WO2016166992A1 - Abnormality monitoring system and program - Google Patents

Abstract

In order to determine a suitable reference value for monitoring abnormalities in a device, an abnormality monitoring device (10) is provided with a data acquisition interface (11) that acquires electrical output values that correspond to solar radiation intensity and with a monitoring unit (12). The monitoring unit (12) is provided with a calculation unit (121) that calculates average rates of change from two electrical output values from the interface (11) for every prescribed extraction period, with a filter unit (122) that extracts an electric power value for an average rate of change if the average rate of change is within a prescribed allowable range, and with a storage unit (123). The allowable range is among a plurality of allowable ranges for different times of a day and corresponds to a time. Each allowable range includes a reference rate of change, and the plurality of reference rates of change for the plurality of allowable ranges are an average rate of change for one clear sky day. The storage unit (123) stores extracted electrical output values as reference values together with corresponding time information.

Description

Abnormality monitoring system and program

The present invention relates to an abnormality monitoring system and program.

Conventionally, a technique for determining whether the output of a solar cell is normal or abnormal based on the electric output of the solar cell is known (see, for example, Patent Document 1). In Patent Document 1, a ratio of an actual output power value of a solar cell at a predetermined sunshine time to a standard output power value corresponding to the sunshine time is calculated, and whether the output of the solar cell is normal or abnormal based on this ratio Is judged. In Patent Document 1, the power value at a predetermined sunshine time for a plurality of solar cell arrays, or the maximum value of the output power value of the solar cell array repeatedly measured at each sunshine time over a plurality of days is set as the standard output power value. Is described.

The invention described in Patent Document 1 diagnoses whether or not the solar cell array is properly installed at the time of introduction of the solar power generation facility, and diagnoses deterioration or failure of the power generation capability due to the temporal change of the solar cell array. Therefore, the standard output power value of the solar cell is used.

However, since the output power value of the solar cell array changes due to the influence of the solar altitude due to the season, there is a possibility that the standard output power value described in Patent Document 1 cannot be used throughout the year. In addition, when the maximum output power value is set as the standard output power value, the standard output power value is affected by the influence of solar radiation or cloud shadows. It is difficult to determine a standard output power value as a reference.

JP 2005-340464 A

An object of the present invention is to provide an anomaly monitoring system that can determine an appropriate reference value for monitoring an anomaly of an apparatus. Another object of the present invention is to provide a program that causes a computer to function as the abnormality monitoring system.

The present disclosure relates to an abnormality monitoring system configured to monitor an abnormality of a device based on an electrical output of the device. The abnormality monitoring system according to the present invention includes a data acquisition interface and a monitoring unit. The data acquisition interface is configured to acquire the value of the electrical output for each time of day from a device that outputs the electrical output corresponding to the solar radiation intensity. The monitoring unit monitors the presence or absence of abnormality of the device by comparing the value of the electrical output for each time of day from the data acquisition interface with the corresponding reference value among the reference values for the time of day. Configured to do. The apparatus includes at least one of a solar cell and a pyranometer. The monitoring unit includes a calculation unit, a filter unit, and a storage unit. The calculation unit calculates an average rate of change from the value of the electrical output corresponding to the time at both ends of the extraction time and the extraction time for each predetermined extraction time based on the value of the electrical output from the data acquisition interface. Configured to calculate. The filter unit is configured to extract an electrical output value having an average rate of change within a predetermined allowable range from the average rate of change for each extraction time from the calculation unit. Here, the permissible range is a permissible time range among a plurality of permissible ranges for each time of day, each of the plurality of permissible ranges is a range including a standard change rate, The plurality of standard change rates in the plurality of allowable ranges are average change rates for one day corresponding to a sunny day. The storage unit is configured to store the value of the electrical output extracted by the filter unit as the reference value together with corresponding time information.

This disclosure relates to a program for causing a computer to function as the abnormality monitoring system. A program according to the present invention causes a computer to function as the above-described abnormality monitoring system.

According to the configuration of the present invention, there is an advantage that it is possible to set an appropriate reference value for monitoring an apparatus abnormality.

The drawings illustrate one or more embodiments in accordance with the present disclosure, but are by way of example and not limitation. In the drawings, like numerals refer to the same or similar elements.
It is a block diagram which shows embodiment. It is explanatory drawing of the extraction time of embodiment, a sampling period, and a sampling period (sampling period). 3A to 3C are graphs showing how the average rate of change for each of extraction time 1 minute, extraction time 7 minutes, and extraction time 30 minutes changes with time. It is a graph which shows how the value (for example, illumination intensity) of the output pattern in an embodiment changes with time. It is a graph which shows how a standard change rate and the tolerance | permissible_range with respect to this change with time in embodiment. 6A is a graph showing a time change of an ideal output pattern in the embodiment, FIG. 6B is a graph showing a time change of a change rate pattern obtained from the ideal output pattern in the embodiment, and FIG. 6C is an actually measured value in the embodiment. 6D is a graph showing the time change of the change rate pattern obtained from the output pattern of the actual measurement value in the embodiment, and FIG. 6E is the time of the reference value pattern obtained from the actual measurement value in the embodiment. It is a graph which shows a change. 7A to 7C are graphs showing temporal changes in reference value patterns generated from different daily power values, and FIG. 7D is a temporal change in reference value patterns generated by superimposing different multiple day power values. It is a graph which shows. FIG. 8A is a graph showing a power value and a change with time of an allowable range for extracting a reference value from the power value in the embodiment, and FIG. 8B is a graph showing a change with time of the allowable range in an iterative process with respect to the reference value in the embodiment. It is a graph which shows.

The anomaly monitoring system described below is configured to monitor anomalies for medium to large-scale photovoltaic power generation facilities. The abnormality monitoring system according to each embodiment of the present disclosure may be a single device, or may be configured to distribute any of its own functions to a plurality of devices. Hereinafter, the abnormality monitoring system is referred to as an “abnormality monitoring apparatus”. The power generation scale of the solar power generation facility is not particularly limited, but the solar power generation facility to which the abnormality monitoring apparatus described below is applied assumes a power generation scale of several hundred or more solar panels. . For example, if the power generation scale is about 250 kW, 1000 or more solar cell panels are arranged, and if the power generation scale is about 1 MW, the installation area of the solar cell panel is about 1 ha. However, the technology described below can be applied to a small-scale photovoltaic power generation facility of about several kW for home use or the like.

The solar power generation facility includes a solar cell and a power conversion device for converting DC power output from the solar cell into AC power regardless of the power generation scale. The power converter is a so-called power conditioner. Moreover, the photovoltaic power generation facility described below includes a pyranometer and a power receiving / transforming facility having a function of supplying AC power generated by the power converter to the power system. The pyranometer is configured to measure the solar radiation intensity on the solar cell. For example, the pyranometer is arranged adjacent to the solar cell at the same angle as the inclination angle of the solar cell.

The abnormality monitoring device monitors the presence or absence of abnormality such as deterioration or failure of the device 2 based on the electrical output of at least one of the solar cell and the pyranometer (hereinafter referred to as “device 2” (see FIG. 1)). For example, the presence / absence of abnormality of the solar cell is mainly monitored, but the presence / absence of abnormality of the pyranometer can also be monitored. In order to determine whether or not the device 2 is abnormal based on the electrical output of the device 2, the abnormality monitoring device determines a reference value corresponding to the value of the electrical output in an environment that can be regarded as a clear sky, and the measured electrical output The presence or absence of an abnormality in the device 2 is determined by comparing the value of the value and the reference value. The value of the electric output from the device 2 varies depending on the solar radiation intensity, and also varies depending on the incident angle of the solar radiation on the device 2. Therefore, it changes with conditions, such as a weather, a season, and the time of the day. Moreover, the surrounding environment of the installation place of the apparatus 2, that is, the surrounding terrain, the surrounding buildings, the surrounding trees, and the like also cause the value of the electric output from the apparatus 2 to change.

A solar cell is composed of a plurality of modules (solar power generation panels) connected in series to form a string. A plurality of strings are connected to the junction box, and the plurality of strings constitute a solar cell array. The junction box has a string monitor and monitors the current output by each string. The DC power output from the solar cell (solar cell array) is supplied to the power converter through the connection box. The photovoltaic power generation facility includes a measurement device that monitors the input voltage of the power conversion device. The measuring device also has a function of acquiring a current value for each string monitored by the string monitor. The electric power generated by the solar cell can be obtained from the current value monitored by the string monitor and the voltage value monitored by the measuring device. The string monitor may be configured not only to monitor the current output from each string but also to monitor the output voltage of the string.

The abnormality monitoring device monitors the current value or power value output from the solar cell as an electrical output reflecting the solar radiation intensity irradiated to the solar cell when monitoring an abnormality such as deterioration or failure of the solar cell. Moreover, when monitoring an abnormality such as deterioration or failure of the pyranometer, the abnormality monitoring device performs monitoring based on the electric output of the pyranometer disposed adjacent to the solar cell.

The abnormality monitoring device can monitor the entire solar cell collectively when monitoring the abnormality of the solar cell. However, if monitoring is performed in units of strings, a plurality of modules constituting the photovoltaic power generation facility can be monitored. It becomes possible to manage by dividing into multiple. For example, when an abnormality is detected in one of the strings, the work to find out the location where the abnormality occurred can be narrowed down to the range of modules that make up the corresponding string, and the response to the abnormality can be made quickly. Is possible.

Here, the abnormality monitoring device only needs to be configured to store data necessary for determining an abnormality such as a deterioration or failure of the device 2, and whether or not the device 2 has an abnormality can be determined. You may make it perform by the judgment apparatus different from an abnormality monitoring apparatus. For example, it may be configured such that the determination as to whether or not there is an abnormality in the apparatus 2 is automatically performed as a determination apparatus by a remote diagnosis server that communicates with the abnormality monitoring apparatus through a communication line such as the Internet. Moreover, based on the data from the abnormality monitoring device collected by the cloud computing system, the administrator of the photovoltaic power generation facility may determine the abnormality of the solar cell with a terminal device as a determination device. Of course, the abnormality monitoring apparatus may be configured to also serve as a determination apparatus that determines whether or not the apparatus 2 has an abnormality.

In addition, in the following, a configuration in which operation states of a plurality of photovoltaic power generation facilities are aggregated and monitored in an abnormality monitoring apparatus will be described as an example. However, operation states of a plurality of photovoltaic power generation facilities are associated with each of the photovoltaic power generation facilities. A configuration may be adopted in which the terminal device transmits data from the abnormality monitoring device. That is, it is possible to employ either a configuration in which operation status monitoring is performed on a plurality of photovoltaic power generation facilities in a centralized manner or a configuration that is performed in a distributed manner at a plurality of locations. In short, if there is an environment in which the data of electrical output generated by the photovoltaic power generation facility can be acquired by the abnormality monitoring device through the telecommunication line, the presence or absence of abnormality in the photovoltaic power generation facility is monitored regardless of the location of the abnormality monitoring device. Is possible.

The anomaly monitoring device is used by a business operator that uses a solar power generation facility, an EPC (Engineering, Procurement and Construction) contractor commissioned by a power generation business operator, or a maintenance business operator of a solar power generation facility. For example, the number of sites of the photovoltaic power generation facility monitored by one abnormality monitoring device is assumed to be 100 to 500 sites. However, the number of sites of solar power generation facilities that can be monitored can be increased as necessary by increasing the number of abnormality monitoring devices or increasing the processing capacity of the abnormality monitoring devices.

By the way, the figure which arranged the value of the electric output from the device 2 on a clear day along the time axis is almost similar throughout the year if we look at the global view ignoring the change in details. Yes. Hereinafter, a figure in which the values of the electrical output from the device 2 are arranged along the time axis is referred to as an “output pattern”. Furthermore, based on the premise of the installation location and installation conditions of the photovoltaic power generation facilities, even if the output pattern is on a different day, the knowledge that it overlaps almost on a clear day except for the morning and evening time zones is obtained. Yes. For example, if the installation location of the photovoltaic power generation facility is determined, and the installation conditions are such that the solar cell module faces southward and the inclination angle is 30 degrees, the output patterns on a sunny day almost overlap.

According to these findings, the reference value for determining the presence or absence of an abnormality in the device 2 can be used throughout the year only by determining a predetermined time zone in one day corresponding to a sunny day. Of course, the value of the electric output from the device 2 varies depending on the difference in solar altitude according to the season. However, since the change of the output pattern on a sunny day is relatively small depending on the season, the same reference value can be used throughout the year if a correction value corresponding to the season is added to or subtracted from the reference value.

The reference value is determined for each type of device 2, and since a solar cell and a pyranometer are assumed as the device 2 here, it is necessary to set a reference value for the solar cell and a reference value for the pyranometer. is there. Since the solar cell monitors the presence or absence of abnormality with the string (solar panel) as the minimum unit, the reference value is determined so as to be compared with the value of the electric output with the string as the unit. In addition, the reference value to be compared with the electric output value for the solar cell array, the reference value to be compared with the electric output value for the power conditioner, the reference value to be compared with the electric output value for the photovoltaic power generation facility, etc. Determined. The reference value is not limited to the example described above, and can be determined for an appropriate location of the photovoltaic power generation facility.

Hereinafter, a case where the device 2 is a solar cell and a reference value to be compared with the value of the electric output from the string will be described as an example. That is, the case where the device 2 is a solar cell and the reference value for the value of the electric output from the string is set will be described as an example. The electrical output from the string is sampled at a predetermined sampling period. The value of the sampled electrical output changes with time. Therefore, the reference value is set for each time when the electrical output is sampled. Hereinafter, a figure in which the reference values are arranged along the time axis is referred to as a “reference value pattern”.

For example, in the configuration example described below, the sampling period is 1 minute, and the time zone for determining the reference value is from 10:00 to 13:00. In this example, the reference values are determined every minute such as 10:00, 10:00,..., 13:00, and a total of 181 reference values are determined. In addition, the value of the electrical output is obtained as an integrated value or an average value of a plurality of electrical outputs in a sampling period (sampling period) within each sampling period for each sampling period. Similarly, the reference value is obtained as an integrated value or an average value of a plurality of electrical outputs in the sampling period.

By the way, the value of the electric output from the solar cell is ideally changed smoothly on a sunny day, but in reality, even on a sunny day, it depends on the cloud condition or the surrounding environment of the solar cell. It fluctuates greatly. That is, the output pattern on a sunny day is ideally a bell shape, but the measured value of the electrical output from the solar cell is as if the component that changes in a short time overlaps the bell type output pattern. Often complex output patterns. In other words, the output pattern obtained from the actual measurement value often has a shape in which a high-frequency component is superimposed on a unimodal fundamental wave. Hereinafter, the component corresponding to the fundamental wave in the output pattern is referred to as “basic pattern”, and the component corresponding to the high frequency component is referred to as “superimposition pattern”. On a sunny day, the output pattern based on the actual measurement value of the electrical output from the solar cell is usually a combination of the basic pattern and the superimposed pattern.

In the embodiment described below, a technique for generating a reference value pattern in which the influence of the state of the cloud or the surrounding environment of the solar cell is removed while being mainly based on the actual measurement value of the electric output from the solar cell will be described. . Hereinafter, a case where the electrical output is a current will be described. However, the electrical output may be electric power.

(Embodiment)
As shown in FIG. 1, the abnormality monitoring device 10 is configured to receive data from the photovoltaic power generation facility 20 through the electric communication line 31. The telecommunication line 31 is selected from a VPN (Virtual Private Network) using the Internet, a mobile communication network, a dedicated line, or the like. Further, the abnormality monitoring device 10 functions as a computer server that communicates with a terminal device 32 managed by a business operator that performs operation management or maintenance inspection management of the photovoltaic power generation facility 20. That is, the abnormality monitoring device 10 constructs an abnormality monitoring system together with the terminal device 32. In FIG. 1, a solid line represents a power path, and a broken line represents a signal path.

A solar power generation facility 20 shown in FIG. 1 includes, in addition to the solar cell 21, a power conversion device 24 configured to convert DC power output from the solar cell 21 into AC power, and a solar radiation meter 25.

The solar radiation meter 25 is configured to measure the solar radiation intensity to the solar cell 21 (strictly, the solar radiation intensity corresponding to the solar radiation intensity to the solar cell 21). For example, the pyranometer 25 is disposed adjacent to the solar cell 21. As a specific example, the solar radiation meter 25 may be an all solar radiation meter configured to measure the solar radiation intensity to the solar cell 21 to obtain the total solar radiation amount.

Although not provided in the present embodiment, in the solar power generation facility 20, a thermometer may be arranged in addition to the pyranometer 25. Further, the photovoltaic power generation facility 20 includes a power receiving / transforming facility 26 that supplies AC power generated by the power converter 24 to the power system 27. The solar cell 21 is composed of one or a plurality of solar panels (or strings). In the example of FIG. 1, the solar cell 21 is composed of a plurality of strings 211, and the electric output of each of the strings 211 is monitored by a string monitor 221.

The connection box 22 stores, for example, a plurality of string monitors 221 that are electrically connected to each of the plurality of strings 211 constituting one solar cell array. In the present embodiment, the photovoltaic power generation facility 20 includes a plurality of connection boxes 22, and a plurality of strings 211 are connected to each connection box 22. Therefore, the number of string monitors 221 corresponding to the number of the plurality of strings 211 to be connected is accommodated in one connection box 22. The string monitor 221 may be provided separately from the connection box 22. The connection box 22 is configured to collect the DC power output from the string 211 and supply it to the power converter 24. The string monitor 221 is configured to measure the current from the corresponding string 211 through a current sensor. As the current sensor, a configuration in which a Hall element or a magnetoresistive element is attached to a magnetic core is used. The current measurement may be performed through a shunt resistor.

The photovoltaic power generation facility 20 includes a measuring device 23 configured to monitor (measure) an input voltage to the power conversion device 24. The measuring device 23 has a function of acquiring a current value output from each of the strings 211 from the string monitor 221 and a function of acquiring an electric output value of the pyranometer 25. The pyranometer 25 may be connected to the power conversion device 24, and the measurement device 23 may acquire the value of the electric output of the pyranometer 25 via the power conversion device 24. When the string monitor 221 can measure the voltage output from the string 211 together with the current, the measuring device 23 may obtain the power value based on the current value and the voltage value.

The measuring device 23 further includes a communication unit 231 for communicating with the abnormality monitoring device 10 through the electric communication line 31 described above. Although the abnormality monitoring device 10 can monitor at least one of the electric output of the solar cell 21 and the electric output of the pyranometer 25, below, the abnormality of the solar cell 21 is based on the electric output of the solar cell 21. A case where the presence / absence of monitoring is monitored will be described. The technique for monitoring the presence or absence of abnormality of the pyranometer 25 based on the electric output of the pyranometer 25 can be realized by replacing the electric output of the solar cell 21 with the electric output of the pyranometer 25 in the following description. .

The abnormality monitoring apparatus 10 illustrated in FIG. 1 includes a data acquisition interface 11 configured to acquire an electrical output for each string 211 constituting the solar cell 21, and an electrical output acquired by the data acquisition interface 11 (in the present embodiment). A monitoring unit 12 configured to monitor whether or not the solar cell 21 is abnormal by comparing a power value obtained from a current value and a voltage value) with a reference value. That is, the abnormality monitoring device 10 acquires, as the electrical output of the solar cell 21, the current value for each string 211 and the voltage value input to the power conversion device 24 through the electrical communication line 31 from the measurement device 23 described above. The power value generated for each string 211 is obtained. If there is no abnormality in the string 211, this power value has a predetermined relationship with the value of the solar radiation intensity received by the string 211. The abnormality monitoring device 10 may be configured to receive power value data from the measuring device 23 instead of receiving the current value and voltage value data from the measuring device 23. That is, the measurement device 23 may be configured to calculate the power value from the current value and the power value.

In short, in the present embodiment, the measuring device 23 acquires electrical output data (first data) of the solar cell 21 and supplies the data to the abnormality monitoring device 10 (data acquisition interface 11) through the communication unit 231. Configured to do. Here, the first data includes, for example, a power value or a current value and a voltage value for obtaining the power value.

Similarly, when the device 2 is a pyranometer 25, the measuring device 23 acquires electrical output data (second data) of the pyranometer 25, and transmits the data to the abnormality monitoring device 10 (data) via the communication unit 231. Configured to be supplied to an acquisition interface 11). Here, the second data includes the solar radiation intensity value when the solar radiation meter 25 is configured to output the solar radiation intensity value obtained from the solar radiation intensity, and the solar radiation meter 25 measures the solar radiation intensity to measure the solar radiation amount ( For example, when it is configured to obtain the total solar radiation amount), the solar radiation amount obtained from the solar radiation intensity is included. In short, the second data includes a value related to solar radiation intensity.

In order to monitor the presence or absence of abnormality of the solar cell 21 in the abnormality monitoring device 10, the electrical output (power value in the present embodiment) of the solar cell 21 is compared with the reference value at the same time on different days, and the reference value is compared. The power value is determined to be within a predetermined normal range. Even if the power value deviates from a predetermined normal range with respect to the reference value, the monitoring unit 12 does not immediately determine that the power value is abnormal, but the power value is within the normal range with respect to the reference value for one day, for example. It is desirable to determine that an abnormality occurs when the percentage of deviation from 80 is 80% or more. In addition, the numerical value of the ratio determined to be abnormal is an example and can be determined as appropriate.

As shown in FIG. 2, the data acquisition interface 11 is configured to acquire the electrical output of each of the plurality of strings 211 constituting the solar cell 21 for each constant sampling period 101. The sampling period can be selected from the range of about 30 seconds to 10 minutes, but is preferably set to 1 minute, for example. The data acquisition interface 11 is configured to output the integrated value (or average value) of the electrical output in the sampling period (sampling period) 102 for each sampling period 101 to the monitoring unit 12. The abnormality monitoring device 10 includes a built-in clock 13 such as a real time clock in order to measure the date and time and to determine the sampling period.

In short, as shown in the example of FIG. 2, a sampling period (sampling period) 102 for obtaining the values of a plurality of electrical outputs of the solar cell 21 for each sampling period 101 is provided in each sampling period 101. Yes. In this case, since both ends of each sampling period 101 are sampling points, values in the sampling period 102 immediately before the sampling point are acquired for each sampling point. Hereinafter, this configuration is referred to as “configuration A”. Note that the present embodiment is not limited to this configuration A. For example, the present embodiment may have a configuration in which the sampling period 102 is not provided in each sampling period 101 (hereinafter referred to as “configuration B”).

Therefore, in the present embodiment, the data acquisition interface 11 is configured to acquire the first data and supply the first data to the monitoring unit 12 for each sampling period 101. In the configuration A, the first data for each sampling period 101 to the monitoring unit 12 is an integrated value or an average value of a plurality of power values, which are a plurality of power values obtained in the corresponding sampling period 102, Alternatively, it is obtained from a plurality of current values and a plurality of voltage values for obtaining a plurality of power values. In the configuration B, the first data for each sampling period 101 to the monitoring unit 12 includes a power value obtained at the time of sampling.

Similarly, when the device 2 is the pyranometer 25, the data acquisition interface 11 is configured to acquire the second data and supply the second data to the monitoring unit 12 for each sampling period 101. . In the configuration A, the second data for each sampling period 101 to the monitoring unit 12 is an integrated value or an average value of values related to a plurality of solar radiation intensities, and this is a plurality of solar radiations obtained in the corresponding sampling period 102. Obtained from values related to strength. In the configuration B, the second data for each sampling period 101 to the monitoring unit 12 includes a value related to the solar radiation intensity obtained at the time of sampling. As described above, the value relating to the solar radiation intensity is the solar radiation intensity value or the solar radiation amount obtained from the solar radiation intensity value, the integrated value is obtained from a plurality of solar radiation intensity values, and the average value is a plurality of solar radiation intensity values. Obtained from value or multiple solar radiation. The sampling interval in the sampling period 102 is controlled by, for example, a timer (built-in clock 13).

The monitoring unit 12 monitors whether or not the photovoltaic power generation facility 20 has an abnormality, and when an abnormality is detected, notifies the terminal device 32 through the communication interface 14 by a push method. For example, an alarm signal is transmitted to the terminal device 32 through the communication interface 14. The terminal device 32 is a client for the abnormality monitoring device 10 that is a server, and a personal computer that communicates with the abnormality monitoring device 10 is generally used. For communication between the abnormality monitoring device 10 and the terminal device 32, a communication path selected from a VPN (Virtual Private Network) using the Internet, a mobile communication network, a dedicated line, or the like is used. The terminal device 32 can be selected from a tablet terminal, a smartphone, and the like in addition to a personal computer, and may be a thin client.

In addition, the abnormality monitoring device 10 transfers the operation state of the photovoltaic power generation facility 20 grasped by the abnormality monitoring device 10 to the terminal device 32 used by the consumer who receives the power generated by the photovoltaic power generation facility 20. It is possible. In this case, the terminal device 32 can also be used as a tool for providing information to consumers.

The sampling device 101 may determine the sampling period 101 and the sampling period 102 instead of the data acquisition interface 11. That is, the data acquisition interface 11 may be configured to receive an integrated value of a plurality of electrical outputs in the sampling period 102 from the measurement device 23 every sampling period 101. The data acquisition interface 11 may output the average value of the plurality of electrical outputs in the sampling period 102 to the monitoring unit 12 instead of the integrated value of the plurality of electrical outputs in the sampling period 102.

In the example of FIG. 1, the abnormality monitoring device 10 includes a built-in clock (timer) 13, but the present embodiment is not limited to this. For example, the measuring device 23 includes a timer, acquires the electrical output data (first data) of the solar cell 21 for each sampling period 101, and transmits the data to the abnormality monitoring device 10 (data acquisition) through the communication unit 231. It may be configured to supply to the interface 11). Similarly, when the device 2 is the pyranometer 25, the measuring device 23 includes a timer, acquires the electric output data (second data) of the pyranometer 25 for each sampling period 101, and passes through the communication unit 231. The data may be supplied to the abnormality monitoring apparatus 10 (data acquisition interface 11). In the configuration in which the timer is provided in either the abnormality monitoring device 10 or the photovoltaic power generation facility 20, the data acquisition interface 11 acquires data (first data or second data) together with corresponding time information, It is desirable that corresponding time information is assigned to the data. The time information is information on the time at which the corresponding data is acquired, and is date information in this embodiment.

The monitoring unit 12 is configured to extract an electrical output delivered from the data acquisition interface 11, for example, a power value corresponding to a basic pattern from an output pattern of a plurality of power values, and compare the extracted power value with a reference value. ing. The reference value will be described later. For example, the monitoring unit 12 includes one or more processors and a storage unit 123. In order to extract the power value corresponding to the basic pattern from the power value acquired by the data acquisition interface 11, in this embodiment, an extraction time 110 longer than the sampling period 101 is defined as shown in FIG. Obtain the average rate of change of the power value. The extraction time 110 is determined such that a short-time fluctuation component in the output pattern is suppressed and the change tendency of the power value can be extracted. Specifically, the extraction time 110 is in the range of about 20 to 40 times the sampling period, and more preferably about 30 times the sampling period.

In the present embodiment, as shown in the example of FIG. 2, the average change rate C (n) at the start point of the extraction time 110 is an average value of a plurality of power values acquired in the sampling period 102 at the start point of the extraction time 110. The difference between the average power value P (n) and the average power value P (n + 30) that is the average value of the plurality of power values acquired in the sampling period 102 at the end of the extraction time 110 is the extraction time 110 (30 minutes). It is the value divided. Thus, the average rate of change C (n), C (n + 1),..., C (n + 30) is obtained for each sampling period 101. In the example of FIG. 2, the extraction time 110 is 30 times the sampling period 101, the power value of the nth sampling period is P (n), and the power value after 30 minutes is P (n + 30). The average rate of change C (n) corresponding to the starting point is calculated as {P (n + 30) −P (n)} / 30. Since the start time of the nth sampling period 101 is 11:00, the average rate of change C (n) corresponding to 11:00 becomes {P (n + 30) −P (n)} / 30. Become. Similarly, the average change rate C (n + 1) at 11:01 is calculated as {P (n + 31) −P (n + 1)} / 30.

In short, in this embodiment, the monitoring part 12 memorize | stores the data of the electrical output of the solar cell 21 (each string 211) in the memory | storage part 123 (1st area | region 1231) with corresponding time information for every sampling period 101. FIG. Configured as follows. In the case of the configuration A, an integrated value or an average value of a plurality of power values is stored in the storage unit 123 together with corresponding time information for each sampling period 101. In the example of FIG. 2A, the power value (for example, P (n)) at the sampling time point (for example, 11:00) for each sampling period 101 is the sampling period in the sampling period 101 whose end point is the sampling time point (11:00). The integrated value or average value of the plurality of power values obtained at 102 is stored together with the corresponding time information (including 11:00). In the case of configuration B, the power value is stored in the storage unit 123 together with the corresponding time information for each sampling period 101. In the example of FIG. 2A, a power value (for example, P (n)) at a sampling time point (for example, 11:00) for each sampling period 101 is stored together with corresponding time information (including 11:00).

In addition, the monitoring unit 12 outputs the electrical output of the solar cell 21 corresponding to the sampling cycle 101 at the start point of the extraction time 110 for each sampling cycle 101 based on the electrical output data of the solar cell 21 stored in the storage unit 123. The average change of the start point of the extraction time 110 from the value P (n) of the extraction time 110, the value P (n + 30) of the electrical output of the solar cell 21 corresponding to the sampling period 101 at the end point of the extraction time 110, and the value of the extraction time 110 It is configured to determine the rate C (n).

Similarly, when the apparatus 2 is the pyranometer 25, the monitoring unit 12 stores the electric output data of the pyranometer 25 in the storage unit 123 (first region 1231) together with the corresponding time information for each sampling period 101. Configured to do. Here, in the case of the configuration A, an integrated value or an average value of a plurality of values relating to the solar radiation intensity is stored in the storage unit 123 together with corresponding time information. In the case of Configuration B, a value related to solar radiation intensity is stored in the storage unit 123 together with corresponding time information for each sampling period 101.

In addition, the monitoring unit 12 outputs the electrical output of the pyrometer 25 corresponding to the sampling period 101 at the start point of the extraction time 110 for each sampling period 101 based on the electrical output data of the pyranometer 25 stored in the storage unit 123. The average change of the starting point of the extraction time 110 from the value P (n) of the extraction time 110, the value P (n + 30) of the electrical output of the pyranometer 25 corresponding to the sampling period 101 at the end point of the extraction time 110, and the value of the extraction time 110 It is configured to determine the rate C (n).

The above formula for calculating the average rate of change is an example, and other formulas may be used. For example, the average rate of change at a specific time may be defined by the following equation from the values before and after 15 minutes. That is, {P (n + 15) −P (n−15)} / 31 may be obtained.

The average rate of change obtained by the above calculation represents the slope of the power value at the corresponding time. Here, the average change rate obtained with the extraction time set to an appropriate length of time is substantially equal to the average change rate of the basic pattern (solid line in FIG. 4) from which the superposed pattern (dotted line in FIG. 4) is removed. I know that. Moreover, since the average rate of change represents the slope of the power value, the change in the average rate of change with time represents the shape of the output pattern, but does not depend on the magnitude of the power value. Hereinafter, a figure in which the average change rates are arranged along the time axis is referred to as a “change rate pattern”.

Here, we briefly consider the extraction time. When the extraction time coincides with the sampling period 101, that is, when the extraction time is 1 minute, the component corresponding to the superimposed pattern cannot be removed from the change rate pattern as shown in FIG. 3A. Further, when the extraction time is 7 minutes, a part of the component corresponding to the superposition pattern is removed from the change rate pattern as shown in FIG. Many are left behind. On the other hand, when the extraction time is 30 minutes, as shown in FIG. 3C, the component corresponding to the superimposed pattern is almost removed from the change rate pattern, and the component corresponding to the basic pattern is extracted. Therefore, the basic pattern can be extracted using the change rate pattern by setting the extraction time relatively long.

Here, when the maximum value for each time of day is extracted from the power values for a plurality of days (for example, 15 days) without using the average rate of change, the power values for each time ( In FIG. 4, the change in the solar radiation intensity is used as a value equivalent to the power value. This is considered to be because the solar radiation intensity irradiated to the solar cell 21 greatly fluctuates even on a sunny day due to the state of clouds or the surrounding environment of the solar cell. That is, as shown by a broken line in FIG. 4, the figure in which the maximum values for each time extracted from the output patterns of a plurality of days are arranged in a shape in which the superposition pattern is superimposed on the basic pattern. On the other hand, when the technique of the present embodiment described below is adopted, it is possible to remove the component corresponding to the superimposed pattern and extract the component corresponding to the basic pattern as shown by the solid line in FIG. .

The monitoring unit 12 is configured to switch between an operation of generating a reference value pattern and an operation of monitoring the presence or absence of abnormality of the solar cell 21 based on the generated reference value pattern. Further, the operation for generating the reference value pattern includes an operation for generating an ideal sunny day change rate pattern and an operation for generating the reference value pattern from the electrical output data of the solar cell 21. Here, the operation for generating the change rate pattern for an ideal sunny day is referred to as “pre-operation (first operation)”, and the operation for generating the reference value pattern from the electrical output of the solar cell 21 is referred to as “generation operation (first operation). 2 operations) ”.

The monitoring unit 12 includes a determination unit 120, a calculation unit 121, a filter unit 122, and a storage unit 123. The memory | storage part 123 is 1st area | region 1231 which memorize | stores the data of an output pattern (The data of the electrical output of the solar cell 21 from the data acquisition interface 11, for example, electric power value), and the data of the change rate pattern obtained by pre-operation Are stored in the second area 1232 and the third area 1233 stores the reference value pattern data obtained by the generation operation.

The determination unit 120 compares the reference value pattern data stored in the storage unit 123 with the power value data acquired by the data acquisition interface 11 and makes a determination as described above. Judge whether there is. That is, the determination unit 120 determines whether or not there is an abnormality in the solar cell 21 by comparing the power value obtained from the data acquisition interface 11 with the reference value obtained from the data of the reference value pattern.

The calculation unit 121 obtains an average rate of change based on the output pattern data stored in the first area 1231 in both the pre-operation and the generation operation. That is, in the first region 1231, the power value data from the solar cell 21 is stored in one-to-one correspondence with the time of the day, and the calculation unit 121 stores the data of two power values. Use to calculate the average rate of change.

In short, in the example of FIG. 2, the calculation unit 121 calculates 2 at both ends of the extraction time 110 for each extraction time 110 from the electrical output data of the solar cell 21 stored in the storage unit 123 (first region 1231). A value (for example, a power value or a power amount) of the electrical outputs is obtained, and an average rate of change is calculated from the values of the two electrical outputs and the extraction time 110. Here, the extraction time 110 is shifted by the sampling period 101 every sampling period 101.

Similarly, when the device 2 is the pyranometer 25, the calculation unit 121 extracts the extraction time for each extraction time 110 from the electric output data of the pyranometer 25 stored in the storage unit 123 (first region 1231). Two electrical output values (for example, solar intensity value or solar radiation amount) at both ends of 110 are obtained, and the average rate of change is calculated from the two electrical output values and the extraction time 110. Here, the extraction time 110 is shifted by the sampling period 101 every sampling period 101.

In the pre-operation, the output pattern on the day when the user determines that the weather is clear is regarded as an ideal sunny day output pattern. The calculation unit 121 obtains the average rate of change at each time of the day based on the data of this output pattern (that is, the power value at each time), and uses the obtained average rate of change at each time as the standard rate of change at each time It is stored in the second area 1232 of the storage unit 123. That is, in the pre-operation, a change rate pattern in which a standard change rate is associated with each time of the day is generated.

In one example, the communication interface 14 is an input / output interface having an input / output function, and the monitoring unit 12 receives a sunny day input instruction from the user via the input / output interface 14. Configured. In the pre-operation, the calculation unit 121 extracts an extraction time on a day (for example, a predetermined time zone) corresponding to the input instruction based on the electrical output data of the solar cell 21 stored in the storage unit 123 (first region 1231). For each 110, an average rate of change is calculated from two electrical output values (for example, power value or power amount) at both ends of the extraction time 110, and each of the obtained average rate of change is used as a standard rate of change. The corresponding time information is stored in the second area 1232 of the storage unit 123. The extraction time 110 is shifted by the sampling period 101 every sampling period 101.

Similarly, when the device 2 is the pyranometer 25, the calculation unit 121 performs an input instruction based on the electric output data of the pyranometer 25 stored in the storage unit 123 (first region 1231) in the pre-operation. For each extraction time 110 on a day corresponding to (for example, a predetermined time period), an average rate of change is calculated from two electrical output values (for example, a solar radiation intensity value or a solar radiation amount) at both ends of the extraction time 110. Each of the plurality of average change rates is configured to be stored in the second area 1232 of the storage unit 123 for each corresponding time information as a standard change rate. The extraction time 110 is shifted by the sampling period 101 every sampling period 101.

In the generation operation, the calculation unit 121 obtains the average rate of change at each time from the data of the output pattern of the appropriate day (power value from the data acquisition interface 11). The filter unit 122 compares the obtained average change rate for each time with the standard change rate at the same time stored in the storage unit 123. Specifically, as shown in FIG. 5, the filter unit 122 sets a predetermined allowable range AR to the standard change rate RC at each time stored in the storage unit 123, and the same time obtained by the calculation unit 121. If the average rate of change is within the allowable range AR, the power value at the date and time when the average rate of change was obtained is regarded as the reference value. The power value data that the filter unit 122 regards as the reference value is stored in the third area 1233 of the storage unit 123. The allowable range AR is determined as a ratio with respect to the standard change rate RC or a constant value. When the allowable range AR is set as a ratio with respect to the standard change rate RC, for example, it may be selected from about ± 0.1RC to ± 0.3RC.

In an example of the generation operation, the calculation unit 121 calculates an average rate of change from two electrical output values (for example, power values) at both ends of the extraction time 110 for each extraction time 110 in one day (for example, a predetermined time period). Configured to calculate. Here, the extraction time 110 is shifted by the sampling period 101 every sampling period 101. As an example, the above-mentioned one day (for example, a predetermined time period) is set every time the electrical output data of the solar cell 21 (or the solar radiation meter 25) is stored in the storage unit 123 (first region 1231). As another example, the one day is set according to an input instruction for one day or a plurality of days obtained from the terminal device 32 via the input / output interface 14. Each time the average rate of change in the above-described one day (for example, a predetermined time period) is obtained, the filter unit 122 stores the average rate of change in the corresponding time information standard stored in the storage unit 123 (second region 1232). If within the allowable range AR including the change rate RC in between (for example, at the center), the electric output value of the average change rate (the electric output value corresponding to at least the start point of the extraction time 110) is stored as a reference value. It is configured to store in the third area 1233 of the unit 123. Note that the value of the electrical output corresponding to the end point of the extraction time 110 may be stored in the same manner.

As an example, it is assumed that the standard change rate of 11:00 stored in the second area 1232 of the storage unit 123 is 0.001 and the allowable range set in the filter unit 122 is ± 0.0002. . If the average change rate of 11:00 obtained by the calculation unit 121 is 0.0011, the filter unit 122 regards the power value at the date and time when the average change rate is obtained as a reference value, and sets the corresponding date and time. The power value data is stored in the third area 1233 of the storage unit 123 in association with the time. On the other hand, if the average change rate of 11:00 obtained by the calculation unit 121 is 0.003, the filter unit 122 discards the power value at the date and time when the average change rate was obtained.

By the way, if the period of clear weather during the day is a relatively long day, a relatively large amount of power value data is stored in the third area 1233 of the storage unit 123. However, on a day when the day is fine during the day, a day when it is cloudy during the day, and a day when it is rainy during the day, the power value data stored in the third area 1233 of the storage unit 123 is Become a minority. When trying to determine whether or not there is an abnormality in the solar cell 21 based on the power value data constituting the reference value pattern, it can be said that, generally, the greater the amount of data, the higher the certainty of the determination.

However, even in the case of the power value data for one day, in the time zone (for example, from 10 o'clock to 13 o'clock) including the time in the south and middle times, the data in the period when it is fine occupies a ratio of the predetermined value or more. If it is, the power value data for one day can be used as the reference value pattern. The ratio above the predetermined value is, for example, 80% or more. This numerical value is not intended to be limiting but is shown as an example.

FIG. 6 shows an example of extracting reference value pattern data (reference values to be stored in the third area 1233) in the above-described procedure. FIG. 6A shows an ideal output pattern. When the data of the change rate pattern is extracted from the data of the ideal output pattern by calculation of the calculation unit 121, the change rate pattern is as shown in FIG. 6B. On the other hand, FIG. 6C shows an output pattern of actual measurement values. When data of a change rate pattern is extracted from the actual measurement values by calculation of the calculation unit 121, the change rate pattern is as shown in FIG. 6D. The filter unit 122 extracts the reference value pattern data as shown in FIG. 6E by collating the change rate pattern data shown in FIG. 6D with the change rate pattern data shown in FIG. 6B. That is, the filter unit 122 calculates the average rate of change between both data from the rate of change pattern data obtained from the ideal output pattern shown in FIG. 6B and the rate of change pattern data obtained from the actually measured value shown in FIG. A matching time within the allowable range AR is obtained, and the obtained time is compared with the data of the output pattern in FIG. 6C to extract the power value at that time. In FIG. 6A, FIG. 6C, and FIG. 6E, the vertical axis uses the solar radiation intensity, but is equivalent to the power value output by the solar cell 21.

In order to increase the amount of data constituting the reference value pattern, it is possible to use the power value data for a plurality of days extracted by the filter unit 122. If the power value is for multiple days that can be regarded as the same season, the solar altitude corresponding to the time is almost the same, so the solar radiation intensity in fine weather is also almost the same. By utilizing this, in the present embodiment, the power value data extracted by the filter unit 122 for the segment period set to include a plurality of days within the period in which the change in solar altitude at the same time is within a predetermined range is used. The data is stored in the third area 1233 of the storage unit 123. In this case, the third area 1233 of the storage unit 123 allows storing data of a plurality of power values for the same time.

* Here, the segment period is selected in the range of 2 weeks to 1 month. For example, the period that can be regarded as the same season can be a plurality of days (15 days) included in one of the twenty-four seasons. In addition, as a period that can be regarded as the same season, a plurality of days in the first half of each month, a plurality of days in the second half of each month, a plurality of days in one month, and the like can be adopted. In short, a period in which the solar altitudes are almost equal is selected as a period that can be regarded as the same season.

Now, it is assumed that three types of reference value patterns as shown in FIGS. 7A, 7B, and 7C are extracted from the power values for each day based on the power values for three days. In this case, it is possible to generate a reference value pattern as shown in FIG. 7D by superimposing these reference value patterns. The reference value patterns shown in FIGS. 7A, 7B, and 7C are disordered and cannot be used as a reference value pattern for one day, but a plurality of reference value patterns are superimposed as shown in FIG. 7D. Thus, a substantially complete reference value pattern is included.

Incidentally, the reference value pattern shown in FIG. 7D includes a plurality of values at the same time, and cannot be used as a reference value pattern as it is. Therefore, when there are data of a plurality of power values at the same time in the third area 1233 of the storage unit 123, the monitoring unit 12 selects one of the data of the plurality of power values and sets the reference value The selector 124 is configured to determine the following.

The selection unit 124 is configured to select one of the power value data stored in the storage unit 123 as a reference value, and store the selected reference value in the third area 1233 of the storage unit 123. As the reference value, one piece of appropriate power value data may be selected from a plurality of power value data at the same time according to a certain rule. The rule for selecting the reference value is determined so as to adopt the maximum value among the data of the plurality of power values.

Here, in the above-described operation example, the power value data at the same time obtained from a plurality of days is stored in the storage unit 123, and then the selection unit 124 selects the power value data as the reference value. On the other hand, if the power value data is to be stored in the third area 1233 of the storage unit 123, the power value data at the same time as the power value data is already stored in the third area 1233. The selection unit 124 may be configured to store only one of them in the storage unit 123. In this case, the selection unit 124 compares the power value data stored in the storage unit 123 with the power value data to be stored in the storage unit 123, and stores the larger power value data. The rule of storing in the third area 1233 of the unit 123 is used.

In short, in the present embodiment, when the plurality of reference values exist at at least one time of one day (for example, a predetermined time period) to be stored in the third area 1233 of the storage unit 123, Only the maximum value among the plurality of reference values is configured to be stored in the third region 1233.

By the way, since the filter unit 122 extracts a power value serving as a reference value based on the average change rate of the power value, there is a possibility that the filter unit 122 may be misidentified as a reference value candidate and extracted depending on a daily output pattern. . That is, if the average change rate of the power value is within an allowable range set with respect to the standard change rate, the filter unit 122 sets the corresponding power value as a reference value candidate regardless of the absolute value of the power value. Since extraction is performed, a power value that does not correspond to a clear day may be extracted as a reference value candidate. For example, in the case of FIG. 7A, the power value not corresponding to a clear day is a portion where the power value is discontinuous, such as the right portion.

Such a power value that does not correspond to a clear day will be referred to as an “error component”. When the reference value pattern formed by the reference values stored in the third area 1233 of the storage unit 123 includes an error component, the reference value pattern includes a power value corresponding to a clear day and a power value that is not a clear day. It will be out. In order to reduce an error component from such a reference value pattern, the filter unit 122 can perform an iterative process for the reference value pattern by performing the same processing as the power value data acquired from the data acquisition interface 11. It is configured. The iterative process is performed at least once, and a plurality of iterative processes can be performed as necessary. The number of iterations may normally be about once or twice.

Also, it is desirable that the filter unit 122 narrows the allowable range set for the standard change rate during the iterative processing, compared to the allowable range used when the reference value candidates are first extracted. For example, as shown in FIG. 8A, the allowable range AR1 used when extracting the reference value candidate based on the power value data acquired by the data acquisition interface 11 is set to ± α. Further, as shown in FIG. 8B, the allowable range AR2 used when iterative processing is performed on the reference value data stored in the third area 1233 of the storage unit 123 is set to ± β (α> β> 0). In this way, not only the iterative process is performed, but also the error component is further removed by narrowing the allowable range during the iterative process, and as a result, a reference value pattern with a high ratio of reference values corresponding to sunny days Can be generated.

In the configuration example described above, it is assumed that a reference value (reference value pattern) for one day is generated and the reference value for one day is used throughout the year. Although the power value acquired from the solar cell 21 by the data acquisition interface 11 varies relatively greatly depending on the season, as described above, if it is a predetermined time zone (for example, from 10:00 to 13:00) during the day, Even if the absolute value changes, the average rate of change is almost the same. Therefore, the configuration example described above employs a configuration that uses a reference value for one day throughout the year. However, since the absolute value changes, one year may be divided into a plurality of periods, and a reference value may be set for each divided period. Even in this case, it is possible to determine whether or not the solar cell 21 is abnormal throughout the year only by storing a small number of reference values (reference value patterns) in the third region 1233 of the storage unit 123.

The abnormality monitoring apparatus 10 described above includes, as main hardware elements, a first device including one or more processors that execute a program and an interface second device for connecting an external apparatus. The first device is selected from a microprocessor to which a memory is connected separately, a microcomputer having a memory integrally, and the like.

The program may be provided in a state written in a ROM (Read Only Memory) in advance, but is provided on a computer-readable recording medium so that it can be stored in a rewritable nonvolatile memory. Is desirable. Further, the program may be provided through an electric communication line such as the Internet instead of the recording medium.

The abnormality monitoring apparatus 10 described above includes a data acquisition interface 11 and a monitoring unit 12. The data acquisition interface 11 is supplied from the device 2 that outputs an electrical output according to the solar radiation intensity for each time of a day (preferably in a predetermined time zone including a South-Central time that is a part of the day). An output value (integrated value or average value in configuration A) is acquired. The monitoring unit 12 monitors the presence or absence of an abnormality in the device 2 by comparing the value of the electrical output for each time of day from the data acquisition interface 11 with the corresponding reference value among the reference values for each time of the day. Configured to do. The device 2 includes at least one of the solar cell 21 and the pyranometer 25. Furthermore, the monitoring unit 12 includes a calculation unit 121, a filter unit 122, and a storage unit 123. Based on the value of the electrical output from the data acquisition interface 11, the calculation unit 121 corresponds to the time at both ends of the extraction time 110 for each predetermined extraction time 110 (for the above-mentioned one day, preferably for the above-mentioned predetermined time zone). The average rate of change is calculated from the two electrical output values and the extraction time 110. The filter unit 122 has a value of an electrical output having an average rate of change within a predetermined allowable range AR out of the average rate of change for each extraction time 110 from the calculation unit 121 (at least the electrical output corresponding to the start point of the extraction time 110). The tolerance range AR is a tolerance range of a corresponding time among a plurality of tolerance ranges for each time of a day (preferably in the predetermined time zone), and a plurality of tolerance ranges are extracted. Each of the ranges is a range including the standard change rate RC in the middle (preferably the center), and the plurality of standard change rates of the plurality of allowable ranges correspond to a clear day (obtained in advance from the calculation unit 121). It is the average rate of change for a day (preferably the predetermined time period). The storage unit 123 is configured to store the value of the electrical output extracted by the filter unit 122 as a reference value together with corresponding time information.

According to this configuration, it is possible to accurately generate a reference value corresponding to a clear day based on the actual measurement value of the electrical output of the device 2. The reference value set in this way can be used over a long period of time.

In this abnormality monitoring apparatus 10, it is desirable that the data acquisition interface 11 is configured to acquire the value of the electric output every time of the day by acquiring the value of the electric output at a predetermined sampling period 101. . In this case, the extraction time 110 may be an integral multiple of the sampling period 101. Here, the integer multiple is two times or more, and the time that is an integral multiple of the sampling period 101 is shorter than, for example, the time from the sunrise time to the South-Central time or the time from the South-Central time to the sunset time. For example, the extraction time 110 has a length of time in which the fluctuation component of the value of the electrical output in the sampling period 101 is suppressed and the average change rate that is a tendency of change in the value of the electrical output can be extracted. Determined. Desirably, the time that is an integral multiple of the sampling period 101 is shorter than the time between the intermediate time point and the start or end time point of the time zone that defines the reference value (the time zone that includes the South-Central time). Determined in time. In one specific example, the extraction time 110 is in the range of about 20 to 40 times the sampling period 101, more preferably 30 times the sampling period 101. In one embodiment, the sampling period is selected from the range of about 30 seconds to 10 minutes, preferably 1 minute. The storage unit 123 is configured to allocate and store each of the plurality of reference values from the filter unit 122 to the corresponding time information set in the sampling period 101.

According to this configuration, when the extraction time 110 is set appropriately, the average rate of change is required to remove the influence of the fluctuation component of the electrical output in a short time. That is, the reference value data obtained by removing unnecessary fluctuation components from the output pattern described above can be stored in the storage unit 123.

The storage unit 123 converts each of the plurality of electrical output values extracted by the filter unit 122 from the electrical output values for a plurality of days obtained from the data acquisition interface 11 via the calculation unit 121 into corresponding time information for one day. It is desirable to assign and memorize.

According to this configuration, even when the number of electrical output values corresponding to a clear day is not sufficiently obtained with the electrical output for one day, by superimposing the electrical output values for a plurality of days, The number of corresponding electrical output values can be increased.

Here, when the filter unit 122 extracts a plurality of electrical output values for the same time on different days, the monitoring unit 12 corresponds to the maximum value among the plurality of electrical output values extracted for the same time. It is desirable to include a selection unit 124 that is stored in the storage unit 123 as a reference value for the time to be used.

This configuration makes it possible to extract an appropriate reference value based on the electric output values for a plurality of days.

The filter unit 122 compares the already extracted average change rate with the corresponding standard change rate again, and repeats the iterative process of extracting the average change rate within the corresponding allowable range from the already extracted average change rate once. It is desirable to be configured to repeat the above.

According to this configuration, even when an error component is included in the value of the electrical output extracted by the filter unit 122, the ratio of the error component is reduced by performing iterative processing, which corresponds to a clear day. It becomes possible to relatively increase the ratio of the value of the electric output.

It is desirable that the filter unit 122 is configured to narrow the allowable range every time iterative processing is performed once.

According to this configuration, it is possible to further reduce the error component by tightening the standard for extracting the value of the electric output every time the iterative process is repeated.

The standard rate of change is preferably set for each segment period set to include multiple days. For example, the segment period is selected in the range of about 2 weeks to 1 month.

According to this configuration, it becomes possible to reflect the difference in solar altitude in the reference value, and by using an appropriate reference value, the determination condition as to whether there is an abnormality in the device 2 is set more strictly, The determination accuracy can be increased.

The photovoltaic power generation facility 20 in the present embodiment includes a solar cell 21, a pyranometer 25, and the abnormality monitoring device 10 described above. The solar radiation meter 25 is configured to measure the solar radiation intensity to the solar cell 21. For example, the pyranometer 25 is disposed adjacent to the solar cell 21.

This configuration makes it possible to monitor whether or not an abnormality has occurred in at least one of the solar cell 21 and the pyranometer 25 in the solar power generation facility 20.

The program of this embodiment is for causing a computer to function as the abnormality monitoring apparatus 10.

In the configuration example described above, a reference value for determining whether or not an abnormality has occurred in the solar cell 21 is generated. However, a reference value for determining whether or not an abnormality has occurred in the solar radiation meter 25 is used. It is possible to employ the techniques described above to generate. That is, with the above-described technique, the solar cell 21 can be read as the pyranometer 25. Further, the abnormality monitoring device 10 may be configured to monitor whether or not an abnormality has occurred in both the solar cell 21 and the pyranometer 25.

Further, in the configuration example described above, the abnormality of the solar cell 21 is monitored in units of the strings 211, but the abnormality can be monitored in units of the solar cell array.

Although the foregoing best mode and / or other examples are considered, various modifications may be made and the subject matter disclosed herein may be implemented in various forms and examples. And they may be applied to a number of applications, some of which are best described herein. The following claims claim any and all modifications and variations that fall within the true scope of this disclosure.

For example, although the photovoltaic power generation facility 20 shown in FIG. 1 includes the power conversion device 24, when direct current is fed by the power of the solar battery 21, or when the storage battery is charged by the current output from the solar battery 21, etc. Then, the power converter 24 can be omitted.

DESCRIPTION OF SYMBOLS 10 Abnormality monitoring apparatus 11 Data acquisition interface 12 Monitoring part 20 Solar power generation facility 21 Solar cell 25 Solar radiation meter 121 Calculation part 122 Filter part 123 Storage part

Claims (8)

1. A data acquisition interface for acquiring a value of electrical output for each time of day from a device that outputs electrical output according to solar radiation intensity;
   A monitoring unit that monitors the presence or absence of abnormality of the device by comparing the value of the electrical output for each time of day from the data acquisition interface with the corresponding reference value among the reference values for each time of the day Prepared,
   The apparatus includes at least one of a solar cell and a pyranometer,
   The monitoring unit
   Based on the value of the electrical output from the data acquisition interface, a calculation unit that calculates an average rate of change from the value of the electrical output corresponding to the time at both ends of the extraction time and the extraction time for each predetermined extraction time; ,
   The average change rate for each extraction time from the calculation unit is configured to extract an electrical output value of an average change rate within a predetermined allowable range, wherein the allowable range is one day. Among a plurality of permissible ranges for each time, each of the plurality of permissible ranges is a range including a standard change rate, and a plurality of standard change rates of the plurality of permissible ranges is A filter unit that is an average rate of change for one day corresponding to a sunny day;
   An abnormality monitoring system comprising: a storage unit that stores the value of the electrical output extracted by the filter unit as the reference value together with corresponding time information.
2. The data acquisition interface acquires the value of the electrical output at a predetermined sampling period;
   The extraction time is an integral multiple of the sampling period, where the integral multiple is two or more times,
   The abnormality monitoring system according to claim 1, wherein the storage unit assigns and stores each of a plurality of reference values from the filter unit to corresponding time information set in the sampling period.
3. The storage unit converts each of the plurality of electrical output values extracted by the filter unit from the electrical output values for a plurality of days obtained from the data acquisition interface via the calculation unit into corresponding time information for one day. The abnormality monitoring system according to claim 2, wherein the abnormality monitoring system is assigned and stored.
4. The monitoring unit corresponds to a maximum value among the plurality of electrical output values extracted for the same time when the filter unit extracts a plurality of electrical output values for the same time on different days. The abnormality monitoring system according to claim 3, further comprising a selection unit that is stored in the storage unit as a time reference value.
5. The filter unit compares the already extracted average rate of change with a corresponding standard rate of change again, and extracts an average rate of change that is within an allowable range of the corresponding time among the already extracted average rate of change. The abnormality monitoring system according to any one of claims 1 to 4, wherein the process is configured to be repeated one or more times.
6. The abnormality monitoring system according to claim 5, wherein the filter unit is configured to narrow the allowable range each time the iterative process is performed once.
7. The abnormality monitoring system according to any one of claims 1 to 6, wherein the standard change rate is set for each segment period set to include a plurality of days.
8. A program for causing a computer to function as the abnormality monitoring system according to any one of claims 1 to 7.

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