JP4999947B2 - Photovoltaic power generation output estimation method and solar power generation output estimation device - Google Patents

Description

  The present invention relates to a method and apparatus for estimating the output power of photovoltaic power generation.

  In the future, it is expected that home-use solar power generation will spread in earnest, and a large amount of solar power generation is expected to be connected to the power distribution system.

  By the way, since the output of photovoltaic power generation fluctuates depending on weather conditions, there is a concern that the output fluctuation greatly affects the voltage and frequency of the distribution system. Therefore, a method to mitigate the influence on the power distribution system by measuring the output of solar power generation and controlling the storage heat storage load, frequency control generator, and voltage regulator that match the output is being studied. .

  However, enormous costs are required to measure all the outputs of a large number of photovoltaic generators and to acquire the measurement data via a communication line. For example, the number of popular solar power generators in a certain power company is currently 40,000, and is scheduled to be 800,000 in 2020. Therefore, if the output measuring device of a solar power generator is 100,000 yen per unit, for example, it will currently cost 4 billion yen, and it will cost 80 billion yen in 2020.

  In order to solve this, Patent Document 1 discloses a power generation amount correlation model in which only the power generation amount of some solar power generators is measured and the power generation amounts of all other solar power generators are obtained from past data. A distribution system state estimation device that estimates using a power source has been proposed.

JP 2009-50064 A

In the apparatus of Patent Document 1, the correlation between the power generation amounts of two or more solar power generators is estimated based on past performance values, but this method has the following problems.
(1) When a photovoltaic generator is added, it is necessary to construct a new correlation model.
(2) Even when the solar power generator is stopped due to a failure or the like, power is generated according to the correlation model.

  This invention is made | formed in view of the said subject, The main objective is to estimate the output electric power of a solar power generator with low cost and high precision.

  In order to solve the above problems, the present invention provides a method (solar power generation output estimation method) for estimating the total output power of a solar power generator connected to an interconnection point on a distribution line by a computer, The computer acquires the load power supplied from the distribution line to the load connected to the interconnection point, and the physical quantity depending on the amount of solar radiation in the vicinity of the solar power generator, and refers to the acquired physical quantity And extracting the frequency of the fluctuation component synchronized with the fluctuation of the reference signal among the fluctuation components of the load power, and the amplitude of the frequency component at the extracted frequency of the frequency components of the load power, Of the frequency components of the reference signal, a step of calculating an amplitude ratio that is a ratio to the amplitude of the frequency component at the extracted frequency, and the calculated amplitude ratio to the reference signal The result of the calculation, and executes the steps of: estimating a total output power of the solar power generator.

  According to this method, in order to estimate the total output power of the solar power generator connected to the interconnection point based on the load power supplied from the distribution line and the physical quantity depending on the amount of solar radiation, two measurement data are obtained. Since it is used, the cost is low, and since real-time measurement data is used, the estimated output power is highly accurate.

  Moreover, this invention is a method (solar power generation output estimation method) which estimates the total output electric power of the solar power generator connected to the connection point on a distribution line with a computer, Comprising: The said computer is the said connection power. Acquiring load power supplied from the distribution line to a load connected to a point, acquiring a physical quantity depending on the amount of solar radiation in the vicinity of the solar power generator as a reference signal, and Fourier transforming the load power A step of creating a power spectrum of the load power, a step of Fourier transforming the reference signal to create a power spectrum of the reference signal, a power spectrum of the load power, and a power spectrum of the reference signal. Extracting the frequency at which the peaks coincide with each other as the peak frequency, and inverse Fourier transform of the power spectrum of the load power Determining the amplitude of the load power at the peak frequency; inverse Fourier transforming the power spectrum of the reference signal to determine the amplitude of the reference signal at the peak frequency; and the amplitude of the load power; A step of calculating an amplitude ratio that is a ratio to the amplitude of the reference signal, and a step of estimating a result of multiplying the reference signal by the calculated amplitude ratio as a total output power of the photovoltaic generator. It is characterized by doing.

  According to this method, in order to estimate the total output power of the solar power generator connected to the interconnection point based on the load power supplied from the distribution line and the physical quantity depending on the amount of solar radiation, two measurement data are obtained. Since it is used, the cost is low, and since real-time measurement data is used, the estimated output power is highly accurate.

In the solar power generation output estimation method of the present invention, the computer may calculate the amplitude ratio every predetermined time.
According to this method, since the amplitude ratio is updated as necessary to the latest state, the output power of the solar power generator can be estimated with higher accuracy.

  Moreover, in the said photovoltaic power generation output estimation method of this invention, the said computer uses the measured value of the illumination intensity sensor installed in the vicinity of the said photovoltaic power generator, or the output electric power value of the said 1 photovoltaic power generator as the said physical quantity. It is good also as acquiring.

In the solar power generation output estimation method of the present invention, the computer may extract a frequency at which a differential value of the power spectrum is 0 as the peak frequency.
According to this method, since the peak frequency can be specified with high accuracy, the output power of the solar power generator can be estimated with higher accuracy.

  The present invention includes a photovoltaic power generation output estimation device. In addition, the problems disclosed by the present application and the solutions thereof will be clarified by the description of the mode for carrying out the invention and the drawings.

  According to the present invention, it is possible to estimate the output power of a solar power generator with low cost and high accuracy.

1 is a diagram illustrating a configuration of a photovoltaic power generation output estimation system 1. FIG. It is a figure which shows the hardware constitutions of the photovoltaic power generation output estimation apparatus. It is a figure which shows the structure of the data memorize | stored in the memory | storage part 46 of the photovoltaic power generation output estimation apparatus 4, (a) shows the structure of measured value data 46A, (b) shows the structure of power spectrum data 46B, (C) shows the configuration of the amplitude data 46C. It is a flowchart which shows the process of the solar power generation output estimation apparatus 4. FIG. It is a graph which shows the process of the solar power generation output estimation apparatus 4, (a) shows the process of extracting the frequency Fp in which the peak of load electric power Pt and the reference signal P_ref corresponds, (b) is amplitude ratio a = PPt. The process of obtaining (Fp) / PP_ref (Fp) is shown, and (c) shows the process of obtaining the output power PV (t) by multiplying the reference signal P_ref (t) by the amplitude ratio a. It is a graph regarding a power spectrum, (a) shows the power spectrum after Fourier-transform, (b) shows the differential value of a power spectrum.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The photovoltaic power generation output estimation device according to the embodiment of the present invention measures a physical quantity that depends on the load power and the amount of solar radiation supplied from the pole transformer connected to the distribution line, and uses the physical quantity as a reference signal for the reference. The component of the load power synchronized with the fluctuation period of the signal is extracted, the amplitude ratio which is the ratio of the amplitude of the load power and the amplitude of the reference signal corresponding to the frequency of the component is calculated, and the amplitude ratio is calculated. The result obtained by multiplying the reference signal is estimated as the total output power of the solar power generator connected to the pole transformer.

  According to this, by measuring the physical quantity related to the load power and solar radiation amount by the pole transformer, the total output power of the photovoltaic generators under the pole transformer is estimated with low cost and high accuracy. be able to. Note that the load and the solar power generator are not necessarily limited to the pole transformer, and for example, the load and the solar power generator connected to one interconnection point on the distribution line may be targeted.

≪System configuration and overview≫
FIG. 1 is a diagram illustrating a configuration of a photovoltaic power generation output estimation system 1. The photovoltaic power generation output estimation system 1 includes a power distribution facility PS, a wattmeter 2, an illuminance sensor 3, and a photovoltaic power generation output estimation device 4. The distribution facility PS includes a substation P, a high voltage distribution line D1, a pole transformer Tr, a low voltage distribution line D2, solar power generators G1 and G2, and loads L1 and L2. The substation P transmits the voltage supplied from the power plant to the high-voltage distribution line D1 at 6600V. The high-voltage distribution line D1 supplies the voltage received from the substation P to a predetermined area. The pole transformer Tr is connected between the high-voltage distribution line D1 and the low-voltage distribution line D2, and reduces the voltage of 6600V received from the interconnection point CP on the high-voltage distribution line D1 to distribute the voltage of 100V to the low-voltage distribution line. Power is supplied to the electric wire D2. The low voltage distribution line D2 supplies the voltage received from the pole transformer Tr to the loads L1 and L2. The solar power generators G1 and G2 generate power from sunlight and supply the power to the low-voltage distribution line D2. The photovoltaic generators under the pole transformer Tr are collectively referred to as a photovoltaic generator G. The loads L1 and L2 consume power supplied from the pole transformer Tr and the solar power generators G1 and G2 through the low-voltage distribution line D2. Note that loads under the pole transformer Tr are collectively referred to as a load L.

  The wattmeter 2 is connected to the secondary terminal of the pole transformer Tr, measures the load power Pt under the pole transformer Tr, and notifies the photovoltaic power generation output estimation device 4 of the measured value data. The illuminance sensor 3 is installed in the vicinity of the solar power generator G, measures the amount of solar radiation P_ref, and notifies the solar power generation output estimation device 4 of the measured value data. The photovoltaic power generation output estimation device 4 acquires measured value data of the load power Pt and the solar radiation amount P_ref from the wattmeter 2 and the illuminance sensor 3, respectively, and based on the acquired measured values, the secondary side of the pole transformer Tr The total output power of the photovoltaic generator G connected to the following is estimated.

  FIG. 2 is a diagram illustrating a hardware configuration of the photovoltaic power generation output estimation device 4. The photovoltaic power generation output estimation device 4 includes a communication unit 41, a display unit 42, an input unit 43, a measurement value acquisition unit 44, a processing unit 45, and a storage unit 46, so that each unit can transmit and receive data via a bus 47. It is connected to the. The communication unit 41 is a part that performs IP (Internet Protocol) communication and the like with other devices via a network, and is realized by, for example, a NIC (Network Interface Card) or the like. The display unit 42 is a part that displays data in accordance with an instruction from the processing unit 45, and is realized by, for example, a liquid crystal display (LCD). The input unit 43 is a part where an operator inputs data, and is realized by, for example, a keyboard or a mouse. The measurement value acquisition unit 44 is connected to the wattmeter 2 and the illuminance sensor 3 via an interface cable such as RS-232C, acquires measurement value data from these measuring instruments, and delivers the acquired measurement value data to the processing unit 45. . The processing unit 45 exchanges data between each unit via a predetermined memory and controls the entire photovoltaic power generation output estimation device 4. A CPU (Central Processing Unit) stores the data in the predetermined memory. This is realized by executing the programmed program. The storage unit 46 stores data from the processing unit 45 and reads out the stored data. For example, the storage unit 46 is realized by a nonvolatile storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive). The Note that the photovoltaic power generation output estimation device 4 may be a stand-alone device (PC (Personal Computer) or the like), or a device (server or the like) that can communicate with a plurality of terminals via a network. May be.

<< Data structure >>
FIG. 3 is a diagram illustrating a configuration of data stored in the storage unit 46 of the photovoltaic power generation output estimation device 4. FIG. 3A shows the configuration of the measured value data 46A. The measured value data 46A is measured value data acquired from the measuring instrument related to the pole transformer Tr, and includes load power data 46A1 and reference signal data 46A2. The load power data 46A1 is measured value data of power consumed by the load L, obtained from the wattmeter 2 and supplied from the pole transformer Tr. From the total power consumed by the load L, the solar power generator G This corresponds to the differential power obtained by subtracting the output power. Therefore, the load power data 46A1 includes a component of output power from the solar power generator G. The reference signal data 46A2 is measured value data of the amount of solar radiation in the vicinity of the solar power generator G on the secondary side of the pole transformer Tr acquired from the illuminance sensor 3, and the output power of the solar power generator G is estimated. Used as a reference signal. That is, it is assumed that the component having the same frequency as the reference signal depending on the amount of solar radiation among the load power measured by the wattmeter 2 of the pole transformer Tr is the output power from the solar power generator G.

  FIG. 3B shows the configuration of the power spectrum data 46B. The power spectrum data 46B is data obtained by Fourier transforming the measurement value data 46A, and includes a load power power spectrum 46B1 and a reference signal power spectrum 46B2. The load power power spectrum 46B1 is data obtained by Fourier transforming the load power data 46A1. The reference signal power spectrum 46B2 is data obtained by Fourier transforming the reference signal data 46A2.

  FIG. 3C shows the configuration of the amplitude data 46C. The amplitude data 46C is data relating to the amplitude obtained in the process of estimating the output power of the solar power generator G. The peak load power amplitude 46C1, the peak reference signal amplitude 46C2, the amplitude ratio 46C3, and the output power data 46C4 are obtained. Including. The peak load power amplitude 46C1 is the amplitude of the load power at the peak frequency, and is obtained from data obtained by inverse Fourier transform of the load power power spectrum 46B1. The peak reference signal amplitude 46C2 is the amplitude of the reference signal at the peak frequency, and is obtained from data obtained by performing inverse Fourier transform on the reference signal power spectrum 46B2. The amplitude ratio 46C3 is a ratio between the peak load power amplitude 46C1 and the peak reference signal amplitude 46C2, and is calculated and updated every predetermined time. The output power data 46C4 is estimation data of the total output power of the solar power generator G under the pole transformer Tr, and is obtained by multiplying the reference signal data 46A2 by the amplitude ratio 46C3. The latest data is updated with the update.

  The storage unit 46 also stores calculation formula data for performing Fourier transform and inverse Fourier transform.

≪Device processing≫
FIG. 4 is a flowchart showing processing of the photovoltaic power generation output estimation device 4. In this process, the total output of the photovoltaic power generator G is obtained while the processing unit 45 mainly refers to and updates the data in the storage unit 46 in the photovoltaic power generation output estimation device 4 (hereinafter referred to as “output estimation device 4”). The power is estimated.

  First, the output estimation device 4 acquires the measurement value data of the load power Pt (t) on the secondary side of the pole transformer Tr from the power meter 2 by the measurement value acquisition unit 44, and the load power of the measurement value data 46A. The data 46A1 is stored in the storage unit 46 (S401). Next, the measurement value acquisition unit 44 acquires the measurement value data of the solar radiation amount P_ref (t) in the vicinity of the solar power generator G from the illuminance sensor 3, and stores it in the storage unit 46 as reference signal data 46A2 of the measurement value data 46A. (S402).

  Then, the output estimation device 4 causes the processing unit 45 to read the load power data 46A1 of the measurement value data 46A from the storage unit 46, and Fourier transform the load power data to create a power spectrum, and the power spectrum is converted into the power spectrum. It memorize | stores in the memory | storage part 46 as the load electric power spectrum 46B1 of the data 46B (S403). Next, the processing unit 45 reads the reference signal data 46A2 of the measurement value data 46A from the storage unit 46, Fourier transforms the reference signal data to create a power spectrum, and uses the power spectrum as a reference signal for the power spectrum data 46B. It memorize | stores in the memory | storage part 46 as power spectrum 46B2 (S404).

  Subsequently, the output estimation device 4 reads the load power power spectrum 46B1 and the reference signal power spectrum 46B2 of the power spectrum data 46B from the storage unit 46 by the processing unit 45, identifies the peak of each power spectrum, and the peak is The matching frequency (peak frequency) Fp is extracted (S405). A method for specifying the peak of the power spectrum will be described later.

  The graph of FIG. 5A shows a process of performing Fourier transform on the load power Pt (t) and the solar radiation reference signal P_ref (t) to extract a frequency Fp at which the peaks of the load power Pt and the reference signal P_ref match. .

  Then, the output estimating apparatus 4 performs inverse Fourier transform on the load power power spectrum 46B1 by the processing unit 45, and from the data indicating the amplitude PPt (f) of the load power, the amplitude PPt (Fp) of the load power with respect to the peak frequency Fp. Is stored in the storage unit 46 as the peak load power amplitude 46C1 of the amplitude data 46C (S406). Next, the processing unit 45 performs inverse Fourier transform on the reference signal power spectrum 46B2, obtains the amplitude PP_ref (Fp) of the reference signal with respect to the peak frequency Fp from the data indicating the amplitude PP_ref (f) of the reference signal, and outputs the amplitude data. The peak reference signal amplitude 46C2 of 46C is stored in the storage unit 46 (S407).

  Subsequently, the output estimation device 4 reads the peak load power amplitude 46C1 and the peak reference signal amplitude 46C2 of the amplitude data 46C from the storage unit 46 by the processing unit 45, and calculates the peak load power amplitude 46C1 and the peak reference signal amplitude 46C2. The ratio a is obtained, and the obtained ratio a is stored in the storage unit 46 as the amplitude ratio 46C3 of the amplitude data 46C (S408).

  The graph of FIG. 5B is obtained by performing inverse Fourier transform on the load power power spectrum and the reference signal power spectrum to obtain amplitudes PPt (f) and PP_ref (f) for each frequency, and amplitude PPt (Fp) at the peak frequency Fp. And PP_ref (Fp) are obtained, and the process of obtaining the amplitude ratio a = PPt (Fp) / PP_ref (Fp) is shown.

  Then, the output estimation device 4 reads out the reference signal data 46A2 of the measurement value data 46A from the storage unit 46 by the processing unit 45, and multiplies the reference signal P_ref (t) by the amplitude ratio a, whereby the pole transformer The output power PV (t) of the solar power generator G below the secondary side of Tr is estimated, and the estimated data is stored in the storage unit 46 as output power data 46C4 of the amplitude data 46C (S409).

  The graph in FIG. 5C shows a process of obtaining the output power PV (t) by multiplying the reference signal P_ref (t) by the amplitude ratio a.

  The above processing is performed every predetermined time, and the estimated value of the output power of the solar power generator G is accurately obtained by updating the amplitude ratio 46C3 and the output power data 46C4 of the storage unit 46 to the latest state as needed. Can be maintained. Note that the output power data 46C4 of the storage unit 46 is transmitted from the communication unit 41 to other devices on the network or displayed on the display unit 42, whereby the estimated value of the output power of the solar power generator G is related. You may make it notify a person.

≪Example of calculation method≫
In the process of S403 in FIG. 4, the load power on the secondary side of the pole transformer Tr is P _j (j = 0, 1, 2,..., N−1), the sampling period is Δt, and sampling is performed. The frequency is Δf (= 1 / nΔt), Fourier transform is performed, and a power spectrum is obtained. The same applies to S404.

The Fourier transform is according to Equation 1.

The power spectrum is obtained by Equation 2.

  Next, in the process of S406 in FIG. 4, Pj (k) at the frequency Fk (= kΔf) is calculated by inverse Fourier transform. The same applies to S407.

The inverse Fourier transform is according to Equation 3.

  Then, the maximum value of Pj (k) is obtained from the amplitudes (j = 0, 1, 2,..., N−1) of Pj (k) for each frequency.

  Subsequently, a method for obtaining a frequency at which the power spectrum after Fourier transform reaches a peak will be described below. FIG. 6A is a graph showing a power spectrum after Fourier transform.

First, the power spectrum smoothing process of Formula 2 is performed. Specifically, as shown in Equation 4, m averages are taken.

Next, as shown in Equation 5, the power spectrum is differentiated.

  FIG. 6B is a graph showing the differential value of the power spectrum. In this graph, a portion (frequency range) where the absolute value of the differential value of the power spectrum has a threshold value h or more is extracted. Of the extracted locations, the frequency Fp at which the differential value = 0 between the location where the differential value is positive (F1) and the location where the subsequent negative value (F2) is 0 is set as the peak position. This is because the power spectrum is not determined to be a peak simply because the differential value = 0, but rises with a positive slope greater than or equal to a predetermined value and reaches a peak (differential value = 0), and then reaches a peak below the predetermined value. By extracting a part that descends with a negative slope, the peak frequency at that part is accurately identified.

  In the above embodiment, the program executed by the processing unit 45 is recorded on a computer-readable recording medium so that each unit in the photovoltaic power generation output estimating apparatus 4 shown in FIG. The photovoltaic power generation output estimation device 4 according to the embodiment of the present invention is realized by causing the computer to read and execute the program. In this case, the program may be provided to the computer via a network such as the Internet, or a semiconductor chip or the like in which the program is written may be incorporated in the computer.

  According to the embodiment of the present invention described above, the wattmeter 2 can be used without measuring the data of the total output power of each solar power generator G (G1, G2) on the secondary side of the pole transformer Tr. The total output power of the photovoltaic generator G is estimated based on the load power on the secondary side of the pole transformer Tr and the measured value of the amount of solar radiation by the illuminance sensor 3, so that the cost required for the measuring instrument and communication line Can be reduced. Even if the wattmeter 2 and the illuminance sensor 3 are not attached to the individual solar power generators G, they may be installed one by one for each pole transformer Tr. Next, the total output power of the solar power generator G can be estimated with high accuracy by acquiring real-time measurement values as needed.

  Further, even when the photovoltaic generator G is added on the secondary side of the pole transformer Tr, the total output power of the photovoltaic generator G can be estimated without constructing a new correlation model. When there is a solar power generator G that is stopped due to a failure or the like, the load power measured by the wattmeter 2 changes. Can be reflected. According to the above, it is possible to accurately estimate the total output power of the solar power generator G regardless of the number of solar power generators G and the operating state under the pole transformer Tr.

<< Other embodiments >>
As mentioned above, although the form for implementing this invention was demonstrated, the said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and equivalents thereof are also included in the present invention. For example, the following embodiments can be considered.
(1) In the above embodiment, the measured value of the illuminance sensor 4 is used as the physical quantity depending on the amount of solar radiation. However, the measured value of the output power of one solar power generator G under the pole transformer Tr is used. May be used.
(2) Even if a plurality of peak frequencies are extracted in the process of S405 in FIG. 4, the amplitude ratios required in the process of S405 are equal in principle. However, when a plurality of amplitude ratios are obtained from a plurality of peak frequencies, measures such as taking an average value of the amplitude ratios or discarding a value deviating from a predetermined range due to a standard deviation or the like may be performed.

DESCRIPTION OF SYMBOLS 1 Solar power generation output estimation system 2 Wattmeter 3 Illuminance sensor 4 Solar power generation output estimation apparatus (computer)
44 Measurement Value Acquisition Unit 45 Processing Unit 46 Storage Unit 46A Measurement Value Data 46A1 Load Power Data 46A2 Reference Signal Data 46B Power Spectrum Data 46B1 Load Power Power Spectrum 46B2 Reference Signal Power Spectrum 46C Amplitude Data 46C1 Peak Load Power Amplitude 46C2 Peak Reference Signal Amplitude 46C3 Amplitude ratio 46C4 Output power data D1 High voltage distribution line (distribution line)
D2 Low voltage distribution line G, G1, G2 Photovoltaic generator L, L1, L2 Load Tr Pillar transformer (interconnection point)

Claims (10)

A method for estimating the total output power of a photovoltaic generator connected to an interconnection point on a distribution line by a computer,
The computer
Obtaining a load power supplied from the distribution line to a load connected to the interconnection point and a physical quantity depending on an amount of solar radiation near the solar power generator;
Using the acquired physical quantity as a reference signal, and extracting the frequency of the fluctuation component synchronized with the fluctuation of the reference signal among the fluctuation components of the load power;
Calculating an amplitude ratio that is a ratio of an amplitude of the frequency component at the extracted frequency among the frequency components of the load power and an amplitude of the frequency component at the extracted frequency among the frequency components of the reference signal; ,
Estimating the result of multiplying the calculated amplitude ratio by the reference signal as the total output power of the photovoltaic generator;
The photovoltaic power generation output estimation method characterized by performing. A method for estimating the total output power of a photovoltaic generator connected to an interconnection point on a distribution line by a computer,
The computer
Obtaining load power supplied from the distribution line to a load connected to the interconnection point;
Obtaining a physical quantity depending on the amount of solar radiation near the solar generator as a reference signal;
Fourier transforming the load power to create a power spectrum of the load power;
Fourier transforming the reference signal to create a power spectrum of the reference signal;
Extracting, as a peak frequency, a frequency at which peaks coincide between the power spectrum of the load power and the power spectrum of the reference signal;
Performing an inverse Fourier transform on the power spectrum of the load power to obtain an amplitude of the load power at the peak frequency;
Performing an inverse Fourier transform on the power spectrum of the reference signal to obtain an amplitude of the reference signal at the peak frequency;
Calculating an amplitude ratio that is a ratio of the amplitude of the load power and the amplitude of the reference signal;
Estimating the result of multiplying the calculated amplitude ratio by the reference signal as the total output power of the photovoltaic generator;
The photovoltaic power generation output estimation method characterized by performing. It is the photovoltaic power generation output estimation method according to claim 1 or 2,
The computer
The amplitude ratio is calculated every predetermined time.
A photovoltaic power generation output estimation method characterized by the above. It is the photovoltaic power generation output estimation method according to claim 1 or 2,
The computer
As the physical quantity, a measurement value of an illuminance sensor installed in the vicinity of the solar power generator or an output power value of the solar power generator of 1 is acquired. It is a photovoltaic power generation output estimation method according to claim 2,
The computer
A frequency at which the differential value of the power spectrum is 0 is extracted as the peak frequency. A device for estimating the total output power of a photovoltaic generator connected to a connection point on a distribution line,
Means for obtaining a load power supplied from the distribution line to a load connected to the interconnection point, and a physical quantity depending on an amount of solar radiation in the vicinity of the solar power generator;
Means for extracting the frequency of the fluctuation component synchronized with the fluctuation of the reference signal among the fluctuation components of the load power, using the acquired physical quantity as a reference signal;
Means for calculating an amplitude ratio that is a ratio of an amplitude of the frequency component at the extracted frequency among the frequency components of the load power and an amplitude of the frequency component at the extracted frequency among the frequency components of the reference signal; ,
Means for multiplying the reference signal by the calculated amplitude ratio as a total output power of the photovoltaic generator;
A photovoltaic power generation output estimation device comprising: A device for estimating the total output power of a photovoltaic generator connected to a connection point on a distribution line,
Means for obtaining load power supplied from the distribution line to a load connected to the interconnection point;
Means for obtaining a physical quantity depending on the amount of solar radiation in the vicinity of the solar generator as a reference signal;
Means for Fourier transforming the load power to create a power spectrum of the load power;
Means for Fourier transforming the reference signal to create a power spectrum of the reference signal;
Means for extracting, as a peak frequency, a frequency at which peaks coincide between the power spectrum of the load power and the power spectrum of the reference signal;
Means for inverse Fourier transforming the power spectrum of the load power to determine the amplitude of the load power at the peak frequency;
Means for inverse Fourier transforming the power spectrum of the reference signal to determine the amplitude of the reference signal at the peak frequency;
Means for calculating an amplitude ratio that is a ratio of the amplitude of the load power and the amplitude of the reference signal;
Means for multiplying the reference signal by the calculated amplitude ratio as a total output power of the photovoltaic generator;
A photovoltaic power generation output estimation device comprising: It is a photovoltaic power generation output estimating device according to claim 6 or 7,
The amplitude ratio is calculated every predetermined time.
A photovoltaic power generation output estimation device characterized by that. It is a photovoltaic power generation output estimating device according to claim 6 or 7,
As the physical quantity, a measured value of an illuminance sensor installed near the solar power generator or an output power value of the solar power generator of 1 is acquired. It is a photovoltaic power generation output estimation device according to claim 7,
A frequency at which a differential value of the power spectrum is 0 is extracted as the peak frequency.