JP5777580B2 - Terminal box - Google Patents

Description

  The present invention relates to a terminal box.

  In a solar power generation system, DC power from a plurality of solar cell modules laid on the roof of a house is supplied to each electrical appliance via an inverter or the like. The plurality of solar cell modules are connected in series with a module connection cable via a terminal box disposed on the back side of each solar cell module.

  In a solar cell module, a plurality of solar cells connected in series are generally sealed and produced, and output lead wires from the solar cells are drawn into a terminal box. The terminal box includes a plurality of terminal plates to which output lead wires drawn out from solar cells are connected to one end and a module connecting cable is connected to the other end, and bypass diodes bridged between the terminal plates. I have.

  A bypass diode is for bypassing and protecting the photovoltaic cell which cannot generate electric power. That is, when a shadow of a tree or a building is cast on the solar cell module or a fallen leaf is placed on the solar cell module, the solar cell blocked by the sunlight cannot generate power. A solar cell that cannot generate electricity becomes a resistance, so if a current flows there, it generates heat and rises in temperature, and if left unattended, the solar cell will be destroyed (hot spot phenomenon). When there is such a solar cell that cannot generate power, the bypass diode bypasses the solar cell that cannot generate power and can pass the current generated by other normal solar cells. A temperature rise in the battery cell can be avoided.

  By the way, when there is a solar cell that cannot generate power and the bypass diode operates, a current generated by another normal solar cell (generally a large current of 5 to 10 A) flows through the bypass diode. Loss (power consumption) due to directional current x forward voltage occurs, and heat is generated accordingly. If this heat cannot be sufficiently released, the temperature may exceed the rated temperature of the bypass diode, leading to destruction.

  Patent Document 1 discloses a terminal box device in which a first terminal plate and a second terminal plate are connected by a first bypass diode, and a second terminal plate and a third terminal plate are connected by a second bypass diode. It describes that the shapes of the first to third terminal plates are formed so as to increase in the order of the third terminal plate, the first terminal plate, and the second terminal plate. Thus, according to Patent Document 1, since the temperature of the first to third terminal plates can be made substantially uniform in consideration of the heat transfer path and the heat dissipation path, the temperature of the first and second bypass diodes rises excessively. It is said that there is nothing to do.

JP 2006-269803 A

  In the terminal box described in Patent Document 1, a structure is adopted in which the area of the terminal plate is widened and the element body of the bypass diode is brought into contact with the terminal plate. Heat generated by the bypass diode is dissipated through this terminal board. In order to improve heat dissipation, it has also been proposed to provide a fin structure (wave-like heat dissipation part) on the terminal board.

  In the technique described in Patent Document 1, in order to increase the heat dissipation of the terminal board, it is necessary to increase the area of the terminal board or to provide a fin structure on the terminal board. For this reason, the amount of material used for the terminal plate is increased, the processing cost for providing the fin structure is increased, and the volume of the terminal box is increased to accommodate the terminal plate. Accordingly, there is a possibility that a large amount of potting material to be filled in the terminal box is required to insulate the charging part in the terminal box. That is, with the technique described in Patent Document 1, it is difficult to reduce the volume of the terminal box and the amount of material used is likely to increase, so it is difficult to reduce the manufacturing cost of the terminal box.

  This invention is made | formed in view of the above, Comprising: It aims at obtaining the terminal box which can reduce manufacturing cost.

In order to solve the above-described problems and achieve the object, a terminal box according to one aspect of the present invention is a terminal box that constitutes an output unit of a solar cell module, and is connected to a first output terminal. A plurality of terminal plates including a first terminal plate and a second terminal plate connected to the second output terminal; and a bypass diode connecting two of the plurality of terminal plates. The bypass diode is characterized in that a plurality of diodes formed of a material mainly composed of SiC , which is a wide band gap semiconductor having a positive temperature coefficient of ON voltage, are connected in parallel.

  According to the present invention, since the bypass diode is made of a material mainly composed of a wide band gap semiconductor, the heat generation of the bypass diode itself can be reduced and the heat-resistant temperature can be increased, so that the heat dissipation of the terminal board is improved. The need can be reduced. As a result, the area of the terminal plate can be reduced, and it is not necessary to provide a fin structure on the terminal plate. Since the area of the terminal board can be reduced, the amount of material used for the terminal board can be reduced. Moreover, since the area of a terminal board can be made small, the volume of the housing | casing for accommodating a terminal board can be reduced, and the usage-amount of the potting material with which it fills in a housing | casing can be reduced. Furthermore, since it is not necessary to provide a fin structure on the terminal board, the processing cost of the terminal board can be reduced. That is, since the volume of the terminal box can be reduced and the amount of material used can be reduced, the processing cost of the material can be reduced, so that the manufacturing cost of the terminal box can be reduced.

FIG. 1 is a diagram illustrating a configuration of a solar cell module to which the terminal box according to the first embodiment is applied. FIG. 2 is a diagram illustrating a configuration of the terminal box according to the first embodiment. FIG. 3 is a diagram illustrating a state before the potting material is filled in the terminal box according to the first embodiment. FIG. 4 is a diagram illustrating a state after the potting material is filled in the terminal box according to the first embodiment. FIG. 5 is a diagram illustrating a configuration of a terminal box according to the second embodiment. FIG. 6 is a diagram illustrating a configuration of a terminal box according to the third embodiment. FIG. 7 is a diagram illustrating a state of the terminal box according to the third embodiment before filling the potting material.

  Embodiments of a terminal box according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
First, the terminal box 100 according to the first embodiment will be described with reference to FIGS. FIG. 1 is a diagram illustrating a configuration of a solar cell module 1 to which a terminal box 100 is applied. FIG. 2 is a diagram illustrating an arrangement relationship of each component in the terminal box 100. FIG. 3 is a diagram showing a mounting configuration of the terminal box 100 before filling the potting material. FIG. 4 is a diagram showing a mounting configuration after filling the potting material in the terminal box 100.

  In a solar power generation system (not shown), DC power from a plurality of solar cell modules 1 laid on the roof of a house is supplied to each electrical appliance via an inverter or the like. The plurality of solar cell modules 1 are connected in series by module connection cables CA1 and CA2 via a terminal box 100 disposed on the back side of each solar cell module 1.

  In the solar cell module 1, for example, as shown in FIG. 1, a plurality of solar cells SC-1 to SC-2k connected in series are sealed, and the solar cells SC-1 to SC-1. Output lead wires LL1 to LL3 from SC-2k are drawn into the terminal box 100.

  For example, a plurality of solar cells SC-1 to SC-k connected in series constitute a solar cell string SS-1, and a plurality of solar cells SC- (k + 1) to SC-2k connected in series are The solar cell string SS-2 is configured. Solar cell string SS-1 is connected in series to solar cell string SS-2 via relay lead LL4. In the solar cell string SS-1, the + side terminal is connected to the output lead wire LL1, and the − side terminal is connected to the output lead wire LL3 via the relay lead wire LL4. In the solar cell string SS-2, the + side terminal is connected to the output lead line LL3 via the relay lead line LL4, and the − side terminal is connected to the output lead line LL2.

  The terminal box 100 includes a housing 101 (see FIGS. 2 and 3), a plurality of terminal plates TP1 to TP3, bypass diodes D1 and D2, and a potting material PM (see FIG. 4).

  The housing 101 houses a plurality of terminal plates TP1 to TP3 and bypass diodes D1 and D2. The housing 101 is formed with a plurality of openings for allowing the output lead wires LL1 to LL3 and the module connection cables CA1 and CA2 to pass therethrough. The casing 101 may have an inner casing 1011 and an outer casing 1012 as shown in FIG. 3, for example. Each of the inner casing 1011 and the outer casing 1012 may be formed of, for example, an insulator (for example, insulating resin), or a conductor (for example, iron) whose surface is coated with an insulating film. (Metal).

  The terminal plate (first terminal plate) TP1 has an output lead LL1 connected to one end via an input terminal IT1, and a + side module connection cable CA1 connected to the other end via an output terminal OT1. The terminal plate TP1 has a conductive plate TP11 formed of a conductor (for example, a metal such as copper) as shown in FIG. 3, for example.

  The terminal plate (second terminal plate) TP2 has an output lead LL2 connected to one end via an input terminal IT2, and a negative-side module connection cable CA2 connected to the other end via an output terminal OT2. The terminal plate TP2 has a conductive plate TP21 formed of a conductor (for example, a metal such as copper) as shown in FIG. 3, for example.

  The terminal plate TP3 has an output lead wire LL3 connected to one end via an input terminal IT3. The terminal plate TP3 is arranged between the terminal plate TP1 and the terminal plate TP2, and the terminal plate TP1 is connected via the bypass diode D1, and the terminal plate TP2 is connected via the bypass diode D2. The terminal plate TP3 includes a conductive plate TP31 formed of, for example, a conductor (for example, a metal such as copper).

  The conductive plate TP11 has, for example, a connection portion that protrudes toward the conductive plate TP31. The conductive plate TP21 has, for example, a connection portion that protrudes toward the conductive plate TP31. The conductive plate TP31 has, for example, a first connection part protruding toward the conductive plate TP11 and a second connection part protruding toward the conductive plate TP21.

  The bypass diode D1 is bridged between the terminal plate TP1 and the terminal plate TP3. That is, the bypass diode D1 has a cathode connected to the terminal plate TP1 and an anode connected to the terminal plate TP3. The bypass diode D1 has, for example, one diode D11 as shown in FIG. 2, and is mounted in the housing 101 in a package PCK1 including the diode D11 as shown in FIG. The terminal electrode PCK1a of the package PCK1 is connected to the cathode of the diode D11 in the package PCK1, and is connected to the connection portion of the conductive plate TP11 in the mounted state. The terminal electrode PCK1b of the package PCK1 is connected to the anode of the diode D11 in the package PCK1, and is connected to the first connection portion of the conductive plate TP31 in the mounted state.

  The bypass diode D1 is in thermal contact with the terminal plate TP1. That is, the depth side surface of the package PCK1 in FIG. 3 is in contact with the conductive plate TP11, and heat generated by the diode D11 is transmitted to the conductive plate TP11 via the package PCK1. The package PCK1 is formed of, for example, an insulating resin with good thermal conductivity.

  The bypass diode D2 is bridged between the terminal plate TP3 and the terminal plate TP2. That is, the bypass diode D2 has a cathode connected to the terminal plate TP3 and an anode connected to the terminal plate TP2. For example, as shown in FIG. 2, the bypass diode D2 has one diode D12, and as shown in FIG. 3, the bypass diode D2 is mounted in the housing 101 in a package PCK2 including the diode D12. The terminal electrode PCK2a of the package PCK2 is connected to the cathode of the diode D12 in the package PCK2, and is connected to the second connection portion of the conductive plate TP31 in the mounted state. The terminal electrode PCK2b of the package PCK2 is connected to the anode of the diode D12 in the package PCK2, and is connected to the connection portion of the conductive plate TP21 in the mounted state.

  The bypass diode D2 is in thermal contact with the terminal plate TP2. That is, the depth side surface of the package PCK2 in FIG. 3 is in contact with the conductive plate TP21, and heat generated by the diode D12 is transmitted to the conductive plate TP21 via the package PCK2. The package PCK2 is made of, for example, an insulating resin with good thermal conductivity.

  As shown in FIG. 3, a terminal portion TP11a that functions as the input terminal IT1 is connected to one end side of the conductive plate TP11, and a terminal portion TP11b that functions as the output terminal OT1 is connected to the other end side. The conductive plate TP11, the terminal part TP11a, and the terminal part TP11b may be mechanically integrated members. As shown in FIG. 3, a terminal portion TP21a that functions as an input terminal IT2 is connected to one end of the conductive plate TP21, and a terminal portion TP21b that functions as an output terminal OT2 is connected to the other end. The conductive plate TP21, the terminal part TP21a, and the terminal part TP21b may be mechanically integrated members. As shown in FIG. 3, a terminal portion TP31a that functions as an input terminal IT3 is connected to one end of the conductive plate TP31. The conductive plate TP31 and the terminal portion TP31a may be mechanically integrated members.

  The potting material PM is filled in the housing 101 (inside the inner housing 1011) so as to cover the plurality of terminal plates TP1 to TP3 and the bypass diodes D1 and D2 in the mounted state shown in FIG. That is, the potting material PM is filled so as to cover at least the bypass diodes D1 and D2 and the connection portions of the terminal plates TP1 and TP2 connected to the bypass diodes D1 and D2. Thereby, the potting material PM insulates the circumference | surroundings of the charging part (a plurality of terminal boards TP1 to TP3) in the casing 101 (inside the inner casing 1011). As the potting material PM, for example, as shown in FIG. 4, a transparent insulating resin is used.

  In such a terminal box 100, the bypass diodes D1 and D2 operate so as to bypass and protect solar cells that cannot generate power. That is, if a shadow of a tree or a building is placed on the solar cell module 1 or a fallen leaf is placed on the solar cell module 1, the solar cell blocked by the sunlight cannot generate power. A solar cell that cannot generate electricity becomes a resistance, so if a current flows there, it generates heat and rises in temperature, and if left unattended, the solar cell will be destroyed (hot spot phenomenon). When there is such a solar battery cell that cannot generate power, the bypass diode can bypass the solar battery cell that cannot generate power and flow a current generated by another normal solar battery cell.

  For example, when there is a solar battery cell that cannot generate power in the solar battery string SS-1, a bypass diode is used to bypass the current corresponding to the power generated by the solar battery string SS-2. Flow to D1. Alternatively, for example, when there is a solar battery cell that cannot generate power in the solar battery string SS-2, the current corresponding to the power generated by the solar battery string SS-1 is bypassed to the solar battery string SS-1. The current flows through the bypass diode D2. Thereby, the temperature rise in the photovoltaic cell which cannot generate electric power can be avoided.

  By the way, when there exist solar cells that cannot generate power and the bypass diodes D1 and D2 operate, the bypass diodes D1 and D2 have currents generated by other normal solar cells (generally a large current of 5 to 10A). ) Flows, a loss (power consumption) due to forward current x forward voltage occurs, and heat is generated accordingly. If this heat cannot be sufficiently released, there is a possibility that the rated temperature of the bypass diodes D1 and D2 will be exceeded, leading to destruction.

  Here, suppose that the diodes D11 and D12 are formed of a material whose main component is silicon. In this case, when a large current of 5 to 10 A flows through the diodes D11 and D12, the diodes D11 and D12 generate significant heat. Therefore, the area of the terminal plates TP1 to TP3 is increased and a fin structure is provided on the terminal plates TP1 to TP3. It is necessary to improve the heat dissipation of the terminal boards TP1 to TP3. At this time, since the areas of the terminal plates TP1 to TP3 are increased, the amount of material used for the terminal plates TP1 to TP3 tends to increase. Further, since the area of the terminal plates TP1 to TP3 is increased, the volume of the housing 101 (inner housing 1011) for housing the terminal plates TP1 to TP3 increases, and the inside of the housing 101 (inner housing 1011). There is a tendency that the amount of potting material PM used to fill the inside increases. Further, since the fin structures are provided on the terminal plates TP1 to TP3, the processing costs of the terminal plates TP1 to TP3 tend to be high. That is, it is difficult to reduce the manufacturing cost of the terminal box 100 because the volume of the terminal box 100 is difficult to reduce and the amount of material used tends to increase, and the material processing cost tends to increase.

  Therefore, in this embodiment, the diodes D11 and D12 are bypassed by using a diode formed of a material mainly composed of a wide band gap semiconductor instead of the diode formed of a material mainly composed of silicon. It aims to reduce the necessity of improving the heat dissipation of the terminal boards TP1 to TP3 by reducing the heat generation itself of the diodes D1 and D2 and increasing the heat-resistant temperature.

  Specifically, as the diodes D11 and D12 included in the bypass diodes D1 and D2, for example, diodes made of a wide band gap semiconductor such as SiC are used. Below, diode D11, D12 formed with the material which has SiC as a main component is demonstrated as SiC diode D11, D12.

  Since the SiC diodes D11 and D12 have a smaller ON resistance than the Si diode, conduction loss when the same current flows is reduced. That is, heat generation when a bypass current is passed is reduced. SiC also has a feature that it can operate at a higher temperature than Si. In other words, if the temperature can be kept below the maximum rated operating temperature of the SiC diodes D11 and D12, the heat dissipation structure for the bypass diodes (terminal plates TP1 to TP3) can be compared to the case where the Si diodes are used for the bypass diodes D1 and D2. It is also possible to reduce the heat dissipation capability.

  Therefore, if the SiC diodes D11 and D12 are used as the bypass diodes D1 and D2 of the solar cell module 1, the heat generation during the bypass operation can be reduced and the heat dissipation capability of the heat dissipation structure can be reduced. Compared with the case of using, the area of the terminal boards TP1 to TP3, which has been increased in area for heat dissipation, can be reduced. Moreover, the fin structure provided in order to raise the thermal radiation effect of terminal board TP1-TP3 becomes unnecessary. Further, since the terminal plates TP1 to TP3 are reduced and the fin structure is not required, the terminal box 100 can be reduced in volume and the amount of potting material PM used can be reduced.

  Further, by selecting the characteristics of the diode and the environment in which the solar cell module 1 is used, the bypass diodes D1 and D2 can be brought into thermal contact with the terminal plates TP1 and TP2 to dissipate heat from the terminal plates TP1 and TP2, It is also possible to use it by direct heat radiation from the bypass diodes D1 and D2 (to ensure Tj <Tjmax of the diode) (in this case, heat radiation at the terminal plates TP1 to TP3 may be unnecessary, so the terminal plate TP1 There is no need to enlarge ~ TP3).

  When it is necessary to take derating in order to extend the life of the diodes D11 and D12, the potting material PM having excellent heat conductivity is filled around the packages PCK1 and PCK2 of the diodes D11 and D12. The junction temperature of D11 and D12 can be reduced.

  If the derating is further increased to increase the reliability, the SiC diodes D11 and D12 can be brought into contact with the terminal plates TP1 to TP3 to increase the heat dissipation effect.

  As described above, in the first embodiment, the diodes D11 and D12 included in the bypass diodes D1 and D2 are formed of a material mainly composed of a wide band gap semiconductor. Thereby, since heat generation of the diodes D11 and D12 included in the bypass diodes D1 and D2 can be reduced and the heat-resistant temperature can be increased, the necessity to improve the heat dissipation of the terminal plates TP1 to TP3 can be reduced. As a result, the area of the terminal plates TP1 to TP3 can be reduced, and it is not necessary to provide a fin structure on the terminal plates TP1 to TP3. Since the area of terminal board TP1-TP3 can be made small, the usage-amount of the material of terminal board TP1-TP3 can be reduced. Further, since the areas of the terminal plates TP1 to TP3 can be reduced, the volume of the housing 101 (inner housing 1011) for housing the terminal plates TP1 to TP3 can be reduced, and the inside of the housing 101 (inside the inner housing 1011). The amount of potting material PM to be filled in can be reduced. Furthermore, since it is not necessary to provide the fin structure on the terminal plates TP1 to TP3, the processing cost of the terminal plates TP1 to TP3 can be reduced. That is, since the volume of the terminal box 100 can be reduced and the amount of material used can be reduced, and the processing cost of the material can be reduced, the manufacturing cost of the terminal box 100 can be reduced.

  In the first embodiment, the potting material PM is filled in the housing 101 so as to cover at least the bypass diodes D1 and D2 and the connection portions of the terminal plates TP1 to TP3 connected to the bypass diodes D1 and D2. . Thereby, if a material having excellent heat conductivity is used for the potting material PM, the heat of the bypass diodes D1 and D2 can be dissipated by the potting material PM, so that it becomes easy to lower the heat dissipation of the terminal plates TP1 to TP3. The areas of the plates TP1 to TP3 can be easily reduced.

  In the first embodiment, the bypass diodes D1 and D2 are in thermal contact with either of the two terminal plates to be connected. Thereby, the heat of the bypass diodes D1 and D2 can be radiated by the terminal plates TP1 and TP2 that are in thermal contact.

Embodiment 2. FIG.
Next, the terminal box 100i according to the second embodiment will be described. Below, it demonstrates focusing on a different part from Embodiment 1. FIG.

  In the first embodiment, each bypass diode includes one diode, but in the second embodiment, each bypass diode includes a plurality of diodes.

  Specifically, each of the bypass diodes D1i and D2i is configured by connecting a plurality of diodes in parallel, for example. For example, each of the bypass diodes D1i and D2i has a configuration in which two diodes connected between the terminal electrodes are connected in parallel as shown in FIG. That is, the bypass diode D1i is configured by two diodes D11 and D12 mounted on one package PCK1i, and is configured by connecting two diodes D11 and D12 in parallel between the terminal electrodes PCK1ia and PCK1ib. The bypass diode D2i is configured by two diodes D21 and D22 mounted on one package PCK2i, and is configured by connecting two diodes D21 and D22 in parallel between the terminal electrodes PCK2ia and PCK2ib.

  When diodes are connected in parallel, a large amount of current tends to flow to the side where the ON resistance, that is, the ON voltage is small, due to the difference in characteristics of the individual diodes. Naturally, the diode on the side through which a large amount of current flows increases the loss, so that heat is generated and the temperature increases.

  Here, if the diode connected in parallel is a Si diode, the ON voltage of the Si diode has a negative temperature coefficient, so that the ON voltage decreases as the temperature rises. Then, since it becomes easier to flow an electric current, in the parallel connection of Si diode, the electric current which flows will be biased. In other words, it is difficult to attempt to reduce the rated current of each diode by dividing the current in half by parallel connection unless a diode with exactly the same characteristics is used, which is impossible in practice.

  On the other hand, the ON voltage of the SiC diode has a characteristic that the temperature coefficient is positive. Even when SiC diodes are connected in parallel, since there is a difference in characteristics among the individual diodes, a large amount of current starts to flow on the side where the ON voltage is small at first. The diode on the side through which a large amount of current flows still generates heat and the temperature rises. However, since the ON voltage of the SiC diode has a positive temperature coefficient, the ON voltage increases as the temperature rises. Then, since it becomes difficult for the current to flow to the diode, the current is eventually balanced between the diodes connected in parallel. That is, if the SiC diodes D11 and D12 (or D21 and D22) are connected in parallel, the current can be shunted approximately in half, so that the rated current of each diode can be lowered. That is, a cheaper diode can be used as a bypass diode.

  When the SiC diodes are connected in parallel as a configuration of the bypass diode, using a so-called double diode in which two SiC diode chips are contained in one package, two diodes are mounted in parallel. Since only one piece is sufficient, it is effective in improving the arrangement space of the diode and the processing time (time required for mounting).

  As described above, in the second embodiment, each bypass diode D1i, D2i is configured by connecting a plurality of diodes in parallel. At this time, since each diode is made of a material mainly composed of a wide band gap semiconductor, the current can be easily balanced between the two diodes connected in parallel. As a result, the rated current of each diode can be lowered, and a diode with a small allowable current can be used, so that each bypass diode D1i, D2i can be configured at a lower cost.

  In the second embodiment, each of the bypass diodes D1i and D2i is composed of two diodes mounted in one package. Thus, when each bypass diode D1i, D2i is configured by connecting a plurality of diodes in parallel, the arrangement space of each bypass diode D1i, D2i can be reduced in a compact manner, and each bypass diode D1i, D2i can be reduced. It can be easily mounted in the housing 101 of the terminal box 100i.

Embodiment 3 FIG.
Next, the terminal box 100j according to the third embodiment will be described. Below, it demonstrates centering on a different part from Embodiment 2. FIG.

  In the second embodiment, two diodes are connected in parallel in each bypass diode, but in the third embodiment, a plurality of diodes included in the plurality of bypass diodes are bridge-connected.

  Specifically, in the terminal box 100j, as shown in FIG. 6, a plurality of diodes D11, D12, D21, and D22 included in the plurality of bypass diodes D1j and D2j are bridge-connected. For example, the plurality of diodes D11, D12, D21, and D22 are bridge-connected to form a so-called diode bridge DB.

  At this time, two diodes in the diode bridge DB are used as bypass diodes D1j and D2j having a parallel configuration. That is, the diode bridge DB of one package PCK12j can be used as two sets of bypass diodes D1j and D2j. For example, the diodes D11 and D12 can be used as the bypass diode D1j, and the diodes D21 and D22 can be used as the bypass diode D2j. The diodes D11, D12, D21, and D22 are made of SiC as in the second embodiment. With this configuration, two SiC diodes are configured in parallel in each of the bypass diodes D1j and D2j, so that the rated currents of the diodes D11, D12, D21, and D22 can be reduced as in the second embodiment. . That is, a cheaper diode can be used as the bypass diodes D1j and D2j.

  Further, for example, as shown in FIG. 7, the diode bridge DB is mounted in the housing 101 in a state of one package PCK12j containing four bridge-structured diodes (diodes D11, D12, D21, D22). The terminal electrode PCK12ja of the package PCK12j is connected to the cathodes of the diodes D11 and D12 in the package PCK12j, and is connected to the conductive plate TP11j of the terminal plate TP1j in the mounted state. The terminal electrode PCK12jb of the package PCK12j is connected to the anodes of the diodes D21 and D22 in the package PCK12j, and is connected to the conductive plate TP21j of the terminal plate TP2j in the mounted state. The terminal electrode PCK12jc of the package PCK12j is connected to the node N2 between the diode D12 and the diode D22 in the package PCK12j, and is connected to the conductive plate TP31j of the terminal plate TP3j in the mounted state. The terminal electrode PCK12jd of the package PCK12j is connected to the node N1 between the diode D11 and the diode D21 in the package PCK12j, and is connected to the conductive plate TP31j of the terminal plate TP3j in the mounted state.

  At this time, for example, as shown in FIG. 7, the terminal electrodes PCK12ja to PCK12jd can be easily electrically connected to the corresponding conductive plates TP11j to TP31j without providing connection portions protruding from the conductive plates TP11j, TP21j, and TP31j. Therefore, the shape of each conductive plate TP11j, TP21j, TP31j can be simplified, and the processing time of each conductive plate TP11j, TP21j, TP31j can be further reduced. Further, since the diode bridge DB of one package PCK12j can be used as two sets of bypass diodes D1j and D2j, it is more effective in improving the arrangement space and processing time of the bypass diodes D1j and D2j.

  As described above, in the third embodiment, each bypass diode D1j, D2j is configured by connecting a plurality of diodes in parallel. At this time, since each diode is made of a material mainly composed of a wide band gap semiconductor, the current can be easily balanced between the two diodes connected in parallel. As a result, the rated current of each diode can be lowered, and a diode with a small allowable current can be used, so that each bypass diode D1j, D2j can be configured at a lower cost.

  In the third embodiment, the bypass diode D1j is configured by two diodes D11 and D12 out of four diodes D11 to D22 mounted on one package PCK12j and bridge-connected, and the bypass diode D2j is Of the two diodes D11 to D22, the remaining two diodes D21 and D22 are used. Thereby, since the number of packages in the terminal box 100j can be reduced, workability and space saving are possible.

  As described above, the terminal box according to the present invention is useful for solar cell modules.

  1 Solar cell module, 100, 100i, 100j terminal box, 101 housing, CA1, CA2 module connection cable, D1, D2, D1i, D2i, D1j, D2j Bypass diode, IT1-IT3 input terminal, OT1, OT2 output terminal, PCK1, PCK2, PCK1i, PCK2i, PCK12j package, SC-1 to SC-2k solar cell, SS-1, SS-2 solar cell string, TP1 to TP3, TP1j to TP3j terminal board.

Claims (5)

A terminal box constituting the output part of the solar cell module,
A plurality of terminal boards including a first terminal board connected to the first output terminal and a second terminal board connected to the second output terminal;
A bypass diode connecting two terminal plates of the plurality of terminal plates;
With
The bypass diode is formed by connecting a plurality of diodes in parallel, which is formed of a material mainly composed of SiC , which is a wide band gap semiconductor having a positive temperature coefficient of ON voltage. box. The terminal box according to claim 1, further comprising a potting material filled so as to cover at least the bypass diode and a connection portion of the terminal plate connected to the bypass diode. The terminal box according to claim 2 , wherein the bypass diode is in thermal contact with one of the two terminal plates. The terminal box according to claim 3 , wherein the bypass diode includes two diodes mounted in one package. A second bypass diode that connects two terminal plates of a combination different from the two terminal plates among the plurality of terminal plates;
The bypass diode is composed of two of four diodes mounted in a package and bridge-connected,
4. The terminal box according to claim 3 , wherein the second bypass diode includes the remaining two diodes of the four diodes.

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