PHOTOVOLTAIC MODULE AND CONNECTION ARRANGEMENT FOR A PHOTOVOLTAIC MODULE

Abstract

A connection assembly for a photovoltaic module includes at least one cell assembly which is externally contactable to at least two contacts. The connection assembly includes at least one bypass diode, which is arranged externally of the at least one cell assembly and connected in parallel to the at least one cell assembly. The connection assembly is characterized in that the connection assembly has at least one plug receptacle into which the bypass diode can be plugged in with plug contacts. A photovoltaic module with such a connection assembly is also provided.

Claims

1. A connection assembly for a photovoltaic module, comprising at least one cell assembly which is externally contactable to at least two contacts and having at least one bypass diode which is arranged externally of the at least one cell assembly and connected in parallel with said at least one cell assembly; and at least one plug receptacle including plug contacts for a plug in connection with said bypass diode can be plugged in with plug contacts.

2. The connection assembly as defined in claim 1, and further comprising at least one connection box.

3. The connection assembly as defined in claim 2, and further comprising at least one power cable for the photovoltaic module and at least one connection cable which leads to a further connection box connected to at the at least one connection box.

4. The connection assembly as defined in claim 3, wherein said at least one connection box includes a contact element connected with contacts of the photovoltaic module.

5. The connection assembly as defined in claim 3, wherein said connection box has an isolation-penetrating contact for connection at least one of said power cable and said connection cable.

6. The connection assembly as defined in claim 3, wherein said at least one connection box has at least one plug receptacle into which said at least one bypass diode is plugged.

7. The connection assembly as defined in claim 6, and further comprising a plug holder counter sunk in at least one of said connection cables, said plug holder including at least one plug receptacle into which at said least one bypass diode is plugged.

8. The connection assembly as defined in claim 1, wherein said at least one bypass diode is received in a housing from which said plug contacts protrude.

9. The connection assembly as defined in claim 8, wherein said at least one bypass diode in said housing is surrounded by a grouting compound.

10. The connection assembly as defined in claim 1, and further comprising a light-emitting diode connected in parallel to said at least one bypass diode.

11. The connection assembly as defined in claim 10, wherein said light-emitting diode is arranged in said housing.

12. A photovoltaic module comprising at least one connection assembly as defined in claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0018] The invention will be explained in greater detail below using an embodiment with the aid of the accompanying figures, in which:

[0019] FIG. 1a is a perspective view of a PV module with a view onto its rear side;

[0020] FIG. 1b is a detailed perspective view of part of a connection assembly of the PV module from FIG. 1a;

[0021] FIG. 1c is a detailed perspective view of a diode assembly of the PV module from FIG. 1a;

[0022] FIG. 2 is a detailed perspective view of part of a connection assembly of the further embodiment of a PV module;

[0023] FIGS. 3a and 3b are perspective views of diode units, respectively, for use with a PV module;

[0024] FIGS. 4a and 4b are perspective views of diode units, respectively, without a housing;

[0025] FIG. 5a is a perspective view of part of a connection assembly of the further embodiment of a PV module with inserted diode units; and

[0026] FIG. 5b shows the connection assembly FIG. 5a with diode units removed.

DETAILED DESCRIPTION

[0027] FIG. 1a shows a PV module 1 in an isometric depiction. The PV module 1 has a frame 2 and the actual module structure, which in the context of this application is also referred to as the layered design or layer stack. Only a rear side 3 of this module structure can be seen in FIG. 1a.

[0028] In the PV module 1, the module structure includes one or more cell assemblies—specifically three in this example—which each have a number of PV cells which cannot be seen individually and which are connected to one another on the rear side 3 at their electrodes via e.g. conductor tracks. The rear side 3 is covered by an isolating layer which is removed at selected locations in order to expose the electrodes or the conductor tracks which connect them and to enable contacting. Alternatively, there can also be connecting lugs or connecting contacts present which are connected to the electrodes or the conductor tracks and which protrude from the isolating layer.

[0029] In the embodiment shown in FIG. 1a, the PV module 1 is contacted at four locations. One connection box 4 in each case is installed, preferably glued on, via the contact locations. Two adjacently located contact locations or connection boxes 4 are allocated to a cell assembly of the PV module. By way of example, a first cell assembly can be contacted via the two left-most of the connection boxes 4, a second cell assembly can be contacted via the two middle connection boxes 4 and a third cell assembly can be contacted via the two right-most connection boxes 4. It should be noted that the number of cell assemblies connected to one another in series in this embodiment, which is three here, is purely by way of example. The connection assembly presented can be employed for any number of cell assemblies connected to one another in series. The individual cell assemblies themselves generally have a number of cells which in turn are interconnected in series and/or in parallel.

[0030] From each of the outer two of the connection boxes 4, a power cable 5 extends outwardly. This power cable 5 is depicted in a shortened manner in the figures. In one embodiment, this power cable 5 is configured to be longer and has at its end in each case a plug connector with which a connection can be made to an adjacent module or a module connection box or the like.

[0031] Between two of the connection boxes 4 in each case there is arranged a connection cable 6 into which a diode assembly 10 is countersunk. The diode assembly 10 is shown merely schematically in FIG. 1a. It includes a plugged bypass diode, not shown, which contacts the two cable sections of the connection cable 6 by its anode or cathode respectively. In the present case, three bypass diodes are each connected antiparallel to each of the three cell assemblies of the PV module 1.

[0032] The connection assembly can preferably be pre-fabricated and pre-installed, so that it need only be fitted onto connection contacts of the PV module 1 during the final mounting of the PV module 1. An adhesive sealing agent with which the connection boxes 4 are glued onto the rear side 3 of the PV module 1 in a sealing manner is preferably used.

[0033] Isolation-penetrating contacts, for example, can be used to connect the power cable 5 or connection cable 6 inside the connection boxes 4. In addition, the power cable 5 can be configured integrally with the corresponding section of the connection cable 6. The power cable 5 and this section of the connection cable 6 are a continuous piece of cable in this case. The same applies to the two sections of the connection cable 6 in the case of the two middle connection boxes 4 depicted in FIG. 1a.

[0034] FIG. 1b shows part of the connection assembly of the PV module 1 from FIG. 1a in greater detail, in an isometric view. The diode assembly 10 includes a plug holder 11, into which the bypass diode can be plugged. The plug holder 11 is represented in an enlarged fashion in FIG. 1c.

[0035] The plug holder 11 includes a plug-in base 111, in which the bypass diode can be plugged into a plug receptacle 113. A sealing cap 112, which can be fitted onto the plug holder 11 with the plugged-in bypass diode and which seals the plug receptacle 113, is undetachably connected to the plug-in base 111 via a flexible bar. Not visible in FIGS. 1b and 1c, contacts which are coupled to the connection cables 6 and contact the plugged-in bypass diode are arranged in the plug-in base 111. The plug receptacle 113 and the plugged-in bypass diode can be formed such that the bypass diode can be plugged in only in one possible orientation, in order to ensure the correct polarity of the plugged-in bypass diode.

[0036] The plug holder 11 or its plug receptacle 123, together with the bypass diode which can be plugged in, offers one simple possibility for exchanging the bypass diode when it has become non-functional due to a thermal and/or electrical overload situation, for example. Due to the simple plugging process, the exchange can also be performed by untrained personnel. In addition, it is possible to remove a bypass diode and easily check that it is functional, which, in the case of a bypass diode installed in the connection assembly, is possible only with more elaborate measuring methods. Furthermore, the bypass diode's ability to be plugged in enables flexible equipping or retrofitting of the connection assembly with bypass diodes of differing quality levels. For example, bypass diodes made of silicon which are initially provided by the manufacturer can be exchanged for actively connected bypass diodes based on MOSFET transistors, in order to minimize losses in the event of shadow.

[0037] FIG. 2 shows part of a connection assembly for a PV module in a further embodiment. The connection assembly in turn has a connection box 4 which is installed on the rear side of the PV module. Two cables, which can be power cables 5 and/or connection cables 6, lead to the connection box 4.

[0038] In this embodiment, a plug receptacle 41 is configured, as part of a diode assembly 10, in the connection box 4. The plug receptacle 41 corresponds to the plug receptacle 113 of the plug holder 11, by a diode unit 12 being able to be plugged in with a bypass diode. In the example from FIG. 2, the diode unit 12 is depicted separately from the connection box 4, i.e. in a state shortly before the plugging-in into the plug receptacle 41, for example.

[0039] The connection box 4 can be positioned over a contact of the PV module so that inside the connection box 4, the contact of the PV module is connected to the bypass diode and also to the power cables 5 or connection cables 6. Alternatively, the shown connection box 4 can only produce a connection between the bypass diode and the shown cables (which in this case are then exclusively connection cables 6). The connection box 4 then, in principle, corresponds to the plug holder 11 of the previous embodiment, with the difference that the connection box 4 is installed on the rear side of the PV module and is not borne by the connection cables 6.

[0040] In the diode unit 12, the bypass diode is arranged in a housing 121 and is connected inside the housing 121 with plug contacts 122 which protrude out of the housing 121. The diode unit 12 shown in FIG. 2 is also depicted in greater detail separately in FIG. 3a. FIG. 3b likewise shows a diode unit 12 with a housing 121 and plug contacts 122, which differs from the example shown in FIGS. 2 and 3a by the shape of its housing 121.

[0041] The housing 121, which is made of an isolating material, serves as a gripping region at which the diode unit 12 can be safely gripped and inserted into the plug receptacle 41 or 113 or pulled out of it. Due to the height of the housing 121, mating contacts which are configured in the connection box 4 or plug-in base 111 of the plug holder 11, and with which the plug contacts 122 come into contact, are recessed so far in a shaft of the plug receptacle 41, 113 that touching is precluded.

[0042] In the housing 121 shown in FIGS. 2 and 3a, recesses which enable the diode unit 12 to be pulled out of the plug receptacle 41 or 113 are introduced laterally. If required, a pliers-type or forceps-type auxiliary tool can be employed for removal. In the housing 121 lower region which points towards the plug contacts 122, there is configured a bead which serves to seal the housing 121 in a shaft of the plug receptacle 41, 113.

[0043] A possible inner design of the diode units 12 from FIGS. 3a and 3b is shown in FIGS. 4a and 4b. The diode units 12 are represented without the housing 121 in FIGS. 4a and 4b.

[0044] The diode unit 12 in each case has one bypass diode 123, which is soldered onto the plug contacts 122 with connection elements. By way of example, the bypass diodes 123 are surface-mounted components. In alternative configurations, leaded bypass diodes whose connection wires are connected to the plug contacts 122, may be used instead.

[0045] The unit made up of the bypass diode 123 and plug contacts 122 is preferably inserted into the housing 121 and grouted with grouting compound. Thus a good transfer of heat from the bypass diode 123 onto the housing 121 is achieved, with the heat being able to be given off easily to the surroundings from this housing due to the large surface of the housing 121 compared to the surface of the bypass diode 123 itself. In one configuration of the diode unit 12, the grouting compound forms the housing 121.

[0046] In contrast to the example in FIG. 4a, the diode unit 12 of the example in FIG. 4b additionally has a light-emitting diode (LED) 124, which is connected in parallel to the bypass diode 123 and is likewise connected to the plug contacts 122. The LED 124 is preferably internally equipped with a series resistor or a series resistor is connected upstream, such that a current flowing through the LED 124 is limited. With a functional bypass diode 123, there is a smaller drop in voltage at the bypass diode 123 when a current flows through the diode unit 12 than is required to light up the LED 124. In contrast, if the bypass diode 123 is faulty such that it also does not take up any flow of current in the flow direction, the drop in voltage at the plug contacts 122 is so great that the LED 124 lights up and thus indicates the defective state of the bypass diode 123. In order to be able to notice the LED 124 from outside, the housing 121 is configured to be transparent at least in this area or is equipped with a transparent viewing window. If a grouting compound is used, this is likewise selected to be transparent or does not cover the LED 124.

[0047] In alternative configurations of the connection assembly, such a light-emitting diode is not positioned in the diode unit 12, but rather inside the plug holder 11 or the connection box 4 into which the diode unit 12 is plugged.

[0048] In a further embodiment, part of a connection assembly of a PV module is depicted in FIGS. 5a and 5b. In this embodiment, an individual connection box 4 is present on the rear side of the PV module, out of which there extend two power cables 5 for the external connection of the PV module.

[0049] The use of a single connection box 4 is employed with PV modules in which all contacts of the various cell assemblies of the PV module are guided out of the PV module, adjacently in one region. The shown connection box 4 covers this region. In the depicted example, three cell assemblies are in turn separately accessible by their end connections, in order to interconnect three bypass diodes parallel to these cell assemblies.

[0050] In a different manner than known from the prior art, in the depicted embodiment the bypass diodes are in turn arranged in pluggable diode units 12, which can be plugged into correspondingly three plug receptacles 41 configured in the connection box 4. FIG. 5a shows the diode units 12 plugged into the plug receptacles 41, and FIG. 5b shows the diode units 12 shortly before or after plugging-in.

[0051] In an alternative configuration, it is also conceivable to employ a comparable connection box into which it is possible to plug bypass diodes which are connected inside the connection box to the cell assembly of the PV module, but with power cables leading to one or more further connection box(s) which are separate therefrom and in which they are connected to the PV module.