WO2011063803A2

WO2011063803A2 - Module switch, solar module, solar cable, busbar, and device

Info

Publication number: WO2011063803A2
Application number: PCT/DE2010/050085
Authority: WO
Inventors: Ingo Müller
Original assignee: Mueller Ingo
Priority date: 2009-11-27
Filing date: 2010-11-26
Publication date: 2011-06-03
Also published as: DE102009044695A1; WO2011063803A3; DE112010004570A5

Abstract

The invention relates to solar modules (24, 64, 74, 84, 94) having at least two solar cell strings (25, 65, 75), wherein each string is galvanically isolated from the other strings. The invention further relates to solar modules that comprise a series diode (26), for example a Schottky diode, which is connected in series with the solar cells of the string so that the voltage provided by the solar cells polarizes the series diode in the flow direction. The invention further relates to module switches. A module switch comprises a control input (111) and a switching output (116) for short circuiting a solar module string. If an electrical signal below the threshold value is present at the control input (111), the two electrical connections of the switching output (116) are interconnected at low resistance, otherwise at high resistance. The invention further relates to solar cables having several electrical conductors insulated from each other. The invention further relates to busbars (8, 9) for solar systems, which have plug-in connectors for solar cables (33, 34, 35) having several electrical conductors. Finally, the invention relates to multiple-contact plug-in connectors for solar cables.

Description

Modular switch, solar module, solar cable, busbar and device

The field of the invention are photovoltaic systems and in particular solar modules as well as safety devices such as module switches for this purpose.

Module switches according to the preambles of claims 1 and 3 and solar modules according to the preamble of claim 10 are known for example from DE 10 2007 032 605 A1.

Photovoltaic has been used successfully for more than 50 years, first as a power supply in space technology, then in experimental facilities and due to government incentives in ever greater numbers and with increasing performance of individuals. Nominal values of current and voltage have meanwhile increased considerably and with it the effects of an arc fault.

A circuit diagram of a conventional photovoltaic system 1 is shown in FIG. 29. It usually consists of a photovoltaic generator 2 and one or more inverters 3 or charge controllers, unless the consumer is fed directly from the photovoltaic generator 2. In this document, an inverter 3 is always exemplary also for multiple inverters, one or more charge controllers or one or more other consumers and can be replaced by them. The photovoltaic generator 2 is usually constructed of a plurality of solar modules 4, which are connected in series with one or more strings 5. When operating multiple strings 5 to a common inverter 3 or charge controller, the strings 5 can be connected in parallel via two bus bars 8 and 9 with each other. In this case, to exclude reverse currents in a string, each string has a series diode 6. A fuse 7 in each string is to separate the corresponding string from the rest of the photovoltaic system 1 in case of defects. Bypass diodes in the solar modules carry the current of the unshaded modules of the string in case of shading of the module.

Usually all solar cells within a module are connected in series to keep the number of external contact points low. In Fig. 30, a solar module 14 is shown with multiple substrings 15 within the solar module 14, wherein the substrings 15 are not led out individually, but are connected in parallel in the junction box 17. In another embodiment according to the prior art, the substrings 15 can also be connected in parallel in the cell array. As a result, many modules feature the 150mm x 150 now used mm solar cells rated currents> 5 A up. The bypass diode 18 in the solar module 14 carries in the case of shading of the module, the stream of unshaded modules of the string.

FIG. 31 shows a circuit diagram of a solar module 14. In the systems, only inadequate provisions for arc protection are usually made. There are now improved connectors and junction boxes. The measures are essentially aimed at reducing the probability of failure at the contact points, e.g. optimized plug contacts and the prevention of water ingress as well as a reduction in the arc consequences such. Junction boxes made of aluminum (Elektroprofi 2/2008, p. 43 - 45). There are also special UV-resistant solar cables and cable ties. In addition, the isolation of solar cables from an arc-inhibiting material, for. B. consist of irradiated polyamide 66. If an arc occurs, the arc-inhibiting material will escape and / or evaporate partially. Thus, the arc plasma is deprived of energy and the arc extinguished. All these measures can not avoid the actual arc.

An arc in the system can be detected (US 2006/0171085 A1, US 6,259,996 B1, US 6,633,824 B2, especially for photovoltaic systems: WO 95/25374 AI), only there is up to now no way to the arc in a photovoltaic Plant react. How switching devices in photovoltaic systems are to be used for the reaction to an arc is described in I. Müller: "Arc Fault Protection in the DC Part of Photovoltaic Systems", Wissenschaftsverlag Ilmenau, 2002, ISBN: 3-936404-02-X (in the following: Müller02) described. There, whole strings are switched. Moreover, EP 1 709 504 B1 uses the method described in Müller02 on solar sources of spacecraft.

An inherently effective method which can avoid the arc is based on the use of capacitors and is described in WO 2004/010556 A3. Unfortunately, due to the high temperatures on the roof when exposed to solar radiation, the capacitors required for this purpose can not be procured on the market with sufficient life expectancy. But they could be developed.

The photovoltaic generator can be switched off by means of DC switch disconnectors in accordance with DIN VDE 0100-712, which is usually only available on the inverter. The modules are then still under tension, so that for persons acting in the vicinity of the plant, for example during assembly or fire, a risk can not be excluded.

US 2009/01 14263 A1 discloses switchable modules which separate the module contact to the rest of the system by means of a switching device used in series (contact or electronic). This can not be used with higher string voltages because the first opening contact always sees the entire string voltage (ULL - UMPP, no-load voltage - voltage at the maximum power point, see UL characteristic for module, Fig. 2) and is therefore subject to considerable wear and tear must be measured. Also in DE 10 2007 032 605 A1 with family members WO 2009/006879 A2 and EP 2 168 173 A2, the inventors propose solutions for switching off photovoltaic systems. According to this document, the photovoltaic system is composed of individual photovoltaic modules, which are connected in groups in series (so-called "string") and possibly several groups in parallel. The photovoltaic module shown in Fig. 4 of DE 10 2007 032 605 A1 has a control unit with amplifier and receiver, which serves to switch a relay, in particular of the switch 24 integrated therein. By closing the switch 24, an internal short circuit in the photovoltaic module can be generated, so that a potential equalization between the terminals of the photovoltaic module is produced. This ensures that the outside of the photovoltaic module no hazardous or even disturbing or voltage to be controlled is applied or power [she!] Flows. For example, it is no longer possible to obtain an electric shock when the outer contacts of the photovoltaic module are touched because there is no longer sufficient potential difference there and the photovoltaic module has been internally short-circuited. In all embodiments, the control signal can be transmitted by, in particular, radio, light, electric (generally electromagnetic) or triggered internally by means of sensors, etc. By disconnecting the inverter, the closed circuit is first interrupted and the individual modules must withstand much less current flow than with a closed circuit. As a result, the modules do not have to be switched off at exactly the same time so as not to damage them.

This method corresponds to a special case of the use described in Müller02 switching devices in the immediate vicinity of the energy converter, so the solar modules of photovoltaic systems, but without the peculiarities when used in substrings consider. For larger systems modules and / or switching devices are overused or have impractical designs and thus too high costs. For safety reasons disadvantageous are the lack of intrinsic safety and the complicated by the involvement of the DC main switch and fault-prone switch regime until it reaches a safe state.

Usually, the module junction boxes have a single volume, in which all contact points are embedded on a common terminal block.

Solar cables only consist of a single core.

Usually, the solar cells are embedded in EVA (ethylene-vinyl acetate). The rear wall consists of a more or less flammable plastic.

It is an object of the invention to provide safe solar modules, module switches, safe solar cables, secure busbars and secure connectors.

This object is achieved by the teaching of the independent claims.

Preferred embodiments of the invention are subject of the dependent claims. In the following, a preferred embodiment of the invention will be explained in more detail with reference to the accompanying drawings. Showing:

1 shows a solar module according to the invention;

FIG. 2 shows the characteristics of a single-string arrangement and arcs of different lengths; FIG. 3 shows the characteristics of a string of a multi-string arrangement and different length arcs;

Fig. 4 and 5 according to the invention solar modules;

6 and 7 show the structure of photovoltaic systems according to the invention;

8 shows the construction of a photovoltaic system according to the invention in a fishing net topology;

9 shows a general, inventive module switch. 10 to 14 different embodiments of a module switch according to the invention, in which the electrical isolation and the short-circuiting of the solar modules takes place by means of relays;

15 to 18 different embodiments of a module switch according to the invention, in which the short-circuiting of the solar modules by a npn

Transistor takes place;

FIGS. 19 to 22 show various embodiments of a module switch according to the invention, in which the short-circuiting of the solar modules takes place by means of a PMOS; Figure 23 is a topology in which two out of phase control signals are used;

FIGS. 24 and 25 show embodiments of a module switch according to the invention for 2 antiphase control signals;

Fig. 26 and 27 solar cable according to the invention; 28 shows a cross section through a solar module according to the invention;

Fig. 29 is a circuit diagram of a conventional photovoltaic system;

FIG. 30 shows a solar module with several partial strings; FIG. and

Fig. 31 is a circuit diagram of a solar module.

FIG. 1 shows a solar module 24 according to the invention, which consists of a solar cell array 22 and a module junction box 27. The solar cell array 22 comprises the solar cells 21, which are connected together in a one-dimensional array of a plurality of partial strings 25. Each partial string 25 consists of a series connection of a plurality of solar cells 21. Each partial string 25 has a plus terminal 30 and a minus terminal 31. The positive terminal 30 is at the same time the anode terminal of the solar cell of the corresponding partial string which is shown at the top in FIG. The negative terminal 31 is the cathode terminal of the solar cell of the corresponding partial string, which is shown at the bottom in FIG. In addition, each partial string 25 may have one or more taps 32 which divide the partial string 25 into partial string sections. Each partial string section in a solar cell array 22 contains the same number of solar cells 21 in one embodiment. To each substring section is a bypass diode 28 connected in anti-parallel. In addition, a switching element 23 is connected in parallel to each Teilstringabschnitt, which shorts the Teilstringabschnitt when the switching element is not opened by a control element 29 for normal operation. The switching elements 23 can therefore be referred to as "normally closed". Hereinafter, the open high-resistance state of the switching element 23 is referred to as the operating state and the closed state as the ground state.

In the embodiment illustrated in FIG. 1, all the bypass diodes 28, all the switching elements 23 and the control element 29 are accommodated in the module connection box 27. As a result, existing solar modules can be retrofitted at least partially. For this purpose, it is necessary that the contacts between the solar cell array 22 and the module junction box 27 are easily separable, so for example pluggable realized via a plurality of plugs and corresponding sockets, which are mechanically connected to each other in the solar cell array and in the module junction box. On the other hand, this requires that not only the positive terminals 30 and the minus terminals 31 must be led to the module junction box 27, which is required anyway, but also all the taps 32nd

In order to ensure better heat dissipation from the bypass diodes 28 and the switching elements 23 and also to simplify the cable guide in the solar module 24, in another embodiment, the bypass diodes 28 and the switching element 23 can be mounted distributed over the solar module. In this embodiment, the connections between the solar cell array 22 and the module junction box 27 may be hard-wired, which may be cheaper and more reliable.

In the module junction box 27 further series diodes 26 are housed, wherein a series diode 26 is connected in series with each sub-string 25. The series diodes 26 are advantageous in a fishing net topology illustrated in FIG. 8 and prevent defects in solar modules during shutdown. The latter will be explained in more detail in connection with FIG. 7. At the module junction box a Plussolarkabel 33 and a Minussolarkabel 34 is connected. The connection between the solar cables 33 and 34 and the module connection box 27 can either be fixed or detachable. In the case of a detachable connection, each solar module 24 may be supplied with two preassembled solar cables 33 and 34. Each of the solar cables 33 and 34 has for each sub-string 25 an electrical conductor 36 which is electrically connected to the corresponding sub-string 25. Each solar cable 33 and 34 has at the loose end, where it is not is connected to the module junction box 27, a contact point, so that the loose end of a Plussolarkabels 33 can be connected to the loose end of a Minussolarkabels 35 of another solar module or the plus busbar. Contact or point of contact is used in this document as a generic term for plug and socket.

As can be seen from Figures 29, 6, 7 and 8, the solar modules 4 are connected in series and thus form strings 5. This is done in a conventional manner, so that when mounting a solar cable the newly installed solar module with a solar cable of the previously mounted Solar module is connected. The solar modules 24 according to the invention can thus be mounted in the same way as the conventional solar modules 4 in an advantageous manner. For reasons of better heat dissipation from the switching elements and / or string diodes and the better thermal stability, it is advantageous to highlight the module junction boxes 27 made of metal, in particular aluminum.

It is important for one aspect of the invention that all partial strings 25 of a solar module are electrically insulated from one another, ie are electrically isolated. Even after the assembly of all the solar modules 24 according to the invention of a photovoltaic generator 2, in one embodiment of the invention, the partial strings 25 are connected in parallel only on the busbars 8 and 9.

Bypass diodes 18 are known at the solar module level, as shown in FIG. The provision of a bypass diode 28 for each Teilstringabschnitt results in more favorable behavior in partial shading of the module, because only the actual (partially) shaded Teilstringsabschnitte fail and not the entire module. In this respect, the division of a module into partial strings or partial string sections is the prerequisite for better performance with partial shading. As bypass diodes 28 and / or series diodes 26 Schottky diodes can be used advantageously due to the lower forward voltage. The lower forward voltage reduces the heat dissipation requirements while increasing efficiency.

The aim of the division into substrings is to reduce the currents in the live conductors and provided and not provided contact points. Provided contact points may be, for example, connectors. Unintended contact points are fault locations, that is, for example, bad, corroded contacts or wire breaks. As is known from Müller02, the conditions of existence for an arc deteriorate when the current in a string or Substring decreases. At a current <2 A, the arc already burns significantly more unstable than at 5 A or 8 A, below 0.5 A, it can no longer exist because the amount of charge carriers generated is no longer sufficient to maintain an arc discharge. Conveniently, one chooses a partial current <1 A as a compromise between deterioration of the conditions of existence and costs.

Compared to the single-string arrangement, in the case of the multi-string arrangement with the same nominal power, only significantly smaller arc lengths with significantly smaller power over the fault location are possible, if at all.

As an additional measure against transverse defects, in FIG. 1, each contact to a vein of the positive and negative solar cable is housed in a separate chamber 38. Thus, a sufficient insulation of the contacts is more likely, even if the cable insulation is brittle or loose contact points.

Using the example of Figures 2 and 3, the operating principle for a split into 8 partial strings with a total of the same power and identical rated voltage is illustrated. In FIGS. 2 and 3, the string or partial string voltage is shown at the top and the string or partial string current is drawn to the right. FIGS. 2 and 3 show three characteristic curves 42, 43 and 44 of arcs for different arc lengths, l ₂ and l _3, respectively. In Figure 2, a characteristic curve 41 of a conventional solar module with a single string and about 5 A current at the point of maximum power 45 is also entered, in which the solar module is normally operated, which corresponds to about 8 A short-circuit current l _k . From Figure 2 it can be seen that an arc of length with a stable operating point 46 can exist. Since the characteristic curves 43 and 44 intersect the characteristic curves 41, arcs with a greater length l ₂ or l _{3 can also} exist. FIG. 3 shows the characteristic curve 51 for a partial string which supplies only one-eighth of the current of the individual string whose characteristic curve 41 is shown in FIG. The maximum power point 55 is at the same voltage U _M pp as point 45, but only at one-eighth of the current. The short-circuit current of the substring in FIG. 3 is approximately 1A. An arc of length may only exist in the small area above point 56. Arcs of lengths l ₂ and l ₃ can not exist for lack of an intersection of the characteristic curves 43 and 44 with the characteristic 51. If one were to increase the number of substrings from 8 to 9 and thus lower the current by a further 1 1%, arcs of length would no longer be possible. Compared with the conventional single-string arrangement in FIG. 2, in the case of the multi-string arrangements, only substantially smaller arc lengths with significantly smaller power over the fault location are possible, if at all.

FIG. 4 shows a solar module 64, which is similar to the solar module 24 shown in FIG. Essentially, the partial strings 25, which are represented in FIG. 1 by the series-connected solar cells 21, have been replaced by circuit diagrams for solar modules 65. Each partial ring 65 can be shorted overall via a switching element 63, since it consists of only one section. The switching elements 63 are controlled by a control 29. The series diodes 26 are also shown explicitly. Bypass diodes may be part of the substrings 65. All connections to a Plussolarkabel and all connections to a Minusolarkabel are housed in two separate chambers 69 and 68, respectively.

FIG. 5 shows a new circuit diagram for a solar module 74 according to the invention. The solar module contains H partial strings 75, which can be short-circuited under control of the control element 29. It is not specified whether, as in FIG. 1, individual partial string sections can be short-circuited by switching elements 23 or, as in FIG. 4, each partial string can be short-circuited by a corresponding switching element 63.

FIG. 6 shows the structure of a photovoltaic system 81 according to the invention with a photovoltaic generator 82 according to the invention and an inverter 3. In contrast to a conventional photovoltaic generator 82, a series diode 86 and a fuse 87 are provided for each partial string. The individual substrings are electrically connected only on the busbars 8 and 9.

The solar modules 84 according to the invention shown in FIG. 6 have neither switching elements for short-circuiting the partial strings or partial string sections nor a control element. For easy installation, the busbars 8 and 9 should be equipped with multi-pole contact points 88, 89 for multi-pole solar cable.

FIG. 7 shows the structure of a photovoltaic system 91 according to the invention with a photovoltaic generator 92 according to the invention and an inverter 3. In contrast to the solar modules illustrated in FIG. 6, the solar modules 94 in FIG. 7 have switching elements and one control element 29 each. All control inputs of the controls 29 are connected in series. In addition, one or more emergency switch 95 and a control signal source 96 is provided which in normal operation the Provide controls 29 with electrical energy, so that the individual substrings or Teilstringabschnitte the solar modules are not shorted. In case of fire, the fire department can open the emergency switch 95 or disconnect a connection 97, whereby the partial strings or partial string sections are short-circuited, so that a safe fire fighting is possible. The emergency switch or switches can also be designed as thermal fuse or thermal fuses, so that the solar system is switched off automatically at too high a temperature in one place. The control signal source 96 is usefully designed as a power source to control photovoltaic generators 92 with a different number of solar modules 94.

For ease of installation, the busbars 8 and 9 should also be equipped with connectors for multi-pole solar cables. However, the wiring in the connectors and between the busbars is somewhat more complicated than in Figure 6, because all the controls 29 are to be connected in series and thus electrical connections 97 between the attached to the busbars 8 and 9 connectors are needed.

In another embodiment, only the controls 29 of a string can be interconnected to form a control string in series. All control strings are then switched in parallel. In this case, the control signal source for a given number of series-connected solar modules can also be designed as a voltage source or you can adjust the voltage supplied by the control signal source step by step to the number of solar modules in a string. If the control signal source operates as a current source, in this embodiment also the height of the control current can be adjusted stepwise to the number of strings.

The control signal source can draw their energy on the one hand via the lines 99 from the power grid and thus also from the inverter 3. Additionally or alternatively, the control signal source 96 may also be connected to the DC power circuit of the photovoltaic system 91, that is to say to the busbars 8 and 9 via the lines 98. If the lines 99 are missing, there is the problem that the solar modules provide too low a voltage during the day when the switching outputs 1 16 of the module switches are in the low-resistance state, that is, when the photovoltaic system 91 is in the ground state. If, on the other hand, by meaningful design of the switching outputs, ensures that, despite the ground state The busbars are applied to a non-hazardous voltage in the range of about 10 V, you can for example by a DC-DC converter with another input voltage range from this residual voltage generate a sufficiently strong control signal, so that by closing the or all emergency switch 95, the photovoltaic Annex 91 can put in the operating condition. Due to the residual voltage in the ground state, the photovoltaic system 91 is self-sufficient.

The emergency switch 95 may also be built in the control signal source 96. The control signal source 96 may possibly be installed together with an emergency switch 95 in the inverter 3 or a charge controller. The latter integration is also advantageous because the inverter 3 or the charge controller can switch off the photovoltaic generator 92 even if there is a defect in the inverter 3 or charge controller or these devices overheat.

In order to achieve high safety of the photovoltaic system, it is necessary that each string of the photovoltaic system can be switched independently of the state of the other strings. Furthermore, it is important that the photovoltaic system is not damaged during switching operations. To achieve these goals serve the series diodes 86 and 26th

To justify the need for the series diodes 86 and 26, it is assumed that the series diodes 86 and 26 are not part of the photovoltaic system. Because of component tolerances and signal runtime differences in the photovoltaic system virtually all partial strings of a string A can be switched off at the same time, it can be assumed that a substring of a string A will be the last switched. In this case, the voltage between the busbars of the photovoltaic system, which can be several hundred volts, is above the last-connected partial string.

The same chain of events results from the buffer capacitor at the DC input, which is practically present in every inverter, also for the last switched-off string.

The voltages between the busbars of common photovoltaic systems in the range of 100 to 900 volts, depending on the number of cells of the switched substrings, the permissible reverse voltage of the individual solar cells, which is in the range around 15V exceeded. Then there is an irreversible damage to the pn junctions of the affected solar cells and consequently to follow-on errors. Under unfavorable Circumstances, these are not noticed immediately. Thus, in addition to a reduction in yield and local thermal overheating may arise.

The series diodes 86 prevent polarity in the reverse direction and thus the flow of a significant reverse current and damage to the non-short-circuited partial string sections. As already shown in FIGS. 1 and 4, a plurality of series diodes 26 can also be used in one string, namely for each string in each solar module 24, 64 and 74. This has the advantage that the total blocking voltage of the series diodes 26 scales with the voltage between the bus bars because the number of solar modules connected in series is both proportional to the total blocking voltage and to the voltage between the bus bars. It should be noted that the series diodes 26 are not short-circuited by the switching elements 23 or 63. As shown by way of example in FIG. 9, the series diodes 126 can also be installed in the module switches 110, 120, 140, 150, 170, 180, 190, 210, 230, 250, 270, 280, 320 and 340. FIG. 8 shows the construction of a photovoltaic system 101 according to the invention with a photovoltaic generator 102 according to the invention in a fishing net topology and an inverter 3. In contrast to the topology shown in FIG. 6, additional bus bars 108 are provided as cross connections between the individual partial strings. With this, it is possible to ensure that no arc burns throughout the entire network. If the nominal module voltage is limited to values <15 V, a stable arc can no longer exist in the event of a transverse fault across a module, an arc in the case of a longitudinal fault is excluded even at nominal module voltages <55V, since in this fault, the difference between no-load voltage and maximum power voltage represents the maximum available voltage for the arc. The fishing net topology is also suitable for the known embodiments of solar modules.

Figure 9 shows a general module switch 1 10 with a control element 29 and a switching element 1 13. The module switch 1 10 is a quadrupole with a two-pole control input 1 1 1 and a two-pole switching output 1 16, which is connected in parallel to a string or partial string, the can be closed by the switching element 1 13 short. The module switch further comprises a series diode 126 connected in series with the switching output 16 and the string 15. As explained above, the series diode prevents the flow of a reverse current above critical values through the string 1 15. The control element 29 comprises a signal receiving circuit 12 and a driver stage 1 14, wherein the signal receiving circuit 1 12 and the driver stage 1 14 are coupled galvanically isolated. The signal receiving circuit 1 12 is electrically connected to the control input 1 1 1. The driver stage 1 14 is coupled to the switching element 1 13. In the embodiments of a module switch shown below and in FIGS. 10-21, a distinction is no longer made between substring and string, but string is used as a generic term for string and substring.

Optionally, the module switch 1 10 still contain a display element 1 17, which is supplied in an advantageous manner with solar energy from the string. Optionally, the display element 1 17 have a display output 1 18, via which the state of the switching element is transmitted to a remote display device wired or wireless and displayed there. The remote display device may be located, for example, in the inverter 3.

1) The galvanic isolation can be realized: a) (electro) magnetically by a magnetic circuit with contacts, namely an electromechanical relay, preferably a reed relay or a magnetic circuit with Hall element or b) optically by

A) an opto-coupler with discrete components, namely i) a transmitter, which may consist for example of an incandescent lamp, light emitting diode (LED) or gas discharge lamp and a receiver, for example, a photothyristor, a photoresistor, a photodiode or a

Phototransistor may exist or as an integrated component containing transmitter and receiver. C) inductively by a transformer, also a multi-phase transformer or inductively coupled resonant circuits, which ultimately represent a transformer; d) capacitively by means of a capacitor arrangement. In addition, components are possible which already contain a galvanic isolation: e) DC / DC converters, in particular for driving MOSFETs, but also bipolar transistors; f) isolation amplifier; g) Solid state relay (solid state relay).

Finally, there are special cases in which there is a spatial division of the galvanic separation: h) control with optical (fiber) cable; i) coil arrangement with / without core (for example frame coil in the module and induction loops in the generator) k) electromagnetic field (radio) without or with protocol (eg Bluetooth, ZigBee, WLAN, RFID).

Series and parallel circuits in the signal receiving circuit of the control of a module, preferably in windings (relays) and optocoupler transmitters are possible (see Fig. 13). But also in the output of the driver stage, if several switching elements are to be controlled.

The control circuit can be operated with DC and / or AC voltage. When alternating voltage is used, rectification and screening may be required (see Fig. 19). The transmission of the control signal can also be conducted with a transmission protocol (eg CAN bus). This requires the use of sequential circuits or even microcontrollers in the control. Even when using transmission protocols, it should be checked whether a valid protocol is available. If this is not the case (loss of signal), the module switch should, as a precaution, change to the non-hazardous basic state. This corresponds to the Comparison with a threshold if the module switch is controlled with DC and / or AC voltage or current.

The galvanic isolation can also be done with multiple isolation links in chain circuit, for example by the combination of transformer and optocoupler. A DC / DC converter with wide voltage input range of e.g. 1 -60V, if necessary with extra stabilization, can be provided for self-supply of the control by means of the power produced by the module itself.

Conveniently, the control contains threshold behavior and hysteresis, so that the switching element does not leave the safe working area in the output characteristic field.

As a threshold and / or driver stage operational amplifier can be used.

The control signal and the signal receiving circuit can also be multi-phase, in particular out of phase, designed. This can increase the immunity to interference. 2) The switching element may be embodied as an electrically operable contact or controllable semiconductor, that is, for example, a) a contact which is part of a relay, preferably a reed relay; b) a bipolar transistor; c) a field effect transistor, e.g. a MOSFET self-conducting or self-locking; d) an IGBT (Insulated Gate Bipolar Transistor); e) a thyristor, for example, with auxiliary circuit for deletion; f) a triac, for example with auxiliary circuit for deletion;

In the basic state (solar radiation on module, no control signal), the switching element is closed; either by execution as a normally closed contact (normally closed) or by a self-holding circuit. At the externally accessible terminals of the module is then at a safe voltage, which is significantly lower than the rated voltage of the module, ie 0V to a few volts. It is possible to realize <3 V over a single module switch. The advantage of short-circuiting unlike US Patent 2009/01 14263 A1 with switching contact in series with the module is that over the switching path is not applied substantially more than the open circuit voltage of the string (see Fig. 2, characteristic 41).

The switching element can also be realized by combining several switching elements in the form of a series or parallel connection or by push-pull or bridge circuit. The provision of the corresponding necessary voltage potentials and control currents is ensured by the driver stage.

3) The optional display element for indicating the operating state of a string can comprise one or more of the following components: a) an LED b) an incandescent lamp c) a gas discharge element d) a coupling element (eg optocoupler) for transmitting the state to a remote one Display or evaluation unit. The display element may be coupled to control signal circuit, driver stage and / or switching element and display current and / or voltage values.

Display for the switching state preferably on the sunny side of the module, but can also be mounted on / in junction box. For example, with extra holes for LED or translucent housing (construction) parts of the junction box such. the can lid.

The display element may also have window discriminator behavior, e.g. Display of a voltage value of 1, 5 V to 3 V, have.

If you want to retrofit existing solar modules with modular switches for safety reasons, the module switches should be prepared for this task. This can be achieved in a simple manner in that the two poles of the switching output 1 16 are each performed twice, so that there is a connection for a string of solar cells and a solar cable at each pole.

Figure 10 shows an embodiment of the module switch 120, in which the control element 122 and the switching element by a relay with relay coil 131 and Normally closed contact 123 are formed. A diode 132 short circuits inductive voltages as occur when the current through the relay coil 131 is turned off. In the ground state, the normally closed contact 123 is closed, ie the module voltage is close to 0 V, ie <3 V. About the shunt resistor 133 (0.47 Ω) falls from a low voltage to the series resistor 135 (27 Ω), the LED 134 with Supplying electricity and letting it shine. However, the operating state can also be displayed via the LED 138, which is supplied with power via the diode 136 and the series resistance 137 (2.2 kΩ). The breakdown voltage of the zener diode 136 is greater than the voltage at the string 1 15 in the ground state, ie> 3 V, so that certainly no current flows through the LED 138 in the ground state and thus the LED 138 certainly does not light.

It is safer to explicitly display only a dangerous condition because a display device may also be defective. If nothing is displayed, it is always assumed that there is a danger, as it also occurs when using the previously used modules. So if only one LED is to be used, the LED 134 is to give preference. In this embodiment, if the fire brigade sees the module lights illuminated, it can safely extinguish with water in the event of a fire. Against this background, the base state LED 134 should be green and the operating state LED 138 should be red. The colors can be awarded in other embodiments but also different. The light of the LEDs can also be transmitted via fiber optic cable to a remote display, for example in or at the charge controller.

Relays have two advantages over purely electronic solutions: a) they allow startlingly simple and cost-effective solutions with high signal-to-noise ratio (safety-relevant component) b) only a relatively low power loss occurs in the connection socket due to the ohmic losses of the relay winding. An additional cooling can be dispensed with mostly.

The wear caused by the mechanical parts and the contacts is of minor importance in the few expected switching operations.

The components in the display element 127 can also be omitted. Then, the shunt resistor 133 can be replaced with a conductor. This reduces the power loss occurring in the module junction box. FIG. 11 shows a module switch 140 which differs from the module switch 120 only by the optocouplers 141 and 142 (both for example MB104C). The LEDs 134 and 138 are part of the optocouplers 141 and 142 in the module switch 140. The phototransistor of each of the two optocouplers 141 and 142 forms a display output 5 143 and 144 respectively. Corresponding display outputs of the module switches of several solar modules can be connected in series, so that the actual State of multiple solar modules is summarized and displayed on a remote display. The remote display can be advantageously attached to the inverter 3 or integrated into the housing of the inverter 3. The more Kabel0 are returned from the display outputs of the solar modules of a photovoltaic system to the display, the more accurate a faulty solar module can be determined. It is advantageous, in particular, to connect all the corresponding display outputs of the module switches of a string or of a substring or of a substring section in series and to feed them back separately for display. 5 An indication of the condition of the system is possible by monitoring the voltage at the busbars. This is evaluated by the inverter anyway and displayed if necessary. In another embodiment, the voltage at the busbars may also be compared to a threshold value. If, in the operating state, the voltage on the busbars is above the threshold value, a red lamp on the inverter may be switched on. If the voltage on the busbars is below the threshold, a green lamp on the inverter may be on.

However, when evaluating the voltage at the busbars, there is the risk that this can also be very low due to system errors, such as line interruption in the event of a partial destruction of the system. It would then erroneously displayed a safe state of the system, although system parts are still under tension. In this respect, the display of the safe state by means of the display elements has significant advantages in terms of safety, because this only takes place when there is actually no voltage. FIG. 12 shows a module switch 147 with a relay which has a relay coil 131 and three mutually galvanically isolated normally closed contacts 123 for short-circuiting three strings 15. A display element and a shunt resistor are absent in this embodiment. With appropriate dimensioning of the solar cells in the strings 15 and 15 of the magnetic circuit can be advantageously used for this purpose a reed relay. If a plurality of switching elements are required for a module, the control of the contacts can be achieved with a common magnetic circuit, ie a relay with a plurality of contacts or, as shown in FIG. 13 with reference to module switch 150, with a plurality of individual relays 151, 152, 153. The advantage lies in the easier procurement: there are only a few reed relays with contacts for currents> 1 A as catalog goods, but these are always only individual contacts.

By designing the magnetic circuit with multiple windings, a relay can also be operated with NO contact 164 in latching circuit, as shown in the module switch 160 in Figure 14. With the increase of the module voltage above a threshold value, the relay pulls over the inrush current I _E through the turn-on winding 162 and the holding current I _H via the holding winding 163 and remains energized. Switching off can take place via the control current I _s in the control winding 161 which is fed in phase opposition to I _E and I _H , which compensates the fields in the magnetic circuit accordingly and causes the armature to drop. The number of turns of the holding winding n _H , closing winding n _E and control winding n _s are to be interpreted accordingly: n _H <n _E <n _s (1)

FIG. 15 shows a module switch 170, in which the actual switching element is formed by a Darlington transistor 173 (BDV65). In series with the emitter of the Darlington transistor 173, an emitter resistor 174 (0.1 Ω) is connected. The resistor 175 (1.2 kD) causes the transistor 173 to become conductive when the make contact 176 of a relay is open in the ground state. In the operating state, the make contact 176 is closed, and diverts the current supplied by the resistor 175 to a potential that is still below the emitter potential of the transistor 173 due to the resistor 174, so that the transistor 173 is non-conductive.

Emitter resistor 174 generally serves to limit current. When using a plurality of parallel-connected transistors instead of transistor 173, a characteristic shear can be achieved via a plurality of emitter resistors. With the design of the emitter resistor 174, the required for self-supply of the module switch voltage (about 1 -3V) can be further determined.

This solution is simple and inexpensive and works over a wide temperature range. It comes with cheap, very well available components. The switching capacity is kept away from the relay. The contact 176 of the relay must even with very powerful solar modules only a few mA control current derived. When using a silicon npn transistor instead of the Darlington transistor and replacing the resistor 174 by a conductor (0 Ω) can be module voltages in the short circuit case of less than 0.8 V / module reach. This can then be achieved in systems 5 with very high numbers of modules in a string harmless string voltages. In addition, the power transistor is less warm and it may be possible to dispense with additional cooling.

FIG. 16 shows a module switch 180, in which the electrical isolation between control input 1 1 1 and switching element is achieved by an optocoupler 186. The

As in FIG. 15, a switching element consists of a Darlington transistor 173 and a series resistor 174. Between the phototransistor of the optocoupler 186 and the Darlington transistor 173 there is an inverting driver stage comprising a pnp transistor 181 (KF517B) and the resistors 182 (18 kD) and 183 (82 kD) switched. In the ground state, the phototransistor of the opto-coupler 186 provides no

15 electricity. Therefore, the current via the resistor 183 turns on the transistor 181, which in turn turns on the transistor 173.

FIG. 17 shows a module switch 190, in which a Schmitt trigger as a threshold value switch is installed between the phototransistor of the opto-coupler 186 and the base of the transistor 181. The components 173, 174, 181, 182 and 186 and their 20 functions have already been explained in connection with FIG. 16. The supply voltage of the threshold switch is stabilized by means of the LED 203 (VQA13) and the resistor 202. The LED of type VQA13 hardly lights up at a current of approx. 2 mA (= 40 V / 20 kQ).

NPN transistors 197 and 198 (both SC237D) together with resistors 25201 (470Ω), 192 (8.2kD) and 193 (22kD) form a differential amplifier with one output at the collector of transistor 198, an inverted output at the collector of the transistor 197, a non-inverting input at the base of the transistor 197, and an inverting input at the base of the transistor 198. The resistor 195 (8.2 kD) provides a positive feedback and thus a switching hysteresis, 30 the is typical for a Schmitt trigger. The phototransistor, opto-coupler 186, together with the resistors 191 (27 kD) and 199 (100 kD), generates the input signal to the Schmitt trigger. The resistor 200 (100 kD) together with the resistor 195 set the operating point for the transistor 198. Resistor 194 (4.7kD) limits the current to the base of transistor 181. Of the Capacitor 196 (100 nF) suppresses high frequency noise at the control input and prevents too fast switching of the Schmitt trigger.

Instead of the resistors 201 and 202 and power sources can be used.

FIG. 18 shows a module switch 210 similar to the module switch 190 of FIG. 17, but with the phototransistor of the opto-coupler 186 replacing the transistor 197 of the Schmitt trigger. Resistors 212 (4.7kD), 213 (82Ω), 214 (1kD), 215 (4.7kD), 220 (39kD), 221 (270Ω), and 222 (4.7kD) in the module switch 210 correspond in their function to the resistors 192, 193, 194, 195, 200, 201 and 202 in the module switch 10 190, but have slightly different resistance values. Via the diodes 224 and 225, the base potential of optocoupler 186 is defined. The capacitor 223 (4.7 F) stabilizes the operating voltage for the Schmitt trigger in addition to the LED 203.

In the embodiments in FIGS. 16 to 18, 22 and 25, the optocouplers 15 can be effectively divided by fiber optic cables. The LED can then be accommodated in the control signal source 96 instead of in the optocoupler. The control signal is then transmitted to the controls 29 via one or more optical fibers. The controls then have an optical control input at which the electrical power is typically converted into electrical current by a phototransistor or photodiode.

FIG. 19 shows a module switch 230 in which a normally-conducting p-channel MOSFET (metal oxide semiconductor field effect transistor), which is also referred to as a PMOS depletion type, is used as the switching element. If at the control input 1 1 1 a sufficiently high AC voltage is applied, is via the transformer 237th

25 and the bridge rectifier 235 positively bias the gate of the PMOS 231 with respect to the source of the PMOS 231, so that when the bias voltage is sufficiently high, the PMOS 231 eventually turns off, so that the module switch 230 is in the operating state. The two capacitors 238 and 236 together with the corresponding windings of the transformer 237 resonant circuits. This will be a

30 frequency range for the control input 1 1 1 defined. Frequency components outside the frequency range are strongly attenuated. The frequency range can be placed in an area of the frequency spectrum where there is usually little interference. Therefore, the range around the line frequency of 50 or 60 Hz is around Frequency range for the control input 1 1 1 unsuitable. In addition, the width of the frequency range and thus the sensitivity to interference can be reduced by a high quality of the resonant circuits. The capacitor 234 smoothes the pulsating DC voltage supplied from the bridge rectifier 235. Zener diode 233 and resistor 232 (18kΩ) form a voltage divider, with the blocking voltage of the zener diode acting as a threshold voltage that must be exceeded in order for any significant source-to-gate voltage across resistor 232 to drop. The zener diode 233 is optional.

The amount of gate-to-source voltage required to completely block the PMOS 231 is a few volts, often more than 5V. With the driving of the PMOS via a voltage source, which is essentially formed by the transformer 237, the bridge rectifier 235 and the capacitor 234, the full modulation range of the MOSFET can be used.

The resistor 239 in the drain circuit of the MOSFET 231 provides for a minimum voltage drop at the switching output and can be advantageously replaced by one or more diodes in the flow direction. The resistor 239 is not necessary in FIGS. 19, 20 and 21.

FIG. 20 shows a similar module switch 250, in which, in contrast to the module switch 230, the electrical isolation between control input 1 1 1 and switching element is realized by the two capacitors 256 and 257.

FIG. 21 shows a similar module switch 270, in which the blocking voltage for the PMOS 231 is generated by a DC / DC converter 271. The DC / DC converter 271 must also provide the galvanic isolation.

As shown in FIG. 22, in a similar module switch 280, a normally-off n-channel MOSFET 281 may be substituted for the normally-conductive PMOS 231. However, the problem is that the voltage for conducting a typical n-channel MOSFET must be> 5V. You can not win directly from the string 1 15, because the power would be too high. In addition, then the total voltage in the system in the ground state is too high. The problem of too high a voltage in the ground state can be solved by using a DC-DC converter 286 with a low input voltage of <2 V on its secondary side to completely drive through the n-channel MOSFETs required gate-source voltage provides. The treatment of the control signal then takes place as in the bipolar transistor (see Fig. 15 to 18), possibly even with level conversion. The Schmitt trigger from the components 186, 212, 213, 215 and 220, 221, 223 to 225 has already been explained in connection with FIG. The voltage divider of resistor 283 (2.2k) and zener diode 284 (SZ600) limits the voltage on the primary side of DC-DC converter 286. Capacitor 285 (4.7F) stabilizes the voltage on the primary side of the DC DC converter 286.

The secondary voltage supplied by the DC-DC converter 286 can also be used to operate a radio receiver, for example for Bluetooth, ZigBee, WLAN, RFID. This simplifies the installation because the solar cables do not need to contain signal conductors.

It is known in the prior art that with symmetrical signal transmission signals can be transmitted disturbance-tolerant even with longer transmission paths. Since, in the topology shown in FIG. 7, the electrical connections 97 for the control signal extend over a large area of the photovoltaic generator 92, the coupling of interference signals is correspondingly large. Therefore, a topology 300 is shown in FIG. 23, in which two control signal sources 301 and 302 supply two control loops 305 and 306 with two out-of-phase control signals. The solar modules 304 have control elements 309 each with a four-pole control input with a two-pole control input 31 1 and a two-pole control input 312. The currents through the two control inputs 31 1 and 312 are added. By virtue of the fact that the positive input of the control input 31 1 in FIG. 23 is at the bottom and the positive input of the control input 312 in FIG. 23 above, the antiphase control signals are added in terms of magnitude and in-phase disturbances in the two control loops 305 and 306 are subtracted from one another, so that in-phase Erase faults.

As a rule, the lines of the two control loops 305 and 306 are twisted, so that the area enclosed by the two control loops is as similar and equal as possible, so that alternating fields actually couple as equally as possible in both control loops.

The topology 300 shown in FIG. 23 can be simplified in that, for example, the two lower control inputs 313 of the control element 309 shown at the bottom in FIG. 23 are conductively connected and a single one Control signal source is used, which fed via the lines shown in Figure 23 above the loops 305 and 306 in Fig. 23 at the top dargestellen impulse inputs 314. The lines of loops 305 and 306 shown below in FIG. 23 may be dispensed with. This results in a single, n-shaped loop that 5 includes only a very small area and thus collects relatively small interference, with twisted lines individual areas provide positive and negative contributions that largely compensate.

FIG. 24 shows a module switch 320 having a control input 312 and a control input 31 1. The addition of the two currents through the two control inputs

10 312 and 31 1 takes place in transformer 321. It is important that the transformer 321 has two galvanically isolated primary coils. Although the transformer 321 also has two galvanically isolated coils on the secondary side, a secondary coil would be sufficient. The capacitors 322 and 323 together with their primary winding resonant circuits. The further circuit with the components 1 15, 231

15 to 236 and 239 has already been described with reference to FIG.

Figure 25 shows a module switch 340, which also has two control inputs 31 1 and 312. The control inputs 31 1 and 312 are connected to a light-emitting diode of the optocouplers 341 and 342 (MB104C). These LEDs are protected by the diodes 343 and 344 (SAY17) against reverse polarity. The two

20 phototransistors of the two optocouplers 341 and 342 are connected in series.

This achieves an AND operation instead of an addition between the two control signals. Only when both control signals applied to the control inputs 31 1 and 312, both phototransistors are conductive. On the other hand, the two control signal sources 301 and 302 do not supply power but are in the control loops 305

25 and 306 coupled strong in-phase noise, at best one of the phototransistors is conductive, so that the module switch remains in harmless ground state.

The other components 1 15, 173, 174, 181, 182, 191 to 195 and 197 to 203 have already been explained with reference to FIG. 17.

The capacitor 345 corresponds to the capacitor 196 in FIG. 17, but has been selected ten times as large, namely 1 F. If the two control signal sources 301 and 302 supply a control current and at the same time strong in-phase interference signals are coupled into the two control loops 305 at 306, it may happen that one of the two phototransistors becomes temporarily non-conductive. On the other hand, since it is necessary to prevent the transistor 173 from being turned off and on too many times because a lot of power is turned on in the transistor 173 at power-off, the low-pass filter becomes the capacitor 345 and the resistor 199 having a larger time constant of 100 ms provided. As a result, even disturbances from the railway network with a frequency of 16 2/3 Hz and certainly all higher-frequency disturbances, for example, from the power grid are significantly attenuated.

Various combinations of control and switch element are conceivable. Specified circuit variants are only examples. The module switches or parts thereof can also be designed as an integrated circuit.

In the case of a multichannel assembly for multi-string modules, active components of the same function may also be integrated in a common housing, such as e.g. Transistor arrays, multiple optocouplers, relays with multiple windings and / or switching contacts. When using module switches in several individual strings within a module, the module switches are galvanically isolated from each other.

The resistors 133, 174, 239 and 282 serve to maintain a minimum voltage drop for self-voltage supply and may also be outside the junction box, because the converted by the resistance power loss can be quite large. These highly stressed resistors can advantageously be accommodated on the module surface, for example by vapor deposition

FIG. 26 shows a solar cable 360 according to the invention, which is particularly well suited for the connection between the individual solar modules 94 and the solar modules 94 and the bus bars 8 and 9 (cf. FIG. 7). The solar cable 360 has a total of six energy conductors 361, each energy conductor having its own wire wrapper 362. Each of the solar modules 94 may therefore have a maximum of six partial strings. Furthermore, the solar cable has a signal conductor 363 for the serial connection of the control inputs of the control elements 29. The signal conductor 363 also has its own wire sheath 364 and has a smaller cross-section than the energy conductors 361. The wire sheaths 362 and 364 are embedded in a cable sheath 365. The cross section of the cable sheath 365 is circular, because you can seal a circular cross section particularly well against rainwater. FIG. 27 shows another solar cable 370 according to the invention with three energy conductors 371 and four signal conductors 373. Both the energy conductors 371 and the signal conductors 373 are surrounded by wire sheathings 372 and 374, respectively. The cable sheath 375 again has a circular cross-section. This solar cable is suitable for solar modules with up to three substrings, symmetrical control signals (see Figure 23) and two display outputs (see Figure 1 1).

FIG. 28 shows a further solar module 400 according to the invention. As in the case of conventional solar modules, a glass pane 401 is located on the side facing the sun. Underneath is a continuous EVA foil 402. Underneath are the solar cells 403 in a cut EVA foil 404. Underneath is a backside insulation 405, which consists for example of polyvinyl fluoride (Tedlar). Below this is according to the invention a metal rear wall 406, which may additionally have cooling fins 407. The metal back wall 406 may be made of aluminum, for example. A frame 408 holds the various layers of the solar module 400 together. The frame 408 is usually made of aluminum.

Should an arc be formed in the solar module 400, it is unlikely that liquid metal drips through the metal backwall, for example, onto underlying roof tiles, roof battens, rafters or grass and causes a fire. By cooling the solar cells 403, the cooling fins 407 improve the efficiency of the solar cells 403. Instead of the cooling fins 407, the solar module 400 could also be installed in a thermal solar collector and cooled by the liquid in the solar collector.

The invention has been explained in detail above with reference to preferred embodiments. However, it will be apparent to those skilled in the art that various modifications and changes can be made without departing from the spirit of the invention. Therefore, the scope of protection is defined by the following claims and their equivalents. LIST OF REFERENCE NUMBERS

1 photovoltaic system

2 photovoltaic generator

3 inverters

5 4 solar modules

5 string

6 series diode

7 fuse

8, 9 busbar

10 1 1 solar cells

14 solar module

15 partial string

17 connection box

18 bypass diode

15 21 solar cells

22 solar cell array

23 switching element

24 solar module

25 partial string

20 26 series diodes

27 Module junction box

28 bypass diode

29 control

30 plus connection

25 31 negative connection

32 taps

33 plussolar cable

34, 35 minus solar cable

36 electrical conductors

30 38 chamber

41 characteristic

42, 43, 44 characteristics

44 solar module

Point of maximum power stable working point 51 characteristic

55 point maximum power

56 stable operating point

63 switching element

5 64 solar module

65 symbols for solar modules

74 solar module

75 partial string

81 photovoltaic system

10 82 photovoltaic generator

84 solar module

86 series diode

87 fuse

88, 89 multipolar contact point

15 91 Photovoltaic system

92 photovoltaic generator

94 solar module

95 emergency switch

96 control signal source

20 97 electrical connections 98, 99 line

101 photovoltaic system

102 Photovoltaic generator 108 Busbars

25 1 10 general module switches

1 1 1 control input

1 12 signal receiving circuit

1 13 switching element

1 14 driver stage

30 1 15 string

1 16 switching output

1 17 indicator

120 module switch

122 control

35 123 normally closed contact

126 series diode 127 Display element

131 relay coil

32 diode

133 shunt resistance

5 134 LED

136 zener diode

37 series resistance

138 LED

140 module switch

10 141, 142 Optocouplers

143, 144 Display output

147 module switch

150 module switches

151, 152, 153 single relays

15 161 control winding

162 switch-on winding

164 NO contact

170 module switch

173 Darlington transistor

20 174 emitter resistance

175 resistance

180 module switches

181 pnp transistor

182, 183 resistance

25 186 optocouplers

190 module switch

191, 192, 193, 194, 195, 199, 200, 201, 202 resistance

197, 198 transistor

203 LED

30 210 module switch

212, 213, 214, 215, 220, 221, 222 resistance

223 capacitor

224, 225 diodes

230 module switch

35 231 PMOS

232, 239 resistance 233 zener diode

234, 235, 236, 238, 256, 257 capacitor

235 bridge rectifier

237 transformer

5 250, 270 module switch

271 DC / DC converters

280 module switch

286 DC-DC converters

282, 283 resistance

10 284 zener diode

285 capacitor

300 topology

301, 302 control signal sources

304 solar module

15 305, 306 control loops

309 control

31 1, 312, 313, 314 control input

320 module switches

321 transformer

20 322, 323 capacitors

340 module switch

341, 342 optocouplers

343, 344 diodes

345 capacitor

25 360 solar cables

361 energy manager

362, 364 wire wrap

363 signal conductor

365 cable sheath

30 370 solar cables

371 energy manager

373 signal conductor

372, 374 veining

375 cable sheath

35 400 solar module

401 glass pane 402 EVA film

403 solar cells

404 EVA film

405 back insulation 406 metal back wall

407 cooling fins

408 frame

Claims

claims

1 . Modular switch for a string (25) of a solar module (24, 44, 64, 74, 84, 94), the string (25) comprising a plurality of solar cells (21) connected in series and an anode terminal and a cathode terminal , with: a control input (1 1 1); and a switching output (16) having a plus terminal and a minus terminal, the plus terminal being adapted to be electrically connected to the anode terminal and the minus terminal being intended to be electrically connected to the cathode terminal, characterized by a series diode (26, 126), which is connected in series with the switching output, so that the anode of the series diode is connected to the positive terminal and the negative terminal and the cathode of the series diode with solar cables (33, 34, 35) are connectable for installation of the solar module in a solar system, or the cathode of the series diode (26, 126) is connected to the negative terminal and the positive terminal and the anode of the series diode (26, 126) can be connected to solar cables for installation of the solar module in a solar system.

2. Module switch according to claim 1, characterized in that the positive terminal and the negative terminal are high-resistance or electrically isolated when the control input (1 1 1) a signal above a threshold and the two electrical terminals of the switching output (1 16) connected to each other with low resistance are when the control input (1 1 1) has a signal below the threshold value.

3. A module switch for a string of a solar module, the string comprising a plurality of solar cells (21) connected in series and an anode terminal and a cathode terminal, comprising: a control input (1 1 1); and a switching output (1 16) having a positive terminal and a negative terminal, the positive terminal being provided for electrically connecting with Anodenanschluss to be connected and the negative terminal is intended to be electrically connected to the cathode terminal, characterized in that the positive terminal and the negative terminal are high-resistance or electrically isolated 5, when the control input (1 1 1) is applied a signal above a threshold and the two electrical connections of the switching output (1 16) are connected to each other with low resistance, if at the control input (1 1 1), a signal below the threshold is applied.

4. Module switch according to one of claims 1 to 3, characterized in that the control input 10 (1 1 1) two electrical connections and the module switch further comprises an antenna which is connected to the two electrical terminals of the control input (1 1 1).

5. Module switch according to one of claims 1 to 3, characterized in that the control input (1 1 1) and the switching output (1 16) from each other

15 electrically isolated (131, 123, 151, 152, 153, 161, 162, 163, 164, 176, 186, 237;

256, 257; 271) are.

6. Module switch according to one of the preceding claims, characterized in that the module switch further comprises one or more display elements (134, 138) which the high-impedance and / or

20 indicate low-resistance state.

7. Module switch according to one of the preceding claims, characterized in that the module switch when switching from low-impedance to high-impedance state and vice versa has a hysteresis.

8. Module switch according to one of the preceding claims, characterized in that the module switch has two control inputs (31 1, 312) for 2 antiphase control signals.

9. Module switch according to one of the preceding claims, characterized in that the switching output (1 16) has two contact points on each of the two electrical connections.

30 10. Solar module with: a string (25, 65, 75) comprising a plurality of solar cells (21) connected in series and comprising an anode terminal and a cathode terminal; a module switch with: a control input (1 1 1); and a switching output (16) having a plus terminal and a minus terminal, the plus terminal being electrically connected to the anode terminal and the minus terminal electrically connected to the cathode terminal, characterized by a series diode (26, 126) connected in series with the switching output is, so that the anode of the series diode is connected to the positive terminal and the negative terminal and the cathode of the series diode (26, 126) with solar cables (33, 34, 35) for installing the solar module in a solar system can be connected or that the cathode of the series diode (26, 126) is connected to the negative terminal and the positive terminal and the anode of the series diode (26, 126) with solar cables (33, 34, 35) are connectable for installation of the solar module in a solar system.

1 1. Solar module (24, 64, 74, 84, 94) comprising: at least two strings (25, 65, 75), each string comprising a plurality of solar cells (21) connected in series, characterized in that each string faces the other strings is galvanically isolated.

12. Solar module according to claim 1 1, characterized in that the solar module further comprises a module junction box (27), wherein there are two contact points in the module junction box for each string.

13. Solar module in particular according to claim 11, characterized in that the solar module has at least one string (25, 65, 75), wherein the solar module comprises a series diode (26), for example a Schottky diode, which is connected in series to the solar cells of the string, so that the voltage supplied by the solar cells polt the series diode in the flow direction.

14. Solar module (24, 64, 74, 84, 94) according to any one of claims 1 1 to 13, characterized in that for the positive connection of the string, a chamber (69) in the

5 module connection box (27) and for the negative connection of the string another chamber (69) in the module junction box (27) is provided.

15. Solar module in particular according to one of claims 1 1 to 14, characterized in that the rear wall (406) of the solar module (400) is made of a metallic material, such as aluminum.

10 16. Solar module according to claim 15, characterized in that the rear wall of the solar module is provided with a profile (407).

17. Solar module, in particular according to one of claims 1 1 to 16, wherein the solar module has at least one string (25, 65, 75) having a plurality of solar cells (21) connected in series and an anode terminal and a 15 A cathode terminal, characterized by: a module switch according to any one of claims 1 to 9, wherein the positive terminal is electrically connected to the anode terminal and the negative terminal is electrically connected to the cathode terminal.

20 18. solar cable (33,34,35), characterized in that the solar cable comprises a plurality of mutually insulated, electrical conductor, wherein the wire sheath of the electrical conductor consists of an arc-inhibiting material.

19. Solar cable according to claim 18, characterized in that one of the plurality of electrical conductors has a smaller cross section than the one or more electrical conductors.

20. busbar (8, 9) for solar systems, characterized in that the busbar multi-pole contact points (88, 89) for solar cable (33, 34, 35) having a plurality of electrical conductors.

21. A device (96) for generating a control signal for solar modules (94) according to claim 14, wherein the solar modules (94) are part of a photovoltaic system (91), comprising: an output for outputting a signal to the module switches of the solar modules; an input for connection to busbars (8, 9) of the photovoltaic system, the device being intended and suitable for generating a signal from the low voltage at the collector ends (8, 9) when the module switches of the solar modules are in the low-resistance state to produce at the output, which switches the module switch in the high-impedance state, and the device is not destroyed by the higher voltage at the busbars when the module switches are in high-impedance state.

22. Apparatus according to claim 21, characterized in that the device comprises a switch (95) with two positions, wherein the device is determined and adapted to generate in the first position of the switch, a signal at the output, the module switches of the solar modules in switches the high-resistance state when the module switches are in the low-resistance state or when the module switches are in the high-resistance state, when the module switches are in the high-resistance state and no signal is generated at the output in the second position of the switch.

23. Device according to one of claims 21 or 22, characterized in that it is the device to an inverter (3) or charge controller.