JP4578127B2 - Solar cell module and solar power generation apparatus using the same - Google Patents

Description

  The present invention relates to a solar cell module that generates power using solar energy and a solar power generation device using the solar cell module, and in particular, the rated output voltage and current can be changed by the solar cell module alone, and the connected load and installation distance. It is related with the solar power generation device which can switch the output voltage of a solar power generation device according to the above.

  In recent years, with increasing interest in global environmental problems, new energy technology using natural energy has attracted attention. One of them is solar power generation as a power source in research activities in developing countries, remote villages where power transmission is not possible, deserts and undeveloped areas where there is high interest in solar energy-based systems and construction of large power plants. Independent power supply systems using devices are active. The independent power supply system is a simple type that supplies the power generated by the solar power generator directly to a load such as a communication device or a pump. In addition, the power generated in the daytime is stored in a storage battery to stabilize the power supplied to the load or at night. A storage type that can be used for a load during non-power generation such as lighting is common, and this configuration may be rearranged depending on time and circumstances.

  Generally, a solar power generation device uses a solar cell module in which a plurality of solar cell elements are connected and arranged in series or in parallel, or a solar cell array in which a plurality of the solar cell modules are assembled. This is because the rated output voltage of a single solar cell element is approximately 0.45 V for a polycrystalline solar cell element, for example, and in order to obtain a voltage such as 12 V or 24 V, which is a typical DC load rated voltage (for example, a motor). This is because they need to be connected in series, and need to be connected in parallel if the drive current is not sufficient.

  Hereinafter, the structure of the solar cell module manufactured by the laminate type manufacturing method will be described as an example.

  FIG. 10 is a configuration diagram illustrating an example of an embodiment of a solar cell module according to the present invention, FIG. 11 is a configuration diagram schematically illustrating a configuration of a conventional solar power generation device, and FIG. It is a block diagram which shows typically one Example of the switching method of a voltage.

  As shown in FIG. 10, the solar cell module 21 is provided with a light transmission plate 14 such as glass or resin on the light receiving surface, and a large number of solar cell elements 1 are formed on the light transmission plate 14 with EVA resin (Ethylene-Vinyl Acetate). A non-light-receiving surface that is the back surface thereof is laminated with a weathering film 16 such as a Teflon (R) film, PVF (polyvinyl fluoride), or PET (polyethylene terephthalate). As the solar cell element 1, for example, a single crystal, polycrystalline or amorphous material such as a compound semiconductor made of a silicon-based semiconductor or gallium arsenide is used, and is electrically connected in series and / or in parallel with each other. Connected to the back surface of the solar cell module 21, that is, on the weather resistant film 16, is a synthetic resin such as ABS resin or Bonding the junction box 12 which is configured by a Miniumu metal, the output is taken out by the transmission line connected to the terminal for taking out the output power of the solar cell module 21.

  The light transmitting plate 14, the solar cell element 1, and the weather resistant film 16 are attached to the rectangular main body so as to sandwich the frame 11 made of aluminum metal, SUS, or the like around each side, The solar cell module 21 is configured to serve as a fixing portion for installation. Moreover, it is useful also for the objective of the intensity | strength improvement which protects the edge part of the solar cell module 21, and raises the whole intensity | strength. The frame 11 is made of a metal bending material such as iron, stainless steel, or aluminum, or a resin molded product such as extrusion molding or FRP. The frames can be assembled directly by screws or rivets. It is carried out by fixing via an auxiliary member such as a plate or by adhering to a light transmission plate 14 such as glass or resin. Moreover, it is good also as a structure which inserts the light-transmitting board 14 in the integrally molded frame.

  The electrical configuration in the solar cell module 21 made as described above is shown in FIG. The solar cell module 21 is composed of a solar cell panel 31 composed of solar cell elements 1a to 1h and a junction box 12, and the solar cell panel 31 has solar cell elements 1a to 1h connected in series. Assuming that the rated output voltage of one solar cell element is 0.45 V, an output voltage of 3.6 V can be taken out from the terminals (+ pole and −pole) in the junction box 12. The power generated from the solar cell module 21 is supplied to a load 19 such as a motor or lighting or a power storage means 17 such as a battery using a power transmission cable 13. At this time, since the output voltage of the solar cell module 21 is determined by the number of series of solar cell elements, the solar cell module using the number of series of solar cell elements as many as the voltage reaches in order to produce a necessary voltage. Alternatively, as shown in FIG. 12, a plurality of solar cell modules 21 (21a, 21b) are connected in series to obtain a voltage necessary for the device.

  In general, DC loads are often designed on the assumption that they are driven using power storage means such as a battery. Therefore, most of them have a rated input voltage of 12V or 24V. For this reason, the solar cell module also often has a series number of solar cell elements in accordance with this, and the polycrystalline solar cell element has a configuration of 36 series to 72 series.

  By the way, if the generated power of the solar cell module is 50 W, for example, the area of the solar cell module itself is almost the same. Halved. Therefore, if the load is 24V and the current is 2A or less, the use of the 24V solar cell module is smaller and the number of components is smaller than the two 12V solar cell modules used in series. In particular, the more the photovoltaic power generation apparatus that supplies power to a DC-AC inverter or the like having a high voltage (many of 90 V or more), the larger the number of solar cell elements in series, the greater the problem. Furthermore, the current capacity can be increased by configuring a 24V system with a 12V solar cell module, but there is also a problem that the power generation loss becomes worse due to an increase in the number of operations of a mechanism for protecting the overcharge of the storage battery. . Thus, the rated output voltage of the solar cell module used in the photovoltaic power generation apparatus should be that of the output voltage and output current that match the load to be connected.

Therefore, a method has been proposed in which the output of the solar cell modules constituting the solar cell array can be switched in series and in parallel so that the output voltage from the solar cell array is optimized and the power generation loss is reduced. . (For example, see Patent Document 1)
In addition, there has been proposed one in which the connection wiring between the positive electrode and the negative electrode of the terminal block in the junction box does not cross so that a short circuit or the like does not occur when wiring a plurality of solar cell modules in series (for example, Patent Document 2).
Japanese Unexamined Patent Publication No. 2000-89841 Japanese Patent Laid-Open No. 2003-152111

  However, in the photovoltaic power generation apparatus as in the above-described conventional technology, the load to be used and the rated output power (rated output voltage and rated output current) of the solar cell module are selected according to the installation area and the number of used solar cell modules (array). In addition, it affects the number of man-hours for the construction and cannot be ignored. In addition, there is a problem that a lot of loads are required in transportation and it takes time to carry.

  Furthermore, when installing a solar power generation device in a remote village or the like, for example, it is necessary to make sure that the system is 12V or 24V. There is a delay in work and construction time, and thorough design information and product management are required. For example, in a well water pumping system installed with support for developing countries, for example, even if an alternative pump is prepared due to a failure of a pumping pump of 24V specification, only a pump of 12V specification can be obtained and repaired. There is a limit that cannot be dealt with on the solar power generation side, such as when it cannot be used or until it arrives after importing a 24V specification pump. In this case, if it is a solar power generation device designed with a 12V solar cell module, there is a high possibility that it can be applied to a 12V specification pump system. As such, there is no change in being over-spec and having other disadvantages.

  Moreover, although the installation location of a solar cell module is various, what can be said in common is that the area and the place which can receive sunlight for sufficient time are required according to power generation capacity. However, the place where these conditions can be satisfied does not always match the place where the load is used. In many cases, a power cable of about several tens to hundreds of meters is placed between the solar cell module and the load. Power loss at the time (particularly voltage drop due to the resistance component of the transmission cable) becomes a problem.

  On the other hand, if the breakdown voltage is reduced due to the failure of some solar cell modules in the solar power generation device, check the breakdown voltage of the entire solar cell array and confirm that a breakdown voltage failure has occurred. In order to specify the solar cell module, it has been necessary to confirm the dielectric strength while disconnecting the output wiring of each solar cell module, which requires a great deal of labor.

  And in the system that makes the arbitrary output voltage by switching the connection of the solar cell array, the connection wiring between the solar cell modules becomes complicated, not only the management and supervision of workers with advanced wiring knowledge is necessary, There is a problem that the work of disconnecting the wiring in the case where an insulation withstand voltage failure occurs becomes more complicated.

  In view of the above, the object of the present invention is to respond to changes in the usage load without increasing the installation area and construction man-hours, and to easily change during the load (including short-term changes). An object of the present invention is to provide a solar cell module and a solar power generation device using the solar cell module.

  Another object of the present invention is to provide a solar power generation apparatus that reduces output power loss during power transmission by switching output power according to power loss due to power transmission distance.

  Still another object of the present invention is to enable measurement of dielectric strength in units of solar cell modules without removing wiring.

  To achieve the above object, the solar cell module of the present invention has two solar cell strings in which a plurality of solar cell elements are connected in series, and the positive output terminal block of the one solar cell string is a solar cell. A solar cell module having a positive output terminal of the module and a negative output terminal block of the other solar cell string being a negative output terminal of the solar cell module, the solar cell module having a positive of the one solar cell string An output terminal block, a positive output terminal block of the other solar cell string, a negative output terminal block of the one solar cell string, a negative output terminal block of the other solar cell string, and a negative output terminal of the one solar cell string And the positive output terminal block of the other solar cell string are close to each other A manner electrically arranged in a non-conducting state, further characterized in that the formation of the screw hole so as to be electrically conductive by receiving the conductivity of the screw-type connectors to the output terminal block close these together.

  Another solar cell module of the present invention is for receiving a conductive screw-type connector formed on the negative output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string. A conductive screw-type connector is screwed into the screw hole, and the two solar cell strings are connected in series.

  Another solar cell module of the present invention is for receiving a conductive screw-type connector formed on the positive output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string. Conductive screws in screw holes and screw holes for receiving conductive connectors formed in the negative output terminal block of the one solar cell string and the negative output terminal block of the other solar cell string, respectively. A type connector is screwed and the two solar cell strings are connected in parallel.

  Another solar cell module of the present invention is for receiving a conductive screw-type connector formed on the positive output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string. A screw hole for receiving a conductive screw-type connector formed on the negative output terminal block of the one solar cell string and the negative output terminal block of the other solar cell string; Screw the conductive screw type connectors into the screw holes for receiving the conductive screw type connectors formed on the negative output terminal block of the solar cell string and the positive output terminal block of the other solar cell string. And the two solar cell string outputs are short-circuited.

  Moreover, the solar power generation device of this invention uses the solar cell module in any one of Claim 1 thru | or 6.

According to the solar cell module of the present invention, the positive side output terminals of the plurality of arranged solar cell elements are two solar cell strings connected in series, the solar cell module on the plus output terminal block hand of the solar cell string and then, the negative output terminal block of another side of the solar cell string of the solar cell module to a solar cell module with a minus side output terminal, of the one solar cell string in the solar cell module positive output terminal block and the other The positive output terminal block of the solar cell string, the negative output terminal block of the one solar cell string, the negative output terminal block of the other solar cell string, the negative output terminal block of the one solar cell string, and the other solar cell Make sure that the positive output terminal block of the string is close to each other and is in an electrically non-conductive state. And location, further by forming a screw hole to allow electrical conduction accept conductive screw-type connectors to the output terminal block close these together, the negative output terminal block and the other of the one solar cell string The positive output terminal block of the solar cell string is electrically connected, the one solar cell string and the other solar cell string can be connected in series, and the positive output terminal block of the one solar cell string and the The positive output terminal block of the other solar cell string is electrically connected, the negative output terminal block of the one solar cell string is electrically connected to the negative output terminal block of the other solar cell string, and the one solar cell string is electrically connected. since the cell string and said other of the solar cell string can enable parallel connection, to change the output voltage Since in ability, correspondence easily to the load rated voltage of which is connected.

  In addition, when the connectors are inserted between all output terminal blocks, the output of the solar cell module is in a short-circuited state, and a jumper wire is additionally connected to the output terminal block so that all terminals have the same potential as before. It is possible to simplify the man-hour and perform a dielectric strength test of the solar cell module. In addition, when a plurality of other solar cell modules are connected, it is not necessary to remove the wiring of all the solar cell modules and perform the dielectric strength test for each one, and all the solar cells other than the dielectric strength test are performed. By simply removing the connector of the battery module, it is possible to inspect the insulation withstand voltage of only a specific solar cell module, so that the number of work steps can be greatly reduced and wiring errors during rewiring are less likely to occur.

  Furthermore, since the generated power is not output to the outside from the solar cell module until the connector is inserted, there is no need to separate the wiring when replacing the externally connected power storage means or load, system maintenance, etc. Power transmission can be easily stopped.

  Also, if the externally connected load becomes unusable due to a failure, etc., even if the rated input voltage of the substitute is different, there is no need to replace the wiring of the transmission cable. This can be dealt with only by changing the insertion position, and there are no problems such as wiring rearrangement and insufficient length of the power transmission cable. Furthermore, since the voltage switching is performed by a single solar cell module, there is no restriction due to the odd number / even number of solar cell modules.

  Moreover, since it respond | corresponds to lowering | hanging the voltage of a solar power generation device by voltage switching, the applicability by the change of the rated voltage of a load does not arise.

  In addition, when the influence of power loss due to the length of the transmission cable that transmits the output of the solar cell module is large, the voltage is increased to reduce power generation loss, and in normal times, the voltage setting is restored to maximize the power generation power. At the same time, it is possible to use the device without being restricted by the rated voltage of the device.

  In addition, when there is a limit to the installable area, such as a residential solar power generation device, the output voltage setting is set to a high voltage using the area of the solar cell module that cannot be mounted because the voltage does not reach the specified value due to insufficient number of series. The voltage can be set to the specified value on the side of the roof so that it can be placed on the roof, thereby improving the ratio of the power generation area to the roof area and increasing the power generation amount of the entire photovoltaic power generation apparatus.

  According to another solar cell module of the present invention, the conductive screw-type connector formed on the negative output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string is received. By screwing a conductive screw-type connector into the screw hole for connecting the two solar cell strings in series, an output voltage twice that of the solar cell string can be easily obtained.

  According to another solar cell module of the present invention, the conductive screw type connector formed on the positive output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string is received. And a screw hole for receiving a conductive connector formed on the negative output terminal block of the one solar cell string and the negative output terminal block of the other solar cell string, respectively. The screw type connector is screwed and the two solar cell strings are connected in parallel, so that an output current twice that of the solar cell string can be easily obtained.

  Furthermore, according to another solar cell module of the present invention, a conductive screw-type connector formed on the positive output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string is received. A screw hole for receiving a conductive screw-type connector formed on the negative output terminal block of the one solar cell string and the negative output terminal block of the other solar cell string, and Conductive screw type connectors in the screw holes for receiving the conductive screw type connectors formed on the negative output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string, respectively. And the insulation characteristics of the solar cell module can be measured by short-circuiting the two solar cell string outputs.

  Moreover, the solar cell power generator of the present invention can easily cope with a change in load specifications and the like by using the solar cell module according to any one of claims 1 to 6.

  In addition, when performing the dielectric strength test, the number of work steps is greatly reduced, and wiring errors during rewiring are less likely to occur.

  Hereinafter, as an example of an embodiment of the present invention, a solar power generation apparatus using a 12V system or 24V system DC load will be described as an example, and a detailed description will be given based on the drawings schematically illustrated.

  FIG. 1 is a plan view showing a component configuration and a combined state of an example of an embodiment of a solar cell module of the present invention.

  As shown in FIG. 1, a solar cell module 20 includes a first solar cell string 2 (a solar cell string in which solar cell elements are linearly connected in series or in parallel) and a second solar cell string 3. An output terminal block 4 (4a to 4a to 4a) provided in the terminal box is arranged on a single translucent substrate so that the output of the first solar cell string 2 and the output of the second solar cell string 3 are arranged in a plane. 4d). The first solar cell string 2 and the second solar cell string 3 have a value of the output voltage (solar cell element so that the generated power does not flow backward and damage the solar cell element regardless of whether the series or parallel connection is made. The same number or within a few volts.

  In this example, the positive pole of the first solar cell string 2 is the output terminal block 4a, the negative pole of the first solar cell string 2 is the output terminal block 4c, and the positive pole of the second solar cell string 3 is the output terminal block 4b. Description will be made assuming that the negative electrode of the second solar cell string 3 is connected to the output terminal block 4d.

  Moreover, since the manufacturing method as the solar cell module 20 is the same as that of the conventional structure, it shall not be described in particular. Between the terminals of the output terminal block 4, a first gap 8b is provided between the first gaps 8a, 4b-4c between the second gaps 9, 4c-4d between 4a-4b. 8a, 8c), by inserting the connector 6 (6a, 6b), the output terminal blocks 4a, 4b, 4c, 4d are electrically connected, and the first solar cell string 2 and the second solar cell string 3 are connected to each other. Connected in parallel. On the other hand, by inserting the connector 5 only into the second gap 9, the output terminal blocks 4b and 4c are electrically connected, and the first solar cell string 2 and the second solar cell string 3 are connected in series. Further, by inserting the connector 6 (6a, 6b) into the first gap 8 (8a, 8b) and the connector 5 into the second gap 9, all the output terminals of the solar cell module 20 are connected and short-circuited. Is done. Moreover, when no connector is inserted, the generated power is not output from the solar cell module 20 to the outside.

  FIG. 2 is a configuration diagram showing an example of the embodiment of the solar power generation device according to the present invention.

  The manner in which the voltage is switched will be described below with reference to FIG. The solar cell module 20 is connected to an external load 19 and power storage means 17 by a power transmission cable 13, and is a positive pole of the first solar cell string of the output terminal block 4 in the junction box 12 of the solar cell module 20. The positive side is connected to the output terminal block 4a, and the negative side is connected to the output terminal block 4d that is the negative pole of the second solar cell string. By doing so, for example, assuming that the rated output voltage of each solar cell string is 12V and the rated output current is 2A, if the load 19 is an electric motor that is a DC load with a rated input voltage of 12V, By connecting the output terminal blocks 4a-4b and the output terminal blocks 4c-4d by the child 6 (6a, 6b), the solar cell module 20 having an output voltage of 12V and an output current of 4A is obtained. On the other hand, if the load 19 is a 24V electric motor, the output terminal block 4b-4c is connected by the connector 5 to form a solar cell module 20 with an output voltage of 24V and an output current of 2A. Can easily handle the rated voltage.

  Next, when the connectors 5 and 6 (6a and 6b) are inserted between all output terminal blocks (between 4a and 4b, between 4b and 4c, between 4c and 4d), the output of the solar cell module 20 is short-circuited. Thus, it becomes possible to perform the dielectric strength test of the solar cell module 20 by simplifying the work man-hours of connecting the jumper wires to the output terminal block and making all the terminals have the same potential as in the prior art.

  FIG. 5 is a wiring diagram illustrating the wiring state of the photovoltaic power generation apparatus according to the present invention.

  When a plurality of solar cell modules are connected as shown in FIG. 5, any of the solar cells can be detected even if an abnormality is detected by examining the dielectric strength of the solar voltage array (solar cell modules 20 a to 20 h) in the above-described method. It is not possible to know whether the module has a breakdown voltage failure. Conventionally, it has been necessary to remove the wiring of all the solar cell modules and perform the dielectric strength test one by one. However, according to the solar cell module of the present invention, all the solar cell modules other than performing the dielectric strength test are connected. Since the insulation withstand voltage of a specific solar cell module can be inspected only by removing the child, the number of work steps can be greatly reduced and the occurrence of wiring mistakes during rewiring hardly occurs.

  Although not particularly illustrated, there is a backflow prevention diode for preventing a backflow from the power storage means 17 such as a battery to the solar cell module even when the output of the normal solar cell module is short-circuited. Never become.

  In addition, since the generated power is not output from the solar cell module 20 until the connector is inserted, there is no need to separate the wiring when replacing the power storage means 17 or the load 19 or when performing device maintenance. Power transmission can be stopped.

  FIG. 3 is a diagram schematically illustrating an embodiment of the voltage switching structure of the solar cell module according to the present invention, where (a) is an enlarged plan view of the output terminal block, and (b) is a connector inserted therein. It is a partial cross section figure which shows a mode.

  Next, the connection structure of the output terminal block and the connector in the junction box of the solar cell module of the present invention will be described with reference to FIG. As shown in FIG. 3A, between the output terminal blocks 4 (4a to 4d) of the solar cell module 20, screw holes for inserting connectors 6 (6a, 6b) such as bolts as shown in FIG. 3B. A gap 8 (8a, 8b) is provided. By inserting (screwing) the connector 6a into the gap 8a and the connector 6b into the gap 8b, the output terminal blocks 4a and 4b and the output terminal blocks 4c and 4d are electrically connected to each other. If the rated output voltage of the battery string and the second solar cell string is 12V, the output voltage to the power transmission cable 13 that outputs generated power to the outside is 12V. Similarly, when it is desired to set the output voltage to 24V, the connector 5 is inserted into the gap 9 between the output terminal blocks 4b and 4c as shown in FIGS. 4 (a) and 4 (b).

  In addition, the power transmission cable which outputs to the outside is connected to the output terminal blocks 4a and 4d separately from the first connector 5 and the second connector 6 by screws or connectors.

  FIG. 8 is a sectional view for explaining the state of the connector and the gap in another embodiment of the solar cell module according to the present invention.

  As shown in FIG. 8, the connector 5 and the connector 6 have different screw diameters or screw pitches, the second gap 9 is the screw diameter or screw pitch of the connector 5, and the first gap 8 is a connector. The thread diameter or thread pitch of 6 is cut. It is still more preferable if the screw diameter and the screw pitch are different at the same time.

  Specifically, the screw diameter of the connector 5 and the second gap 9 is M10, and the screw diameter of the connector 6 and the first gap 8 is M6, so that the connector 5 is second as shown in FIG. Even if it is going to be inserted into the gap 8, the screw hole of the first gap 8 is smaller than the connector 5, so that the connector 6 cannot be fixed. Since it is smaller than the first gap 9, it cannot be screwed. Therefore, if such a structure is used and only the voltage setting connector is supplied to the operator, the operator will not make a mistake in setting the voltage.

  At this time, it becomes clear that the larger the difference in the outer diameter of the screw, the more the connector and the gap do not fit, but if the screw is made too large, the output terminal block 4 must be enlarged. In such a case, for example, the connector 5 is a screw having a screw pitch of US standard, and the connector 6 is a screw having a screw pitch of JIS standard, so that the screw pitch is different even if the screw diameter of the connector is approximate. You can make it impossible. Further, both the screw diameter and the screw pitch may be changed.

  By doing so, not only will the voltage setting be incorrect if the operator only passes the connector (screw) to the operator when setting the voltage, but if the voltage is changed, the change will be recovered. By checking the number of connected connectors, you can check whether you have forgotten the work, and because the screw shape of the connectors is different, you can discover work mistakes even if you make an incorrect connection and inspect the work. Can be simplified.

  FIG. 9 is a configuration diagram schematically illustrating another embodiment of the solar cell module according to the present invention.

  As shown in FIG. 9, the connection terminal blocks 4 a to 4 d are gathered and arranged in a square, a third gap 29 is provided at the center, and a connector 30 is inserted into the third gap 29 to perform voltage switching. Since the first solar cell string 2 and the second solar cell string 3 in the solar cell module 20 can be short-circuited at the same time regardless of the state of the child 5 and the connector 6, the number of work steps for performing the dielectric strength test is reduced. can do.

  Also, in this connector 30, if a dedicated screw that is different from that of the connector 5 and the connector 6 is used, there is no mistake in insertion, and if the number of screws removed after the test is confirmed, there is no forgetting to remove it. It is possible to confirm whether the wrong screw is removed or not, and the wiring inspection can be simplified.

  As described above in detail, since the voltage can be easily switched by selecting the output terminal block and the connector, for example, solar power generation in which a plurality of solar cell modules 20 (20a to 20h) as shown in FIG. 5 are connected. Even in the case of the device S, it is possible to easily cope with a change in the specification of the load 19. That is, the solar cell modules 20a to 20h in the figure are connected in parallel, and if the rated input voltage of the load 19 is, for example, a 12V pump, it is substituted when the load 19 becomes unusable due to a failure or the like. If the product has only a rated input voltage of 24V, conventionally, it has been necessary to cope with the rearrangement of the power transmission cables 13a to 13d, which are the output wiring of the solar cell module, but according to the solar cell module of the present invention, This can be dealt with only by changing the insertion position of the connector of the battery module 20 (20a to 20h), and there are no problems such as wiring rearrangement and insufficient length of the power transmission cable 13.

  Furthermore, although the number of solar cell modules in the figure is an even number, if it is an odd number, it is not possible to make 24V in series connection, so the fractional solar cell modules cannot be used for this device and the total generated power However, the solar cell module of the present invention is not limited by the number of solar cell modules because the voltage is switched by the solar cell module alone.

  In addition, in the figure, if the rated input voltage of the load 19 is a 24V pump, the solar cell module can output the conventional 24V fixed output even if an alternative pump with a rated input voltage of 12V can be prepared. If it is, it will not be possible to lower the voltage of the solar power generation device S, and emergency response will not be possible, so it will be seriously affected in areas where relief supplies such as remote villages are difficult to reach, According to the solar cell module of the invention, since it corresponds to lowering the voltage, whether or not it is possible to respond by changing the rated voltage of the load does not occur.

  6 (a) and 6 (b) are block diagrams for explaining the situation of loss due to the power transmission cable of the photovoltaic power generation apparatus according to the present invention, and FIG. 7 is a diagram showing that the photovoltaic power generation apparatus according to the present invention is placed on the roof of a house. It is a block diagram explaining the performed situation.

The use of an independent power source system using solar power generation is mainly in a place where there is no power source (such as an AC power source of a power company) in the vicinity. Therefore, it is necessary to install a solar cell module so as to obtain as much generated power as possible. However, a place where the irradiation of sunlight is good and a place where equipment such as a communication device as a load is not necessarily matched. Therefore, the power transmission cable 13 between the solar cell module 20 and the load 19 is routed from several tens of meters to about one hundred meters as shown in FIG. At this time, since the resistance component increases as the length of the power transmission cable 13 increases, measures such as reducing power transmission current per unit area and suppressing power loss are common. However, increasing the cross-sectional area means that the diameter of the power transmission cable 13 is increased, and it takes time to transport the power transmission cable due to an increase in size and weight. On the other hand, there is a maximum rating separately from the rated input voltage of the load 19, which indicates how far a voltage higher than the rated input voltage is allowed. In particular, it is known that the intensity of radio waves varies depending on the applied voltage in communication equipment and the like, and the input voltage of the communication equipment is relatively large, about 11 to 30 V. When such a load is used, the solar cell module 20 is used. The rated output voltage may be either 12V or 24V. Therefore, if the power loss caused by the length of the power transmission cable 13 from the solar cell module 20 to the load 19 is p, the power loss is p = I ² r at the 12V setting in FIG.
6 (b), the output current of the solar cell module 20 is half that when 12V is set, so p = (1/2 × I) ² · r
Thus, in the 24V setting system, the power generation loss of the solar cell module 20 is reduced to ¼ of the 12V setting. And when using a device that can only be used at 12V, if the output setting is set to 12V, a loss occurs but a device with a rated input voltage of 12V can also be used, so it can handle all of 24V and 12V, and a device of 24V Power loss of generated power can be reduced during use. Furthermore, when the load 19 is a power storage means such as a battery, the charging efficiency is improved at 24V when charging the battery, and the wiring is switched when using the 12V device, and the battery and the solar cell module are used together (charging at 12V or charging to the device). It is possible to make use of the generated power (such as continuing power supply) to the maximum and without being restricted by the rated voltage of the device.

  In addition, the power generation area on the roof can be improved by using the solar power generation device for a house. Specifically, as shown in FIG. 7, a residential solar power generation apparatus has a large number of solar cell modules mounted on the roof of a house, and the generated power is converted into AC power by a grid interconnection inverter 18, such as an electric power company. The power can be sold by flowing back into the commercial power system 10 of the solar cell, but if the roof area of the house is fully used, 20 solar cell modules A, B, and C can be placed. Assuming that the rated output voltage of one solar cell module is 12V and the output current is 2A, the output voltage of the A group and the B group is 8 series, so it becomes 96V, but there are only 4 solar cell modules in the C group. There is only 48V because there is not. For this reason, in the conventional solar cell module in which the output voltage is fixed, the group C cannot be placed and does not contribute to the photovoltaic power generation. However, according to the solar cell module of the present invention, if the output voltage setting of the group C solar cell module is 24 V, the output current is half as 1 A, but it contributes to power generation by placing it on the roof. Thus, the ratio of the power generation area to the roof area can be improved, and the power generation amount of the entire solar power generation apparatus is increased.

  In addition, although this embodiment demonstrated taking the example according to the rated voltage of common DC power supplies, such as 12V and 24V, it is not limited to this, For example, in a solar power generation device for houses, it is a voltage of 150-300V. Since the configuration is also used, a voltage suitable for it can be used, and can be applied if the voltage values of the first solar cell string and the second solar cell string are substantially the same, and within a range not departing from the gist of the present invention. It can be implemented with appropriate changes.

It is a block diagram which shows an example of embodiment of the solar cell module of this invention. It is a block diagram which shows an example of embodiment of the solar power generation device which concerns on this invention. It is a figure which illustrates typically one Example of the voltage switching structure of the solar cell module which concerns on this invention, (a) is an enlarged plan view of an output terminal block, (b) shows a mode that a connector is inserted. FIG. It is a figure which illustrates typically the other Example of the voltage switching structure of the solar cell module which concerns on this invention, (a) is a top view, (b) is a partial cross section figure. It is a wiring diagram explaining the wiring state of the solar power generation device according to the present invention. (A), (b) is a block diagram explaining the loss condition by the power transmission cable of the solar power generation device concerning this invention. It is a block diagram explaining the condition which mounted the solar power generation device concerning this invention on the roof etc. of a house. It is sectional drawing explaining the state of the connector and clearance gap in the other Example of the solar cell module which concerns on this invention. It is a block diagram which illustrates typically the other Example of the solar cell module concerning this invention. It is sectional drawing explaining the structure of a general solar cell module. It is a block diagram which shows typically one Example of the wiring connection to the conventional solar cell module. It is a block diagram which illustrates typically the structure of the conventional solar power generation device.

Explanation of symbols

1, 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h: solar cell element 2: first solar cell string 3: second solar cell string 4: output terminal blocks 5, 6, 6a, 6b, 30: Connectors 8, 8a, 8b: First gap 9: Second gap 11: Frame bodies 12, 12a, 12b: Junction boxes 13, 13a-13c: Power transmission cable 14: Light transmission substrate 15: Sealing material 16: Weather resistance Film 17: Power storage means 18: Grid interconnection inverter 19: Load 20: Solar cell modules 21, 21a, 21b: Solar cell module 22: Solar cell arrays 25, 25a to 25d: Terminal block 27: Lid 28: Fixing screw 29: Third gap 31: Solar cell panel S: Solar power generation device

Claims (5)

A plurality of solar cell string solar cell elements connected in series two arranged, a positive output terminal block hand solar cell strings to the positive side output terminal of the solar cell module, minus the other side of the solar cell string A solar cell module in which the output terminal block is a negative output terminal of the solar cell module,
In this solar cell module, the positive output terminal block of the one solar cell string, the positive output terminal block of the other solar cell string, the negative output terminal block of the one solar cell string, and the negative output terminal of the other solar cell string The base, and the negative output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string are arranged in an electrically non-conductive state so as to be close to each other,
Furthermore, by forming a screw hole so that the conductive screw-type connector can be received and electrically connected to these output terminal blocks close to each other ,
Electrically connecting the negative output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string to enable serial connection of the one solar cell string and the other solar cell string;
And,
The positive output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string are electrically connected, and the negative output terminal block of the one solar cell string and the negative output of the other solar cell string A solar cell module , wherein the one solar cell string and the other solar cell string can be connected in parallel by electrically conducting with a terminal block . A conductive screw-type connector is screwed into a screw hole for receiving a conductive screw-type connector formed on the negative output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string. The solar cell module according to claim 1, wherein the solar cell module is fitted and the two solar cell strings are connected in series. A screw hole for receiving a conductive screw-type connector formed on the positive output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string; and Conductive screw type connectors are respectively screwed into screw holes for receiving conductive connectors formed on the negative output terminal block and the negative output terminal block of the other solar cell string, and the two solar cells The solar cell module according to claim 1, wherein battery strings are connected in parallel. A screw hole for receiving a conductive screw-type connector formed on the positive output terminal block of the one solar cell string and the positive output terminal block of the other solar cell string; and A screw hole for receiving a conductive screw-type connector formed in the negative output terminal block and the negative output terminal block of the other solar cell string; and the negative output terminal block of the one solar cell string and the other A conductive screw type connector is screwed into each of the screw holes for receiving the conductive screw type connectors formed on the positive output terminal block of the solar cell string, and the two solar cell string outputs are short-circuited. The solar cell module according to claim 1 . Photovoltaic device characterized by using the solar cell module according to any one of claims 1 to 4.

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