Operating state estimation device, control method for operating state estimation device, and program

Abstract

To estimate the utilization state of a photovoltaic power generation facility without using a solar radiation amount sensor.SOLUTION: A utilization state estimation device estimates a utilization state of a photovoltaic power generation facility. The utilization state estimation device includes: a calculation formula storage section for storing a calculation formula intended to calculate an estimation value of a power generation amount of a photovoltaic power generation facility from meteorological data of prescribed kinds containing a solar radiation amount; a meteorological data acquisition section for acquiring meteorological data; a first index value calculation section for calculating a first index value expressing a level of deviation between an estimation value and an actual value, on the basis of an estimation value of a power generation amount of the photovoltaic power generation facility in a first period that is calculated using the meteorological data and the calculation formula, and an actual value of the power generation amount of the photovoltaic power generation facility in the first period, in each first period; a determination value calculation section for calculating an average value and a standard deviation of the first index value in a prescribed period of the past, to calculate a determination value on the basis of the average value and a standard deviation; and a utilization state estimation section for estimating a utilization state of the photovoltaic power generation facility on the basis of a comparison result of the first index value and the determination value.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an operating state estimation device, a control method for the operating state estimation device, and a program.

Background Art

[0002] When a photovoltaic power generation facility fails, the power generation amount decreases. However, since the power generation amount fluctuates greatly under the influence of changes in solar radiation, just because the power generation amount has decreased, it does not necessarily mean that the photovoltaic power generation facility has failed. Therefore, it is not easy to estimate whether the photovoltaic power generation facility is operating properly.

[0003] Therefore, in the case of a photovoltaic power generation facility installed in a large-scale photovoltaic power plant such as a megasolar power plant, the operating state is estimated by using a solar radiation sensor or by combining a solar radiation sensor with other sensors such as an ammeter (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the case of a relatively inexpensive and low-output photovoltaic power generation facility installed in a home or the like, there is also a need to suppress costs, and a solar radiation sensor such as that installed in a large-scale power generation plant is often not provided.

[0006] Therefore, in a home or the like, even if the photovoltaic power generation facility has failed and the power generation amount has decreased, it is often not noticed, which also has a great impact on the monthly electricity bill of that home.

[0007] Therefore, there is a need for a technology that enables the estimation of the operating state of a solar power generation facility without using a solar radiation sensor.

[0008] The present invention has been made in view of the above problems, and an object thereof is to provide an operating state estimation device, a control method for the operating state estimation device, and a program that can estimate the operating state of a solar power generation facility without using a solar radiation sensor.

Means for Solving the Problems

[0009] The operating state estimation device for solving the above problems is an operating state estimation device for estimating the operating state of a solar power generation facility, and includes a calculation formula storage unit that stores a calculation formula for calculating an estimated value of the power generation amount of the solar power generation facility from predetermined types of meteorological data including solar radiation amount, a meteorological data acquisition unit that acquires the meteorological data from a meteorological data providing device connected communicably, and a first index value calculation unit that calculates a first index value representing the degree of deviation between the estimated value and the actual value based on the estimated value of the power generation amount of the solar power generation facility in the first period calculated using the meteorological data and the calculation formula and the actual value of the power generation amount of the solar power generation facility in the first period, for each first period in which the operating state of the solar power generation facility is periodically estimated, a determination value calculation unit that calculates the average value and standard deviation of the first index value in a past predetermined period and calculates a determination value based on the average value and the standard deviation, and an operating state estimation unit that estimates the operating state of the solar power generation facility based on the result of comparison between the first index value and the determination value. On a two-dimensional coordinate plane in which the estimated power generation amount is made to correspond to the first coordinate axis and the actual power generation amount is made to correspond to the second coordinate axis, display a region representing the operating state of the photovoltaic power generation facility and a point determined from the estimated power generation amount and the actual power generation amount in the first period. and

[0010] In addition, the problems disclosed in the present application and the solutions thereto are clarified by the description in the section of the mode for carrying out the invention, the description in the drawings, and the like.

Effects of the Invention

[0011] It becomes possible to estimate the operating state of a solar power generation facility without using a solar radiation sensor.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Mode for Carrying Out the Invention

[0013] From the description in this specification and the accompanying drawings, at least the following matters become clear. Hereinafter, the present invention will be described with reference to the accompanying drawings according to one embodiment thereof.

[0014] ==Overall Configuration== The overall configuration of an operating state estimation system 1000 according to an embodiment of the present invention is shown in FIG. 1.

[0015] The operating state estimation system 1000 is configured such that the operating state estimation device 100 and the solar power generation facility 300 are communicably connected via a network 500 such as the Internet, a LAN (Local Area Network), or a telephone network. The operating state estimation system 1000 is also communicably connected to a weather data providing device 200.

[0016] In this embodiment, for the sake of simplicity of explanation, it is described that the solar power generation facility 300 is communicably connected to the operating state estimation device 100. More specifically, a smart meter (not shown) is provided at the installation location of the solar power generation facility 300, and the solar power generation facility 300 is communicably connected to the operating state estimation device 100 through this smart meter.

[0017] The operating state estimation device 100 is an information processing device such as a computer that acquires predetermined types of weather data including solar radiation amount and actual power generation values from the weather data providing device 200 and the solar power generation facility 300 (smart meter), and estimates the operating state of the solar power generation facility 300.

[0018] Specifically, the operating state estimation device 100 estimates the operating state of the solar power generation facility 300 by comparing the actual power generation value of the solar power generation facility 300 with the estimated power generation value of the solar power generation facility 300 separately calculated using weather data. In such a manner, it becomes possible to estimate the operating state of the solar power generation facility without using a solar radiation sensor.

[0019] The weather data providing device 200 is a computer that provides various weather data including solar radiation amount. The weather data includes weather forecast data created using the LFM (Local-Forcast Model) provided by the Japan Meteorological Agency and weather forecast data created using the MSM (Meso-Scale Model) (hereinafter also referred to as MSM data). For example, the weather data providing device 200 provides the MSM as weather data.

[0020] The MSM data is obtained by numerically calculating predicted values of specified types of meteorological conditions in regions divided into a grid pattern with a side length of 5 km. The Japan Meteorological Agency distributes MSM data every three hours (i.e., eight times a day) at one-hour intervals up to 39 hours ahead. Additionally, twice a day, it provides MSM data at one-hour intervals up to 51 hours ahead. This MSM data includes predicted values of various meteorological data such as solar radiation, atmospheric pressure, temperature, relative humidity, precipitation, and cloud cover.

[0021] The solar power generation facility 300 is a power generation facility that generates electricity using solar energy (natural energy). The solar power generation facility 300 according to this embodiment targets those without a solar radiation sensor installed, and for example, facilities with a relatively small power generation capacity installed in general households and the like are applicable.

[0022] The actual value of the power generation amount of the solar power generation facility 300 is measured by a smart meter (not shown) and transmitted to the operation state estimation device 100 at predetermined time intervals (for example, every hour).

[0023] ==Operation State Estimation Device== Next, the operation state estimation device 100 will be described.

[0024] An example of the hardware configuration of the operation state estimation device 100 is shown in FIG. 2. The operation state estimation device 100 includes a CPU (Central Processing Unit) 110, a memory 120, a communication device 130, a storage device 140, an input device 150, an output device 160, and a recording medium reader 170.

[0025] The CPU 110 controls the entire operation state estimation device 100, reads out from the storage device 140 the operation state estimation device control program 600 and various data composed of codes for performing various operations according to this embodiment, and executes or processes them in the memory 120, thereby realizing various functions as the operation state estimation device 100.

[0026] For example, the CPU 110 executes or processes the operating state estimation device control program 600 and various data, and cooperates with hardware devices such as the memory 120, the communication device 130, and the storage device 140, thereby realizing various functions such as the calculation formula storage unit 101, the weather data acquisition unit 102, the first index value calculation unit 103, the operating state estimation unit 104, and the determination value calculation unit 105, which will be described later.

[0027] The operating state estimation device control program 600 is a general term for programs for realizing the functions of the operating state estimation device 100, and includes, for example, application programs, operating systems (OS), and various libraries that operate on the operating state estimation device 100.

[0028] The memory 120 can be constituted by, for example, a semiconductor memory device.

[0029] The storage device 140 is a device that provides a physical storage area for storing various programs, data, tables, etc., such as hard disk drives, SSDs (Solid State Drives), and flash memories. In the present embodiment, as shown in FIG. 3, the storage device 140 stores various data such as the operating state estimation device control program 600, the weather data table 400, the actual power generation value table 410, the equipment table 420, the coefficient table 430, and the calculation formula 440.

[0030] An example of the weather data table 400 is shown in FIG. 4.

[0031] The operating state estimation device 100 acquires predetermined types of weather data including solar radiation amount from the weather data providing device 200 every predetermined time (every 3 hours in the present embodiment), and stores these weather data in the weather data table 400.

[0032] As shown in FIG. 4, the weather data table 400 has a "prediction time" column, a "prediction target time" column, a "solar radiation amount" column, an "air temperature" column, and a "wind speed" column.

[0033] In the "Prediction Time" column, the date and time when the weather data providing device 200 distributes weather data (MSM data) is described. As described above, the weather data providing device 200 provides MSM data 8 times a day at 3-hour intervals, and those dates and times are described in the "Prediction Time" column.

[0034] In the "Prediction Target Time" column, date and time information indicating the prediction target time, that is, the time for which the weather data is predicted, is described. When the prediction time is 0:00 and 12:00, date and time information up to 51 hours ahead is described, and when the prediction time is 3:00, 6:00, 9:00, 15:00, 18:00, and 21:00, date and time information up to 39 hours ahead is described.

[0035] In the "Solar Radiation Amount" column, predicted values of the solar radiation amount at each prediction target time are described. In the "Air Temperature" column, predicted values of the air temperature at each prediction target time are described. In the "Wind Speed" column, predicted values of the wind speed at each prediction target time are described. Although not shown in FIG. 4, the weather data table 400 may store predicted values of other types of weather data such as atmospheric pressure and cloud cover.

[0036] The operating state estimation device 100 adds MSM data to the weather data table 400 every 3 hours when MSM data is distributed from the weather data providing device 200.

[0037] Note that it is considered that the prediction accuracy of the weather data is higher the closer it is to the distribution time. Therefore, when the operating state estimation device 100 according to the present embodiment calculates an estimated value of the power generation amount of the solar power generation facility 300 using the weather data, among the 39 or 51 pieces of weather data obtained at each distribution time, the 3 pieces of weather data closest to the distribution time, that is, the weather data whose prediction target time is before the next distribution time (the 3 closest pieces of weather data at each distribution time marked with a star in FIG. 4) are used.

[0038] Therefore, instead of storing all 39 or 51 pieces of weather data obtained at each distribution time in the weather data table 400, the operation state estimation device 100 may store only the weather data from each distribution time to the next distribution time as indicated by the star marks in FIG. 4. In such a manner, it becomes possible to reduce the data capacity of the weather data table 400.

[0039] Subsequently, an example of the generated power actual value table 410 is shown in FIG. 5.

[0040] The operation state estimation device 100 acquires the actual value of the generated power from the solar power generation facility 300 every predetermined time (every 1 hour in this embodiment) and records it in the generated power actual value table 410.

[0041] As shown in FIG. 5, the generated power actual value table 410 stores the actual value of the generated power by the solar power generation facility 300 in association with the date and time information. The actual value of the generated power is the sum of the generated power in the most recent predetermined time (1 hour).

[0042] Next, an example of the facility table 420 is shown in FIG. 6.

[0043] The facility table 420 records information regarding the solar power generation facility 300 that is used when calculating the estimated value of the generated power of the solar power generation facility 300 from the weather data. As shown in FIG. 6, for example, the facility table 420 includes fields representing "location" indicating the installation location of the solar power generation facility 300, "tilt angle" representing the installation angle of the panels of the solar power generation facility 300, "installation azimuth angle" representing the orientation of the panels of the solar power generation facility 300, "type" representing the type of the solar power generation facility 300, "panel capacity" representing the capacity of the panels of the solar power generation facility 300, "power conditioner capacity" indicating the capacity of the power conditioner, and each field indicating a coefficient (hereinafter, "fixed coefficient") set according to the facility type or the like in consideration of changes over time and losses, etc.

[0044] Subsequently, an example of the coefficient table 430 is shown in FIG. 7.

[0045] In the coefficient table 430, the actual value of the power generation amount at time point i, the estimated value corresponding to this actual value, and the first index value as an index value representing the degree of deviation between these are recorded for a plurality of time points i. The time point i represents a first period, which is a period in which the operation state estimation device 100 periodically estimates the operation state of the photovoltaic power generation facility 300, and each first period is distinguished by the identifier i. In this embodiment, as an example, since the operation state of the photovoltaic power generation facility 300 is estimated daily, the first period is one day. By performing the estimation of the operation state on a daily basis, it is possible to prevent an incorrect determination of the operation state due to a temporary (for example, about several tens of minutes) change in the state of the photovoltaic power generation facility 300, and to accurately estimate the operation state. For example, the solar irradiance at the installation location of the photovoltaic power generation facility 300 changes greatly even if the position and thickness of the clouds passing under the sun are slightly different, and the degree of deviation between the actual value and the estimated value of the power generation amount fluctuates greatly temporarily. Even in such a case, by setting the first period to one day, the fluctuation of the first index value can be suppressed, and it becomes possible to correctly estimate the operation state of the photovoltaic power generation facility 300. In addition to the one-day unit, the first period can be appropriately determined according to the cycle of estimating the state of the photovoltaic power generation facility 300, such as in units of 12 hours, one week, 10 days, one month, etc.

[0046] The method for obtaining the first index value is not particularly limited as long as a value representing the degree of deviation between the actual value and the estimated value of the power generation amount of the photovoltaic power generation facility 300 is obtained. In this embodiment, after obtaining the shortage amount of the actual value with respect to the estimated value of the power generation amount of the photovoltaic power generation facility 300 in the first period, the ratio of the shortage amount with respect to the estimated value is used as the first index value. Expressed by formulas, it is as follows in (1) to (4) below.

[0047] Actual value = total amount of actual power generation amount in the first period …(1) Estimated value = total amount of calculated power generation amount in the first period …(2) Shortage amount = MAX(estimated value - actual value, 0) …(3) First index value = shortage amount / estimated value …(4)

[0048] By calculating the first index value in this way, it becomes possible to appropriately determine the degree of deviation between the actual value and the estimated value of the power generation amount regardless of the magnitude of the power generation amount.

[0049] In addition, the estimated value of the power generation amount of the photovoltaic power generation facility 300 is calculated using the calculation formula 440 and the meteorological data represented by, for example, the following formulas (5) to (8).

[0050] Tpa = Ta+(A / (B×V 0.8 +1)+2)×Ga - 2 …(5) (Tpa: Solar cell panel temperature (°C), Ta: Ambient temperature (°C), A: Coefficient (for example, rooftop type “50”), B: Coefficient (for example, rooftop type “0.38”), V: Wind speed (m / s), Ga: Inclined surface solar irradiance (kW / m 2 ))

[0051] Kpt = 1 + αmax×(Tpa - 25) …(6) (Kpt: Temperature correction coefficient, αmax: Maximum power temperature coefficient (1 / °C), Tpa: Solar cell panel temperature (°C))

[0052] System output coefficient = Kloss × Kpt …(7) (Kloss: Temporal change (dirt, deterioration), wiring resistance loss, inverter loss, etc., a fixed coefficient generally used according to the equipment type, etc. to consider these, Kpt: Temperature correction coefficient)

[0053] Estimated value = Inclined surface solar irradiance (Ga) × System output coefficient × Panel capacity …(8) In addition, the calculation formula 440 for calculating the estimated value of the power generation amount of the photovoltaic power generation facility 300 is not limited to the above (5) to (8).

[0054] For example, a learning model may be generated by learning the relationship between past actual power generation values and weather data of a predetermined type, and an estimated value of the power generation amount may be calculated by inputting the weather data of the target day for estimating the power generation amount into this learning model. In this case, the learning model may be a model generated by deep learning of artificial intelligence using CNN (Convolution Neural Network) or the like, or may be a learning model using a regression formula. The learning model generated in this way is also included in the calculation formula 440. In such a manner, it becomes possible to more accurately calculate the estimated value of the power generation amount of the solar power generation facility 300 that is greatly affected by weather data and changes.

[0055] Alternatively, an adjustment coefficient (for example, actual value / estimated value) representing the error between the actual power generation value for each day in a past predetermined period and the estimated value of the power generation amount for each of these days calculated using the above (5) to (8) is obtained, and the average value of these adjustment coefficients is multiplied by the estimated value of the target day for estimating the power generation amount calculated using the formulas (5) to (8), so that the estimated value of the power generation amount may be corrected. In this case, in addition to the formulas (5) to (8), the formula for calculating the adjustment coefficient for each day, the formula for calculating the average value of the adjustment coefficients, and the formula for correcting the estimated value of the power generation amount are also included in the calculation formula 440.

[0056] In such a manner, it becomes possible to cancel the influence of the error generation factors caused by the formulas (5) to (8) and more accurately calculate the estimated value of the power generation amount of the solar power generation facility 300.

[0057] Furthermore, at this time, according to the difference (temperature difference) between the above-mentioned daily weather data of a predetermined type (such as temperature) and the weather data on the target day for estimation, the above-mentioned daily adjustment coefficients may be weighted and averaged, and the estimated value of the power generation amount on the target day for estimation may be corrected by multiplying the weighted average adjustment coefficient. In this case, in addition to the formulas (5) to (8), the formula for calculating the adjustment coefficient for each day, the formula for calculating the weighted average value of the adjustment coefficients, and the formula for correcting the estimated value of the power generation amount are included in the calculation formula 440.

[0058] In this manner, the influence of the error factors caused by the formulas (5) to (8) is canceled out, and the adjustment coefficient is weighted-averaged with a larger weight for days when the value of the meteorological data is closer to the value on the estimation target day. Therefore, the influence of the meteorological data on the power generation amount can be considered, and the estimated value of the power generation amount of the solar power generation facility 300 can be calculated more accurately.

[0059] Returning to FIG. 2, the storage device 140 can be incorporated in the operating state estimation device 100 or can be externally attached.

[0060] The recording medium reading device 170 reads programs and data recorded on a recording medium 800 such as a CD-ROM or a DVD and stores them in the storage device 140.

[0061] The communication device 130 exchanges data and programs with other computers such as the solar power generation facility 300 (smart meter) and the meteorological data providing device 200 via a network 500 such as the Internet or a LAN (Local Area Network). For example, the above-described operating state estimation device control program 600 can be stored in another computer (not shown), and the operating state estimation device 100 can download and execute the operating state estimation device control program 600 from this computer.

[0062] Alternatively, the communication device 130 periodically receives the actual value of the power generation amount and various meteorological data such as temperature, precipitation, and solar radiation amount from the solar power generation facility 300 (smart meter) and the meteorological data providing device 200. Also, the operating state estimation device 100 may not include the storage device 140 and may use various data such as the above-described programs and tables stored in another computer (not shown) communicably connected through the network 500 to realize the function as the operating state estimation device 100.

[0063] The input device 150 is a device used for data input to the operation state estimation device 100 by an operator or the like, and functions as a user interface. As the input device 150, for example, a keyboard, a mouse, a microphone, etc. can be used.

[0064] The output device 160 is a device for outputting information to the outside and functions as a user interface. As the output device 160, for example, a display, a printer, a speaker, etc. can be used.

[0065] <Functional configuration> FIG. 8 shows a functional block diagram of the operation state estimation device 100 according to the present embodiment. The operation state estimation device 100 includes functions of a calculation formula storage unit 101, a weather data acquisition unit 102, a first index value calculation unit 103, an operation state estimation unit 104, and a determination value calculation unit 105. These functions are realized by executing or processing the operation state estimation device control program 600 according to the present embodiment and various data by the hardware shown in FIG. 2.

[0066] [Calculation formula storage unit] The calculation formula storage unit 101 stores a calculation formula 440 for calculating an estimated power generation amount of the solar power generation facility 300 from predetermined types of weather data including solar radiation amount. In the present embodiment, the calculation formula storage unit 101 is embodied as the storage device 140. The calculation formula 440 is exemplified by the above-described formulas (5) to (8) and the like.

[0067] [Weather data acquisition unit] The weather data acquisition unit 102 acquires weather data from the weather data providing device 200 connected communicably. In the present embodiment, the weather data acquisition unit 102 is embodied as the communication device 130 that acquires MSM data from the weather data providing device 200.

[0068] [First index value calculation unit] The first index value calculation unit 103 calculates a first index value representing the degree of deviation between the estimated value and the actual value based on the estimated value of the power generation amount of the solar power generation facility 300 in the first period calculated using the weather data and the calculation formula 440, and the actual value of the power generation amount of the solar power generation facility 300 in the first period, for each first period in which the operating state of the solar power generation facility 300 is periodically estimated.

[0069] For example, the first index value calculation unit 103 obtains the shortage amount of the actual value with respect to the estimated value of the power generation amount of the solar power generation facility 300 in the first period, and calculates the ratio of the shortage amount with respect to the estimated value of the power generation amount as the first index value.

[0070] More specifically, the first index value calculation unit 103 calculates an estimated value of the power generation amount for one day using the MSM data and the calculation formula 440 every day, and calculates a first index value representing the degree of deviation between the estimated value of the power generation amount and the actual value of the power generation amount for one day obtained from the power generation amount actual value table 410 using formulas (1) to (4).

[0071] Then, the first index value calculation unit 103 stores the first index value in the coefficient table 430 described above.

[0072] Note that the first index value may be other values such as the difference between the estimated value and the actual value, or the square of the difference, as long as it represents the degree of deviation between the estimated value and the actual value of the power generation amount of the solar power generation facility 300.

[0073] [Operating state estimation unit] The operating state estimation unit 104 estimates the operating state of the solar power generation facility 300 based on the result of comparison between the first index value calculated for each of the above first periods and a predetermined determination value. In such a manner, the operating state estimation apparatus 100 according to the present embodiment can estimate the operating state of the solar power generation facility 300 without using a solar radiation sensor.

[0074] In addition, when the actual value or estimated value of the power generation amount of the solar power generation facility 300 is less than the first reference value, the operation state estimation unit 104 may not estimate the operation state of the solar power generation facility 300. By such a mode, it becomes possible to prevent an incorrect determination of the operation state of the solar power generation facility 300.

[0075] That is, a day when the actual value or estimated value of the power generation amount of the solar power generation facility 300 is less than the first reference value is a day with little solar radiation, such as a day with bad weather and dim light throughout the day. On such a day, both the actual value and the estimated value of the power generation amount from the solar power generation facility 300 become small. Therefore, a slight fluctuation in the actual value and the estimated value of the power generation amount will greatly vary the first index value. Therefore, if the operation state of the solar power generation facility 300 is estimated on such a dim day, it is likely to cause an incorrect determination. The first reference value is determined so as to be able to exclude a day with little solar radiation on which an incorrect determination of the operation state of such a solar power generation facility 300 is likely to occur. The first reference value can be determined, for example, as 20%, 40%, 50%, 60% of the rated value of the solar power generation facility 300, or 50% of the maximum estimated value in a past predetermined period (for example, 100 days). The first reference value may also be determined by the administrator of the solar power generation facility 300. By such a mode, it becomes possible to change the sensitivity of the estimation of the operation state of the solar power generation facility 300 according to the circumstances of the administrator.

[0076] Alternatively, the administrator may be able to individually specify a day (first period) when the operation state estimation device 100 does not estimate the operation state of the solar power generation facility 300. For example, at the request of an electric power company or the like, it is advisable to individually specify and exclude a day (first period) when the power generation amount of the solar power generation facility 300 is intentionally suppressed. By such a mode, since it is possible to exclude a day (first period) in which it is known in advance that the deviation between the estimated value and the actual value of the power generation amount will increase, it becomes possible to correctly estimate the operation state of the solar power generation facility 300.

[0077] Further, when the first index value in the first period exceeds the determination value, the operation state estimation unit 104 may be configured to estimate that the operation state of the solar power generation facility 300 is an output decrease state in the first period.

[0078] And when the operation state estimation device 100 estimates that the solar power generation facility 300 is in an output decrease state, as a precaution, it may be configured to transmit information to prompt the user through the smart meter. With such an aspect, for example, the user can check the solar power generation facility 300 to see if the solar panels are covered by light-blocking flying objects.

[0079] In this way, when the first index value becomes larger than the determination value, instead of immediately estimating a state such as an abnormal output decrease state or a failure occurrence, by once estimating a state of an output decrease state, it is possible to prevent misjudging a mere temporary change in the operation state as an abnormality.

[0080] And when the first period in which the operation state of the solar power generation facility 300 is estimated to be in an output decrease state continues for a predetermined number of times (predetermined number of days), the operation state estimation unit 104 may be configured to estimate the operation state of the solar power generation facility 300 as an abnormal output decrease state. With such an aspect, the operation state estimation device 100 can more reliably estimate the abnormal output decrease state of the solar power generation facility 300. In this embodiment, when the output decrease state continues twice in a row (that is, when it continues for two days in a row), it is estimated that an abnormal output decrease state has occurred, but the number of times can be appropriately set to any number. The administrator of the solar power generation facility 300 may be able to set this number of times. With such an aspect, it is possible to change the sensitivity of failure detection according to the circumstances of the administrator of the solar power generation facility 300.

[0081] In addition, when the operation state estimation device 100 estimates that the photovoltaic power generation facility 300 is in an abnormal output reduction state, it may transmit an alarm to the administrator through the smart meter. In such a manner, the administrator can be aware of the abnormal change in the power generation amount of the photovoltaic power generation facility 300 and can take measures such as requesting inspection and repair of the photovoltaic power generation facility 300.

[0082] Of course, when the first index value in the first period exceeds the determination value, the operation state estimation unit 104 may estimate that the operation state of the photovoltaic power generation facility 300 is in an abnormal output reduction state in the first period. In such a manner, the operation state estimation device 100 can quickly detect the abnormal change in the photovoltaic power generation facility 300 and notify the administrator.

[0083] Next, the determination value calculation unit 105 will be described. The determination value calculation unit 105 calculates the average value m and the standard deviation σ of the first index value in a past predetermined period (for example, 100 days), and calculates the above-described determination value based on the average value m and the standard deviation σ.

[0084] For example, the determination value calculation unit 105 calculates the determination value by adding the value obtained by multiplying the standard deviation σ by a positive constant k to the average value m.

[0085] That is, the determination value calculation unit 105 can calculate the determination value as shown in the following formula (9). Determination value = m + k×σ…(9)

[0086] In such a manner, the operation state estimation device 100 determines whether there is an abnormal change in the power generation amount based on the result of statistically verifying the first index value representing the degree of deviation between the estimated value and the actual value of the power generation amount of the photovoltaic power generation facility 300 on the determination target day using a plurality of first index values in a past predetermined period. Thereby, it becomes possible to more accurately estimate the operation state of the power generation amount of the photovoltaic power generation facility 300. That is, when determining the operation state of the photovoltaic power generation facility 300 without using a solar radiation sensor, it is possible to appropriately set a determination value that does not result in a misjudgment.

[0087] For example, when the positive constant k is 2, the probability that the first index value on the determination target date exceeds the determination value is about 5%. When the positive constant k is 3, the probability that the first index value on the determination target date exceeds the determination value is about 0.3%. Also, the value of the positive constant k may be a positive real number, not limited to natural numbers as long as it is a positive value.

[0088] Further, when calculating the determination value, the determination value calculation unit 105 may exclude the first index values in the first period in which the actual or estimated power generation amount of the solar power generation facility 300 is less than the second reference value among the first index values in a past predetermined period, and calculate the average value m and the standard deviation σ. In such a manner, it is possible to calculate a determination value that can more appropriately estimate the operating state of the solar power generation facility 300.

[0089] That is, a day when the actual or estimated power generation amount of the solar power generation facility 300 is less than the second reference value is a day with little solar irradiance, such as a day with bad weather and low light all day. On such a day, both the actual and estimated power generation amounts from the solar power generation facility 300 are small, so a slight fluctuation in the actual and estimated power generation amounts will cause a large variation in the first index value. Therefore, the first index value calculated on such a dull day is likely to be a large value, and the determination value has to be set to a large value.

[0090] Then, it becomes difficult for the first index value to exceed the determination value. For example, it may occur that the state of the solar power generation facility 300 cannot be detected even though the power generation amount of the solar power generation facility 300 has actually decreased abnormally, etc., and there is a possibility that the state estimation of the solar power generation facility 300 cannot be correctly performed.

[0091] Therefore, when the actual or estimated power generation amount of the solar power generation facility 300 is less than the second reference value, the determination value calculation unit 105 according to this embodiment calculates the determination value excluding the first period. At this time, the second reference value is determined so that a determination value that makes it difficult to appropriately estimate the operating state of the solar power generation facility 300 is not calculated. The second reference value may be the same as the first reference value or may be a different value. For example, the second determination value can be determined as 20%, 40%, 50%, 60% of the rated value of the solar power generation facility 300, or 50% of the maximum estimated value in a past predetermined period (for example, 100 days). Also, the second reference value may be determined by the administrator of the solar power generation facility 300. With such an aspect, it becomes possible to change the sensitivity of estimating the operating state of the solar power generation facility 300 according to the circumstances of the administrator.

[0092] In addition, when there is a day (first period) excluded so as not to estimate the operating state of the solar power generation facility 300, the determination value calculation unit 105 may exclude the first index value of that day when calculating the determination value. With such an aspect, it becomes possible to calculate the determination value more appropriately.

[0093] Note that the determination value calculation unit 105 obtains the determination value using the first index value in a past predetermined period. However, this predetermined period does not have to be a continuous period, for example, as shown in FIG. 13.

[0094] As shown in FIG. 13, the past predetermined period is, for example, the most recent 14 days up to the current day (the day for estimating the operating state), the day one year ago from the current day and 14 days before and after it, and further, the day two years ago from the current day and 14 days before and after it, and the day three years ago from the current day and 14 days before and after it may be included. However, the above is merely an example, and any period with the same weather conditions as the current day is acceptable. With such an aspect, since the operating state can be estimated using past data with similar weather conditions that affect the power generation amount of the solar power generation facility 300, it becomes possible to improve the accuracy.

[0095] ==Processing flow== Next, while referring to FIGS. 9 to 10, the operation state estimation device 100 according to the present embodiment will be described with reference to the above-described weather data table 400, power generation amount actual value table 410, facility table 420, coefficient table 430, and calculation formula 440, and the flow of processing when estimating the operation state of the power generation amount of the solar power generation facility 300 will be described.

[0096] First, for example, when a predetermined time (for example, 21:00) after sunset every day arrives, the operation state estimation device 100 acquires the weather data and the actual value of the power generation amount for that day (S1000). Specifically, the operation state estimation device 100 acquires the actual value of the power generation amount of the solar power generation facility 300 at a predetermined time during the day (for example, from 6:00 to 18:00) on that day from the power generation amount actual value table 410. Further, the operation state estimation device 100 acquires weather data including the solar radiation amount at the same time (from 6:00 to 18:00) from the weather data table 400.

[0097] At this time, the operation state estimation device 100 acquires three pieces (for three hours) of weather data (the three pieces of weather data close to each distribution time marked with a star in FIG. 4) out of the weather data distributed as MSM data every three hours, which are close to each distribution time.

[0098] And when the total value of the actual values of the power generation amount is less than the first reference value, the operation state estimation device 100 ends the process without estimating the operation state of the solar power generation facility 300 (S1010).

[0099] On the other hand, when the total of the actual values of the power generation amount is equal to or greater than the first reference value, the operation state estimation device 100 calculates an estimated value of the power generation amount of the solar power generation facility 300 at the above-described predetermined time on that day using the weather data and the calculation formula 440 (S1020).

[0100] And the operation state estimation device 100 calculates the first index value for that day based on the above-described formulas (1) to (4) (S1030).

[0101] If the first index value is less than or equal to the determination value, the operating state estimation device 100 estimates that the operating state of the solar power generation facility 300 is normal (no abnormality), and ends the process (S1040).

[0102] On the other hand, if the first index value exceeds the determination value, the operating state estimation device 100 checks whether the first index value also exceeded the determination value the previous day (S1050). Then, if the first index value did not exceed the determination value the previous day, the operating state estimation device 100 determines that the operating state of the solar power generation facility 300 is in an output reduction state (S1060). Also, if the first index value also exceeded the determination value the previous day, the operating state estimation device 100 determines that the operating state of the solar power generation facility 300 is in an abnormal output reduction state (S1060).

[0103] In such a manner, the operating state estimation device 100 according to the present embodiment can estimate the operating state of the solar power generation facility 300 without using a solar radiation sensor.

[0104] On the other hand, the operating state estimation device 100 performs a process of determining the above-described determination value according to the procedure shown in FIG. 10.

[0105] First, the operating state estimation device 100 acquires the first index value in a past predetermined period (for example, 100 days) (S2000). For example, the operating state estimation device 100 acquires the first index value for the past 100 days from the coefficient table 430.

[0106] Then, after the operating state estimation device 100 excludes the first index value on days when the actual power generation amount of the solar power generation facility 300 is less than the second reference value (S2010), it calculates the average value m and the standard deviation σ of the first index value for the remaining days, and obtains the determination value using Equation (9) (S2020).

[0107] In such a manner, when determining the operating state of the solar power generation facility 300 without using a solar radiation sensor, it is possible to appropriately set a determination value that does not result in a misjudgment.

[0108] Next, with reference to FIGS. 11 and 12, the operation of the operating state estimation device 100 according to the present embodiment for estimating the operating state of the photovoltaic power generation facility 300 will be described.

[0109] FIGS. 11 and 12 are examples of screens displayed on an output device such as a display of a computer (not shown) such as a personal computer or a smartphone owned by the administrator of the photovoltaic power generation facility 300, for example, by the operating state estimation device 100.

[0110] FIG. 11 is a graph showing the estimated values and actual values of the daily power generation amounts of the photovoltaic power generation facility 300 in a certain past predetermined period as the positions of points on a two-dimensional coordinate plane with the estimated values on the horizontal axis and the actual values on the vertical axis.

[0111] In FIG. 11, the straight line indicated by (D) represents the case where the estimated value and the actual value are equal. When the position of the point is on the straight line (D), according to formulas (1) to (4), the first index value becomes 0. Although there are points in FIG. 11 where the actual value is larger than the straight line (D), the first index value also becomes 0 when calculated using formulas (1) to (4) for such points.

[0112] Also, in FIG. 11, the straight line indicated by (G) represents the first reference value (minimum output). Therefore, as shown by the white circles in FIG. 11, when the position of the point is smaller (to the left) than the straight line (G), the operating state estimation device 100 does not estimate the operating state of the photovoltaic power generation facility 300. In the example shown in FIG. 11, the minimum output indicated by the straight line (G) is defined as 50% of the maximum output indicated by the straight line (C).

[0113] Also, in the present embodiment, the first reference value and the second reference value are set to the same value, and the straight line (G) also represents the second reference value. Therefore, the operating state estimation device 100 calculates the determination value without using the first index value for days when the position of the point is smaller (to the left) than the straight line (G), as shown by the white circles in FIG. 11.

[0114] In addition, the points indicated by the white triangles in FIG. 11 indicate that the output of the solar power generation facility 300 has been suppressed at the request of an electric power company or the like. For this reason, when the actual value of the power generation amount is artificially decreased in this way, the operation state estimation device 100 does not estimate the operation state of the solar power generation facility 300.

[0115] In addition, the points indicated by the white squares in FIG. 11 indicate that, for example, on a day when it was sunny in the afternoon after snowfall in the morning, it has been found that the actual value of the power generation amount of the solar power generation facility 300 is lower than the estimated value. The operation state estimation device 100 according to the present embodiment also does not estimate the operation state of the solar power generation facility 300 in such a case.

[0116] Then, the operation state estimation device 100 calculates the average value m of the first index values calculated for each of the points indicated by the black circles shown in FIG. 11, thereby calculating the average value m of the ratio (deficiency rate) of the deficiency amount of the actual value with respect to the estimated value. In FIG. 11, the straight line (E) is a straight line determined by calculating the value of the formula (10) using the average value m calculated in this way. Estimated value × (1 - average value m) … (10)

[0117] Similarly, the operation state estimation device 100 calculates the standard deviation σ of the first index values calculated for each of the points indicated by the black circles shown in FIG. 11, thereby calculating the standard deviation σ of the ratio (deficiency rate) of the deficiency amount of the actual value with respect to the estimated value. In FIG. 11, the straight line (F) is a straight line determined by calculating the value of the formula (11) using the average value m and the standard deviation σ calculated in this way. Estimated value × (1 - (average value m + k × σ)) … (11) Note that k is a positive constant, for example, 3.

[0118] Then, the operation state estimation device 100 determines that the points within the region indicated by (A) in FIG. 11 are normal, and the points within the region indicated by (B) are in an output decrease state or an output abnormally decrease state.

[0119] On the other hand, FIG. 12 is the same as the example shown in FIG. 11, but the administrator of the solar power generation facility 300 can freely set days when the values of the above-described first reference value and second reference value (corresponding to the straight line (G)), the value of the standard deviation σ (corresponding to the straight line (F)), or days when the estimation of the operating state is not performed as shown by the white triangles and white squares. This is an example of such a case.

[0120] With such an aspect, for example, due to differences in weather conditions depending on the installation area and season of the solar power generation facility 300 (for example, in winter, a lot of snow accumulates on the panels and the power generation amount is extremely small even on sunny days), differences in sunlight conditions (for example, there are large trees in front of the house and the sunlight is poor), etc., it is possible to consider various different situations for each household and estimate the operating state of the solar power generation facility 300 optimally for each household.

[0121] As described above, the operating state estimation device 100, the control method of the operating state estimation device 100, and the operating state estimation device control program 600 according to the present embodiment have been described. According to the present embodiment, it is possible to estimate the operating state of the solar power generation facility 300 without using a solar radiation sensor. As a result, it is possible to estimate the operating state even for a relatively low-cost solar power generation facility 300 such as for general households, and it is possible to quickly notify the user of an abnormality. In general households, even if the solar power generation facility 300 fails and the power generation amount decreases, the shortfall is compensated by the power supplied by the electricity retailer, and there is no problem in daily life, so it is difficult to notice the failure of the solar power generation facility 300. Therefore, the electricity bill may increase without the user's knowledge, and in some cases, it may affect the household budget over a long period of time.

[0122] If, as in the present embodiment, it is possible to estimate the operating state of the solar power generation facility 300 without using a solar radiation sensor, it is possible to improve the convenience of the user while suppressing the cost.

[0123] In particular, according to the present embodiment, by statistically verifying a first index value representing the degree of deviation between the estimated value and the actual value of the power generation amount of the solar power generation facility 300 on the estimation target date of the operating state, using a plurality of first index values in the past predetermined period, it becomes possible to determine whether or not there is an abnormal change in the power generation amount. As a result, it becomes possible to more accurately estimate the operating state of the power generation amount of the solar power generation facility 300. That is, when determining the operating state of the solar power generation facility 300 without using a solar radiation sensor, it becomes possible to appropriately set a determination value that does not result in an incorrect determination.

[0124] Note that the above-described embodiments are for facilitating the understanding of the present invention and are not for limiting the interpretation of the present invention. The present invention can be changed and improved without departing from its gist, and equivalents thereof are also included in the present invention.

Explanation of Reference Numerals

[0125] 100 Operating state estimation device 101 Calculation formula storage unit 102 Weather data acquisition unit 103 First index value calculation unit 104 Operating state estimation unit 105 Determination value calculation unit 110 CPU 120 Memory 130 Communication device 140 Storage device 150 Input device 160 Output device 170 Recording medium reading device 200 Weather data providing device 300 Solar power generation facility 400 Weather data table 410 Power generation amount actual value table 420 Facility table 430 Coefficient table 440 Calculation formula 500 Network 600 Operating state estimation device control program 800 Recording medium 1000 Operating State Estimation System

Claims

1. An operating state estimation device for estimating the operating state of a photovoltaic power generation facility, comprising: a calculation formula storage unit that stores a calculation formula for calculating an estimated value of the power generation amount of the photovoltaic power generation facility from predetermined types of meteorological data including solar irradiance; a meteorological data acquisition unit that acquires the meteorological data from a meteorological data providing device connected communicably; For each first period in which the operating state of the photovoltaic power generation facility is periodically estimated, an estimated value of the power generation amount of the photovoltaic power generation facility in the first period calculated using the meteorological data and the calculation formula, and an actual value of the power generation amount of the photovoltaic power generation facility in the first period, a first index value calculation unit that calculates a first index value representing the degree of deviation between the estimated value and the actual value based on the above; a determination value calculation unit that calculates an average value and a standard deviation of the first index value in a past predetermined period, and calculates a determination value based on the average value and the standard deviation; an operating state estimation unit that estimates the operating state of the photovoltaic power generation facility based on the result of comparison between the first index value and the determination value; and comprising An operating state estimation device that displays, on a two-dimensional coordinate plane in which the estimated value of the power generation amount corresponds to a first coordinate axis and the actual value of the power generation amount corresponds to a second coordinate axis, a region representing the operating state of the photovoltaic power generation facility and a point determined from the estimated value and the actual value of the power generation amount in the first period.

2. The operating state estimation device according to claim 1, wherein the first index value calculation unit obtains an amount of shortage of the actual value with respect to the estimated value of the power generation amount of the photovoltaic power generation facility in the first period, and calculates the ratio of the amount of shortage with respect to the estimated value as the first index value in the first period. An operating state estimation device.

3. The operating state estimation device according to claim 2, wherein the operating state estimation unit When the first index value in the first period exceeds the determination value, estimates that the operating state of the photovoltaic power generation facility is an abnormal output decrease state in the first period. An operating state estimation device.

4. The operating state estimation device according to claim 2, wherein the operating state estimation unit When the first index value in the first period exceeds the determination value, it is estimated that the operating state of the solar power generation facility is an output decrease state in the first period. Further, when the first periods in which the operating state of the solar power generation facility is estimated to be the output decrease state continue for a predetermined number of times, the operating state of the solar power generation facility is estimated to be an abnormal output decrease state. An operating state estimation device.

5. The operating state estimation device according to any one of claims 1 to 4, wherein the operating state estimation unit, when the actual value or estimated value of the power generation amount of the solar power generation facility is less than a first reference value, does not estimate the operating state of the solar power generation facility. An operating state estimation device.

6. The operating state estimation device according to any one of claims 1 to 5, wherein the length of the first period is one day, An operating state estimation device.

7. The operating state estimation device according to any one of claims 1 to 6, wherein the determination value calculation unit, excludes the first index value in the first period in which the actual value or estimated value of the power generation amount of the solar power generation facility is less than a second reference value among the first index values in the predetermined period, and calculates the average value and the standard deviation. An operating state estimation device.

8. The operating state estimation device according to any one of claims 1 to 7, wherein the determination value calculation unit calculates the determination value by adding a value obtained by multiplying the standard deviation by a positive constant to the average value, An operating state estimation device.

9. A control method for an operating state estimation device that estimates the operating state of a solar power generation facility, wherein the operating state estimation device, stores a calculation formula for calculating an estimated value of the power generation amount of the solar power generation facility from predetermined types of meteorological data including solar radiation amount, acquires the meteorological data from a meteorological data providing device connected communicably, for each first period in which the operating state of the solar power generation facility is periodically estimated, based on the estimated value of the power generation amount of the solar power generation facility in the first period calculated using the meteorological data and the calculation formula, and the actual value of the power generation amount of the solar power generation facility in the first period, calculates a first index value representing the degree of deviation between the estimated value and the actual value, calculates the average value and standard deviation of the first index value in a past predetermined period, calculates a determination value based on the average value and the standard deviation, estimates the operating state of the solar power generation facility based on the result of comparison between the first index value and the determination value, On a two-dimensional coordinate plane in which the estimated power generation amount is made to correspond to the first coordinate axis and the actual power generation amount is made to correspond to the second coordinate axis, a region representing the operating state of the solar power generation facility and a point determined from the estimated power generation amount and the actual power generation amount in the first period are displayed. A control method for an operating state estimation device.

10. In a computer, A procedure for storing a calculation formula for calculating an estimated power generation amount of a solar power generation facility from predetermined types of meteorological data including solar radiation amount; A procedure for acquiring the meteorological data from a meteorological data providing device connected in a communicable manner; For each first period in which the operating state of the solar power generation facility is periodically estimated, based on the estimated power generation amount of the solar power generation facility in the first period calculated using the meteorological data and the calculation formula and the actual power generation amount of the solar power generation facility in the first period, a procedure for calculating a first index value representing the degree of deviation between the estimated value and the actual value; A procedure for calculating the average value and the standard deviation of the first index value in a past predetermined period and calculating a determination value based on the average value and the standard deviation; A procedure for estimating the operating state of the solar power generation facility based on the result of comparison between the first index value and the determination value; A procedure for displaying, on a two-dimensional coordinate plane in which the estimated power generation amount is made to correspond to the first coordinate axis and the actual power generation amount is made to correspond to the second coordinate axis, a region representing the operating state of the solar power generation facility and a point determined from the estimated power generation amount and the actual power generation amount in the first period; A program for causing the above to be executed.

Images