JP2015047030A - Photovoltaic power generation management device, photovoltaic power generation management system, photovoltaic power generation management method, program, recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photovoltaic power generation management device which allows for suitable management of photovoltaic power generation, while analyzing and understanding the factor of lowering the power generation amount with time in the photovoltaic power generation.SOLUTION: A photovoltaic power generation management device 16 includes a power generation efficiency calculation unit 51 for calculating the power generation efficiency Er(t) by using the electric energy generated by a photovoltaic power generation panel 21, a degree of idealness calculation unit 52 for calculating an ideal value E(t) of power generation efficiency by using the amount of solar radiation and the panel temperature of the photovoltaic power generation panel, and calculating the ratio of the power generation efficiency Er(t) calculated in the power generation efficiency calculation unit 51 and an ideal value E(t) as a degree of idealness α, and a determination unit 53 for determining whether or not the degree of idealness α is lowering with time.

Description

  The present invention relates to a photovoltaic power generation management device or the like that manages photovoltaic power generation.

  As a clean power generation method with a small environmental load, a solar power generation system that directly converts sunlight into electric power is known. Since the solar power generation system can supply electric power without transmission from the electric power company in the daytime, it can reduce the power usage fee paid to the electric power company. In addition, surplus power can be sent back to the power company's transmission line for sale, and the amount corresponding to the amount of power can be offset from the power usage fee. For this reason, monitoring systems for the purpose of grasping the amount of power generation, the amount of power sales, etc. have become widespread.

  In the photovoltaic power generation system, the amount of power generation may decrease due to a system failure or the like. Therefore, in the monitoring system as described above, a device that detects an abnormality when the amount of power generation has dropped significantly, and a database that monitors the time, weather conditions, etc. along with the amount of power generation, should be obtained. A system that detects and announces an abnormality by comparing the amount and the actual power generation amount has been devised (see, for example, Patent Documents 1 and 2).

Japanese Patent No. 4802046 JP 2002-305844 A

  In such an existing system, an abnormality is often detected when the amount of power generation is greatly reduced due to the occurrence of a local shade due to a failure of one of the system components or fallen leaves.

  However, factors that reduce power generation over time, such as accumulation of dirt such as dust and volcanic ash on panels, are not evaluated as needed, and are detected as abnormal only when the power generation falls below a certain value. The Such accumulated dirt is generally thought to fall due to rain in spite of the presence of volcanic ash and other materials that are difficult to fall off. The system did not judge, and it was difficult to perform maintenance at an appropriate maintenance time in terms of cost effectiveness.

  The present invention has been made in view of the above-described object, and it is possible to analyze a factor of a decrease in the amount of power generation in solar power generation and grasp a factor for decreasing the power generation amount over time, and management of solar power generation is suitably performed. An object is to provide a solar power generation management device that can be used.

  1st invention for solving the subject mentioned above uses the power generation efficiency calculation part which calculates power generation efficiency using the electric energy which the photovoltaic power generation panel generated, the amount of solar radiation, and the panel temperature of the photovoltaic power generation panel. An ideal value calculation unit that calculates an ideal value of power generation efficiency and calculates a ratio between the power generation efficiency calculated by the power generation efficiency calculation unit and the ideal value as an ideality, and whether the ideality has decreased over time It is a solar power generation management device characterized by having a judgment part which judges whether or not.

  According to the present invention, the ideality of power generation efficiency is calculated, and from the transition, factors that lower the ideality (that is, power generation amount) over time, such as the accumulation of panel dirt, can be quantitatively evaluated, and this is notified to the user. Therefore, management of solar power generation can be favorably performed by promoting appropriate measures.

It is desirable that the determination unit determine whether the ideality has increased after the rain using rainfall data indicating a temporal change in rainfall and the ideality.
As a result, it is possible to discriminate between the accumulation of minor panel dirt that falls in the rain and the accumulation of dirt that does not fall in the rain that are highly necessary for maintenance as the cause of the decrease in ideality, and by notifying the user, etc. Appropriate measures can be taken.

The solar power generation management device of the first invention preferably further includes a power generation amount prediction unit that calculates a predicted value of a future power generation amount using the change in the ideality.
As a result, it is possible to grasp the future power generation amount in consideration of a decrease in ideality, and to efficiently perform maintenance management and other management.

Moreover, the photovoltaic power generation management device according to the first aspect of the present invention calculates a predicted value of a future power generation amount when the ideality is restored by maintenance at a predetermined interval using the change in the ideality, and the power generation amount It is desirable to further have a maintenance time calculation unit that calculates a difference between the prediction value calculated by the prediction unit and calculates an optimum value of the maintenance time using the difference and the cost for one maintenance.
This makes it possible to calculate a maintenance time that optimizes cost effectiveness, and to notify the user.

When the determination unit does not determine that the ideality is decreasing with time, it is preferable to determine whether the ideality is equal to or less than a predetermined value for a predetermined time.
As a result, it is possible to grasp a situation in which the ideality is equal to or lower than a predetermined value for a certain time due to a system failure or the like, and appropriate measures can be taken by notifying the user.

  2nd invention is the electric energy measuring apparatus which measures the electric energy which the photovoltaic power generation panel generated, the solar radiation amount measuring apparatus which measures the amount of solar radiation, and the temperature measuring apparatus which measures the panel temperature of the said photovoltaic power generation panel, The solar power generation management device, the solar power generation management device, the power generation efficiency calculation unit that calculates the power generation efficiency using the power amount, and the power generation efficiency using the solar radiation amount and the panel temperature An ideal value is calculated, an ideality calculation unit that calculates a ratio between the power generation efficiency calculated by the power generation efficiency calculation unit and the ideal value as an ideality, and determines whether or not the ideality has decreased over time A photovoltaic power generation management system comprising:

  According to a third aspect of the present invention, the computer calculates the power generation efficiency using the amount of power generated by the solar power generation panel, and the power generation efficiency ideal using the solar radiation amount and the panel temperature of the solar power generation panel. An ideality calculation step of calculating a value, calculating a ratio between the power generation efficiency calculated in the power generation efficiency calculation step and the ideal value as an ideality, and determining whether or not the ideality has decreased over time And a determination step.

  According to a fourth aspect of the present invention, a power generation efficiency calculating step for calculating power generation efficiency using a power amount generated by a solar power generation panel in a computer; An ideality calculation step of calculating a value, calculating a ratio between the power generation efficiency calculated in the power generation efficiency calculation step and the ideal value as an ideality, and determining whether or not the ideality has decreased over time And a determination step.

  According to a fifth aspect of the invention, a power generation efficiency calculating step for calculating power generation efficiency using a power amount generated by a solar power generation panel in a computer, and an ideal power generation efficiency using a solar radiation amount and a panel temperature of the solar power generation panel. An ideality calculation step of calculating a value, calculating a ratio between the power generation efficiency calculated in the power generation efficiency calculation step and the ideal value as an ideality, and determining whether or not the ideality has decreased over time And a determination medium. A recording medium recording a program for executing the determination step.

  According to the present invention, it is possible to analyze a factor of a decrease in power generation amount in solar power generation and grasp a factor that decreases the power generation amount over time, and to provide a solar power generation management device and the like that can suitably manage solar power generation Can do.

The figure which shows the photovoltaic power generation management system 1 The figure which shows the hardware constitutions of the photovoltaic power generation management apparatus 16. The figure which shows the function structure of the photovoltaic power generation management apparatus 16. Diagram showing the relationship between panel temperature, solar radiation and power generation efficiency Flow chart showing the flow of solar power management method The figure which shows the example of change of ideality alpha typically Flow chart showing calculation processing of predicted power generation amount Flow chart showing maintenance time calculation processing Diagram showing calculation of maintenance time Diagram showing calculation of maintenance time Diagram showing calculation of maintenance time

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

(1. Solar power management system 1)
A photovoltaic power generation management system 1 according to an embodiment of the present invention will be described with reference to FIG. This photovoltaic power generation management system 1 is provided for managing the photovoltaic power generation system 2.

  The photovoltaic power generation system 2 converts sunlight into electricity and uses it as household power, and includes a photovoltaic power generation panel 21, a power line 23, a power conditioner 25, and the like.

  The photovoltaic power generation panel 21 arranges a plurality of photovoltaic cells in a panel shape, thereby converting the light energy of sunlight into electricity. For example, a semiconductor made of silicon or various inorganic compounds is used for the solar battery cell. The installation direction and installation angle of the photovoltaic power generation panel 21 are variously determined according to location conditions and the like.

  In the present embodiment, the photovoltaic power generation panels 21 are connected in series and in parallel, and DC power generated by these photovoltaic power generation panels 21 is sent to the power conditioner 25 through the power line 23.

  The power conditioner 25 converts DC power into AC power. The converted electricity is supplied as household power via a distribution board (not shown) or transmitted to an electric power company.

  In the solar power generation system 2, other appropriate devices such as an isolator and various converters can be added if necessary.

  The photovoltaic power generation management system 1 is provided to manage the photovoltaic power generation system 2 as described above. The solar power generation system 1 includes a watt-hour meter 11, a solar radiation meter 12, a thermometer 13, a rain gauge 14, a data logger 15, a solar power generation management device 16, and the like.

  The watt-hour meter 11 is a power amount measuring device that measures the amount of power (power generation amount) generated by the solar power generation panel 21. The watt hour meter 11 is not particularly limited as long as it is provided on the power line 23 and can measure the power amount.

  The solar radiation meter 12 is a solar radiation amount measuring device that measures a solar radiation amount (a solar radiation amount per unit area) as a light energy amount of sunlight. The pyranometer 12 is provided in the vicinity of the photovoltaic power generation panel 21, and the installation angle and the installation orientation are adjusted to the photovoltaic power generation panel 21. The solar radiation meter 12 is, for example, a global solar radiation meter, but is not limited thereto.

  The thermometer 13 is a temperature measuring device that measures the panel temperature of the photovoltaic power generation panel 21 and is not particularly limited as long as the panel temperature can be measured. Although the surface temperature of the photovoltaic power generation panel 21 is measured here, the present invention is not limited to this.

  The rain gauge 14 is a rainfall measuring device that measures rainfall. The rain gauge 14 is not particularly limited as long as it is provided in the vicinity of the photovoltaic power generation panel 21 and can measure the amount of rainfall.

  The watt-hour meter 11, the pyranometer 12, the thermometer 13, and the rain gauge 14 measure over time at predetermined intervals and transmit the measured data to the data logger 15. The data logger 15 acquires these data and records changes with time.

  In the present embodiment, data corresponding to the entire photovoltaic power generation panel 21 is measured by the watt-hour meter 11, the solar radiation meter 12, the thermometer 13, and the rain gauge 14. For example, the watt hour meter 11 measures the power generated in all the panels, and the thermometer 13 measures the average value of the panel temperatures of all the panels. Further, one pyranometer 12 and one rain gauge 14 are provided in the vicinity of the panel, thereby representing values relating to the entire photovoltaic power generation panel 21.

  However, the present invention is not limited to this, and for example, the watt hour meter 11, the solar radiation meter 12, the thermometer 13, and the rain gauge 14 measure data corresponding to a group (also referred to as strings) in which the photovoltaic power generation panels 21 are connected in series. It is also possible to measure data corresponding to individual photovoltaic power generation panels 21. In these cases, for example, in the case of the watt-hour meter 11 and the thermometer 13, the value for each string is measured or the value for each photovoltaic power generation panel 21 is measured. In the case of the pyranometer 12 or the rain gauge 14, it is installed near each string or each panel.

  By arranging a plurality of these devices, it is possible to identify the location where the abnormality in the power generation amount reduction of the system occurs. However, since the cost also increases, it is good to decide after taking these balances into consideration. In addition, in order to detect an abnormality in the power conditioner 15, an extra watt hour meter can be installed on the power line from the power conditioner 15 to the distribution board or the like.

  The photovoltaic power generation management device 16 detects an abnormality in the amount of power generation of the system or calculates a maintenance time based on data measured by the watt-hour meter 11, the solar radiation meter 12, the thermometer 13, and the rain gauge 14. .

(2. Solar power generation management device 16)
FIG. 2 shows an example of the hardware configuration of the photovoltaic power generation management device 16. In the photovoltaic power generation management device 16, for example, a control unit 161, a storage unit 162, a media input / output unit 163, a communication control unit 164, an input unit 165, a display unit 166, a peripheral device interface unit 167, etc. are connected via a bus 168. It can be realized with a general computer.

The control unit 161 includes a CPU, a ROM, a RAM, and the like.
The CPU calls a program stored in the storage unit 162, ROM, recording medium or the like to a work memory area on the RAM, executes it, drives and controls each unit connected via the bus 168, and the photovoltaic power generation management device 16 Execute the process. The ROM is a non-volatile memory and permanently holds a computer boot program, a program such as BIOS, data, and the like. The RAM is a volatile memory, and temporarily stores a program, data, and the like loaded from the storage unit 162, ROM, recording medium, and the like, and includes a work area used by the control unit 161 to perform various processes.

  The storage unit 162 is a hard disk drive or the like, and stores a program executed by the control unit 161, data necessary for program execution, an OS, and the like. As the program, for example, a program for detecting an abnormality in the amount of power generation reduction of the system or calculating a maintenance time in a procedure described later is stored.

The media input / output unit 163 inputs and outputs data, and includes a media input / output device such as a DVD drive.
The communication control unit 164 includes a communication control device, a communication port, and the like, and performs communication control with other devices via a network. The network may be wired or wireless.

The input unit 165 inputs data and includes, for example, a keyboard, a pointing device such as a mouse, and an input device such as a numeric keypad.
The display unit 166 is a display device such as a CRT monitor or a liquid crystal panel.

The peripheral device interface unit 167 is a port for connecting peripheral devices. The connection form with the peripheral device may be wired or wireless.
The bus 168 is a path that mediates transmission / reception of control signals, data signals, and the like between the respective units.

  FIG. 3A is a diagram illustrating a functional configuration of the photovoltaic power generation management device 16. The solar power generation management device 16 includes a power generation efficiency calculation unit 51, an ideality calculation unit 52, a determination unit 53, a power generation amount prediction unit 54, and a maintenance time calculation unit 55.

  The power generation efficiency calculation unit 51 calculates the power generation efficiency using the amount of power generated by the solar power generation panel 21.

  The ideality calculation unit 52 calculates an ideal value of power generation efficiency using the amount of solar radiation near the photovoltaic power generation panel 21 and the panel temperature, and the ratio between the power generation efficiency calculated by the power generation efficiency calculation unit 51 and the ideal value is calculated as the ideality. Calculate as

  The determination unit 53 determines whether the ideality of the system depends on whether the ideality has decreased over time, whether the ideality has increased after rainfall, whether the ideality has been below a predetermined value over time, or the like. The abnormality detection of the degree (that is, the power generation amount) and the cause of the abnormality are detected. Here, the decrease in ideality with time means that the ideality continues to decrease for a predetermined time. Similarly, the ideality being below a predetermined value over time means that the ideality is below a predetermined value for a predetermined time.

  The power generation amount prediction unit 54 calculates a predicted value of the future power generation amount using a change in ideality.

  The maintenance time calculation unit 55 calculates a predicted value of the future power generation amount when the ideality is restored by maintenance at a predetermined interval using the change in ideality, and the predicted value calculated by the power generation amount prediction unit 54 The optimum value of the maintenance time is calculated using this difference and the cost for one maintenance.

  In this embodiment, as shown in FIG. 3B, the storage unit 162 stores the panel area 1621, the correspondence 1622, the past solar radiation 1623, the past rainfall 1624, the predicted panel temperature 1625, the maintenance cost. 1626, the amount of money per unit power generation amount 1627, and the like are stored in advance.

  The panel area 1621 is an area where the solar power generation panel 21 receives sunlight. In the present embodiment, since the entire photovoltaic power generation panel 21 is managed, the total panel area of each photovoltaic power generation panel 21 can be used as the panel area.

The correspondence relationship 1622 is data indicating the relationship between the solar radiation amount, the panel temperature, and the power generation efficiency of the solar power generation panel 21. Generally, the power generation efficiency E of the photovoltaic power generation panel 21 decreases as the panel temperature Tp increases as shown in FIG. 4A, and the solar radiation amount S peaks at a predetermined value as shown in FIG. 4B. As a result, it is known that the power generation efficiency is lowered even if it is more or less. Accordingly, such a correspondence relationship is determined in advance as a relational expression (1) of power generation efficiency E using the panel temperature Tp and the solar radiation amount S as variables based on the product specifications of the panel as described below. 162 is stored.
E = f (Tp, S) (1)

  The past solar radiation amount 1623 is, for example, data indicating a temporal change in the past solar radiation amount in the region, and can be determined for each region or season.

  The past rainfall 1624 is, for example, data indicating a temporal change in the past rainfall in the area, and in particular, in this embodiment, a rainfall interval in which a certain amount of rainfall has occurred is recorded. Past rainfall 1624 can also be determined for each region and season.

  The predicted panel temperature value 1625 is data indicating temporal changes such as seasonal variations and daily fluctuations in the panel temperature, and is obtained from simulation in consideration of the amount of solar radiation 1623 in the past.

  The maintenance cost 1626 is a cost required to perform maintenance of the photovoltaic power generation panel 21 once, and is determined according to the cause of a decrease in ideality.

  The amount 1627 per unit power generation amount is obtained by converting the unit power generation amount into a monetary amount.

(2. Solar power management method)
Next, a photovoltaic power generation management method for detecting abnormality of ideality reduction of the photovoltaic power generation system 2 and calculating maintenance time will be described. FIG. 5 is a flowchart illustrating a photovoltaic power generation management method by the photovoltaic power generation management system 1, and each step in the figure is executed by the control unit 161 of the photovoltaic power generation management device 16.

(S1: Acquisition of electric energy, solar radiation, panel temperature, rainfall)
In the present embodiment, while the photovoltaic power generation system 2 is in operation, the electric energy meter 11, the solar radiation meter 12, the thermometer 13, and the rain gauge 14 measure the electric energy, the solar radiation amount, the panel temperature, and the rainfall as described above. As shown in FIG. 5, the photovoltaic power generation management device 16 acquires these data via the data logger 15 (S1).

(S2: Calculation of power generation efficiency)
Next, the solar power generation management device 16 calculates the power generation efficiency (actually measured value) based on the amount of power and the amount of solar radiation (S2). The actual measurement value of the power generation efficiency can be calculated by the following equation (2), for example.
Er (t) = p (t) / (S (t) × A) (2)
Er (t) is an actual measurement value of power generation efficiency at time t. Also, p (t) is the amount of power at time t, S (t) is the amount of solar radiation at time t, and the value measured at S1 is used. A is the panel area, and the data stored in the storage unit 162 as described above is acquired and used.

  The power generation efficiency Er (t) calculated in S2 is displayed and recorded together with data such as the amount of power, the amount of solar radiation, the panel temperature, and the amount of rainfall acquired in S1.

(S3: Calculation of ideal value of power generation efficiency)
Next, the solar power generation management device 16 calculates an ideal value of power generation efficiency (S3). This ideal value is an ideal value of the power generation efficiency of the photovoltaic power generation panel 21 under the same conditions as the data of the solar radiation amount S (t) and the panel temperature Tp (t) at the time t acquired in S1, and the above formula Using (1)
E (t) = f (Tp (t), S (t)) (1 ′)
Can be calculated as E (t) is an ideal value of power generation efficiency at time t.

(S4: Calculation of ideality)
Next, the photovoltaic power generation management device 16 calculates the ideal degree of power generation efficiency (S4). This ideality indicates the ratio of the actual measurement value Er (t) of the current power generation efficiency calculated in S2 to the ideal value E (t) of the power generation efficiency calculated in S3, and is calculated by the following equation (3). it can.
α (t) = Er (t) / E (t) (3)
Here, α (t) is the ideal degree of power generation efficiency at time t.

  In this way, the ratio of the ideal value of the power generation efficiency to the actual measurement value is calculated as the ideality and used in the evaluation as will be described later, so that the effects of panel temperature and solar radiation on the evaluation can be ignored. Only the effects of abnormalities such as can be evaluated. As the ideal value of the power generation efficiency, it is also possible to use the maximum value of the actual measurement value of the power generation efficiency during the operation period of the solar power generation system 1 under the same conditions as the solar radiation amount and the panel temperature acquired in S1. is there.

(S5-S11: Abnormality detection and cause isolation)
Hereinafter, the solar power generation management device 16 performs abnormality detection of a decrease in ideality of the solar power generation system 1 based on the ideality α calculated in S4.

  This will be described with reference to FIG. 6A, 6 </ b> B, and 6 </ b> C are graphs schematically illustrating an example of the change in ideality α with time, with the horizontal axis representing time and the vertical axis representing ideality α and rainfall.

  That is, in the example of FIG. 6A, dirt such as light dust that falls due to rain accumulates on the photovoltaic power generation panel 21, and the ideality α decreases with time. However, as shown in a in the figure, when the rain falls, the dirt is removed and the ideality α is restored.

  In the example of FIG. 6B, the ideality α decreases with time because dirt such as volcanic ash that does not fall even when it rains accumulates on the photovoltaic power generation panel 21. In this case, the ideality α does not recover even if it rains as shown in FIGS.

  In the example of FIG. 6C, the ideality α is kept low for a certain period of time due to the occurrence of shade due to a system failure or fallen leaves.

In the present embodiment, the photovoltaic power generation management device 16 detects the abnormality in the ideality reduction as described above from the change in the ideality α, and the cause thereof is as follows. Panels that fall due to rain, etc. The ideality α decreases with time, but recovers due to rain (see Fig. 6 (a))
2. Panels that do not fall off due to rain, etc. Ideality α decreases with time and does not recover due to rain (see Fig. 6 (b))
3. A situation in which the ideality α remains low, such as a system failure or shade due to fallen leaves (see Fig. 6 (c))
And notify the user accordingly.

  That is, the photovoltaic power generation management device 16 uses the rainfall data acquired in S1 and the ideality α (t) calculated in S4, and continues for a certain period of time as shown in a period 34 in FIG. Although the ideality α decreases with time (S5; Yes), when it is determined that the ideality α has increased after raining (S6; Yes), the ideality may decrease over time due to the cause of recovery from rain, such as panel dirt that falls due to rain. If it is lowered (S7), the process proceeds to S12 described later.

  In the determination of S5 and S6, for example, a threshold value of a decrease width or an increase width is set in advance, and when the ideality decreases with time and the entire decrease width exceeds the threshold value, or after rain that exceeds the threshold value, When an increase in ideality is observed, it can be determined that the ideality has decreased over time or has increased after raining.

  On the other hand, as shown in the period 35 of FIG. 6B, the ideality α decreases with time for a certain period of time (S5; Yes), and the ideality 31 does not increase despite the rain ( If it is determined as S6; No), it is assumed that the ideality has decreased over time due to the reason that it does not recover due to rain, such as panel dirt that does not fall due to rain (S8), and the process proceeds to S12 described later.

  Further, as shown in the period 36 in FIG. 6C, the ideality α does not decrease with time for a predetermined time (S5; No), but the value of the ideality α itself is predetermined for a predetermined time. When it is determined that the value is equal to or less than the value (S9; Yes), it is assumed that a state of low ideality such as a failure of a system component has continued over time (S10), and the process proceeds to S12 described later.

  In cases other than the above (S5; No, S9; No), it is assumed that the system is normal and there is no problem (S11), and the process is terminated.

(S12: Calculation of predicted power generation)
In S12, the photovoltaic power generation management device 16 calculates a predicted value of the future power generation amount according to the cause of the decrease in the ideality using the change in the ideality α (S12). Details thereof will be described later.

(S13 to S15: Calculation of maintenance time and notification to user)
And the solar power generation management device 16 is a case where the ideality is reduced over time due to the reason that it does not recover due to rain, such as panel dirt that does not fall due to rain (S13; No), The predicted future power generation amount is notified to the user (S15), and the process is terminated. As countermeasures, for example, if the cause is to recover due to rain, notify that the ideality will recover due to rain, or if the low ideality continues, notify that the maintenance is urgently required Is desirable.

  In the case where the ideality decreases with time due to a panel stain that does not fall due to rain or the like (S13; Yes), the photovoltaic power generation management device 16 calculates an optimal maintenance time (S14). Details of this will be described later. Then, the user is notified of the cause of the decrease in ideality, the optimal maintenance time, the future predicted power generation amount, etc. (S15), and the process is terminated.

  Various notification methods in S15 are conceivable and are not particularly limited. For example, a home displayed on the display unit 166 of the photovoltaic power generation management device 16 or connected to the photovoltaic power generation management device 16 via a network (not shown). It can be displayed on a terminal in the network. In addition to these, it is possible to issue an alarm by turning on an attached lamp. Alternatively, an email may be transmitted from the photovoltaic power generation management device 16 to the user's mobile terminal.

  In addition to the above, the content of the notification may be the current ideality, the maintenance cost, the expected power generation amount obtained by carrying out the maintenance, the cost effectiveness, an appropriate comment, and the like. As described above, when data is measured for each string or each photovoltaic power generation panel 21, it is also possible to notify a location where the ideality is reduced.

  As described above, the photovoltaic power generation system 1 is managed by the photovoltaic power generation management system 2, and detection of abnormalities in the ideality reduction and isolation of the cause, calculation of future predicted power generation amount and optimum maintenance time, notification to the user, etc. Is done.

(3. Calculation of predicted power generation)
As described above, in S12, the future predicted power generation amount corresponding to the cause of the decrease in the ideality is calculated using the change in the ideality α. This will be described below. FIG. 7 is a flowchart showing a process for calculating the predicted power generation amount in the future.

  As shown in FIG. 7, in S12, the solar power generation management device 16 first acquires a past solar radiation amount 1623 from the storage unit 162 (S121). Then, in cases other than the case where the ideality decreases with time due to rain recovery, such as panel contamination (S122; No), the process proceeds to S124 described later.

  On the other hand, when the ideality decreases with time due to rain, such as panel stains (S122; Yes), the past rainfall amount 1624 is acquired from the storage unit 162 (S123) and will be described later. The process proceeds to S124.

  In S124, a future predicted power generation amount is calculated according to the cause of the decrease in ideality. This will be described below.

(3-1. In the case of panel stains that fall due to rain (S7))
In the case where the ideality decreases with time due to rain recovery such as a panel stain that falls due to rain, the photovoltaic power generation management device 16 in S124 in the period 34a before the rain as shown in FIG. A reduction width Δα of the ideality α per unit time is calculated.

Then, considering that the ideality α recovers during rain, the future ideality α (t) is calculated by the following formula (4), assuming that the future rainfall interval is the rainfall interval Δtrain determined from the past rainfall 1624. To do.
α (t) = α (t1) + g (Δα, Δtrain, t) (4)

  Note that t1 is the current time, and α (t1) indicates the current ideality. Further, g (Δα, Δtrain, t) is a function indicating a change in the ideality α in the future, and here, as indicated by a dotted line portion in the graph of FIG. 6A, the decrease in the ideality α at the inclination Δα. This is a saw-shaped function that repeats the recovery up to the maximum value (for example, 1) of the ideality α for each Δtrain.

  Then, the solar radiation amount 1623 in the past is acquired, the solar radiation amount average value Save for an appropriate period for calculating the power generation amount is calculated, and the predicted panel temperature value 1625 is acquired to obtain the panel temperature average value Tpave for the same period. Is calculated.

Then, the ideal value E of the future power generation efficiency is calculated from Save and Tpave using the above formula (1), and the power generation efficiency E (t) at the future time t is calculated using the following formula (5).
E (t) = α (t) × E (5)

Thereafter, the predicted power generation amount p (t) at a future time t is calculated by the following equation (6) using E (t) calculated by the equation (5).
p (t) = E (t) × Save × A (6)

  In the above procedure, the average value was used for the amount of solar radiation and the panel temperature. However, the present invention is not limited to this, and E (t) can also be determined in consideration of fine fluctuations such as daily fluctuations in the amount of solar radiation and panel temperature.

(3-2. Panel dirt that does not fall due to rain (S8))
In the case where the ideality has decreased with time due to the reason that the panel does not recover due to rain, etc., and does not recover due to rain, the photovoltaic power generation management device 16 per unit time in the period 35 shown in FIG. A reduction width Δα of the ideality α is obtained. Here, the decrease width Δα of the period 35a from the time of raining to the post-rainfall is obtained. However, the present invention is not limited to this, and it is sufficient that the decrease width per unit time in the period 35 can be obtained.

In this case, the future ideality α (t) can be calculated by the following equation (7). In equation (7), g (Δα, t) is a monotonically decreasing function of the slope Δα as shown by the dotted line in the graph of FIG. 6B.
α (t) = α (t1) + g (Δα, t) (7)

  Thereafter, as described above, the ideal value E of the future power generation efficiency is calculated from Save and Tpave, and the predicted power generation amount p (t) at the future time t is calculated by the above formulas (5) and (6).

(3-3. System failure, etc. (S10))
When the state of low ideality continues over time due to a system failure or the like, the photovoltaic power generation management device 16 continues the ideality α in the period 36 after this as shown by the dotted line portion in FIG. Then, the ideal value E of the future power generation efficiency is calculated from Save and Tpave as described above. Then, the power generation efficiency E (t) at a future time t is expressed by the following equation (5 ′) similar to the above equation (5).
E (t) = α · E (5 ′)
Calculated by Note that an average value in the period 36 can be used as the value of α, but is not limited thereto. For example, a value at the end of the period 36 may be used.

  Then, the predicted power generation amount p (t) at a future time t is calculated by the above equation (6).

(4. Calculation of maintenance time)
As described above, in the case where the ideality has decreased over time due to factors such as panel stains that do not fall due to rain, or the like, the optimal maintenance time is calculated in S14. This will be described below. FIG. 8 is a flowchart showing the calculation of the maintenance time.

  As shown in FIG. 8, in S14, the solar power generation management device 16 first acquires the maintenance cost 1626 per maintenance from the storage unit 162 (S141). Then, from the predicted value of the future power generation amount when the maintenance is performed at a predetermined interval and the maintenance cost 1626, an optimal maintenance time that maximizes the cost effectiveness is calculated (S142).

  In S142, various methods are conceivable. Here, first, an ideality αm (t) at a future time t when maintenance is performed at a predetermined interval, as indicated by a dotted line 41 in FIG. 9, is calculated. The solid line 41a in FIG. 9 indicates the ideality α (t) when maintenance is not performed, and the transition is the same as the dotted line portion of the graph in FIG. 6B.

In the present embodiment, as shown in FIG. 9, the ideality αm has a maximum value (for example, 1) by performing maintenance every maintenance time 43 that comes at a time interval Δt from the current time t1 (shown in 42 in the figure). Αm (t) is calculated by the following equation (8).
αm (t) = α (t1) + gm (Δα, Δt, t) (8)

  gm (Δα, Δt, t) is a function indicating a change in the ideality α in the future when maintenance is performed. Here, gm (Δα, Δt, t) is a slope Δα calculated in S12 as indicated by a dotted line 41 in the graph of FIG. This is a saw-shaped function that repeats the decrease in the ideality α and the recovery of the ideality α every Δt.

Thereafter, as described above, an ideal value E of the future power generation efficiency is calculated from Save and Tpave, and power generation at a future time t when maintenance is performed by the following equation (5 ″) similar to the above equation (5). The efficiency Em (t) is calculated.
Em (t) = αm (t) × E (5 ″)

Then, the predicted power generation amount pm (t) at a future time t when maintenance is performed is calculated by the following equation (6 ′) similar to the equation (6).
pm (t) = Em (t) × Save × A (6 ′)

And the difference (DELTA) P (T) of the total electric power generation until after the predetermined time T progresses when not performing maintenance and when performing maintenance is calculated by the following formula (9). This ΔP (T) corresponds to the area of the hatched portion 45 in FIG. The predetermined time T is predetermined and input to the photovoltaic power generation management device 16.

Next, ΔP (T) multiplied by the amount 1628 (amount m) per unit power generation obtained from the storage unit 162, and the number of maintenance [T / Δt] multiplied by the maintenance cost M per time. The difference m × ΔP (T) −M × [T / Δt] (10) shown in the following formula (10) is compared.
If Δt is determined so as to maximize the value, the optimal maintenance time can be calculated. [T / Δt] indicates a quotient obtained by dividing T by Δt.

(5. Effects of deterioration over time)
In addition to the accumulation of panel stains, there are also factors of deterioration over time as factors that cause a decrease in ideality that does not recover due to rain over time. The effect is not so large compared to that caused by dirt that does not fall due to rain, so it has not been considered above, but it is also possible to calculate the maintenance time based on this. In this case, with respect to a decrease in the ideality α _due to _{aging deterioration} , a reduction width Δα _{aging deterioration} per unit time of the ideality α is previously determined and stored in the storage unit 162 or the like.

In S14, an ideality αm (t) at a future time t in the case of performing maintenance on panel dirt that falls due to rain is calculated by the following equation (8 ′) similar to the equation (8).
αm (t) = α (t1) + gm (Δα, Δt, t, Δα _aging × t) (8 ′)

gm (Δα, Δt, t, Δα _{aged deterioration} × t) is a function indicating a change in the ideality α in the future in the case of performing maintenance on panel dirt that falls due to rain, as indicated by a dotted line 41 in the graph of FIG. 9 is a saw-shaped function similar to the dotted line 41 in FIG. 9, but the ideality α recovers to 1−Δα _{aged deterioration} × t for each Δt (that is, the decrease in the ideality due to the aged deterioration is not recovered). ) Is different.

  Subsequent processing is similar to the above, using the formulas (5 ″), (6 ′), and (9), the difference ΔP () in the total power generation amount after the predetermined time T elapses between when maintenance is not performed and when maintenance is performed. ΔP (T) corresponds to the area of the shaded portion 45 in Fig. 10. Then, Δt is determined so that the difference shown in the equation (10) is maximized. As M, a maintenance fee for panel dirt that does not fall due to rain, such as panel cleaning, may be determined in advance.

  The maintenance time for aging deterioration can be determined separately from the above, based on the specifications of the photovoltaic power generation panel 21, etc. In addition to this, for example, in S8, the status of the photovoltaic power generation panel 21 is further confirmed by the user in the rain. In step S14, if the panel dirt that does not fall due to rain does not occur, the ideality is reduced due to aging. The maintenance time can also be calculated as a thing. The maintenance time can be calculated in the same procedure as described in “4. As the maintenance cost M in Expression (10), a maintenance cost for aged deterioration such as parts replacement may be determined in advance.

  If it is input that panel dirt that does not fall due to rain has occurred, the processing described in “4. Calculation of maintenance time” may be performed. As the maintenance cost M of Expression (10), a maintenance cost for panel dirt that does not fall due to rain, such as panel cleaning, can be determined in advance and used.

  As described above, according to the present embodiment, the ideality of power generation efficiency is calculated, and the factors that lower the ideality (power generation amount) over time, such as the accumulation of panel dirt, are quantitatively evaluated from the transition. It is possible to manage solar power generation suitably, for example, by notifying the user of this and prompting appropriate measures. In particular, it is considered to be a useful function in a photovoltaic power generation system installed in a harsh environment such as an area where volcanic ash falls as dirt that does not fall even in the rain.

  Also, in this embodiment, it is determined whether or not the ideality has increased after the rain. As a cause of the decrease in the ideality, there is a slight accumulation of panel dirt that falls due to rain, and rain that requires high maintenance. It is possible to determine the accumulation of dirt that does not come off, and to notify the user, etc., so that appropriate measures can be taken.

  Furthermore, in this embodiment, since the predicted value of the future power generation amount is calculated using the change in the ideality, the future power generation amount can be grasped in consideration of the decrease in the ideality, the necessity of maintenance, etc. Management can be done efficiently.

  In addition, the difference between the predicted power generation amount calculated above and the predicted value of the future power generation amount when the ideality is restored by maintenance at a predetermined interval is obtained. Since the calculation is performed, it is possible to calculate the maintenance time for optimizing the cost effectiveness and to notify the user.

  In addition, when it is not determined that the ideality has decreased over time, it is determined whether the ideality is below a predetermined value for a certain period of time. It is possible to grasp the situation where the value is less than or equal to the value, and perform appropriate measures by notifying the user.

[Second Embodiment]
In the first embodiment, when it is determined that the decrease in ideality is due to dirt or the like that falls due to rain, the ideality is recovered by rain, so that the necessity for maintenance is low, and the optimal maintenance time is calculated. However, for example, in regions or seasons where there is extremely little rainfall, it is possible to calculate the optimum maintenance time and notify it in the same manner as in S14. Hereinafter, this example will be described as a second embodiment.

  In other words, in the second embodiment, in the same flow as in the first embodiment described with reference to FIG. 5 and the like, the degree of ideality decreases with time due to the cause of recovery due to rain, such as panel dirt that falls due to rain ( Also in S7), the maintenance time is calculated in S14.

In this case, as indicated by the solid line 41a in FIG. 11, the ideality α is restored at every rainfall interval Δtrain, and, as indicated by the dotted line 41, maintenance is performed at every maintenance time 43 that comes at the time interval Δt from the current time t1. Assuming that the ideality α is restored to the maximum value (for example, 1) even by performing the above, the ideality αm (t) at the future time t when maintenance is performed is calculated by the following equation (11).
αm (t) = α (t1) + gm (Δα, Δtrain, Δt, t) (11)

gm (Δα, Δtrain, Δt, t) is a function indicating a change in the ideality α in the future when maintenance is performed. Here, the calculation is performed in S12 in which the solid line 41a of the graph of FIG. This is a saw-like function that repeats the decrease in the ideality α at the slope Δα and the recovery of the ideality α for each Δt and Δt _rain . Here, it is assumed that the ideality α recovers to the maximum value (for example, 1), but the calculation is performed assuming that the recovery is performed only up to (1−Δα _aging × t) in consideration of the influence of aging degradation as described above. Is also possible.

  Subsequent processing is similar to the above, using the formulas (5 ″), (6 ′), and (9), the difference ΔP (T ΔP (T) corresponds to the area of the shaded portion 45 in Fig. 11. Then, Δt may be determined so that the difference shown in Expression (10) is maximized.

  As a result, in addition to the effects of the first embodiment, it is possible to calculate and notify the optimum maintenance time even when there is dirt or the like that drops due to rain.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these are naturally within the technical scope of the present invention. Understood.

1: Photovoltaic power generation management system 2: Photovoltaic power generation system 11: Electricity meter 12: Solar radiation meter 13: Thermometer 14: Rain gauge 15: Data logger 16: Photovoltaic power management device 21: Photovoltaic power generation panel

Claims (9)

A power generation efficiency calculation unit that calculates power generation efficiency using the amount of power generated by the solar power generation panel;
An ideality calculation unit that calculates an ideal value of power generation efficiency using the amount of solar radiation and the panel temperature of the photovoltaic power generation panel, and calculates a ratio between the power generation efficiency calculated by the power generation efficiency calculation unit and the ideal value as an ideality When,
A determination unit for determining whether or not the ideality has decreased over time;
A solar power generation management device characterized by comprising:   2. The sunlight according to claim 1, wherein the determination unit determines whether or not the ideality has increased after rainfall, using rainfall amount data indicating a temporal change in rainfall and the ideality. Power generation management device.   The photovoltaic power generation management device according to claim 1, further comprising a power generation amount prediction unit that calculates a predicted value of a future power generation amount using the change in the ideality.   Using the change in the ideality, calculate a predicted value of the future power generation amount when the ideality is restored by maintenance at a predetermined interval, obtain a difference from the predicted value calculated by the power generation amount prediction unit, The photovoltaic power generation management apparatus according to claim 3, further comprising a maintenance time calculation unit that calculates an optimum value of the maintenance time using the difference and the cost for one maintenance.   The said determination part determines whether the said ideality is below a predetermined value for a fixed time, when it is not determined with the said ideality falling with time. Item 5. The photovoltaic power generation management device according to any one of Items 4 to 6. An energy measuring device for measuring the amount of power generated by the photovoltaic panel;
A solar radiation measuring device for measuring solar radiation;
A temperature measuring device for measuring a panel temperature of the photovoltaic power generation panel;
A solar power management device,
Have
The photovoltaic power generation management device
A power generation efficiency calculation unit that calculates power generation efficiency using the electric energy;
An ideal value calculation unit that calculates an ideal value of power generation efficiency using the solar radiation amount and the panel temperature, and calculates a ratio between the power generation efficiency calculated by the power generation efficiency calculation unit and the ideal value as an ideal degree;
A determination unit for determining whether or not the ideality has decreased over time;
A photovoltaic power generation management system characterized by comprising: Computer
A power generation efficiency calculating step of calculating power generation efficiency using the amount of power generated by the solar power generation panel;
An ideality calculation step of calculating an ideal value of power generation efficiency using a solar radiation amount and a panel temperature of the photovoltaic power generation panel, and calculating a ratio between the power generation efficiency calculated in the power generation efficiency calculation step and the ideal value as an ideality When,
A determination step of determining whether or not the ideality has decreased over time;
A photovoltaic power generation management method characterized in that On the computer,
A power generation efficiency calculating step of calculating power generation efficiency using the amount of power generated by the solar power generation panel;
An ideality calculation step of calculating an ideal value of power generation efficiency using a solar radiation amount and a panel temperature of the photovoltaic power generation panel, and calculating a ratio between the power generation efficiency calculated in the power generation efficiency calculation step and the ideal value as an ideality When,
A determination step of determining whether or not the ideality has decreased over time;
A program for running On the computer,
A power generation efficiency calculating step of calculating power generation efficiency using the amount of power generated by the solar power generation panel;
An ideality calculation step of calculating an ideal value of power generation efficiency using a solar radiation amount and a panel temperature of the photovoltaic power generation panel, and calculating a ratio between the power generation efficiency calculated in the power generation efficiency calculation step and the ideal value as an ideality When,
A determination step of determining whether or not the ideality has decreased over time;
A recording medium on which a program for executing the program is recorded.

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