JP2011216811A - Solar cell abnormality diagnosis system, solar cell abnormality diagnosis apparatus and solar cell abnormality diagnosis method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar cell abnormality diagnosis system accurately diagnosing abnormality in a solar cell power generation system.SOLUTION: A solar cell abnormality diagnosis system 1 is equipped with: a solar cell power generation system 30, including a diagnostic unit 31, a power detector 22 for measuring a power generation quantity of the diagnostic unit 31, and an actinometer 33 for measuring the quantity of solar radiation; and a control unit 62, calculating a ratio of the generated power measured by the power detector 22 to theoretic power generation quantity of the diagnostic unit 31 calculated based on the quantity of solar radiation measured by the actinometer 33. The control unit 62 uses the calculated ratio to perform abnormality diagnosis of the diagnostic unit 31.

Description

  The present invention relates to a solar cell abnormality diagnosis system, a solar cell abnormality diagnosis device, and a solar cell abnormality diagnosis method, and in particular, a solar cell abnormality diagnosis system that diagnoses an abnormality of a solar cell power generation system using an amount of solar radiation measured by a solar radiation meter. The present invention relates to a solar cell abnormality diagnosis device and a solar cell abnormality diagnosis method.

  Solar cells that convert light energy into electrical energy have been attracting attention as a clean energy source with a low environmental load due to increased interest in global environmental problems.

  The solar cell power generation system converts the output of the solar cell module into AC power, and supplies power to a facility (such as a house or factory) where the solar cell power generation system is installed. Further, the solar cell power generation system supplies (sells) power to a commercial power system linked to the solar cell power generation system when the power generation amount (power generation amount) exceeds the power consumption amount of the facility. On the other hand, when the power generation amount is smaller than the power consumption amount of the facility, power is supplied to the facility from the commercial power system. For this reason, even if an abnormality occurs in the solar cell power generation system and the amount of power generation is reduced, power may be supplied from the commercial power system to the facility, and thus the solar cell power generation system may not be noticed abnormal.

  Therefore, various systems for detecting abnormalities in the solar battery power generation system have been proposed. For example, (i) a system that compares the power generation amount of another solar power generation system installed in the neighborhood, (ii) a system that compares the theoretical power generation amount predicted from past solar radiation data, and (iii) There have been proposed a system for comparing with the amount of power generation, and (iv) a system for comparing with the theoretical power generation amount expected from the actually measured solar radiation amount.

  Specifically, the system (i) compares the power generation amount of a solar cell power generation system to be subjected to abnormality diagnosis with the power generation amount of another solar cell power generation system installed in a neighboring area. In the system (i), when the power generation amount of the solar cell power generation system to be subjected to abnormality diagnosis is smaller than the power generation amount of another solar cell power generation system by a predetermined value or more, the solar cell power generation system has an abnormality. Diagnose as occurring.

  In addition, the system which compares the electric power generation amount of the solar cell power generation system used as the object which performs abnormality diagnosis with the electric power generation amount of another solar cell power generation system installed in the vicinity area is disclosed by patent document 1, for example.

  The system (ii) calculates the theoretical power generation amount of the solar cell power generation system using the past solar radiation amount data accumulated by, for example, NEDO (New Energy and Industrial Technology Development Organization), and the theoretical power generation. The amount is compared with the actual amount of power generated by the solar power generation system. The system (ii) diagnoses that an abnormality has occurred in the solar cell power generation system when the actual power generation amount of the solar cell power generation system is smaller than the theoretical power generation amount by a predetermined value or more.

  The system of (iii) above compares the power generation amount of the solar cell power generation system with the past power generation amount of the solar cell power generation system, and the power generation amount of the solar cell power generation system is compared with the past power generation amount of the solar cell power generation system. If it is smaller than a predetermined value, it is diagnosed that an abnormality has occurred in the solar cell power generation system.

  The system of (iv) above calculates the theoretical power generation amount of the solar cell power generation system using the amount of solar radiation measured by the solarimeter installed in each region, and also calculates the theoretical power generation amount and the actual power generation of the solar cell power generation system. Compare the amount. The system (iv) diagnoses that an abnormality has occurred in the solar cell power generation system when the power generation amount of the solar cell power generation system is smaller than the theoretical power generation amount by a predetermined value or more.

  A system that compares the theoretical power generation amount calculated from the actually measured solar radiation amount with the actual power generation amount is disclosed in, for example, Patent Document 2.

JP 2006-174609 A (paragraph 0059) JP 2000-40838 A (paragraph 0008)

  However, the installation environment is different between a solar cell power generation system to be subjected to abnormality diagnosis and another solar cell power generation system installed in a neighboring area. Specifically, the environment such as the installation orientation and installation angle of the solar cell modules constituting the solar cell power generation system and whether there is a tall building nearby are different. For this reason, the system (i) has a problem that it is difficult to accurately diagnose abnormality of the solar cell power generation system. In addition, when there is no other solar cell power generation system in the neighboring area, there is a problem that abnormality of the solar cell power generation system cannot be diagnosed.

  In addition, the amount of solar radiation is easily affected by the weather and the like, and fluctuates greatly in units of days (or units of time), and the amount of power generation also varies greatly in units of days (or units of hours). That is, there may be a case where the fluctuation of the power generation amount due to the weather is larger than the fluctuation of the power generation amount due to the abnormality. Specifically, the amount of solar radiation and the amount of power generation are often reduced to, for example, about 40% of the previous day due to the weather. For this reason, in the system of (ii) which compares the actual power generation amount with the theoretical power generation amount calculated from the past solar radiation amount data, the abnormality determination threshold needs to be 40% or less compared to the previous day, for example. As a result, the system (ii) has a problem that it is difficult to accurately diagnose abnormality of the solar cell power generation system.

  Further, the system (iii) has a problem that it is difficult to accurately diagnose abnormality of the solar cell power generation system for the same reason as the system (ii).

  In the system (iv), the installation environment of the solar cell power generation system and the pyranometer installed in each region are different. For this reason, the system (iv) has a problem that it is difficult to accurately diagnose abnormality of the solar cell power generation system, as in the system (i).

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a solar cell abnormality diagnosis system and a solar cell abnormality capable of accurately diagnosing the abnormality of the solar cell power generation system. A diagnostic device and a solar cell abnormality diagnosis method are provided.

  In order to achieve the above object, a solar cell abnormality diagnosis system according to a first aspect of the present invention measures a diagnostic unit having a solar cell module, a power generation amount measuring unit that measures the power generation amount of the diagnostic unit, and a solar radiation amount. A solar cell power generation system including a pyranometer, a power generation amount measured by the power generation amount measurement unit, and a calculation unit that calculates a ratio of the theoretical power generation amount of the diagnostic unit calculated based on the solar radiation amount measured by the solar radiation meter, And a diagnostic unit that performs an abnormality diagnosis of a diagnostic unit using the calculated ratio.

  In this specification, the “ratio” means not only a value obtained by dividing the actual power generation amount by the theoretical power generation amount, but also a value obtained by dividing these values by dividing the theoretical power generation amount by the actual power generation amount. It is a concept including a value obtained by multiplying (or subtracting) various coefficients.

  In the solar cell abnormality diagnosis system according to the first aspect, as described above, the power generation amount measurement unit that measures the power generation amount of the diagnostic unit, the solarimeter that measures the solar radiation amount, and the power generation amount measured by the power generation amount measurement unit And a calculation unit for calculating a ratio of the theoretical power generation amount of the diagnostic unit calculated based on the solar radiation amount measured by the pyranometer. When the power generation amount increases or decreases due to the increase or decrease of the solar radiation amount, the theoretical power generation amount also increases or decreases, so that the increase or decrease of the ratio of the actual power generation amount to the theoretical power generation amount can be suppressed. That is, the variation in the ratio of the actual power generation amount to the theoretical power generation amount can be reduced compared to the fluctuation in the power generation amount due to the weather. Thus, as described above, the diagnosis unit performs an abnormality diagnosis of the diagnostic unit using the above ratio, and thus the abnormality of the diagnostic unit (solar cell power generation system) is measured using only the power generation amount without measuring the amount of solar radiation. As compared with the case of diagnosing, the abnormality of the diagnostic unit (solar cell power generation system) can be diagnosed with high accuracy.

  Further, in the solar cell abnormality diagnosis system according to the first aspect, as described above, by providing the solar cell power generation system with the pyranometer, it is possible to prevent the installation environment of the diagnostic unit and the pyranometer from being different. As a result, the amount of solar radiation incident on the diagnostic unit can be easily calculated with high accuracy, so that an abnormality of the diagnostic unit (solar cell power generation system) can be easily diagnosed with high accuracy.

  Further, in the solar cell abnormality diagnosis system according to the first aspect, even if there is no other diagnostic unit other than the diagnostic unit to be subjected to the abnormality diagnosis, the calculated ratio is compared with the ratio calculated in the past. If it does, abnormality of a diagnostic unit (solar cell power generation system) can be diagnosed.

  In the solar cell abnormality diagnosis system according to the first aspect, preferably, the diagnosis unit does not diagnose that an abnormality has occurred in the diagnosis unit when the amount of solar radiation is less than a predetermined value. When the amount of solar radiation is less than a predetermined value, the ratio tends to decrease (or increase) as the amount of solar radiation decreases. For this reason, when the amount of solar radiation is less than a predetermined value, the diagnosis unit (solar cell power generation system) is more accurately detected by configuring the diagnosis unit so as not to diagnose that an abnormality has occurred in the diagnosis unit. Can be diagnosed well.

  In the solar cell abnormality diagnosis system according to the first aspect described above, preferably, the diagnosis unit compares the ratio of the first period with the ratio of the second period that is earlier than the first period, thereby determining the abnormality of the diagnostic unit. Make a diagnosis. If comprised in this way, since the ratio of the same diagnostic unit (the ratio of a 1st period and the ratio of a 2nd period) can be compared and an abnormality diagnosis can be performed, of a diagnostic unit (solar cell power generation system) Abnormalities can be diagnosed more accurately.

  In the solar cell abnormality diagnosis system in which the diagnosis unit performs an abnormality diagnosis of a diagnostic unit by comparing the ratio of the first period and the ratio of the second period, the ratio indicates the power generation amount measured by the power generation amount measurement unit. It may be a value divided by the amount of power generation.

  In the solar cell abnormality diagnosis system in which the ratio is a value obtained by dividing the measured power generation amount by the theoretical power generation amount, preferably a value obtained by subtracting the ratio of the first period from the ratio of the second period, or the ratio of the second period When the value obtained by dividing the ratio by the ratio of the first period is a predetermined value or more continuously for a predetermined number of times, the diagnosis unit diagnoses that an abnormality has occurred in the diagnosis unit. If comprised in this way, when a ratio falls suddenly for some reason, it will suppress that a diagnostic part performs an incorrect diagnosis that abnormality has occurred in a diagnostic unit (solar cell power generation system). Can do. Thereby, abnormality of a diagnostic unit (solar cell power generation system) can be diagnosed more accurately.

  In this case, preferably, the second period is a period of p days or more before the first period, and the reduced value or the divided value is equal to or greater than a predetermined value for q days consecutively less than or equal to p days. The diagnosis unit diagnoses that an abnormality has occurred in the diagnosis unit. If comprised in this way, since it can be diagnosed whether abnormality has generate | occur | produced in the diagnostic unit using the ratio of the 2nd period before abnormality generate | occur | produces in a diagnostic unit, a diagnostic unit (solar cell power generation) System) abnormality can be diagnosed more accurately.

  In the solar cell abnormality diagnosis system in which the ratio is a value obtained by dividing the measured power generation amount by the theoretical power generation amount, preferably, the diagnosis unit includes n lower layer units, and the ratio of the first period is the first When the ratio is equal to or less than the value obtained by multiplying the ratio of two periods by “1-1 / n”, the diagnosis unit diagnoses that an abnormality has occurred in the diagnosis unit. If comprised in this way, it can be diagnosed easily whether abnormality has generate | occur | produced in at least 1 of the lower layer unit.

  In the solar cell abnormality diagnosis system in which the ratio is a value obtained by dividing the measured power generation amount by the theoretical power generation amount, preferably a value obtained by subtracting the ratio of the first period from the ratio of the second period, or the ratio of the second period When the value obtained by dividing the ratio by the ratio of the first period is equal to or less than a predetermined value, the diagnosis unit diagnoses that an abnormality has occurred in the pyranometer. When an abnormality occurs in the pyranometer, the theoretical power generation amount decreases, and the calculated ratio increases. Thereby, the subtracted value or the divided value becomes smaller than the case where no abnormality has occurred in the pyranometer. Therefore, as described above, by configuring the diagnostic unit to diagnose that an abnormality has occurred in the pyranometer when the subtracted value or the divided value is less than or equal to the predetermined value, the pyranometer Whether or not an abnormality has occurred can be easily diagnosed.

  In the solar cell abnormality diagnosis system in which the diagnosis unit compares the ratio of the first period and the ratio of the second period, preferably, the ratio of the second period is an average value of the ratios for a plurality of days. If comprised in this way, since the dispersion | variation in the ratio of a 2nd period can be suppressed, abnormality of a diagnostic unit (solar cell power generation system) can be diagnosed more accurately.

  In the solar cell abnormality diagnosis system according to the first aspect, preferably, the diagnostic unit includes a first diagnostic unit and a second diagnostic unit, and the diagnostic unit includes a ratio of the first diagnostic unit and a ratio of the second diagnostic unit. Is compared, and an abnormality diagnosis of the first diagnosis unit is performed. If comprised in this way, since the diagnostic units in the substantially same installation environment can be compared, abnormality of a diagnostic unit (solar cell power generation system) can be diagnosed more accurately.

  In the solar cell abnormality diagnosis system in which the diagnostic unit includes a first diagnostic unit and a second diagnostic unit, the ratio may be a value obtained by dividing the power generation amount measured by the power generation amount measurement unit by the theoretical power generation amount.

  In the solar cell abnormality diagnosis system in which the ratio is a value obtained by dividing the measured power generation amount by the theoretical power generation amount, preferably, the first diagnosis unit is composed of n lower layer units, and the ratio of the first diagnosis unit However, when the ratio is equal to or less than the value obtained by multiplying the ratio of the second diagnosis unit by “1-1 / n”, the diagnosis unit diagnoses that an abnormality has occurred in the first diagnosis unit. If comprised in this way, it can be diagnosed easily whether abnormality has generate | occur | produced in at least one of the lower layer units of a 1st diagnostic unit.

In the solar cell abnormality diagnosis system in which the diagnosis unit does not diagnose that an abnormality has occurred in the diagnosis unit when the amount of solar radiation is less than a predetermined value, preferably, the diagnosis unit has an amount of solar radiation of 1.5 [kWh / m If it is less than ² ], the diagnosis unit is not diagnosed as having an abnormality. When the amount of solar radiation is less than 1.5 [kWh / m ² ], the ratio tends to decrease (or increase) as the amount of solar radiation decreases. For this reason, when the amount of solar radiation is less than 1.5 [kWh / m ² ], a diagnostic unit (solar cell power generation system) is configured so as not to diagnose that an abnormality has occurred in the diagnostic unit. ) Can be diagnosed with higher accuracy.

  In the solar cell abnormality diagnosis system according to the first aspect, preferably, the diagnostic unit is a solar cell module. If comprised in this way, since abnormality diagnosis can be performed for every solar cell module, compared with the case where abnormality diagnosis is performed for every solar cell string comprised by the several solar cell module, for example, Abnormalities of the battery power generation system can be diagnosed with higher accuracy.

  The solar cell abnormality diagnosis system according to the first aspect preferably further includes a storage unit that stores the calculated ratio. With this configuration, for example, when the diagnosis unit is configured to compare the ratio of the first period and the ratio of the second period that is earlier than the first period, the past ratio is calculated for each abnormality diagnosis. This is particularly effective because there is no need to redo it.

  The solar cell abnormality diagnosis device according to the second aspect of the present invention is based on the amount of power generation of a diagnostic unit having a solar cell module and the amount of solar radiation measured by a pyranometer provided in the solar cell power generation system including the diagnostic unit. An arithmetic unit that calculates a ratio of the calculated theoretical power generation amount of the diagnostic unit, and a diagnostic unit that performs an abnormality diagnosis of the diagnostic unit using the calculated ratio. If comprised in this way, the solar cell abnormality diagnostic apparatus which can diagnose the abnormality of a diagnostic unit (solar cell power generation system) with sufficient accuracy can be obtained.

  In the solar cell abnormality diagnosis device according to the second aspect, preferably, the diagnosis unit does not diagnose that an abnormality has occurred in the diagnosis unit when the amount of solar radiation is less than a predetermined value. When the amount of solar radiation is less than a predetermined value, the ratio tends to decrease (or increase) as the amount of solar radiation decreases. For this reason, when the amount of solar radiation is less than a predetermined value, the diagnosis unit (solar cell power generation system) is more accurately detected by configuring the diagnosis unit so as not to diagnose that an abnormality has occurred in the diagnosis unit. Can be diagnosed well.

  According to a third aspect of the present invention, there is provided a solar cell abnormality diagnosis method, comprising: measuring a power generation amount of a diagnostic unit having a solar cell module; and a solar radiation meter provided in a solar cell power generation system including the diagnostic unit. A step of calculating, a step of calculating a theoretical power generation amount of a diagnostic unit based on the measured amount of solar radiation, a step of calculating a ratio of the measured power generation amount and the calculated theoretical power generation amount, and And performing an abnormality diagnosis of a diagnostic unit using the ratio.

  In the solar cell abnormality diagnosis method according to the third aspect, as described above, the step of measuring the power generation amount of the diagnostic unit, the step of measuring the solar radiation amount, and the theoretical power generation of the diagnostic unit based on the measured solar radiation amount A step of calculating the amount, and a step of calculating a ratio of the measured power generation amount and the calculated theoretical power generation amount. When the power generation amount increases or decreases due to the increase or decrease of the solar radiation amount, the theoretical power generation amount also increases or decreases, so that the increase or decrease of the ratio of the actual power generation amount to the theoretical power generation amount can be suppressed. That is, the variation in the ratio of the actual power generation amount to the theoretical power generation amount can be reduced compared to the fluctuation in the power generation amount due to the weather. Thereby, as described above, by providing a step of performing an abnormality diagnosis of the diagnostic unit using the ratio, the abnormality of the diagnostic unit (solar cell power generation system) is measured using only the power generation amount without measuring the amount of solar radiation. Compared with the case of diagnosing, it is possible to diagnose the abnormality of the diagnostic unit (solar cell power generation system) with high accuracy.

  Moreover, in the solar cell abnormality diagnosis method according to the third aspect, as described above, by providing the solar cell power generation system with the solar meter, it is possible to suppress the difference in the installation environment between the diagnostic unit and the solar meter. As a result, the amount of solar radiation incident on the diagnostic unit can be easily calculated with high accuracy, so that an abnormality of the diagnostic unit (solar cell power generation system) can be easily diagnosed with high accuracy.

  Further, in the solar cell abnormality diagnosis method according to the third aspect, the calculated ratio is compared with the ratio calculated in the past even when there is no other diagnostic unit other than the diagnostic unit to be subjected to the abnormality diagnosis. If it does, abnormality of a diagnostic unit (solar cell power generation system) can be diagnosed.

  In the solar cell abnormality diagnosis method according to the third aspect, preferably, the step of performing abnormality diagnosis of the diagnostic unit is a step of not diagnosing that abnormality has occurred in the diagnostic unit when the amount of solar radiation is less than a predetermined value. including. When the amount of solar radiation is less than a predetermined value, the ratio tends to decrease (or increase) as the amount of solar radiation decreases. For this reason, when the amount of solar radiation is less than a predetermined value, the diagnosis unit (solar cell power generation system) can be diagnosed more accurately by not diagnosing that an abnormality has occurred in the diagnosis unit. it can.

  In the solar cell abnormality diagnosis method according to the third aspect, preferably, the step of performing an abnormality diagnosis of a diagnostic unit compares the ratio of the first period and the ratio of the second period that is earlier than the first period. The step of performing an abnormality diagnosis of a diagnostic unit is included. If comprised in this way, since the ratio of the same diagnostic unit (the ratio of a 1st period and the ratio of a 2nd period) can be compared and an abnormality diagnosis can be performed, of a diagnostic unit (solar cell power generation system) Abnormalities can be diagnosed more accurately.

  In the solar cell abnormality diagnosis method according to the third aspect, preferably, the diagnostic unit includes a first diagnostic unit and a second diagnostic unit, and the step of performing an abnormal diagnosis of the diagnostic unit includes: a ratio of the first diagnostic unit; A step of performing an abnormality diagnosis of the first diagnostic unit by comparing with a ratio of the second diagnostic unit is included. If comprised in this way, since the diagnostic units in the substantially same installation environment can be compared, abnormality of a diagnostic unit (solar cell power generation system) can be diagnosed more accurately.

  As described above, according to the present invention, a solar cell abnormality diagnosis system, a solar cell abnormality diagnosis device, and a solar cell abnormality diagnosis method capable of accurately diagnosing abnormality of a solar cell power generation system can be easily obtained. .

It is a block diagram for demonstrating the structure of the solar cell abnormality diagnostic system by 1st Embodiment of this invention. It is a figure for demonstrating the processing flow of the abnormality diagnosis of the solar cell abnormality diagnosis system by 1st Embodiment of this invention shown in FIG. 1, and is the figure which showed the various data stored in the memory | storage part of the management server. . It is a figure for demonstrating the processing flow of the abnormality diagnosis of the solar cell abnormality diagnostic system by 1st Embodiment of this invention shown in FIG. 1, and is the figure which showed the fluctuation | variation of system efficiency. It is a flowchart for demonstrating the processing flow of the abnormality diagnosis of the solar cell abnormality diagnosis system by 1st Embodiment of this invention shown in FIG. It is a flowchart for demonstrating the processing flow of the abnormality diagnosis of the solar cell abnormality diagnosis system by 1st Embodiment of this invention shown in FIG. It is a figure for demonstrating the processing flow of the abnormality diagnosis of the solar cell abnormality diagnosis system by 1st Embodiment of this invention shown in FIG. 1, and is the figure which showed the relationship between solar radiation amount and system efficiency. It is a flowchart for demonstrating the processing flow of the abnormality diagnosis of the solar cell abnormality diagnosis system by 1st Embodiment of this invention shown in FIG. It is a block diagram for demonstrating the structure of the solar cell abnormality diagnostic system by 2nd Embodiment of this invention. It is a figure for demonstrating the effect of the abnormality diagnosis method of the control part by the modification of this invention. It is a figure for demonstrating the effect of the abnormality diagnosis method of the control part by the modification of this invention. It is a figure for demonstrating the effect of the abnormality diagnosis method of the control part by the modification of this invention.

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

(First embodiment)
First, with reference to FIG. 1, the structure of the solar cell abnormality diagnosis system 1 by 1st Embodiment of this invention is demonstrated.

  As shown in FIG. 1, a solar cell abnormality diagnosis system 1 according to a first embodiment of the present invention includes a solar cell power generation system 30 including a plurality of solar cells 10 and a plurality of power conditioners (hereinafter referred to as power conditioners) 20. It is comprised by the data collection unit 40 which receives the data from the solar cell power generation system 30, the network 50, and the management server 60 which communicates between the solar cell power generation system 30 and the data collection unit 40 via the network 50. ing. The solar cell 10 and the power conditioner 20 constitute a diagnostic unit 31.

  The solar cell 10 has a function of converting solar energy into electric power and is configured to supply electric power to the power conditioner 20.

  Specifically, in the first embodiment, the solar cell 10 includes a plurality (for example, four) of solar cell strings 11. The solar cell string 11 includes a plurality of (for example, five) solar cell modules 12 connected in series. The solar cell module 12 includes a plurality (for example, several tens) of solar cells (not shown). The number of solar cell strings 11 included in one solar cell 10, the number of solar cell modules 12 included in one solar cell string 11, and the number of solar cells included in one solar cell module 12 are as follows: , Each can be set to any number. The solar cell string 11 is an example of the “lower layer unit” in the present invention.

  The solar cell string 11 is electrically connected to the power conditioner 20 and supplies the generated power to the power conditioner 20.

  The power conditioner 20 is electrically connected to one (or a plurality of) solar cells 10. The plurality of power conditioners 20 are electrically connected to the current collector 32. The current collector 32 is provided with a breaker 32a for each power conditioner 20 (diagnostic unit 31) that shuts off the circuit when an abnormal current flows.

  The current collector 32 is electrically connected to the commercial power system 2 and the load 3 of a facility (a factory, a house, etc.) where the solar cell power generation system 30 is installed. The solar cell power generation system 30 is configured to supply the power generated by the solar cell 10 to the load 3 and the commercial power system 2.

  Specifically, the power converter 20 of the solar cell power generation system 30 includes a booster circuit unit (not shown) that boosts the DC voltage from the solar cell 10, and an inverter circuit that converts the DC voltage into an AC voltage and outputs the AC voltage. A part (not shown) is provided.

  The solar cell power generation system 30 is configured to supply power to the load 3, and when the power generation amount (power generation power amount) exceeds the power consumption amount of the load 3, power is supplied to the commercial power system 2. It is configured to supply (sell electricity). On the other hand, when the power generation amount of the solar cell power generation system 30 is smaller than the power consumption amount of the load 3, power is supplied from the commercial power system 2 to the load 3.

  Further, the power conditioner 20 is provided with a breaker 21 for each solar cell string 11 that shuts off the circuit when an abnormal current flows. Further, the power conditioner 20 is provided with an electric energy detector 22 for measuring the power generation amount of the solar cell 10 connected to the power conditioner 20. The power amount detector 22 has a function of transmitting measured power generation amount data (power generation amount data) to the data collection unit 40. In addition, transmission / reception of data between the electric energy detector 22 and the data collection unit 40 may be performed using a wired line or a wireless line. The electric energy detector 22 is an example of the “power generation amount measuring unit” in the present invention.

  Further, at least one of the power conditioners 20 is provided with a storage unit 23 and a communication unit 24.

  The storage unit 23 includes data on the amount of solar radiation (sunlight amount data) measured by the solarimeter 33 for measuring the amount of solar radiation, and data on the air temperature (temperature data) measured by the thermometer 34 for measuring the temperature. And is configured to store. Note that data transmission / reception between the pyranometer 33 and the thermometer 34 and the power conditioner 20 may be performed using a wired line or a wireless line.

  Further, the pyranometer 33 and the thermometer 34 are arranged, for example, around the power conditioner 20. The pyranometer 33 and the thermometer 34 may be provided around the solar cell 10 or may be provided integrally with the solar cell 10. When the pyranometer 33 is provided integrally with the solar cell 10, it is possible to easily match the installation direction and the installation angle of the solar cell 10 (solar cell) with the installation direction and the installation angle of the pyranometer 33. Therefore, it is possible to easily calculate the later-described theoretical power generation amount of the solar cell 10 (diagnostic unit 31) using the solar radiation amount measured by the solar radiation meter 33.

  The communication unit 24 has a function of communicating with the management server 60 via the network 50, and is configured to transmit data stored in the storage unit 23 to the management server 60. It is possible to transmit the data stored in the storage unit 23 to the management server 60 via the data collection unit 40.

  The power conditioner 20 may be provided with a control unit (not shown) that controls the storage unit 23 and the communication unit 24.

  The data collection unit 40 is disposed, for example, in the periphery of the solar cell power generation system 30. The data collection unit 40 has a function of collecting power generation amount data from the power amount detector 22. Further, the data collection unit 40 has a function of communicating with the management server 60 via the network 50 and is configured to transmit the power generation amount data from the power amount detector 22 to the management server 60. Yes. The data collection unit 40 may be included in the solar cell power generation system 30, and may be provided in the current collector 32 or the power conditioner 20, for example. The data collection unit 40 may be provided with a storage unit (not shown) for storing the collected power generation amount data.

  The network 50 can use a CAN (Controller Area Network) method, a power line communication (PLC: Power Line Communication) method, an RS-485 method, and other various communication methods.

  The management server 60 includes a communication unit 61, a control unit 62 that is connected to the communication unit 61 and controls the management server 60 as a whole, and a storage unit 63 that is connected to the control unit 62. The control unit 62 is an example of the “calculation unit” and “diagnosis unit” of the present invention.

  The communication unit 61 has a function of communicating with the communication unit 24 of the power conditioner 20 or with the data collection unit 40 via the network 50, and transmits the received data to the control unit 62. It is configured.

  The control unit 62 uses the actual power generation data (power generation data) generated by the solar battery 10 (diagnostic unit 31) or the like to determine whether an abnormality has occurred in the solar battery power generation system 30 (diagnostic unit 31). It is configured to determine whether or not.

  The detailed operation of the control unit 62 will be described later.

  The storage unit 63 includes data (power generation amount data, solar radiation amount data, temperature data, etc.) received by the communication unit 61, system efficiency data calculated by the control unit 62, and a solar cell power generation system 30 (diagnostic unit 31). ) Stores data on the result of diagnosis as to whether or not an abnormality has occurred.

  An output unit 60a is connected to the control unit 62 (management server 60). The output unit 60a is configured to notify the administrator of the solar cell power generation system 30 of the abnormality diagnosis result of the solar cell power generation system 30 (diagnosis unit 31) performed by the control unit 62. For example, the output unit 60a may be a display device, or an alarm device that appeals to the manager's hearing or vision.

  Next, the operation (abnormality diagnosis method) of the control unit 62 will be described in detail.

  The control unit 62 diagnoses the presence / absence of an abnormality in each diagnostic unit 31 alone, and diagnoses the presence / absence of an abnormality by comparing a calculated value (system efficiency described later) with another diagnostic unit 31. Is configured to do.

  First, a method in which the control unit 62 diagnoses whether or not an abnormality has occurred in the diagnostic unit 31 alone will be described.

  The control unit 62 calculates the theoretical power generation amount of the diagnostic unit 31 using the solar radiation amount data and the temperature data received by the communication unit 61. Here, the theoretical power generation amount is calculated using the following formula (1).

Theoretical power generation amount [kWh] = System output amount [kWh] × (Insolation amount [kWh / m ² ] / Insolation amount in standard state [kWh / m ² ]) × Temperature correction coefficient Kt1 (1)

  The system output amount [kWh] is system output (also referred to as system capacity) [kW] × time [h]. The system output is calculated using the following equation (2).

  System output [kW] = output per solar cell module [kW] × number of solar cell modules × power conversion efficiency × correction coefficient Kα (2)

  The conversion efficiency of the power conditioner 20 is a value determined by the structure of the power conditioner 20, for example, a value around 0.95. Further, the correction coefficient Kα is a coefficient that takes into account, for example, the installation orientation and installation angle of the solar cell 10 (solar cell module 12) and other conditions that affect the amount of power generated by the solar cell 10.

  Moreover, the solar radiation amount of said Formula (1) is a value obtained from the solar radiation amount data which the communication part 61 received.

In addition, the amount of solar radiation in the standard state of the above formula (1) is the solar radiation intensity [kW / m ² ] × time [h] in the standard state (air mass = 1.5, solar cell temperature = 25 degrees). It is 1000 [kWh / m ² ].

  Further, the temperature correction coefficient Kt1 of the above equation (1) is calculated using the following equation (3).

  Kt1 = {100− (T + weighted temperature increase coefficient−25) × temperature correction coefficient Kt2} / 100 (3)

  Note that T is a value obtained from the temperature data received by the communication unit 61, and is, for example, an average daytime temperature measured by the thermometer 34. When calculating the theoretical power generation amount using the above formula (1), for example, the theoretical power generation amount is calculated by calculating the theoretical power generation amount every hour or minute and summing them. May be. In this case, if T is an average temperature for every hour or every minute, for example, it is possible to improve the accuracy of calculation of the theoretical power generation amount.

  The weighted temperature increase coefficient is, for example, 18.4 in the first embodiment. This weighted temperature increase coefficient is a value determined by the installation structure of the solar cell 10, for example, 18.4 for the open-back type, 21.5 for the roof-mounted type, 28.0 for the back-closed type, etc. It is possible to make such a value. The temperature correction coefficient Kt2 is a value determined by the crystal structure of the solar battery cell, for example, 0.485.

  In addition, the control unit 62 calculates the system efficiency of the diagnostic unit 31 using the power generation amount data of the diagnostic unit 31 received by the communication unit 61. Here, the system efficiency is calculated using the following equation (4). The system efficiency is an example of the “ratio” in the present invention.

  System efficiency [%] = (actual power generation amount [kWh] / theoretical power generation amount [kWh]) × 100 (4)

  The actual power generation amount is the actual power generation amount of the diagnostic unit 31 obtained from the power generation amount data received by the communication unit 61.

  Then, the control unit 62 compares the system efficiency of a certain date (date on which abnormality diagnosis is performed) d with the system efficiency calculated in the past to determine whether or not an abnormality has occurred in the diagnosis unit 31. to decide.

  Specifically, the control unit 62 calculates the system efficiency J (d) of the date d to be diagnosed for abnormality. In addition, the control unit 62 calculates an average value J (D) of the system efficiencies for q days that are p days or more before the date d on which the abnormality is diagnosed. Here, the average value J (D) of the system efficiencies for q days more than p days before the date d for which the abnormality is diagnosed is calculated using the following equation (5). Note that q is a value of p or less (p ≧ q). The system efficiency J (d) is an example of the “system efficiency for the first period” and the “system efficiency for the first diagnosis unit” in the present invention. The average value J (D) of system efficiency is an example of “system efficiency in the second period” of the present invention.

  J (D) = {J (d−p) + J (d− (p + 1)) +... + J (d− (p + q−2)) + J (d− (p + q−1))} / q. (5)

  Further, the control unit 62 determines whether or not a value L (d) obtained by subtracting the system efficiency J (d) of the date d from the average value J (D) of the past system efficiency is equal to or greater than a predetermined value. And the control part 62 diagnoses that abnormality has generate | occur | produced in the diagnostic unit 31, when value L (d) is more than predetermined value continuously generate | occur | produces more than p days.

In the first embodiment, the control unit 62 is configured not to perform abnormality diagnosis for dates with an amount of solar radiation of 1.5 [kWh / m ² ] or less. The reason for this will be described later. In addition, when calculating the average value J (D), the control unit 62 may be configured not to use the system efficiency value for dates with an amount of solar radiation of 1.5 [kWh / m ² ] or less.

  Next, a method in which the control unit 62 determines whether or not an abnormality has occurred by comparing the system efficiency with the other diagnostic units 31 will be described. Here, the diagnosis unit 31 to be subjected to the abnormality diagnosis will be described as a diagnosis unit 31a, and the other diagnosis units 31 will be described as diagnosis units 31b, 31c, and 31d.

  The control unit 62 calculates the system efficiency J (d) for all the diagnostic units 31 (31a, 31b, 31c and 31d) using the above equation (4). Further, the control unit 62 calculates the average value JA (d) of the system efficiencies of the diagnostic units 31b, 31c, and 31d other than the diagnostic unit 31a that is the target of the abnormality diagnosis. Here, the average value JA (d) of the system efficiencies of the diagnostic units 31b, 31c and 31d other than the diagnostic unit 31a is calculated using the following equation (6). The diagnostic unit 31a is an example of the “first diagnostic unit” in the present invention, and the diagnostic units 31b, 31c, and 31d are examples of the “second diagnostic unit” in the present invention. The average value JA (d) of system efficiency is an example of “system efficiency of second diagnostic unit” of the present invention.

  JA (d) = {Jb (d) + Jc (d) + Jd (d)} / m (6)

  Jb (d), Jc (d), and Jd (d) are the system efficiencies of the diagnostic units 31b, 31c, and 31d, respectively. Further, m is the number of diagnostic units 31 (31b, 31c, and 31d) other than the diagnostic unit 31a. In the first embodiment, m = 3.

  Further, the control unit 62 determines whether or not a value Ma (d) obtained by subtracting the system efficiency Ja (d) of the diagnostic unit 31a from the average system efficiency value JA (d) is equal to or greater than a predetermined value. And the control part 62 diagnoses that abnormality has generate | occur | produced in the diagnostic unit 31a, when value Ma (d) is more than predetermined value.

In the first embodiment, the control unit 62 is configured not to perform abnormality diagnosis for dates with an amount of solar radiation of 1.5 [kWh / m ² ] or less. Further, when calculating the average value JA (d) of the system efficiency, the control unit 62 is configured not to use the system efficiency value of the date with the solar radiation amount of 1.5 [kWh / m ² ] or less. Also good.

  As described above, in the first embodiment, the control unit 62 diagnoses the presence / absence of an abnormality in the diagnostic unit 31 alone using the past data, and communicates with the other diagnostic units 31 (31b, 31c, and 31d). Diagnose the occurrence of abnormality by comparing system efficiency between the two. Then, when it is diagnosed that an abnormality has occurred in the diagnostic unit 31 in any one of the diagnoses, the control unit 62 displays that fact on the output unit 60a, for example.

  Next, with reference to FIGS. 1-7, the process flow of the abnormality diagnosis of the solar cell abnormality diagnosis system 1 is demonstrated.

  Here, as shown in FIGS. 2 and 3, for example, when the solar cell power generation system 30 (see FIG. 1) starts operating on June 1, and an abnormality occurs in the diagnostic unit 31a on June 26 (A case where an abnormal current flows through any one of the solar cell strings 11 of the diagnostic unit 31a and the breaker 21 connected to the solar cell string 11 through which the abnormal current has flowed) will be described. 2 shows various data stored in the storage unit 63 of the management server 60 (data from the communication unit 24 of the power conditioner 20, data from the data collection unit 40, data calculated by the control unit 62, etc.). FIG. In FIG. 2, the amount of solar radiation and the amount of power generation are cumulative values for 24 hours, and the temperature is, for example, the average temperature during the day. Further, the average value J (D) of the past system efficiency in FIG. 2 is a value when, for example, p = 3 and q = 3 in the above equation (5).

  First, the solar cell power generation system 30 starts operation on June 1. Then, the installer who installed the solar cell power generation system 30 diagnoses whether or not the operating state of the solar cell power generation system 30 is normal in the initial stage of installation (for example, from June 1 to June 5). For the diagnosis work in the initial stage of installation, it is possible to use a method generally performed conventionally. In addition, the installer or the like confirms whether the system efficiency from June 1 to June 5 is equal to or higher than a desired value (for example, 70%). A diagnosis may be made.

  Next, the abnormality diagnosis processing flow performed by the control unit 62 of the management server 60 will be described.

  As shown in FIG. 4, the abnormality diagnosis processing flow performed by the control unit 62 of the management server 60 includes, as described above, step S1 for diagnosing whether or not an abnormality has occurred in the diagnostic unit 31 alone using past data; Step S2 for diagnosing whether or not an abnormality has occurred by comparing the system efficiency with other diagnostic units 31, and when diagnosing that an abnormality has occurred in the diagnostic unit 31, the output unit 60a notifies the fact. Is output (for example, displayed).

  Here, in steps S1 and S2, the control unit 62 does not diagnose the occurrence of abnormality in the diagnostic unit 31 by comparing the power generation amounts, but by dividing the actual power generation amount by the theoretical power generation amount. The reason for diagnosing the occurrence of abnormality in the diagnostic unit 31 using the obtained system efficiency will be described.

  As shown in FIG. 2, for example, when June 1 and June 10 are compared, the amount of power generated on June 1 of the diagnostic unit 31a (624.4 [kWh]) is June 10 The amount of power generated (138.8 [kWh]) is about 78% lower. That is, the decrease (fluctuation) in the amount of power generation is large even though no abnormality has occurred in the diagnostic unit 31a. For this reason, when abnormality diagnosis is performed by comparing the power generation amounts, the abnormality cannot be detected unless the power generation amount of the diagnostic unit 31 is close to zero.

  On the other hand, for example, the system efficiency (76.7 [%]) on June 10 is about 2% lower than the system efficiency (78.3 [%]) on June 1 of the diagnostic unit 31a. There is only. The system efficiency after June 26 of the diagnostic unit 31a (when an abnormality has occurred in the diagnostic unit 31a) is the system efficiency before June 25 (when no abnormality has occurred in the diagnostic unit 31a). On the other hand, it is about 25% lower. That is, when the abnormality is not generated in the diagnostic unit 31a, the fluctuation of the system efficiency is small, and when the abnormality is generated in the diagnostic unit 31a, the fluctuation of the system efficiency is large.

  For this reason, it is possible to improve the accuracy of abnormality diagnosis by diagnosing the occurrence of abnormality in the diagnostic unit 31 using system efficiency.

  Hereinafter, steps S1, S2 and S3 will be described in detail.

  Step S1 includes steps S11 to S17 as shown in FIG. In step S11, the control unit 62 of the management server 60 determines whether or not the number of past data is greater than or equal to a predetermined value (for example, for 5 days). When the control unit 62 determines that the past data number does not exist for five days or more (when the date on which the abnormality diagnosis is performed is from June 1 to June 5), the process proceeds to step S2. On the other hand, when the control unit 62 determines that the number of past data is greater than or equal to a predetermined value (for example, for 5 days) (when the target date for abnormality diagnosis is after June 6), the process proceeds to step S12.

In step S12, the control unit 62 determines whether or not the amount of solar radiation on the date on which abnormality diagnosis is performed is equal to or greater than a predetermined value (for example, 1.5 [kWh / m ² ]). When the control unit 62 determines that the amount of solar radiation is less than 1.5 [kWh / m ² ], the process proceeds to step S2. On the other hand, when the control unit 62 determines that the amount of solar radiation is 1.5 [kWh / m ² ] or more, the process proceeds to step S13.

Here, the reason for determining whether the amount of solar radiation is 1.5 [kWh / m ² ] or more will be described. As shown in FIG. 6, when the solar radiation amount is about 1.5 [kWh / m ² ] or more, the system efficiency calculated by the above formula (4) ranges from about 70 [%] to about 81 [%]. It remains almost constant. On the other hand, when the solar radiation amount is less than about 1.5 [kWh / m ² ], the system efficiency tends to decrease as the solar radiation amount decreases.

That is, when the amount of solar radiation is not about 1.5 [kWh / m ² ] or more (when the date on which abnormality diagnosis is performed is June 11), the system efficiency is lowered, and the solar cell power generation system 30 (diagnosis unit 31). ) Is more likely to be wrongly diagnosed. For this reason, in the solar cell abnormality diagnosis system 1, when the amount of solar radiation is less than 1.5 [kWh / m ² ] (for example, when it is extremely cloudy), abnormality diagnosis is not performed.

In addition, when the solar radiation amount is not about 1.5 [kWh / m ² ] or more, the system efficiency becomes low because the wavelength of the light measured by the solar radiation meter 33 and the wavelength of the light that the solar cell 10 converts into electric power. Are not necessarily the same, and the light that the solar cell 10 converts to electric power is considered to be easily absorbed (or reflected) by clouds or the like.

  Then, as shown in FIG. 5, in step S <b> 13, the control unit 62 uses the average value J (D) of the past system efficiency calculated by the above formula (5) for the date d of the target to be diagnosed for abnormality. It is determined whether or not a value L (d) obtained by subtracting the system efficiency J (d) is equal to or greater than a predetermined value E1 (for example, 10 [%]). It should be noted that the predetermined value E1 that is a determination threshold may be a value other than 10 [%].

  For example, in the first embodiment, the diagnostic unit 31 includes four solar cell strings 11, and therefore, when an abnormality occurs in one solar cell string 11 (when one breaker 21 is shut off), the diagnostic unit The predetermined value E1 may be set so that 31 abnormalities can be detected. That is, the predetermined value E1 is set so as to determine whether or not the system efficiency J (d) is equal to or less than a value obtained by multiplying the average value J (D) of the past system efficiency by “1-1 / n”. May be. Note that n is the number of solar cell strings 11 included in the diagnostic unit 31 to be subjected to abnormality diagnosis, and is 4 in the first embodiment.

  Specifically, since 1-1 / n = 0.75, J (D) × 0.75 ≧ J (d) and L (d) = J (D) −J (d) ≧ J (D) × 0.25. Since J (D) is about 70 [%] to about 81 [%], J (D) × 0.25 = about 17.5 [%] to about 20.3 [%]. For this reason, the predetermined value E1 that is a threshold for determination may be set to about 17.5 [%] to about 20.3 [%]. In the first embodiment, the predetermined value E1 is set to be smaller than about 17.5 [%] to about 20.3 [%], for example, 10 [%], so that one solar cell string 11 is abnormal. When this occurs, it is possible to reliably detect an abnormality in the diagnostic unit 31.

  When the control unit 62 determines in step S13 that the value L (d) is equal to or greater than a predetermined value E1 (for example, 10 [%]) (in the case of the power conditioner 20a from June 26 to 29), step S14 Proceed to Thereafter, in step S14, a counter value f indicating the number of times that the value L (d) is determined to be equal to or greater than a predetermined value E1 (for example, 10 [%]) is set to f = f + 1, and the process proceeds to step S15. In step S13, when the control unit 62 determines that the value L (d) is less than the predetermined value E1 (for example, 10 [%]), the process proceeds to step S16, and the counter value f is set to f = 0. Then, the process proceeds to step S2. In this case, when the counter value f is f ≧ 3, the counter value f need not be set to f = 0.

  In step S15, the control unit 62 determines whether the counter value f is 3 or more. When it is determined that the counter value f is not 3 or more, the process proceeds to step S2. On the other hand, when it is determined that the counter value f is 3 or more (in the case of June 28 and 29 of the diagnostic unit 31a), the process proceeds to step S17.

  That is, in step S1, the control unit 62 determines that there is a high possibility that an abnormality has occurred in the diagnostic unit 31a on June 26 (the day when the abnormality occurred in the diagnostic unit 31a) and 27th. Thus, it is not diagnosed that an abnormality has occurred in the diagnostic unit 31a. Then, the controller 62 diagnoses that an abnormality has occurred in the diagnostic unit 31a on June 28 and 29. In FIG. 2, the reason that the control unit 62 does not diagnose that an abnormality has occurred in the diagnostic unit 31 a after June 30 is that the average value J (D) of the past system efficiency is calculated. This is because the system efficiency of the date when the abnormality occurs is used.

  Thereafter, in step S17, the control unit 62 diagnoses that an abnormality has occurred in the solar cell power generation system 30 (diagnosis unit 31a), and the diagnosis result is stored in the storage unit 63, and the process proceeds to step S2.

Step S2 includes steps S21 to S23 as shown in FIG. In step S21, as in step S12, the control unit 62 determines whether or not the amount of solar radiation on the date on which abnormality diagnosis is performed is equal to or greater than a predetermined value (for example, 1.5 [kWh / m ² ]). . If the control unit 62 determines in step S21 that the amount of solar radiation is less than 1.5 [kWh / m ² ], the process proceeds to step S3. On the other hand, when the control unit 62 determines that the amount of solar radiation is 1.5 [kWh / m ² ] or more, the process proceeds to step S22.

In the first embodiment, Step S2 includes Step S21 for determining whether or not the amount of solar radiation is 1.5 [kWh / m ² ] or more. However, Step S21 overlaps with Step S12. May not be provided.

  In step S22, the control unit 62 converts the system efficiency Ja (d) of the diagnostic unit 31 (for example, the diagnostic unit 31a) to be subjected to the abnormality diagnosis into the other diagnostic units 31 (for example, the diagnostic units 31b, 31c, and 31d). It is determined whether or not the value Ma (d) subtracted from the average value JA (d) of the system efficiency is equal to or greater than a predetermined value E2 (for example, 12 [%]). Note that the predetermined value E2 that is a threshold for determination may be a value other than 12 [%].

  For example, in the first embodiment, similarly to the predetermined value E1, when an abnormality occurs in one solar cell string 11 (when one breaker 21 is shut off), the abnormality of the diagnostic unit 31a can be detected. A predetermined value E2 may be set. That is, it is determined whether or not the system efficiency J (d) is equal to or less than the value obtained by multiplying the average value JA (d) of the system efficiency of the other diagnostic units 31b, 31c and 31d by “1-1 / n”. Alternatively, a predetermined value E2 may be set.

  Specifically, since 1/1 / n = 0.75, JA (d) × 0.75 ≧ J (d), and Ma (d) = JA (d) −J (d) ≧ JA (D) × 0.25. Since JA (d) is about 70 [%] to about 81 [%], JA (d) × 0.25 = about 17.5 [%] to about 20.3 [%]. For this reason, the predetermined value E2 that is a threshold for determination may be set to about 17.5 [%] to about 20.3 [%]. In the first embodiment, the predetermined value E2 is set to be smaller than about 17.5 [%] to about 20.3 [%], for example, 12 [%], so that one solar cell string 11 is abnormal. When this occurs, it is possible to reliably detect an abnormality in the diagnostic unit 31.

  In step S22, when the control unit 62 determines that the value Ma (d) is less than a predetermined value E2 (for example, 12 [%]), the process proceeds to step S3. On the other hand, if the control unit 62 determines that the value Ma (d) is equal to or greater than a predetermined value E2 (for example, 12 [%]) (in the case of the diagnostic unit 31a from June 26 to July 2), step Proceed to S23.

  Thereafter, in step S23, the control unit 62 diagnoses that an abnormality has occurred in the diagnosis unit 31a, and the diagnosis result is stored in the storage unit 63, and the process proceeds to step S3.

  Finally, in step S3 (see FIG. 4), the control unit 62 displays the diagnosis result stored in the storage unit 63, for example, on the output unit 60a. At this time, only when it is diagnosed that an abnormality has occurred in the solar cell power generation system 30 (diagnosis unit 31), that effect may be displayed on the output unit 60a, and not only the diagnosis result but also the amount of solar radiation, The amount of power, system efficiency, etc. may be displayed together.

  As described above, the administrator of the solar cell power generation system 30 can be notified of the occurrence of an abnormality in the solar cell power generation system 30. As a result, a repair company or the like is dispatched to the solar cell power generation system 30 in which an abnormality has occurred, and an abnormality occurrence point is investigated or repaired.

  In the first embodiment, as described above, by dividing the power generation amount measured by the power amount detector 22 by the theoretical power generation amount of the diagnostic unit 31 calculated based on the solar radiation amount measured by the solar radiation meter 33, A control unit 62 for calculating the system efficiency of the diagnostic unit 31 is provided. When the power generation amount increases or decreases due to the increase or decrease in the amount of solar radiation, the theoretical power generation amount also increases or decreases, so that the increase or decrease in the ratio of the actual power generation amount to the theoretical power generation amount (system efficiency) can be suppressed. That is, the fluctuation of the ratio of the actual power generation amount to the theoretical power generation amount (system efficiency) can be reduced compared to the fluctuation of the power generation amount due to the weather. Thus, as described above, the control unit 62 performs abnormality diagnosis of the diagnostic unit 31 using the system efficiency, so that the diagnostic unit 31 (solar cell power generation system) is measured using only the power generation amount without measuring the amount of solar radiation. Compared with the case of diagnosing the abnormality of 30), the abnormality of the diagnostic unit 31 (solar cell power generation system 30) can be diagnosed with high accuracy.

  Moreover, in 1st Embodiment, as mentioned above, by arranging the pyranometer 33 around the diagnostic unit 31 and the power conditioner 20, it suppresses that the installation environment of the diagnostic unit 31 and the pyranometer 33 differs. Can do. Thereby, since the solar radiation amount which injects into the diagnostic unit 31 can be calculated easily and accurately, abnormality of the diagnostic unit 31 (solar cell power generation system 30) can be diagnosed easily and accurately.

In the first embodiment, as described above, the control unit 62 does not diagnose that an abnormality has occurred in the diagnostic unit 31 when the amount of solar radiation is less than 1.5 [kWh / m ² ]. Thereby, abnormality of the diagnostic unit 31 (solar cell power generation system 30) can be diagnosed more accurately.

  In the first embodiment, as described above, the control unit 62 determines the system efficiency J (d) of the date d to be diagnosed for abnormality and the average value J (D) of the past system efficiency from the date d. ) Is compared, the abnormality diagnosis of the diagnostic unit 31 is performed. Thereby, the system efficiency (system efficiency J (d) and average value J (D) of past system efficiency) of the same diagnostic unit 31 can be compared to perform abnormality diagnosis, so that the diagnostic unit 31 ( An abnormality of the solar cell power generation system 30) can be diagnosed with higher accuracy.

  In the first embodiment, as described above, the value L (d) obtained by subtracting the system efficiency J (d) from the average value J (D) of the system efficiency is, for example, a predetermined value E1 or more for three consecutive days. In this case, the control unit 62 diagnoses that an abnormality has occurred in the diagnosis unit 31. As a result, when the system efficiency J (d) suddenly decreases for some reason, the control unit 62 makes an erroneous diagnosis that an abnormality has occurred in the diagnostic unit 31 (solar cell power generation system 30). Can be suppressed. Thereby, abnormality of the diagnostic unit 31 (solar cell power generation system 30) can be diagnosed more accurately.

  In the first embodiment, as described above, the value L () obtained by subtracting the system efficiency J (d) from the average value J (D) of the system efficiency three days or more before the date d to be diagnosed for abnormality. When d) is equal to or greater than the predetermined value E1 for three consecutive days, the control unit 62 diagnoses that an abnormality has occurred in the diagnosis unit 31. Accordingly, it is possible to diagnose whether or not an abnormality has occurred in the diagnostic unit 31 using the average value J (D) of the system efficiency before the abnormality has occurred in the diagnostic unit 31. An abnormality of the solar cell power generation system 30) can be diagnosed with higher accuracy.

  In the first embodiment, as described above, the average value J (D) of system efficiency is an average value of system efficiency for a plurality of days (for example, three days). Thereby, since the dispersion | variation in the past system efficiency can be suppressed, abnormality of the diagnostic unit 31 (solar cell power generation system 30) can be diagnosed more accurately.

  In the first embodiment, as described above, the control unit 62 compares the system efficiency Ja (d) of the diagnostic unit 31a with the average value JA (d) of the system efficiencies of the diagnostic units 31b, 31c, and 31d. By doing so, abnormality diagnosis of the diagnostic unit 31a is performed. Thereby, since the diagnostic units 31 under substantially the same installation environment can be compared, abnormality of the diagnostic unit 31 (solar cell power generation system 30) can be diagnosed with high accuracy.

  In the first embodiment, as described above, the storage unit 63 that stores the calculated system efficiency is provided. This is particularly effective because it is not necessary to recalculate the past system efficiency each time an abnormality is diagnosed.

(Second Embodiment)
In the second embodiment of the present invention, a case where a connection box 140 and a current collection box 150 are provided between the solar cell 110 and the power conditioner 20 will be described with reference to FIG. 8, unlike the first embodiment.

  As shown in FIG. 8, the solar cell power generation system 130 according to the second embodiment of the present invention includes a solar cell 110, a connection box 140 to which a plurality of solar cells 110 are electrically connected, and a plurality of connection boxes 140. It includes a current collection box 150 that is electrically connected, a power conditioner 20 to which a plurality of current collection boxes 150 are electrically connected, and a current collector 132 to which a plurality of power conditioners 20 are electrically connected. In FIG. 8, for simplification of the drawing, the solar cell 110, the connection box 140, the current collection box 150, and the power conditioner 20 are illustrated one by one.

  The solar cell 110 includes a plurality of solar cell strings 111.

  Here, in the second embodiment, the solar cell string 111 includes a plurality of solar cell modules 12 connected in series, a plurality of electric energy detectors 112 for measuring the power generation amount of each solar cell module 12, and A power amount detector 113 is included for measuring the power generation amount of the solar cell string 111 (the total power generation amount of the five solar cell modules 12).

  Moreover, in 2nd Embodiment, the breaker 141 which interrupts | blocks a circuit when abnormal current flows is provided in the connection box 140 for every solar cell string 111. FIG. In addition, the connection box 140 is provided with an electric energy detector 142 for measuring the power generation amount of the solar cell 110 connected to the connection box 140.

  In the second embodiment, the current collection box 150 is provided with a breaker 151 for each connection box 140 that shuts off the circuit when an abnormal current flows. In addition, the current collection box 150 is provided with a power amount detector 152 for measuring the total amount of power generated from the plurality of connection boxes 140.

  In the second embodiment, the current collector 132 is provided with a power amount detector 131 for measuring the power generation amount of the entire solar cell power generation system 130 (total power generation amount from the plurality of power conditioners 20). Yes.

  The power amount detectors 112, 113, 131, 142, and 152 have a function of transmitting measured power generation amount data (power generation amount data) to the data collection unit 40, similarly to the power amount detector 22 of the first embodiment. Have. The power amount detectors 112, 113, 131, 142, and 152 are examples of the “power generation amount measuring unit” of the present invention.

  Other structures of the second embodiment are the same as those of the first embodiment.

  In the second embodiment, as described above, by providing the power amount detector 112 for each solar cell module 12, the diagnosis unit can be the solar cell module 12, and abnormality diagnosis can be performed for each solar cell module 12. In this case, the solar battery cell is the “lower layer unit” of the present invention.

  In the second embodiment, as described above, by providing the power amount detector 113 for each solar cell string 111, the diagnostic unit is the solar cell string 111, and abnormality diagnosis is performed for each solar cell string 111. it can. In this case, the solar cell module 12 is the “lower layer unit” of the present invention.

  In the second embodiment, as described above, by providing the electric energy detector 142 for each connection box 140, the diagnosis unit is configured by the connection box 140 and the solar battery 110, and abnormality diagnosis is performed for each connection box 140. It can be carried out. In this case, the solar cell string 111 is the “lower layer unit” of the present invention.

  Further, in the second embodiment, as described above, the diagnostic unit is configured by the current collection box 150, the plurality of connection boxes 140, and the plurality of solar cells 110 by providing the power amount detector 152 for each current collection box 150. In addition, abnormality diagnosis can be performed for each current collection box 150. In this case, the junction box 140 is the “lower layer unit” of the present invention.

  Further, in the second embodiment, similarly to the above embodiment, by providing the power amount detector 22 for each power conditioner 20, the diagnosis unit is the power conditioner 20, the plurality of current collection boxes 150, the plurality of connection boxes 140, and the plurality of solar cells. An abnormality diagnosis can be performed for each power conditioner 20 configured by the battery 110. In this case, the current collection box 150 is the “lower layer unit” of the present invention.

  Further, in the second embodiment, as described above, by providing the power amount detector 131 in the current collector 132, the diagnostic unit is the solar cell power generation system 130 (the current collector 132, the plurality of current collector boxes 150, the plurality of current collectors). The connection box 140 and the plurality of solar cells 110) can be used to diagnose abnormality of the solar cell power generation system 130. In this case, the power conditioner 20 is the “lower layer unit” of the present invention.

  Other effects of the second embodiment are the same as those of the first embodiment.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above embodiment, an example in which abnormality diagnosis is performed using the ratio (system efficiency) obtained by dividing the actually measured power generation amount by the theoretical power generation amount has been described. Needless to say, the theoretical power generation amount is divided by the actually measured power generation amount. An abnormality diagnosis may be performed using the ratio (the reciprocal of the system efficiency). In this case, in steps S13 and S22, the control unit may determine whether or not the values L (d) and Ma (d) are equal to or less than a predetermined value.

  Similarly, in the above embodiment, the value L (d) is calculated by subtracting the system efficiency J (d) from the average value J (D) of the past system efficiency, and the average value of the system efficiency of other diagnostic units is calculated. The example in which the value Ma (d) is calculated by subtracting the system efficiency Ja (d) from JA (d) has been described. Needless to say, the average value J (D of the past system efficiency is calculated from the system efficiency J (d). ) Is calculated to calculate the value L (d), and the system efficiency Ja (d) is subtracted from the average value JA (d) of the system efficiency of other diagnostic units to calculate the value Ma (d). Also good. In this case, in steps S13 and S22, the control unit may determine whether or not the values L (d) and Ma (d) are equal to or less than a predetermined value.

  Further, in the above embodiment, whether or not an abnormality has occurred is determined by comparing the system efficiency between step S1 for diagnosing the presence or absence of an abnormality in the diagnostic unit 31 alone using the past data and the other diagnostic units 31. However, the present invention is not limited to this, and the present invention is not limited to this. Step S1 for diagnosing the occurrence of abnormality in the diagnostic unit 31 alone using past data, and other diagnostic units Only one of the steps S <b> 2 for diagnosing whether or not an abnormality has occurred may be provided by comparing the system efficiency with the system 31. If the control unit is configured so as to diagnose the occurrence of abnormality in the diagnostic unit 31 alone using the past data, even if there is no other diagnostic unit other than the diagnostic unit that is the target of abnormality diagnosis The abnormality of the diagnostic unit (solar cell power generation system) can be diagnosed.

  In the above embodiment, the example in which the process of step S2 is performed even when it is diagnosed that an abnormality has occurred in step S1 has been described. However, the present invention is not limited to this, and an abnormality occurs in step S1. If it is diagnosed that it is, the process may proceed to step S3 without performing step S2.

  In the above embodiment, an example in which abnormality diagnosis is performed in units of one day has been described. However, the present invention is not limited to this, and may be performed in units of one month, one week, or one hour.

  Moreover, in the said embodiment, although the example which provided the control part which performs a calculation and a diagnosis in the management server was shown, this invention is not restricted to this, For example, a power supply etc. of a solar cell power generation system perform a calculation and a diagnosis. A control unit may be provided.

  In the above-described embodiment, an example in which the control unit is configured to perform calculation and diagnosis has been described. However, the present invention is not limited thereto, and the calculation unit that performs calculation and the diagnosis unit that performs diagnosis are separately provided. It may be provided. In this case, for example, a calculation unit may be provided in the solar cell power generation system, and a diagnosis unit may be provided in the management server.

In the above-described embodiment, the example in which the threshold (predetermined value) for determining the amount of solar radiation is 1.5 [kWh / m ² ] has been described. However, the present invention is not limited to this, and the threshold for determining the amount of solar radiation. The (predetermined value) may be set to, for example, 1.75 [kWh / m ² ] or may be set to other values.

  In the above embodiment, the control unit determines whether or not a value L (d) obtained by subtracting the system efficiency J (d) from the average value J (D) of the past system efficiency is equal to or greater than a predetermined value. However, the present invention is not limited to this, and it is determined whether or not a value obtained by dividing the average value J (D) of the past system efficiency by the system efficiency J (d) is a predetermined value or more. As such, the control unit may be configured. In this case, the determination threshold (predetermined value) may be set to about 1.2, for example. For example, in the configuration of the first embodiment, when the threshold value (predetermined value) for determination is 1.2, if an abnormality occurs in any of the four solar cell strings, the solar cell string (diagnostic unit) It is possible to reliably detect abnormalities.

  In the above embodiment, the value Ma (d) obtained by subtracting the system efficiency Ja (d) of the diagnostic unit to be diagnosed from the average value JA (d) of the system efficiency of other diagnostic units is a predetermined value or more. Although an example in which the control unit is configured to determine whether or not there is an example is shown, the present invention is not limited to this, and the average value JA (d) of the system efficiency of other diagnostic units is determined as the system efficiency Ja (d). The control unit may be configured to determine whether or not the value divided by is greater than or equal to a predetermined value. In this case, the determination threshold (predetermined value) may be set to about 1.2, for example. For example, in the configuration of the first embodiment, when the threshold value (predetermined value) for determination is 1.2, if an abnormality occurs in any of the four solar cell strings, the solar cell string (diagnostic unit) It is possible to reliably detect abnormalities.

  In the above embodiment, the case where p = 3 is calculated when calculating the average value J (D) of the past system efficiency. However, the present invention is not limited to this, and p is set to a value other than 3. May be. For example, if p = 365, p = 730 (= 365 × 2), etc., the calculated system efficiency J (d) can be compared with the system efficiency of about one year ago or about two years ago. As a result, even when the diagnostic unit deteriorates over time and the system efficiency of the diagnostic unit gradually decreases as shown in FIG. 9, the control unit can detect the aged deterioration (abnormality) of the diagnostic unit.

  In the above embodiment, the control is performed so as to determine whether or not a value L (d) obtained by subtracting the system efficiency J (d) from the average value J (D) of the past system efficiency is equal to or greater than the predetermined value E1. However, the present invention is not limited to this, and the control unit also determines whether the value L (d) is equal to or less than a predetermined value, and the value L (d) is a predetermined value (for example, -10 [%]) or less, it may be configured to diagnose that an abnormality has occurred in the pyranometer. With this configuration, even if the system efficiency of the diagnostic unit becomes high as shown in FIG. 10 or FIG. The abnormality of the pyranometer can be detected by the unit. Similarly, if the value obtained by dividing the average value J (D) of the past system efficiency by the system efficiency J (d) is a predetermined value (for example, 0.8) or less, an abnormality has occurred in the pyranometer. The controller may be configured to determine.

  In the above embodiment, when determining whether or not an abnormality has occurred in a single diagnostic unit using past data, an example of using an average value of system efficiency for a plurality of past days (for example, three days) is shown. The present invention is not limited to this, and an average value of system efficiencies in the past one day may be used.

  In addition, an average value of the system efficiencies for a plurality of days may be used as the system efficiency J (d) of the date on which the abnormality is diagnosed.

  Moreover, although the said embodiment demonstrated the example in which the several power conditioner was electrically connected to the current collector, this invention is not restricted to this, It is not necessary to provide a current collector. That is, the power conditioner may be electrically connected to the commercial power system or the load of the facility without going through the current collector.

1 Solar cell abnormality diagnosis system 11 Solar cell string (lower layer unit)
12 Solar cell module 22, 112, 113, 131, 142, 152 Electric energy detector (power generation measuring unit)
30 Solar power generation system 31 Diagnostic unit 31a Diagnostic unit (first diagnostic unit)
31b, 31c, 31d Diagnostic unit (second diagnostic unit)
33 Pyrometer 62 Control unit (calculation unit, diagnosis unit)
63 Storage unit E1, E3 Predetermined value J (d) System efficiency (ratio of first period, ratio of first diagnostic unit)
J (D) Average system efficiency (ratio of second period)
JA (d) Average system efficiency (ratio of second diagnostic unit)
L (d) Reduced value

Claims (21)

A solar cell power generation system including a diagnostic unit having a solar cell module, a power generation amount measuring unit for measuring the power generation amount of the diagnostic unit, and a solar radiation meter for measuring solar radiation amount
A power generation amount measured by the power generation amount measurement unit, and a calculation unit that calculates a ratio of the theoretical power generation amount of the diagnostic unit calculated based on the solar radiation amount measured by the pyranometer,
A solar cell abnormality diagnosis system comprising: a diagnosis unit that performs abnormality diagnosis of the diagnosis unit using the calculated ratio.   2. The solar cell abnormality diagnosis system according to claim 1, wherein when the amount of solar radiation is less than a predetermined value, the diagnosis unit does not diagnose that an abnormality has occurred in the diagnosis unit.   2. The diagnosis unit performs an abnormality diagnosis of the diagnosis unit by comparing the ratio of the first period and the ratio of the second period that is earlier than the first period. Or the solar cell abnormality diagnosis system of 2 or 2.   The solar cell abnormality diagnosis system according to claim 3, wherein the ratio is a value obtained by dividing the power generation amount measured by the power generation amount measurement unit by the theoretical power generation amount.   The value obtained by subtracting the ratio of the first period from the ratio of the second period or the value obtained by dividing the ratio of the second period by the ratio of the first period is a predetermined value or more continuously for a predetermined number of times. Furthermore, the said diagnostic part diagnoses that abnormality has generate | occur | produced in the said diagnostic unit, The solar cell abnormality diagnostic system of Claim 4 characterized by the above-mentioned. The second period is a period p days or more before the first period,
When the subtracted value or the subtracted value is equal to or greater than a predetermined value for q days consecutively less than or equal to p days, the diagnostic unit diagnoses that an abnormality has occurred in the diagnostic unit. The solar cell abnormality diagnosis system according to claim 5, wherein: The diagnostic unit is composed of n lower layer units,
When the ratio of the first period is equal to or less than a value obtained by multiplying the ratio of the second period by “1-1 / n”, the diagnosis unit diagnoses that an abnormality has occurred in the diagnosis unit. The solar cell abnormality diagnosis system according to any one of claims 4 to 6, wherein:   When the value obtained by subtracting the ratio of the first period from the ratio of the second period or the value obtained by dividing the ratio of the second period by the ratio of the first period is equal to or less than a predetermined value, the diagnosis unit The solar cell abnormality diagnosis system according to any one of claims 4 to 7, wherein an abnormality is generated in the pyranometer.   The solar cell abnormality diagnosis system according to claim 3, wherein the ratio of the second period is an average value of the ratios for a plurality of days. The diagnostic unit includes a first diagnostic unit and a second diagnostic unit;
The diagnosis unit performs an abnormality diagnosis of the first diagnosis unit by comparing the ratio of the first diagnosis unit with the ratio of the second diagnosis unit. The solar cell abnormality diagnosis system according to any one of the above. The solar cell abnormality diagnosis system according to claim 10, wherein the ratio is a value obtained by dividing the power generation amount measured by the power generation amount measurement unit by the theoretical power generation amount.
The first diagnostic unit is composed of n lower layer units,
When the ratio of the first diagnosis unit is equal to or less than a value obtained by multiplying the ratio of the second diagnosis unit by “1-1 / n”, the diagnosis unit generates an abnormality in the first diagnosis unit. The solar cell abnormality diagnosis system according to claim 11, wherein the solar cell abnormality diagnosis system is diagnosed. The solar cell according to claim 2, wherein the diagnostic unit does not diagnose that an abnormality has occurred in the diagnostic unit when the amount of solar radiation is less than 1.5 [kWh / m ² ]. Abnormality diagnosis system.   The solar cell abnormality diagnosis system according to claim 1, wherein the diagnostic unit is the solar cell module.   The solar cell abnormality diagnosis system according to claim 1, further comprising a storage unit that stores the calculated ratio. Calculate the ratio of the theoretical power generation amount of the diagnostic unit calculated based on the power generation amount of the diagnostic unit having the solar cell module and the solar radiation amount measured by the solar meter provided in the solar cell power generation system including the diagnostic unit. An arithmetic unit to perform,
A solar cell abnormality diagnosis device comprising: a diagnosis unit that performs abnormality diagnosis of the diagnosis unit using the calculated ratio.   The solar cell abnormality diagnosis apparatus according to claim 16, wherein the diagnosis unit does not diagnose that an abnormality has occurred in the diagnosis unit when the amount of solar radiation is less than a predetermined value. Measuring a power generation amount of a diagnostic unit having a solar cell module;
A step of measuring the amount of solar radiation by a solar meter provided in a solar cell power generation system including the diagnostic unit;
Calculating a theoretical power generation amount of the diagnostic unit based on the measured solar radiation amount;
Calculating a ratio of the measured power generation amount and the calculated theoretical power generation amount;
And a step of performing an abnormality diagnosis of the diagnostic unit using the calculated ratio.   The step of performing an abnormality diagnosis of the diagnostic unit includes a step of not diagnosing that an abnormality has occurred in the diagnostic unit when the amount of solar radiation is less than a predetermined value. Solar cell abnormality diagnosis method.   The step of diagnosing abnormality of the diagnostic unit includes the step of diagnosing abnormality of the diagnostic unit by comparing the ratio of the first period with the ratio of the second period that is earlier than the first period. The solar cell abnormality diagnosis method according to claim 18 or 19, characterized by comprising: The diagnostic unit includes a first diagnostic unit and a second diagnostic unit;
The step of performing abnormality diagnosis of the diagnostic unit includes the step of performing abnormality diagnosis of the first diagnostic unit by comparing the ratio of the first diagnostic unit with the ratio of the second diagnostic unit. The solar cell abnormality diagnosis method according to any one of claims 18 to 20, wherein:

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