JPWO2013105628A1 - Solar power system - Google Patents

Abstract

The solar power generation system includes a plurality of solar cell strings connected to a plurality of solar cell modules, and includes a plurality of measurement value acquisition units that acquire measurement values necessary to detect anomalies in the plurality of solar cell strings, There is a plurality of inputs, and at least one power conversion device that performs power conversion of the total power output from the plurality of solar cell strings is provided. The number of the solar cell strings corresponding to the measurement value acquired by the measurement value acquisition unit is a value obtained by dividing the number of the solar cell strings corresponding to the total power to be converted by the power converter by the input number. Is also smaller or equal.

Description

  The present invention relates to a power generation system including a power generation unit that generates electric power from renewable energy (hereinafter sometimes referred to as “renewable energy power generation system”) and a technology related thereto. One aspect of the present invention relates to a photovoltaic power generation system including a plurality of solar cell strings to which at least a plurality of solar cell modules are connected. Another aspect of the present invention relates to a technique for predicting the performance of a renewable energy power generation system.

  In recent years, with the increasing importance of protecting the global environment, expectations for renewable energy such as solar power generation have increased, and various renewable energy power generation systems have been actively introduced or planned. In particular, expectations for photovoltaic power generation are growing, and in addition to residential photovoltaic power generation systems, industrial photovoltaic power generation systems that have significantly higher output power than residential photovoltaic power generation systems are proactive. Introduced or planned.

JP 2010-114150 A JP 2011-119579 A

  In a photovoltaic power generation system, when a failure occurs in a solar cell string, it is desirable to identify the solar cell string in which the failure has occurred as soon as possible and replace or repair the failed part.

  Therefore, a solar power generation system that can detect a failure for each solar cell string has been proposed (see, for example, Patent Document 1 and Patent Document 2).

  However, in an industrial solar power generation system, since the number of solar cell strings is very large, when a failure detection unit is provided for each solar cell string, the number of failure detection units is also very large. Since the electronic components constituting the failure detection unit have a shorter lifetime than the solar cell module, it is necessary to maintain the electronic components constituting the failure detection unit in order to maintain the solar cell string in which a plurality of solar cell modules are connected. Become. Therefore, when the failure detection unit is provided, the installer of the industrial photovoltaic power generation system needs maintenance costs for the failure detection unit in addition to the installation cost of the failure detection unit. In other words, considering the cost of recovering the investment in the solar power generation system by selling the generated power of the solar power generation system to the power company, failure detection for each solar cell string in the industrial solar power generation system A configuration in which the portion is provided is not preferable.

  In general, a power generation unit that generates power from renewable energy is guaranteed a long-term power generation output. For example, in the case of a solar cell module that generates direct-current power from solar energy, a power generation output of about 10 years is guaranteed. And, in order to realize the operation of the system using the power generation unit within the warranty period of this power generation unit, repair of peripheral equipment of the power generation system such as a transformer device and a power conversion device supplied to the power system is continuously performed. There is a need to do. For example, in the case of a solar power generation system, it is necessary to continuously repair peripheral devices such as a power conversion device that converts power generated by a solar cell module. In addition, for the purpose of expanding the use of renewable energy and reducing the price, there are cases where the power purchase period is set to 10 years or more in countries where a subsidy system that defines the purchase price of renewable energy by law is enforced. In accordance with this, the generation output guarantee of the power generation unit may be required to be 10 years or more. Many peripheral devices of the power generation system have electronic components incorporated therein, and most of these electronic components are preferably repaired after 8 years.

  Although the degree of deterioration of parts is greatly influenced by the use environment, the conventional photovoltaic power generation system (see, for example, Patent Document 1 and Patent Document 2) only detects a failure, and thus obtains information on the degree of deterioration of the parts. Even if there is no problem even if it can be used for longer than the recommended replacement time for the parts, the parts are uniformly replaced at the recommended replacement time for the parts, resulting in unnecessary maintenance costs. was there.

  In view of the above situation, an object of one aspect of the present invention is to provide a solar power generation system that can quickly identify a solar cell string in which a failure has occurred while suppressing costs.

  In view of the above situation, another aspect of the present invention is a power generation capable of providing reference information when an owner of a renewable energy power generation system determines whether or not to replace a part of the renewable energy power generation system. It is an object of the present invention to provide a system performance prediction apparatus and a power generation system performance prediction method. Moreover, it aims at providing the power generation system provided with the said power generation system performance prediction apparatus.

  In order to achieve the above object, a photovoltaic power generation system according to one aspect of the present invention includes a plurality of solar cell strings to which a plurality of solar cell modules are connected, and is necessary for detecting an abnormality in the plurality of solar cell strings. A plurality of measurement value acquisition units for acquiring a measured value, the number of inputs is a plurality, and at least one power conversion device that converts the total power output from the plurality of solar cell strings, The number of the solar cell strings corresponding to the measurement values acquired by the measurement value acquisition unit is greater than the value obtained by dividing the number of the solar cell strings corresponding to the total power to be converted by the power converter by the number of inputs. Small or equal configuration. If the number of the solar cell strings corresponding to the measurement value acquired by the measurement value acquisition unit is the same value for each measurement value acquisition unit, the total number of the solar cell strings is a multiple of the number of the measurement value acquisition units. However, the total number of the solar cell strings may not be a multiple of the number of the measurement value acquisition units. The number of the solar cell strings corresponding to the measurement value acquired by the measurement value acquisition unit may be different for each measurement value acquisition unit, and is the same value in a part of the measurement value acquisition unit. Alternatively, the same value may be used in all of the measurement value acquisition units.

  According to such a configuration, the solar cell includes a measurement value acquisition unit that acquires a measurement value necessary for detecting an abnormality in a plurality of solar cell strings, compared to a case where a failure is detected for each solar cell string. It is possible to reduce the number of measurement value acquisition units that acquire measurement values necessary to detect string abnormality. Therefore, cost can be suppressed.

  Further, according to such a configuration, the number of solar cell strings corresponding to the measurement values acquired by the measurement value acquisition unit is equal to the number of solar cell strings corresponding to the total power to be converted by the power conversion device. Is smaller than or equal to the value divided by the number of inputs, so that anomalies can be detected in small units of a plurality of solar cell strings. Therefore, the solar cell string in which the failure has occurred can be identified quickly.

  Further, according to such a configuration, the number of solar cell strings corresponding to the measurement values acquired by the measurement value acquisition unit is equal to the number of solar cell strings corresponding to the total power to be converted by the power conversion device. Is less than the value divided by the number of inputs of the power conversion device, when providing a measurement value acquisition unit for acquiring a measurement value necessary for detecting an abnormality of the solar cell string for each input of the power conversion device, that is, power in the power conversion device A measurement value acquisition unit is provided for acquiring a measurement value necessary for detecting an abnormality in units of solar cell strings of a value obtained by dividing the number of solar cell strings corresponding to the total power to be converted by the number of inputs of the power conversion device. Compared to the case, an abnormality can be detected in a small unit. Therefore, the solar cell string in which the failure has occurred can be identified quickly.

  A plurality of connection boxes that collectively output power supplied from the plurality of solar cell strings; and at least one power conversion device that inputs power supplied from the plurality of connection boxes. It is desirable to provide a value acquisition unit in the power converter.

  According to such a configuration, there is no need to provide a housing for exclusive use of the measurement value acquisition unit, so that the cost can be further reduced.

  A plurality of connection boxes that collectively output power supplied from the plurality of solar cell strings; and at least one power conversion device that inputs power supplied from the plurality of connection boxes. You may make it provide a value acquisition part separately in the input side of the said power converter device.

  According to such a configuration, it is possible to aggregate the measurement value acquisition units even if they are separate bodies. Therefore, maintenance of the measurement value acquisition unit is facilitated, and costs can be suppressed.

  A plurality of junction boxes that collectively output the power supplied from the plurality of solar cell strings; and at least a current collection box that collectively outputs the power supplied from the plurality of connection boxes. It is desirable to provide one and to provide the measurement value acquisition unit in the connection box or the current collection box.

  According to such a configuration, there is no need to provide a housing for exclusive use of the measurement value acquisition unit, so that the cost can be further reduced.

  Moreover, it is desirable that the junction box and the current collection box are separate, and the measurement value acquisition unit is provided in the current collection box.

  According to such a configuration, the connection box and the current collection box are separate, and the measurement value acquisition unit can be integrated as compared with the case where the measurement value acquisition unit is provided in the connection box. Therefore, maintenance of the measurement value acquisition unit is facilitated, and costs can be suppressed.

  Moreover, it is desirable that the number of inputs of the junction box is the same as the number of the solar cell strings corresponding to the measurement value acquired by the measurement value acquisition unit.

  According to such a configuration, it is not necessary to use a branch cable for connection between the solar cell string and the connection box, so that restrictions on connection between the solar cell string and the connection box are reduced.

  An example of the measurement value acquisition unit is a current sensor.

  For example, when the maximum output is 400 kW or more, the number of solar cell strings is very large, and thus the effect of the present invention becomes remarkable.

  In addition, in a photovoltaic power generation system that requires a substation equipment that boosts the output voltage of the power converter more than 50% of the range in which the maximum total output power of the one or more power converters can be connected to the power system using the substation equipment. In the above photovoltaic power generation system, the number of solar cell strings is very large, and the amount of generated power that can be boosted by the substation equipment is increased. Therefore, the initial investment cost per system capacity (per W) is suppressed, and the present invention is achieved. The effect becomes even more pronounced.

  Further, in a photovoltaic power generation system that requires a substation equipment that boosts the output voltage of the power converter more than 90% of the range in which the maximum total output power of the one or more power converters can be connected to the power system using the substation equipment. In the above solar power generation system, since the number of solar cell strings is further increased, the initial investment cost per system capacity (per W) is suppressed, and the effect of the present invention becomes more remarkable.

  In order to achieve the above object, a power generation system performance prediction apparatus according to another aspect of the present invention obtains a performance change in a predetermined period of a power conversion unit provided in a power generation system including a power generation unit that generates power from renewable energy. A first data acquisition unit that acquires data necessary for the data conversion, a second data acquisition unit that acquires data related to a component component replacement history during the predetermined period of the power conversion unit, and the predetermined of the power conversion unit A performance prediction unit that predicts the performance of the power conversion unit after the predetermined period from the relationship between the performance change in the period and the replacement history of the component parts.

  According to such a configuration, since the prediction result of the performance prediction unit takes into account the usage record of the power converter, whether the owner of the renewable energy power generation system should replace the parts of the renewable energy power generation system. It is useful as reference information when deciding whether or not.

  Moreover, it is desirable that the performance prediction unit predicts the performance of the power conversion unit with a plurality of component replacement patterns.

  According to such a configuration, it becomes easy for the owner of the power generation system to compare and examine a plurality of component replacement patterns, and convenience for the owner of the power generation system is improved.

  Further, the data acquired by the first data acquisition unit may be data sent from the power generation system via a network.

  Further, an input unit for inputting data may be provided, and the data acquired by the second data acquisition unit may be data input by the input unit.

  In addition, in order to achieve the above object, a power generation system performance prediction method according to another aspect of the present invention includes a performance change in a predetermined period of a power conversion unit provided in a power generation system including a power generation unit that generates power from renewable energy. A first data acquisition step of acquiring data necessary for obtaining the power, a second data acquisition step of acquiring data relating to a component component replacement history in the predetermined period of the power conversion unit, and the power conversion unit A performance prediction step of predicting the performance of the power conversion unit after the predetermined period from the relationship between the performance change in the predetermined period and the replacement history of the component parts.

  In order to achieve the above object, a power generation system according to another aspect of the present invention includes a power generation unit that generates power from renewable energy, a power conversion unit that converts power generated by the power generation unit, and a power generation system. The power generation system performance prediction apparatus acquires data necessary for obtaining a power conversion unit that converts power generated by the power generation unit and the power generation unit and a performance change of the power conversion unit in a predetermined period. A first data acquisition unit; a second data acquisition unit that acquires data relating to a component component replacement history during the predetermined period of the power conversion unit; a performance change of the power conversion unit during the predetermined period; From the relationship with the exchange history, it is configured to include a performance prediction unit that predicts the performance of the power conversion unit after the predetermined period.

  According to the photovoltaic power generation system according to one aspect of the present invention, it is possible to quickly identify a solar cell string in which a failure has occurred while suppressing costs.

  According to another aspect of the present invention, it is possible to provide reference information when an owner of a renewable energy power generation system determines whether or not to replace a part of the renewable energy power generation system.

It is a figure which shows schematic structure of the solar energy power generation system which concerns on 1st Embodiment of this invention. It is a figure which shows schematic arrangement | positioning of the solar energy power generation system which concerns on 1st Embodiment of this invention. It is a figure which shows one structural example of a connection box. It is a figure which shows one structural example of a current collection box. It is a figure which shows the example of 1 structure of a power converter device. It is a figure which shows schematic structure of the solar energy power generation system which concerns on 2nd Embodiment of this invention. It is a figure which shows the other structural example of a connection box. It is a figure which shows the other structural example of a power converter device. It is a figure which shows schematic structure of the solar energy power generation system which concerns on 3rd Embodiment of this invention. It is a figure which shows the other structural example of a connection box. It is a figure which shows the other structural example of a power converter device. It is a figure which shows the other structural example of a connection box. It is a figure which shows the other structural example of a current collection box. It is a figure which shows the other structural example of a power converter device. It is a figure which shows an example of the data transmission path | route between a communication apparatus and an external server. It is a figure which shows one structural example of an external server. It is a figure which shows an example of the performance prediction of a power converter device. It is a figure which shows the required procedure etc. which differ according to the maximum output value of a photovoltaic power generation system. It is a figure which shows the required installation etc. which differ according to the maximum output value of a solar power generation system.

  Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment>
FIG. 1A is a diagram showing a schematic configuration of a photovoltaic power generation system according to the first embodiment of the present invention. The photovoltaic power generation system according to the first embodiment of the present invention is a 500 kW class photovoltaic power generation system, and includes 160 solar cell strings 1_ # 1 to 1_ # 160 and 20 junction boxes 2_ # 1 to 1_ # 1. 2_ # 20, four current collection boxes 3_ # 1 to 3_ # 4, two power converters 4_ # 1 to 4_ # 2, a substation facility 5, sunshine meter groups 6A and 6B, and a thermometer Groups 7A and 7B and two communication devices 8_ # 1 to 8_ # 2 are provided. In the following description, solar cell strings 1_ # 1 to 1_ # 160 may be referred to as solar cell string 1 when individual division is not necessary. Similarly, in the following description, the connection box 2, the current collection box 3, the power conversion device 4, and the communication device 8 may be referred to. Moreover, schematic arrangement | positioning of the solar energy power generation system which concerns on 1st Embodiment of this invention is as FIG. 1B.

  Each of the solar cell strings 1_ # 1 to 1_ # 160 has a configuration in which 13 polycrystalline solar cell modules M1 having a maximum output of 240 W are connected in series.

  Connection boxes 2_ # 1 to 2_ # 20 are connection boxes each having 8 inputs. The junction box 2_ # i collectively outputs the power supplied from the eight solar cell strings 1 _ # (8i-7) to 1_ # 8i (i is a natural number of 20 or less).

  One structural example of the connection box 2 is shown in FIG. In the configuration example shown in FIG. 2, the connection box 2 includes backflow prevention diodes D1 to D8 that prevent current from flowing back to the solar cell string 1 side, a lightning arrester 21 that suppresses a surge voltage during a lightning strike, and an overcurrent. A breaker 22 that opens the electric circuit when it flows is provided.

  The current collection boxes 3_ # 1 to 3_ # 4 are current collection boxes having five inputs. The current collection box 3_ # j collectively outputs the power supplied from the five connection boxes 2 _ # (5j-4) to 2_ # 5j (j is a natural number of 4 or less). In addition, the current collection box 3 detects an abnormality in input units, that is, in units of eight solar cell strings, and outputs the detection result.

  One structural example of the current collection box 3 is shown in FIG. In the configuration example shown in FIG. 3, the current collection box 3 includes current sensors S1 to S5, a lightning arrester 31 that suppresses a surge voltage during a lightning strike, a breaker 32 that opens an electric circuit when an overcurrent flows, and current sensors S1 to S5. The A / D converter 33 that converts the output signal (analog signal) into a digital signal and outputs the digital signal, and a power supply unit 34 are provided. The current sensor S1 of the current collection box 3_ # j has eight measurement values that are necessary to detect an abnormality in units of eight solar cell strings 1_ # (40j-39) to 1_ # (40j-32). The total output current values of the solar cell strings 1 _ # (40j-39) to 1 _ # (40j-32) are acquired, and the acquisition result is output. Further, the current sensor S2 of the current collection box 3_ # j is a measurement value necessary to detect an abnormality in units of eight solar cell strings 1_ # (40j-31) to 1_ # (40j-24). The total output current value of each of the solar cell strings 1 _ # (40j-31) to 1 _ # (40j-24) is acquired, and the acquisition result is output. The same applies to the current sensors S3 to S5 of the current collection box 3_ # j. The power supply unit 34 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V) that serves as a drive voltage for the current sensors S1 to S5 and the A / D converter 33. Voltage, DC24V voltage, etc.) and supply the current sensors S1 to S5 and the A / D converter 33. In addition, although A / D converter 33 and the power supply part 34 may be provided in all the current collection boxes 3, one A / D converter 33 may be shared by several current collection boxes 3, and the same A plurality of current collecting boxes 3 may share one power supply unit 34.

  Each of the power conversion devices 4_ # 1 to 4_ # 2 is a power conversion device having a maximum output of 240 kW and two inputs. The power conversion device 4_ # k converts DC power, which is the total power of the power supplied from the current collection box 3_ # (2k-1) and the power supplied from the current collection box 3_ # 2k, into AC power. Output (k is a natural number of 2 or less).

  An example of the configuration of the power conversion device 4 is shown in FIG. In the configuration example shown in FIG. 4, the power conversion device 4 includes a DC / AC inverter 41 that converts DC power received from two current collection boxes 3 into AC power, and outputs a sunshine meter group 6 </ b> A and a thermometer group. The A / D converter 42 that converts the output signal (analog signal) of 7A or the output signals (analog signals) of the sunshine meter group 6B and the thermometer group 7B into digital signals, and A / D converters 33 and 42 The relay device 43 that relays and transmits the output signal to the communication device 8 and the power supply unit 44 are provided. The power supply unit 44 converts a commercial AC voltage (for example, an AC 100 V voltage, an AC 200 V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, a DC 12 V voltage, a driving voltage for the A / D converter 42 and the relay 43). DC 24V voltage, etc.) and supplied to the A / D converter 42 and the repeater 43. The A / D converter 42, the repeater 43, and the power supply unit 44 may be provided in each of the two power converters 4, but one A / D converter 42 is provided by the two power converters 4. Similarly, two power converters 4 may share one repeater 43, or two power converters 4 may share one power supply unit 44.

  The A / D converter 42 converts the output signals (analog signals) of the sunshine meter group 6A and the thermometer group 7A or the output signals (analog signals) of the sunshine meter group 6B and the thermometer group 7B into digital signals and outputs them. The relay 43 that relays the output signals of the A / D converters 33 and 42 and transmits them to the communication device 8 and the power supply unit 44 may be provided in a junction box or a current collection box.

  The substation facility 5 is a substation facility having two inputs. The substation facility 5 boosts the total power of the AC power supplied from the power converter 4_ # 1 and the AC power supplied from the power converter 4_ # 2 to a high voltage (for example, 6600V) or a special high voltage (7000V or more). Output to a power system (not shown).

  The sunshine meter group 6A has ten sunshine meters, and each sunshine meter of the sunshine meter group 6A is assigned and installed in each of the connection boxes 2_ # 1 to 2_ # 10. The thermometer group 7A has ten thermometers, and each thermometer of the temperature group 7A is assigned and installed in each of the connection boxes 2_ # 1 to 2_ # 10.

  Similarly, the sunshine meter group 6B has ten sunshine meters, and each sunshine meter of the sunshine meter group 6B is assigned and installed in each of the connection boxes 2_ # 11 to 2_ # 20. The thermometer group 7B has ten thermometers, and one thermometer of the temperature group 7B is assigned and installed in each of the connection boxes 2_ # 11 to 2_ # 20.

  It should be noted that the arrangement of the sunshine meter groups 6A and 6B only needs to be able to measure the amount of solar radiation represented by each of the solar cell strings 1, and the number of the irradiometers is preferably at least a plurality of the sunshine meter groups 6A and 6B. At this time, if the pyranometers are installed at positions where they can be compared with each other, the appropriate calibration time of the pyranometer can be managed and maintenance can be performed with high accuracy. Moreover, depending on arrangement | positioning of the solar cell string 1, you may be comprised by one side of the sunshine meter group 6A or 6B.

  Similarly, the arrangement of the thermometer groups 7A and 7B only needs to be able to measure the representative temperature of each of the solar cell strings 1, and the number of thermometers is preferably at least a plurality of thermometer groups 7A and 7B. At this time, if the thermometers are installed at positions where they can be compared with each other, appropriate calibration timing of the thermometers can be managed and maintenance can be performed with high accuracy. Moreover, depending on arrangement | positioning of the solar cell string 1, you may be comprised by one side of the thermometer group 7A or 7B.

  Moreover, it is preferable that the thermometer group 7A or 7B measures the temperature of an arbitrary solar cell module M1, for example, a thermocouple element or the like is attached to the back surface of the solar cell module that does not prevent power generation, and the back surface temperature of the solar cell module is measured. It doesn't matter.

  The communication device 8_ # 1 transmits the digital signal transmitted from the repeater 43 of the power conversion device 4_ # 1 to an external server (not shown) via a network according to a predetermined communication protocol. Similarly, the communication device 8_ # 2 transmits the digital signal transmitted from the repeater 43 of the power conversion device 4_ # 2 to an external server (not shown) via the network according to a predetermined communication protocol. The communication device 8_ # 1 and the communication device 8_ # 2 may be integrated into a single communication device.

  The external server functions as an abnormality detection device, detects abnormalities in units of eight solar cell strings based on digital signals transmitted from the solar power generation system, and outputs detection results. In addition, you may make it provide an abnormality detection apparatus inside a photovoltaic power generation system instead of providing outside a photovoltaic power generation system.

  In a photovoltaic power generation system including the same number (160) of solar cell strings as the solar power generation system according to the first embodiment of the present invention, 160 current sensors are required to detect a current abnormality for each solar cell string. Become. On the other hand, since the photovoltaic power generation system according to the first embodiment of the present invention is configured to include 20 current sensors that acquire the total output current value of the 8 solar cell strings, the installation cost of the current sensor And maintenance costs can be greatly reduced.

  Moreover, the photovoltaic power generation of the same specification as the photovoltaic power generation system according to the first embodiment of the present invention (160 solar cell strings, 20 junction boxes, 4 current collection boxes, and 2 power converters). In the system, if it is attempted to detect a current abnormality of the solar cell string for each input of the power conversion device, four current sensors are required, but each current sensor obtains a total output current value of 40 solar cell strings. become. Therefore, when an abnormality is detected, it is necessary to investigate a maximum of 40 solar cell strings in order to identify a solar cell string in which a failure has occurred.

  On the other hand, in the photovoltaic power generation system according to the first embodiment of the present invention, each current sensor acquires the total output current value of the eight solar cell strings. When detected, a maximum of eight solar cell strings to investigate to identify the solar cell string in which the failure has occurred is sufficient. Therefore, the solar cell string in which the failure has occurred can be identified quickly.

  Further, for example, when it can be recognized that there is an abnormality when a decrease in power generation amount of 10% is recognized, in the photovoltaic power generation system according to the first embodiment of the present invention, one input unit of the current collection box In contrast to the solar power generation system according to the first embodiment of the present invention (160 solar cell strings and 20 junction boxes), it is noticed that an abnormality has occurred unless the solar cell string generates power at all. In the photovoltaic power generation system of four current collection boxes and two power conversion devices), if the sensitivity of the current sensor is the same as that of the photovoltaic power generation system according to the first embodiment of the present invention, the power conversion device Unless an abnormality occurs in which the four solar cell strings are not generating power at all in the input unit, it will not be noticed. Therefore, the solar power generation system according to the first embodiment of the present invention can quickly identify a solar cell string that has failed and no longer generates power.

  Alternatively, solar power generation having the same specifications as the solar power generation system according to the first embodiment of the present invention (160 solar cell strings and 20 connection boxes, 4 current collection boxes, and 2 power conversion devices) In the system, assuming that abnormality detection equivalent to that of the photovoltaic power generation system according to the first embodiment of the present invention is performed in units of power conversion devices, the current sensor is 1/40 of the total output current value of 40 solar cell strings. Sensitivity to recognize the decrease in the current value of the plant is required and the initial investment increases, and the daily inspection and calibration frequency of the current sensor itself, the pyranometer group, and the thermometer group increase, and the measurement for maintenance of the photovoltaic power generation system The burden of equipment maintenance management increases.

  In the photovoltaic power generation system according to the first embodiment of the present invention, five current sensors are provided in one current collection box 3 and 20 current sensors are provided on the input side of the current collection box 3. One current box may be provided in one connection box 2 and 20 current sensors may be provided on the output side of the connection box 2. However, the configuration in which 20 current sensors are provided on the input side of the current collection box 3 can collect current sensors compared to the configuration in which 20 current sensors are provided on the output side of the connection box 2, and In order to facilitate maintenance work and the like, a configuration in which 20 current sensors are provided on the input side of the current collection box 3 is desirable.

  The specification of the solar cell module or the number of each component used in the present embodiment is merely an example, and the present invention is not limited to the specification of the solar cell module or the number of each component used in the present embodiment. . As another example, 3840 thin-film solar cell modules with a maximum output of 130 W are provided, 80 solar cell strings in which thin-film solar cell modules with a maximum output of 130 W are connected in 8 series and 3 in parallel are provided, and the number of inputs is 8 20 units, four current collector boxes with five inputs, and two power converters with a maximum output of 500 kW and two inputs can be mentioned. In the case of a solar power generation system having this configuration, for example, the system can be installed on a rectangular site having a short side of about 150 m and a long side of about 200 m.

Second Embodiment
FIG. 5 is a diagram showing a schematic configuration of a photovoltaic power generation system according to the second embodiment of the present invention. In FIG. 5, parts of the same type as those in FIG.

  Unlike the photovoltaic power generation system according to the first embodiment of the present invention, the photovoltaic power generation system according to the second embodiment of the present invention has a configuration that does not include a current collection box, and includes 40 solar cell strings 11_. # 1 to 11_ # 40, two junction boxes 12_ # 1 to 12_ # 2, one power conversion device 14, a substation facility 15, a sunshine meter group 16, a thermometer group 17, and one Communication equipment 18.

  Each of the solar cell strings 11_ # 1 to 1_ # 40 has a configuration in which a plurality of solar cell modules are connected in series. Two adjacent solar cell strings are connected in parallel by a branch cable and then connected to the connection box 2.

  Connection boxes 12_ # 1 to 12_ # 2 are connection boxes each having 10 inputs. The connection box 12_ # 1 collectively outputs the power supplied from the 20 solar cell strings 11_ # 1 to 11_ # 20. Similarly, the junction box 12_ # 2 collectively outputs the power supplied from the 20 solar cell strings 11_ # 21 to 11_ # 40.

  One structural example of the connection box 12 is shown in FIG. In the configuration example shown in FIG. 6, the junction box 12 suppresses the reverse current prevention diodes D11 to D20 that prevent the current from flowing backward to the solar cell string 11 side, the current sensors S11 to S20, and the surge voltage during a lightning strike. A lightning arrester 23, a breaker 24 that opens an electric circuit when an overcurrent flows, an A / D converter 25 that converts the output signals (analog signals) of the current sensors S11 to S20 into digital signals, and a power supply unit 26. It has. The current sensor S11 of the junction box 12_ # 1 has two solar cell strings 11_ # 1 to 11_ # that are measurement values necessary to detect an abnormality in units of the two solar cell strings 11_ # 1 to 11_ # 2. The total output current value of 2 is acquired, and the acquisition result is output. Further, the current sensor S12 of the junction box 12_ # 2 has two solar cell strings 11_ # 3 which are measurement values necessary for detecting an abnormality in units of the two solar cell strings 11_ # 3 to 11_ # 4). The total output current value of ˜11_ # 4 is acquired, and the acquisition result is output. The same applies to the current sensors S13 to S20 of the connection box 12_ # 1. Further, the connection box 12_ # 2 is also the same as the connection box 12_ # 1 except that the solar cell string number corresponding to each current sensor is changed. The power supply unit 26 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V) that serves as a drive voltage for the current sensors S11 to S20 and the A / D converter 25. Voltage, DC24V voltage, etc.) and supply the current sensors S11 to S20 and the A / D converter 25. The A / D converter 25 and the power supply unit 26 may be provided in each of the two connection boxes 12, but one A / D converter 25 may be shared by the two connection boxes 12. One power supply unit 26 may be shared by two connection boxes 12.

  The power conversion device 14 is a power conversion device having two inputs. The power conversion device 14 converts DC power, which is the total power of the power supplied from the connection box 12_ # 1 and the power supplied from the connection box 12_ # 2, into AC power and outputs the AC power.

  One structural example of the power converter 14 is shown in FIG. In the configuration example shown in FIG. 7, the power conversion device 14 converts the DC power received from the two connection boxes 12 into AC power and outputs the AC power, and the sunshine meter group 16 and the thermometer group 17. An A / D converter 46 that converts the output signal (analog signal) into a digital signal and outputs it, and a relay 47 that relays the output signals of the A / D converters 25 and 46 to transmit to the communication device 18; And a power supply unit 48. The power supply unit 48 converts a commercial AC voltage (for example, an AC 100 V voltage, an AC 200 V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, a DC 12 V voltage, a driving voltage for the A / D converter 46 and the relay 47). DC 24V voltage, etc.) and supplied to the A / D converter 46 and the repeater 47.

  The substation facility 15 is a substation facility having one input. The substation facility 15 boosts the AC power supplied from the power converter 14 to a high voltage (for example, 6600 V) or a special high voltage (7000 V or more) and outputs the boosted power to a power system (not shown).

  The sunshine meter group 16 has ten sunshine meters, and each sunshine meter of the sunshine meter group 16 is assigned to one branch cable and installed. The thermometer group 17 has ten thermometers, and each thermometer of the temperature group 17 is assigned to each branch cable and installed.

  Moreover, it is preferable that the thermometer group 17 measures the temperature of arbitrary solar cell modules, for example, even if it attaches a thermocouple element etc. to the back surface of the solar cell module which does not prevent electric power generation, and measures a solar cell module back surface temperature. I do not care.

  The communication device 18 transmits the digital signal transmitted from the repeater 47 of the power conversion device 14 to an external server (not shown) via a network according to a predetermined communication protocol.

  The external server functions as an abnormality detection device, detects an abnormality in units of two solar cell strings 11 based on a digital signal transmitted from the photovoltaic power generation system, and outputs a detection result. In addition, you may make it provide an abnormality detection apparatus inside a photovoltaic power generation system instead of providing outside a photovoltaic power generation system.

  In the solar power generation system including the same number (40) of solar cell strings as the solar power generation system according to the second embodiment of the present invention, 40 current sensors are required to detect a current abnormality for each solar cell string. Become. On the other hand, since the photovoltaic power generation system according to the second embodiment of the present invention is configured to include 20 current sensors that acquire the total output current value of two solar battery strings, the installation cost of the current sensor And maintenance costs can be greatly reduced.

  Moreover, the same number (40 inputs) of solar cell strings as the solar power generation system according to the second embodiment of the present invention is provided, and the same specifications as the solar power generation system according to the second embodiment of the present invention (the number of inputs is 2) and In a photovoltaic power generation system having the same number (one) of power conversion devices, if it is attempted to detect a current abnormality in the solar cell string for each input of the power conversion device, two current sensors are required, but each current sensor has 20 The total output current value of each solar cell string is acquired. Therefore, when an abnormality is detected, it is necessary to investigate a maximum of 20 solar cell strings in order to identify a solar cell string in which a failure has occurred. On the other hand, in the photovoltaic power generation system according to the second embodiment of the present invention, each current sensor acquires the total output current value of two solar cell strings, so that when an abnormality is detected, the abnormality is detected. When detected, a maximum of two solar cell strings to investigate to identify the solar cell string in which a failure has occurred is sufficient. Therefore, the solar cell string in which the failure has occurred can be identified quickly.

<Third Embodiment>
FIG. 8 is a diagram showing a schematic configuration of a photovoltaic power generation system according to the third embodiment of the present invention. In FIG. 8, parts of the same type as those in FIG.

  Unlike the photovoltaic power generation system according to the first embodiment of the present invention, the photovoltaic power generation system according to the third embodiment of the present invention does not include a current collection box, and has 160 solar cell strings 121_. # 1 to 121_ # 160, 20 junction boxes 122_ # 1 to 122_ # 20, one power conversion device 124, substation equipment 125, sunshine meter group 126, thermometer group 127, and one unit Communication equipment 128.

  Each of the solar cell strings 121_ # 1 to 121_ # 160 has a configuration in which a plurality of solar cell modules are connected in series.

  The connection boxes 122_ # 1 to 122_ # 20 are connection boxes each having 8 inputs. The connection box 122_ # 1 collectively outputs the power supplied from the eight solar cell strings 121_ # 1 to 121_ # 8. Similarly, the junction box 122_ # 2 collectively outputs the electric power supplied from the eight solar cell strings 121_ # 9 to 121_ # 16. The same applies to the connection boxes 122_ # 3 to 122_ # 8.

  One structural example of the connection box 122 is shown in FIG. In the configuration example shown in FIG. 9, the connection box 122 includes backflow prevention diodes D21 to D28 that prevent a current from flowing back to the solar cell string 121 side, a lightning arrester 201 that suppresses a surge voltage during a lightning strike, and an overcurrent. A breaker 202 that opens the electric circuit when it flows is provided. Moreover, as shown in FIG. 9, you may equip the anode side of the backflow prevention diodes D21-D28 with the breakers (disconnector) B1-B8 for improving safety | security at the time of the maintenance of a solar cell string. .

  The power converter 124 is a power converter with 20 inputs. The power conversion device 124 converts DC power, which is total power supplied from the connection boxes 122_ # 1 to 122_ # 20, into AC power and outputs the AC power.

  One structural example of the power converter 124 is shown in FIG. In the configuration example shown in FIG. 10, the power conversion device 124 converts the DC power received from the 20 connection boxes 122 into AC power and outputs the AC power, current sensors S21 to S40, and current sensors. An A / D converter 204 that converts the output signals (analog signals) of S21 to S40 and the output signals (analog signals) of the sunshine meter group 126 and the thermometer group 127 into digital signals, and a power supply unit 205 are provided. ing.

  In addition, the current sensor S21 that measures the amount of current from the junction box 122_ # 1 has eight solar values that are measurement values necessary to detect an abnormality in units of eight solar cell strings 121_ # 1 to 121_ # 8. The total output current values of the battery strings 121_ # 1 to 121_ # 8 are acquired, and the acquisition result is output. Further, the current sensor S22 that measures the amount of current from the junction box 122_ # 2 has eight solar values that are measurement values necessary to detect an abnormality in units of eight solar cell strings 121_ # 9 to 121_ # 16. The total output current values of the battery strings 121_ # 9 to 121_ # 16 are acquired, and the acquisition results are output. The same applies to the current sensors S23 to S40 that measure the amount of current from the connection boxes 122_ # 3 to 122_ # 20. The power supply unit 205 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V) that serves as a drive voltage for the current sensors S21 to S40 and the A / D converter 204. Voltage, DC 24V voltage, etc.) and supply the current sensors S21 to S40 and the A / D converter 204.

  The current sensors S21 to S40, the A / D converter 204, and the like may be configured separately from the power converter 124.

  The substation facility 125 is a substation facility having one input. The substation facility 125 boosts the AC power supplied from the power converter 124 to a high voltage (for example, 6600 V) or a special high voltage (7000 V or more) and outputs the boosted power to a power system (not shown).

  The sunshine meter group 126 has 20 sunshine meters, and each sunshine meter of the sunshine meter group 126 is assigned and installed in each of the connection boxes 122_ # 1 to 122_ # 20. The thermometer group 127 has 20 thermometers, and one thermometer of the temperature group 127 is assigned and installed in each of the connection boxes 122_ # 1 to 122_ # 20.

  Moreover, it is preferable that the thermometer group 127 measures the temperature of an arbitrary solar cell module. For example, a thermocouple element or the like is attached to the back surface of a solar cell module that does not interfere with power generation, and the back surface temperature of the solar cell module is measured. I do not care.

  The communication device 128 transmits the digital signal transmitted from the A / D converter 204 of the power conversion device 124 to an external server (not shown) via a network according to a predetermined communication protocol.

  The external server functions as an abnormality detection device, detects an abnormality in units of eight solar cell strings 121 based on a digital signal transmitted from the photovoltaic power generation system, and outputs a detection result. In addition, you may make it provide an abnormality detection apparatus inside a photovoltaic power generation system instead of providing outside a photovoltaic power generation system.

  In a solar power generation system including the same number (160) of solar battery strings as the solar power generation system according to the third embodiment of the present invention, 160 current sensors are required to detect a current abnormality for each solar battery string. Become. On the other hand, since the photovoltaic power generation system according to the third embodiment of the present invention is configured to include 20 current sensors that acquire the total output current value of the eight solar cell strings, the installation cost of the current sensor And maintenance costs can be greatly reduced.

<Maintenance of solar power generation system>
Although the contents of the purchase system differ from country to country, for example, the interest and expectation of solar power generation system electric power companies are the stable power generation and the stability of the amount of power sold, and a proposal for a mechanism to ensure this is required.

  The solar power generation system according to the first to third embodiments of the present invention can detect an abnormality in a small unit of a plurality of solar cell strings, and thus corresponds to a solar cell string whose power generation amount is extremely reduced in a short time. It is possible to reach the location (measurement value acquisition unit), and it is possible for the photovoltaic power generation system power company to receive an accurate and quick maintenance service. Therefore, it is possible to avoid a loss of power sales revenue due to oversight of a decrease in power generation.

  In addition, when the measurement value acquisition unit measures the amount of power generation in the connection box unit, the fault location is identified and the corresponding connection box or current collection box is driven without having to measure and inspect all connection boxes or current collection boxes. This makes it possible to reduce maintenance time. In other words, it is possible to improve the power generation operation rate of the solar power generation system.

  In addition, by constantly monitoring the output characteristics of each junction box, the power path between the module and the power converter is monitored. It becomes possible to reduce. As a result, the burden of maintenance costs on the photovoltaic power system operator is reduced, and the recovery of the investment amount is accelerated.

  In addition, when the measurement value acquisition unit measures the amount of power generated in the connection box unit, repairing and repairing the corresponding part with the lowest output measurement value among the values of the mutual measurement value acquisition unit is the most effective at low cost. Large maintenance service.

  For example, in a photovoltaic power generation system in which solar cell strings composed of 13 series of 240 W modules are input to the connection box in 8 parallels and the output of the power conditioner (hereinafter referred to as power converter) is 250 kW, the output of the connection box is 3. 12 kW × 8 = 24.96 kW, 1 string output 240 W × 13 = 3.12 KW. Assuming that one string breaks down and the output is assumed to be 0 W, when the measured value is acquired in the connection box unit, it is detected as an output drop of 3.12 KW ÷ 24.96 kW = 12.5%. However, when the measured value is acquired in units of power conditioner, it is 3.12kW / 250kW = 1.25%. Taking into account factors such as fluctuations in solar radiation, it is difficult to detect a failure in which one string almost stops generating power.

  In other words, it is possible to reduce oversight of the decrease in the amount of power generation by subdividing the monitoring from the power control unit to the connection box unit. When the measured value acquisition unit measures the amount of power generated by each power converter, for example, assuming that the measurement error of the power converter is ± 5%, if the power selling price is 40 yen / kwh for a 2 MW system Even if there is a loss of about 2,300,000kwh x 40 yen / kwh x 0.05 = 4,600,000 yen per year, there is a possibility of overlooking, but when the measurement value acquisition unit measures the power generation amount of the connection box unit, the measurement error is one string The unit is 0.16% of the total system (640 strings @ 2 MW).

  A 2MW system can avoid overlooking over 2,300,000 kwh x 40 yen / kwh x 0.0016 = 147,200 yen per year.

  In addition, by sending information to the maintenance manager via the Internet connection, etc., the power generation amount measured by the measured value acquisition unit on the connection box basis, it is possible to bring the necessary parts for repairs to the site quickly. become.

  Moreover, even if the linear guarantee of the module power generation output is guaranteed, the power generation company is obliged to find a module whose output has decreased, and thus the linear guarantee of the real module power generation output may not function. On the other hand, measuring the amount of power generated for each module is not practical because it requires an initial cost for installing a measuring device composed of electronic components in units of modules and a cost for maintaining and replacing the measuring device itself. For these problems, the photovoltaic power generation system according to the embodiment of the present invention does not perform the measurement inspection of the total number of connection boxes or current collection boxes by making the measurement value acquisition unit measure the amount of power generation in the connection box unit. In both cases, the failure location of the solar cell string can be specified, so that maintenance based on the linear guarantee of the module power generation output can be handled.

<Fourth embodiment>
The schematic configuration of the photovoltaic power generation system according to the fourth embodiment of the present invention is that a communication line between the connection box and the power conversion device is provided instead of the communication line between the current collection box and the power conversion device. Is the same as the schematic configuration of the photovoltaic power generation system according to the first embodiment of the present invention shown in FIG. 1A. The schematic arrangement of the photovoltaic power generation system according to the fourth embodiment of the present invention is the same as the schematic arrangement of the photovoltaic power generation system according to the first embodiment of the present invention shown in FIG. 1B. The power conversion device 4 corresponds to a “power conversion unit” recited in the claims.

  An example of the configuration of the connection box 2 in this embodiment is shown in FIG. In the configuration example shown in FIG. 11, the junction box 2 has an A / D converter 27 that converts the output signals (analog signals) of the current sensors S101 to S108 into digital signals and outputs them in the configuration shown in FIG. A part 28 is added. The current sensor S101 of the connection box 2_ # 1 acquires the output current value of the solar cell string 1_ # 1, and outputs the acquisition result. Further, the current sensor S102 of the junction box 2_ # 1 acquires the output current value of the solar cell string 1_ # 2, and outputs the acquisition result. The same applies to the current sensors S103 to S108 of the junction box 2_ # 1. Also, the connection boxes 2_ # 2 to 2_ # 20 are basically the same as the connection box 2_ # 1 except that the numbers of the solar cell strings corresponding to the current sensors are changed. The power supply unit 28 converts a commercial AC voltage (for example, AC100V voltage, AC200V voltage, etc.) supplied from the outside into a predetermined DC voltage (for example, DC12V) that serves as a drive voltage for the current sensors S101 to S108 and the A / D converter 27. Voltage, DC 24V voltage, etc.) and supply the current sensors S101 to S108 and the A / D converter 27. In addition, the A / D converter 27 and the power supply unit 28 may be provided in each of the 20 connection boxes 2, but one A / D converter 27 may be shared by a plurality of connection boxes 2. In addition, one power supply unit 28 may be shared by a plurality of connection boxes 2.

  An example of the configuration of the current collection box 3 in this embodiment is shown in FIG. In the configuration example shown in FIG. 12, the current collection box 3 has the current sensors S1 to S5, the A / D conversion unit 33, and the power supply unit 34 removed from the configuration shown in FIG. 2.

  An example of the configuration of this embodiment of the power conversion device 4 is shown in FIG. In the configuration example illustrated in FIG. 13, the power conversion device 4 acquires the DC power value input to the power conversion device 4 and outputs the acquisition result to the configuration illustrated in FIG. 4, and the power conversion device. A power sensor S10 that acquires the AC power value output from 4 and outputs the acquisition result is added. The A / D converter 42 outputs the output signals (analog signals) of the sunshine meter group 6A and the thermometer group 7A or the output signals (analog signals) of the sunshine meter group 6B and the thermometer group 7B, and the output signal (analog signal) of the power sensor S9. Signal) and the output signal (analog signal) of the power sensor S10 are converted into digital signals and output. The repeater 43 relays the output signals of the A / D converters 23 and 42 and transmits them to the communication device 8.

  An example of a data transmission path between the communication devices 8_ # 1 and 8_ # 2 and the external server 102 functioning as a photovoltaic power generation system performance prediction apparatus according to an embodiment of the present invention is shown in FIG. An example of the configuration of the external server 102 is shown in FIG.

  In the example shown in FIG. 14, the communication devices 8 </ b> _ 1 and 8 </ b> _ 2 transmit data to the external server 102 via the mobile phone network or router 100 and the Internet 101. The communication device 8_ # 1 is detected, for example, every minute by an instantaneous current value data detected by a current sensor, an instantaneous sunshine intensity data detected by a sunshine meter, an instantaneous temperature data detected by a thermometer, and a power sensor. Average power value data is stored, and the data is transmitted to the external server 102 every hour, for example. The communication device 8_ # 2 is detected, for example, every minute by an instantaneous current value data detected by a current sensor, an instantaneous sunshine intensity data detected by a sunshine meter, an instantaneous temperature data detected by a thermometer, and a power sensor. Average power value data is stored, and the data is transmitted to the external server 102 every hour, for example. The communication device 8_ # 1 and the communication device 8_ # 2 may be integrated into a single communication device.

  In the configuration example illustrated in FIG. 15, the external server 102 includes a communication interface unit 103 that performs communication with the A / D converter in the connection box 2 and the power conversion device 4, a control unit 104, a memory 105, and an input unit. 106 and an output unit 107. The input unit 106 is configured by, for example, a keyboard and a pointing device. Examples of the output unit 107 include a monitor, a printer, and a storage medium interface that writes data to a computer-readable storage medium.

  The control unit 104 controls transmission / reception of data by the communication interface unit 103 and stores data received by the communication interface unit 81 and data related to replacement history of components of the power conversion device 4 input by the input unit 106. Remember me.

  In addition, the control unit 104 uses the data stored in the memory 105 to relate the performance change of the power conversion device 4 in a predetermined period and the replacement history of the component parts (for example, the conversion efficiency when the parts are not replaced). The performance of the power conversion device 4 after a predetermined period is predicted from the reduction rate, the conversion efficiency improvement rate when a certain part is replaced, and the output unit 107 outputs the prediction result. The predicted result output from the output unit 107 is a result of using the power conversion device 4, so the owner of the solar power generation system determines whether to replace the parts of the solar power generation system. It is useful as reference information.

  Note that the conversion efficiency of the power conversion device 4 can be obtained by the ratio between the input power of the power conversion device 4 and the output power of the power conversion device 4. Further, for example, unique identification information (for example, an ID number) is assigned to each power conversion device 4 so that the control unit 104 can individually identify the plurality of power conversion devices 4, and data storage by the memory 105, the control unit 104. The identification information may be associated with the prediction result output by the performance prediction / output unit 107.

  Here, an example of the performance prediction of the power converter 4 is shown in FIG. In the example shown in FIG. 16, a predetermined period is set immediately before the operation year 12 years. By accumulating and analyzing the power generation data before and after the regular maintenance in the first half, it is possible to propose and implement the optimum maintenance period in the second half.

  Among the replaceable parts provided in the power conversion device 4, for example, filter replacement is to replace a filter for preventing dust and the like from entering the power conversion device 4 by an air cooling fan provided in the power conversion device 4. This means that the optimum replacement cycle varies depending on the installation environment, but replacement is recommended in 2 to 3 years.

  For example, it is recommended that the ventilation fan of the power converter be replaced every 6 to 10 years.

  In addition, for example, it is recommended that boards such as digital control boards, DC voltage detection boards, rectifier boards, DC ground fault detection boards, IGBT drive boards, fuses, gaskets, etc. be replaced every 8 to 12 years. .

  For example, it is recommended that the circuit breaker, magnetic contactor, earth leakage circuit breaker, control power supply, electrolytic capacitor, transformer, surge absorber, inverter unit, and converter unit be replaced in the 12th to 15th years.

  The board replacement illustrated in FIG. 16 means that a board on which electronic components such as a switching element, a capacitor, and an inverter control IC provided in the power conversion device 4 are mounted is replaced. Further, the example shown in FIG. 16 is a case where the substrate replacement work is put together at a constant cycle in consideration of the efficiency of maintenance work and the like, and is performed every 8 years.

  The unit replacement shown in FIG. 16 means that an inverter unit, a converter unit, an electromagnetic contactor, an earth leakage circuit breaker, and an electrolytic capacitor constituted by relatively expensive parts are replaced. In the example shown in FIG. 16, assuming that the operation period of the power generation unit of the power generation system is 25 years, each unit of the power converter is replaced in the 12th year, which is near the middle of the above period.

  In the example shown in FIG. 16, the conversion efficiency of the power conversion device 4 after 12 years of operation with two types of component replacement patterns is predicted. Since the output unit 107 outputs the performance prediction with such a plurality of component replacement patterns, it becomes easier for the owner of the photovoltaic power generation system to compare and examine the plurality of component replacement patterns. Convenience for the user is improved.

  In this embodiment, the latter half pattern after the operation year 12 years was predicted using the first half pattern of the conversion efficiency before the operation year 12 years, but using the first half pattern shortened in accordance with the cycle of the shortest replacement part, Subsequent patterns may be predicted. For example, for parts with relatively short periods such as filter replacement, the period for the next filter replacement can be proposed according to the installation environment by comparing the conversion efficiency prediction pattern after replacement with the actual conversion efficiency pattern. Convenience is improved for the owner of the solar power generation system. Further, in this embodiment, the performance change is evaluated by the conversion efficiency pattern. However, the performance change may be evaluated by the operating rate of the power converter, or the power consumption of the peripheral device for suppressing the temperature rise of the power converter. You may evaluate by change of quantity. For example, power may be evaluated by purchasing power from the power system and cooling the ambient temperature where the power converter is installed in the air conditioner.

  The external server 102 may not be installed outside the site where the solar power generation system is provided, but may be installed within the site where the solar power generation system is provided. When installing in a site where a solar power generation system is provided, the external server 102 and the communication device 8 may communicate with each other only via the LAN without going through the Internet.

  The specification of the solar cell module or the number of each component used in the present embodiment is merely an example, and the present invention is not limited to the specification of the solar cell module or the number of each component used in the present embodiment. . As another example, 3840 thin-film solar cell modules with a maximum output of 130 W are provided, 80 solar cell strings in which thin-film solar cell modules with a maximum output of 130 W are connected in 8 series and 3 in parallel are provided, and the number of inputs is 8 20 units, four current collector boxes with five inputs, and two power converters with a maximum output of 500 kW and two inputs can be mentioned. In the case of a solar power generation system having this configuration, for example, the system can be installed on a rectangular site having a short side of about 150 m and a long side of about 200 m.

<Solar power plant>
In Japan, as shown in Fig. 17, the required procedures and the purchase price of generated power differ depending on the maximum output value of the photovoltaic power generation system. The smaller the maximum output value, the more the owner of the system. There are many benefits. Therefore, specifications aiming at the upper limit of each category (maximum output value less than 500 kW and as close to 500 kW as possible, maximum output value less than 1 MW and as close as possible to 1 MW, less than 2 MW, and maximum as close as possible to 2 MW) Output value) is preferred. However, since the maximum output of a general power converter is 100 kW or 250 kW, it can be said that the specification in which the maximum output value is set to any one of 400 kW, 900 kW, and 1.9 MW is common. In particular, when the maximum output value is 2 MW or more, a special high-voltage substation facility is required. For example, in a 1.9 MW solar power generation system and a 2.1 MW solar power generation system, the 1.9 MW solar power generation system has more facilities. Investment costs can be reduced. That is, as in the first to third embodiments described above, system installation costs and maintenance costs can be significantly reduced by quickly identifying the solar cell string in which a failure has occurred.

  Therefore, in the photovoltaic power generation system according to the present invention, the maximum output value is a predetermined value within a range of 400 kW or more and less than 500 kW, a predetermined value within a range of 900 kW or more and less than 1 MW, and a predetermined value within a range of 1.9 MW or more and less than 2 MW. It is desirable to set it to one of the values.

  In Thailand, for example, as shown in FIG. 18, necessary facilities differ depending on the maximum output value of the photovoltaic power generation system, and the smaller the maximum output value, the greater the merit for the system owner. ing. In Japan, the same or similar regulations may be implemented in the future. Therefore, when the maximum output value of the photovoltaic power generation system is classified into a plurality of categories according to laws and regulations, in each category, a predetermined value that is greater than or equal to the value obtained by subtracting 100 kW from the category upper limit threshold and less than the category upper limit threshold In addition, it is desirable to set the maximum output value of the photovoltaic power generation system according to the present invention.

  In the first embodiment and the fourth embodiment described above, the junction box and the current collection box are separate bodies, but the junction box and the current collection box may have an integrated structure.

  Moreover, in each embodiment mentioned above, although the power converter device was a structure provided with a DC / AC inverter, when the photovoltaic power generation system which concerns on this invention supplies electric power to a DC power system, a power converter device is used. A DC / DC converter that converts DC power of a certain voltage value into DC power of a different voltage value may be provided, and the substation equipment may be equipment that boosts the DC voltage.

  In the fourth embodiment described above, the external server 102 acquires data related to the performance of the power conversion device via the network, but may be input by the input unit 106. In the above-described embodiment, the data related to the replacement history of the components of the power conversion device is input by the input unit 106. However, the external server 102 acquires the data related to the replacement history of the components of the power conversion device via the network. You may do it.

  In addition, the above-mentioned “power converter” may be a high-voltage substation or special high-voltage substation required for high-voltage interconnection to the power system, or a charger / discharger that temporarily charges and discharges the generated power to the storage battery. It doesn't matter.

  As an example of a solar power generation system as an example of a power generation system including a power generation unit that generates power from renewable energy, in the case of a wind power generation system, an induction generator that generates power from the rotational motion of a windmill is described above. As the power generation unit, a high-voltage substation facility or a special high-voltage substation facility necessary for high-voltage connection to the power system may be used as the power conversion unit. Alternatively, the wind turbine and the speed increaser may be used as the power generation unit, and the induction generator that generates power from the rotational motion may be used as the power conversion unit.

  Examples of renewable energy include tidal power generation, geothermal power generation, solar thermal power generation, and the like. A generator that generates electric power from the rotational motion of a turbine may be a power generation unit that generates electric power from renewable energy. Alternatively, the power generation unit that generates power from renewable energy may be used as the power conversion unit.

  Since renewable energy uses natural energy, the amount of generated power tends to be irregular every day, and information from the power generation unit that generates power from renewable energy and the performance change of the power conversion unit over a predetermined period are obtained. It becomes important.

1_ # 1 to 1_ # 160, 11_ # 1 to 11_ # 40, 121_ # 1 to 121_160 Solar cell string 2_ # 1 to 2_ # 20, 12_ # 1 to 12_ # 2, 122_ # 1 to 122_ # 20 Junction box 3_ # 1-3_ # 4 Current collection box 4_ # 1-4_ # 2, 14, 124 Power conversion device 5, 15, 125 Substation 6A, 6B, 16, 126 Sunlight group 7A, 7B, 17, 127 Thermometer group 8_ # 1-8_ # 2, 18, 128 Communication device 21, 31, 23, 201 Arrester 22, 24, 32, 202 Breaker 25, 27, 33, 42, 46, 204 A / D converter 26, 28, 34 , 44, 48, 205 Power supply unit 41, 45, 49, 203 DC / AC inverter 43, 47 Repeater 100 Router 101 Internet 102 External server 103 Communication interface 104 Control unit 105 Memory 106 Input unit 107 Output unit B1-B8 Breaker (Disconnector)
D1-D8, D11-D28 Backflow prevention diode S1-S5, S11-S40, S101-S108 Current sensor S9, S10 Power sensor

In the fourth embodiment described above, the external server 102 acquires data related to the performance of the power conversion device via the network, but may be input by the input unit 106. In the above-described embodiment, the data related to the replacement history of the components of the power conversion device is input by the input unit 106. However, the external server 102 acquires the data related to the replacement history of the components of the power conversion device via the network. You may do it.
The power generation system performance prediction apparatus according to the embodiment described above acquires data necessary for obtaining a performance change in a predetermined period of a power conversion unit provided in a power generation system including a power generation unit that generates power from renewable energy. 1 data acquisition unit, a second data acquisition unit that acquires data related to the replacement history of the component in the predetermined period of the power conversion unit, and a performance change and replacement of the component in the predetermined period of the power conversion unit It is set as the structure provided with the performance prediction part which estimates the performance of the said power conversion part after the said predetermined period from the relationship with a log | history.
According to such a configuration, since the prediction result of the performance prediction unit takes into account the usage record of the power converter, whether the owner of the renewable energy power generation system should replace the parts of the renewable energy power generation system. Reference information when deciding whether or not can be provided.
Moreover, it is desirable that the performance prediction unit predicts the performance of the power conversion unit with a plurality of component replacement patterns.
According to such a configuration, it becomes easy for the owner of the power generation system to compare and examine a plurality of component replacement patterns, and convenience for the owner of the power generation system is improved.
Further, the data acquired by the first data acquisition unit may be data sent from the power generation system via a network.
Further, an input unit for inputting data may be provided, and the data acquired by the second data acquisition unit may be data input by the input unit.
Moreover, the power generation system performance prediction method according to the above-described embodiment obtains data necessary for obtaining a performance change in a predetermined period of a power conversion unit provided in a power generation system including a power generation unit that generates power from renewable energy. A first data acquisition step, a second data acquisition step of acquiring data relating to a component replacement history in the predetermined period of the power converter, and a performance change and the component of the power converter in the predetermined period A performance prediction step of predicting the performance of the power conversion unit after the predetermined period from the relationship with the exchange history of
The power generation system according to the above-described embodiment includes a power generation unit that generates power from renewable energy, a power conversion unit that converts the power generated by the power generation unit, and a power generation system performance prediction device, and the power generation system The system performance prediction device includes a power conversion unit that converts power generated by the power generation unit and the power generation unit, and a first data acquisition unit that acquires data necessary for obtaining a performance change in a predetermined period of the power conversion unit, From the relationship between the second data acquisition unit that acquires data related to the replacement history of the component parts in the predetermined period of the power conversion unit, and the performance change of the power conversion unit in the predetermined period and the replacement history of the component parts, And a performance prediction unit that predicts the performance of the power conversion unit after the period.

Claims (15)

A plurality of solar cell strings connected with a plurality of solar cell modules,
A plurality of measurement value acquisition units for acquiring measurement values necessary for detecting an abnormality in the plurality of solar cell strings,
A plurality of inputs, comprising at least one power conversion device that converts the total power output from the plurality of solar cell strings;
The number of the solar cell strings corresponding to the measurement value acquired by the measurement value acquisition unit is a value obtained by dividing the number of the solar cell strings corresponding to the total power to be converted by the power converter by the input number. Is a small or equal solar power generation system. A plurality of junction boxes that collectively output power supplied from the plurality of solar cell strings,
Comprising at least one current collection box that collectively outputs the power supplied from the plurality of connection boxes;
The photovoltaic power generation system according to claim 1, wherein the measurement value acquisition unit is provided in the junction box or the current collection box.   The solar power generation system according to claim 2, wherein the connection box and the current collection box are separate bodies, and the measurement value acquisition unit is provided in the current collection box.   4. The photovoltaic power generation system according to claim 2, wherein the number of inputs of the connection box is the same as the number of the solar cell strings corresponding to the measurement value acquired by the measurement value acquisition unit.   The photovoltaic power generation system according to any one of claims 1 to 4, wherein the measurement value acquisition unit is a current sensor.   The solar power generation system according to any one of claims 1 to 5, wherein the maximum output is 400 kW or more. A first data acquisition unit that acquires data necessary for obtaining a performance change in a predetermined period of a power conversion unit provided in a power generation system including a power generation unit that generates power from renewable energy;
A second data acquisition unit for acquiring data relating to a component component replacement history in the predetermined period of the power conversion unit;
A power generation system comprising: a performance prediction unit that predicts performance of the power conversion unit after the predetermined period based on a relationship between a change in performance of the power conversion unit in the predetermined period and a component replacement history. Performance prediction device.   The power generation system performance prediction apparatus according to claim 7, wherein the performance prediction unit predicts the performance of the power conversion unit with a plurality of component replacement patterns.   The power generation system performance prediction apparatus according to claim 7 or 8, wherein the data acquired by the first data acquisition unit is data transmitted from the power generation system via a network. It has an input part to input data,
The power generation system performance prediction device according to any one of claims 7 to 9, wherein the data acquired by the second data acquisition unit is data input by the input unit.   The power generation system performance prediction apparatus according to claim 7, wherein the power generation system is a solar power generation system. A first data acquisition step of acquiring data necessary for obtaining a performance change in a predetermined period of a power conversion unit provided in a power generation system including a power generation unit that generates power from renewable energy;
A second data acquisition step of acquiring data relating to a component component replacement history in the predetermined period of the power conversion unit;
A power generation system comprising: a performance prediction step of predicting the performance of the power conversion unit after the predetermined period from the relationship between the performance change of the power conversion unit in the predetermined period and the replacement history of the component parts. Performance prediction method.   The power generation system performance prediction method according to claim 12, wherein the power generation system is a solar power generation system. The power generation system performance prediction device according to any one of claims 7 to 11,
A power generation unit that generates power from renewable energy;
A power converter that converts the power generated by the power generation unit;
A power generation system comprising:   The power generation system according to claim 14, wherein the power generation system is a solar power generation system.

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