potential difference is compared with a predefined limit value.

[0061] In step S4, a trigger signal is generated and output if the potential difference exceeds the predefined limit. This allows for an appropriate response in the event of an impermissibly high voltage drop across the power lines, for example, by switching a switching device 18 to a non-conductive state.

[0062] With regard to further advantageous embodiments, reference is made to the general part of the description and to the appended claims in order to avoid repetition. List of reference symbols 1 arrangement 2 first connection unit 3 second connection unit 4 feed-through cables 5 first feedthrough connector 6 second feedthrough connector 7 Power line 8 Detection line 9 Implementation 10 Outdoor space 11 Interior 12 first connection connector 13 second connection connector 14 Source 15 depression 16 detection unit 17 Trigger signal 18 Switching device 19 Introduction 20 Return line 21 voltage regulators 22 microcontrollers 23 analog-to-digital converters

Claims

[1] Arrangement for transmitting electrical energy from a source (14), preferably a photovoltaic system, to a sink (15) through a slot-like feedthrough (9), preferably a window gap, comprising a first connection unit (2), a second connection unit (3) and a feedthrough cable (4) connecting the first and the second connection unit (2, 3), wherein the feedthrough cable (4) is designed to pass through the feedthrough (9) and has at least one power line (7) and at least one detection line (8), wherein the at least one power line (7) is designed to transmit electrical energy from the source (14) to the sink (15), wherein the at least one detection line (8) in the second connection unit (3) is connected to the at least one power line (7), wherein the first connection unit (2) has a detection unit (16) which is connected to the at least one detection line (8) and the at least one power line (7), and wherein the detection unit (16) is designed to detect a potential difference between the at least one power line (7) and the at least one detection line (8) and to generate and output a trigger signal (17) when a predefined limit value is exceeded by the potential difference. [2] Arrangement according to claim 1, characterized by in that the first connection unit (2) has an analog-digital converter (23) for generating a digital value, wherein the digital value is representative of a potential on the at least one power line (7) and / or a potential on the at least one detection line (8) and / or a potential difference between at least one power line (7) and at least one detection line (8). [3] Arrangement according to claim 2, characterized by that a voltage reducer is arranged between the analog-digital converter (23) and the at least one power line (7) and / or between the analog-digital converter (23) and the at least one detection line (8), which voltage reducer reduces a detected potential in a defined ratio or by a defined amount. [4] Arrangement according to one of claims 1 to 3, characterized by that the first connection unit (2) is designed such that a negligibly small current flows through the at least one detection line (8) relative to a current through the at least one current line (7). [5] Arrangement according to one of claims 1 to 4, characterized by that the first connection unit (2) comprises a switching device (18) which, in normal operation, enables a current flow through the feed-through cable (4) and, in a disconnected state, disconnects the current flow. [6] Arrangement according to claim 5, characterized by that the switching device (18) is communicatively connected to the detection unit (16) and is designed to receive the trigger signal (17) and that the switching device (18) changes from normal operation to the disconnected state upon receipt of the trigger signal (17). [7] Arrangement according to one of claims 1 to 6, characterized by in that the feed-through cable (8) is formed by a flexible printed circuit board, wherein a plurality of longitudinally extending conductor tracks are arranged on the flexible printed circuit board, wherein at least one of the plurality of conductor tracks forms the at least one detection line (8) and at least one of the plurality of conductor tracks forms the at least one current line (7). [8] Arrangement according to one of claims 1 to 6, characterized bythat the feed-through cable (4) is formed by a ribbon cable with a plurality of individual conductors, wherein at least one of the plurality of individual conductors forms the at least one detection line (8) and at least one of the plurality of individual conductors forms the at least one power line (7). [9] Arrangement according to one of claims 1 to 8, which comprises a feed-through cable (4) for a forward line (19) and a feed-through cable (4) for a return line (20), wherein the feed-through cable (4) for the forward line (19) and the feed-through cable (4) for the return line (20) are preferably formed separately from one another. [10] Arrangement according to one of claims 1 to 9, characterized byin that in a feed-through cable (4) with a plurality of power lines (7), the plurality of power lines (7) are connected in parallel, wherein the ends of the plurality of power lines (7) on the side of the first connection unit (2) and / or on the side of the second connection unit (3) are each preferably connected together at a connection point of the feed-through cable (4) with the respective connection unit (2, 3). [11] Arrangement according to one of claims 1 to 10, characterized by that the feed-through cable (4) is detachably connected to the first connection unit (2) and / or to the second connection unit (3). [12] Arrangement according to one of claims 1 to 11, characterized by that the first connection unit (2) and the second connection unit (3) each have a connection connector (12, 13) for connecting to the source (14) and / or the sink (15), preferably an MC4-compatible or MC4 Evo2-compatible connector. [13] Arrangement according to one of claims 1 to 12, characterized by that the feed-through cable (4) has a length of a maximum of one meter, preferably a maximum of 50 centimeters, particularly preferably a maximum of 30 centimeters. [14] Arrangement according to one of claims 1 to 13, characterized by that the feed-through cable (4) has at least one bending-resistant insert, wherein the at least one bending-resistant insert is arranged parallel to the at least one power line and / or the at least one detection line and is designed to limit a bending radius of the feed-through cable to a minimum bending radius. [15] Arrangement according to one of claims 1 to 14, characterized by a transmission power of up to 300 watts, preferably up to 600 watts, particularly preferably up to 800 watts, further preferably up to 1000 watts. [16] Method for transmitting electrical energy from a source (14), preferably a photovoltaic system, to a sink (15) through a slot-like feedthrough (9), preferably a window gap, using an arrangement (1) according to one of claims 1 to 15, wherein the arrangement (1) has at least a first connection unit (2), a second connection unit (3), a feedthrough cable (4) connecting the first and the second connection unit (2, 3) and guided through the feedthrough (9), and a detection unit (16), comprising: Conducting (S1) electrical energy from the source (14) to the sink (15) by means of at least one power line (7) of the feed-through cable (4), detecting (S2) a potential difference between the at least one power line (7) at the first connection unit (2) and the at least one power line (7) at the second connection unit (3) using at least one detection line (8) of the feed-through cable (4), Comparing (S3) the potential difference with a predefined limit and Generating and outputting (S4) a trigger signal (17) when the potential difference exceeds the predefined limit value.

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