JP2005051048A - Method of evaluating amount of power generated by field photovoltaic power generating system, computer-readable recording medium recording evaluation program, and evaluation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of forming an I-V curve which is high in accuracy and general-purpose properties, and to provide a method of evaluating the amount of power generated by a field photovoltaic power generating system by the use of the above I-V curve. <P>SOLUTION: Two methods (one is a monthly temperature coefficient method and the other is a temperature-corrected system output coefficient method) for calculating efficiency obtained by adding a loss caused by a temperature rise to a system output coefficient are developed, and it is made clear that the calculation results obtained through the two methods are very similar to each other. It is found that both methods become more effective when a method of forming an I-V curve through a theoretical formula is employed as a method of forming an I-V curve at an optional insolation intensity and a solar cell temperature. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

As shown in FIG. 3, a solar cell directly converts solar light energy into electric energy. In other words, the photovoltaic effect, which is a type of photoelectric effect, is applied to generate an electromotive force. When light (photons) with appropriate energy enters a solar cell, free electrons and holes are generated. To do. In the solar cell, electrons and holes that reach the vicinity of the pn junction in the semiconductor diffuse to the n-type semiconductor side and the p-type semiconductor side, respectively, and gather at both electrode parts, so that power can be taken out and voltage and current are generated. That is why.
Solar cells can be broadly classified into crystalline silicon, amorphous silicon, and compound. Crystalline silicon solar cells, particularly single crystal solar cells, have a complicated manufacturing process and require a large amount of electric power for manufacturing. Recently, there have been reports that conversion efficiency exceeding 20% has been achieved by devising device structures. In a polycrystalline silicon solar cell with a slightly simpler manufacturing process, the solar cell conversion efficiency is practically about 10% to 15%. An amorphous silicon solar cell (amorphous solar cell) is promising as a low-cost solar cell because the manufacturing process is simple, the manufacturing energy is small, and the silicon material is small. Furthermore, since it can be formed on various substrates with a thin film, a wide range of applications is expected. The efficiency is about 10% in practical use.
In the power generation system (photovoltaic power generation system) using such a solar cell, the present invention provides a measurement value or a specification value (respectively, a solar cell power generation output and a power generation amount of the solar power generation system installed in the field). A method for accurately and accurately evaluating the extent of the comparison with the factory test value of the solar cell or the rated value of the solar cell of that type), and a computer-readable record recording the program The present invention relates to a medium and an evaluation apparatus / system thereof.

In recent years, solar power generation systems have been widely spread due to reductions in solar cells and their system prices, the establishment of a power company acceptance system for reverse power flow, and government subsidies. New high-performance solar cells have also been developed. Recently, however, we frequently hear questions from solar power generation system installers and installers that the power generation output and power generation amount of the solar cells actually installed are not as high as the original specifications. Even when the present inventors actually investigated the output / power generation amount of the solar cell, there are many cases where the output / power generation amount is considerably small.
In field tests conducted by countries, etc., “system output coefficient” is often used. “System output coefficient” means [amount of power generated by a photovoltaic power generation system during a certain period (KWH)] [amount of solar radiation irradiated to that system during the same period (KWH / m ² ) * solar cell at the standard solar radiation intensity Rated output (KW / KW / m ² )]. In addition, as a conventionally practiced method, the “solar cell conversion efficiency” obtained by dividing the power generation amount for a certain period by the solar cell area multiplied by the solar cell light-receiving surface measured by the pyranometer measured during the same period. There is also a method of seeking and evaluating. Further, instead of evaluating with an integrated value for a certain period, evaluation is performed by dividing a measured solar cell output at each time point by an output value roughly obtained from solar radiation intensity and solar cell temperature. However, these methods literally evaluate the approximate value, and it takes a long period of time for evaluation or an accurate evaluation value cannot be obtained. In addition, since these technologies have low evaluation accuracy, it is difficult to elucidate the cause and implement countermeasures even when power and power generation are insufficient.

Therefore, recently, “(solar cell) IV curve measuring device” has been developed and marketed. In this device, the solar cell to be evaluated is disconnected from the connected inverter, load, etc., connected to a simulated load (capacitor load, electronic load, etc.), and the load value is automatically switched and changed at high speed. By measuring the generated voltage (V) -generated current (I) value of about 40-50 sets within about 0.5 seconds, a voltage-current curve (IV curve) is obtained, and at the same time, the temperature of the solar cell (hereinafter referred to as solar The battery temperature or module temperature) and the solar radiation intensity of the solar cell light receiving surface are obtained, and these values are used to return to the IV curve of the standard state, and compared with the manufacturer's specifications, the output of the solar cell is evaluated. is there. In other words, the method for evaluating this device is to convert the IV curve measured at the solar radiation intensity and solar cell temperature at the time to be evaluated into the IV curve of the standard condition (solar radiation intensity 1 kW / m ² , solar cell temperature 25 ° C). Conversion values used by solar cell manufacturers (reference circuit short circuit current (Isc), open circuit voltage (Voc), optimum voltage (Vop), optimum current (Iop), etc.)), actual maximum output power Pmax ( Iop * Vop) to compare and evaluate. Then, the output (electric power) of the solar cell to be evaluated and the evaluation result are output by a personal computer / microcomputer.
Despite the fact that this “IV curve measuring instrument” occupies an important position in the evaluation of the output and power generation amount of solar cells, there are surprisingly few models on the market in Japan and overseas. The hardware principle and evaluation software of the model are similar. In general, the problems of the evaluation method and apparatus using the “IV curve measuring device” are as follows.
(1) The core part of the evaluation software of this equipment is the solar radiation intensity at the time of measurement, the generated voltage V-generated current I value (IV curve value) at the solar cell temperature, the reference state (solar radiation intensity 1 kW / m ² , This is a method (conversion formula) for converting (converting) into a voltage-current value (IV curve value) at a module temperature of 25 ° C. The conversion formula used in the past (the formula in the left or middle column of the table in FIG. 5) is the condition (range) of the solar radiation intensity to which the conversion formula can be applied, and the solar radiation is about 0.8 kW / m ² or more. It is limited to cases where it is stable, and there are many cases of solar radiation intensity conditions that cannot actually be evaluated. That is, a general-purpose high-accuracy conversion formula has not generally been established.
(2) Besides the evaluation of the output at each time of the solar cell and the photovoltaic power generation system, a method for accurately evaluating the power generation amount for a certain period, that is, KWh has not been established.
(3) In general, the fluctuation of solar radiation is severe, and the solar radiation intensity can be seen to change from highest to lowest within 0.5 seconds. Therefore, a technique for measuring the voltage-current value (IV curve) at a higher speed is necessary, and the conventional technique is not sufficient in this respect.
(4) When evaluating the solar cell output, it is desirable to measure and evaluate the output / power generation amount of the solar cell without disconnecting the solar cell in operation from the connected solar cells.

  In consideration of the above facts in the present invention, the power generation amount evaluation of the solar power generation system can be measured without disconnecting the solar cell from the solar power generation system, and a method that can evaluate the power generation amount is mainly considered. Here, the “IV curve measuring device” is not used. That is, it is set as the method evaluated in a connection state. That is, an actual solar power generation system is always in an operating state, and it is difficult to stop and disconnect from the system to evaluate the output and power generation amount. Therefore, an evaluation method that can be carried out without using an “IV curve measuring device” is desired. In general, as described above, as a method of evaluating a photovoltaic power generation system in a connected state, the output of the system at a certain time (power generation) and the output calculated from the solar radiation intensity at that time and the solar cell temperature (power generation) It is fundamental to find and evaluate the ratio. To that end, the following main technologies are required, but none of them has been established yet.

Technology for creating an IV curve at an arbitrary solar radiation intensity and solar cell temperature from solar cell characteristic values If such an IV curve is drawn, calculation output (power generation) can be accurately calculated, and basically solar power generation Accurate evaluation of system power generation is possible.

(2) It is necessary to be able to perform a stable evaluation even under intense solar radiation fluctuations, and a technology capable of performing a stable evaluation that is not easily affected by the intensity of solar radiation intensity or solar cell temperature.

(3) Others It is also necessary to have a technique that can be evaluated by measuring in the shortest possible time and whether the photovoltaic power generation system is capable of MPPT operation.

Here, in order to fully understand the conventional technology and problems related to evaluation, the basic technology of the solar cell will be described, and the characteristics and characteristic curves of the solar cell and the evaluation method will be described.
FIG. 5 shows a voltage-current curve (IV curve), which is an output characteristic curve of the solar cell, in which the horizontal axis indicates the voltage V and the vertical axis indicates the current I. Moreover, the broken line has shown the voltage-power curve (PV curve), the horizontal axis is the voltage V, and a vertical axis | shaft is the electric power P (V * I).
The output power of the solar cell is the product of the voltage V and the current I, and the point at which the output of the solar cell is maximum is called the maximum output point (Pmax). The values of current I and voltage V at maximum output point Pmax are called optimum current Iop and optimum voltage Vop. The voltage V when the current is zero is called the release voltage Voc, and the current I when the voltage is zero is called the short-circuit current Isc.
The IV curve, which is the curve of the generated voltage and generated current, differs depending on the difference in individual characteristics of the solar cell, and the solar radiation intensity of the received light and the solar cell temperature. Therefore, the characteristic values of the solar cell are the short-circuit current Isc, the optimum current Iop, the optimum voltage Vop, and the open-circuit voltage at the reference solar cell temperature (25 ° C) at the reference solar radiation intensity (1 kW / m ² ) (referred to as “reference state”). Voc, solar cell series resistance Rs, fluctuation value α (A / ° C) of short-circuit current Isc when temperature changes by 1 ° C, fluctuation value β (V / ° C) of open-circuit voltage Voc when temperature changes by 1 ° C , Indicated by a curve correction factor K. The characteristic values of solar cells are indicated by short-circuit current Isc, optimum current Iop, optimum voltage Vop, open circuit voltage Voc, etc., when solar radiation is 1 kW / m ² and the solar cell is 55 ° C. (also referred to as “operating state”). Sometimes.
Further, as described above, the output characteristic value of the solar cell is generally given by the manufacturer in a state where the solar radiation intensity is 1 kW / m ² and the solar cell temperature is 25 ° C. (may include 55 ° C. in some cases). For this reason, when the solar cell temperature is other than 25 ° C or 55 ° C, or when the solar radiation intensity is other than 1 kW / m ² , the output or power generation amount of the solar cell to be evaluated is the original output or power generation amount of the solar cell. I don't know how much it compares. In other words, when the solar cell temperature is a value different from the reference temperature, for example 38 ° C., and the solar radiation intensity is different from the standard solar radiation intensity, for example 700 W / m ² , the IV curve data represents the solar radiation intensity in the standard state. Unless it can be converted to 700 W / m ² and a solar cell temperature of 38 ° C., it is not known how much the output of the solar cell to be evaluated is. As described above, in the evaluation of the output / power generation amount of the solar cell, the formula for converting the IV curve in the reference state into the arbitrary solar radiation intensity, the IV curve of the arbitrary solar cell temperature, or the arbitrary solar radiation intensity, the arbitrary solar cell temperature. The formula to accurately convert the IV curve measured in step 1 into the IV curve of the standard condition (insolation intensity 1kW / m ² , solar cell temperature 25 ° C) is indispensable. As described above, under the condition where the solar radiation intensity is extremely limited (when stable at about 800 to 850 W / m ² or more), the formula for returning to the IV curve data in the standard state is conventionally shown in JIS C 8913 etc. The conversion formulas used are generally applied (the conversion formulas in the left column or middle column of the table in FIG. 4. These formulas are also shown in the IEA, and are also applied to “IV measuring instruments” made in the United States. However, in this way, the conversion formula that can be applied under very limited conditions of solar radiation intensity and has a problem with accuracy is not substantially useful for solar cell output evaluation. In addition, there is a problem whether α, β, Rs, and K, which are characteristic values in the reference state, can be used in the equation as they are under various solar radiation intensity and solar cell temperature conditions when applying this conversion equation.

There was also a method of drawing the IV curve of the reference state from the characteristic values Isc, Iop, Vop, Voc, etc. of the reference state, which is necessary for the evaluation of the amount of generated power (Fig. 7). The curve creation method has not been sufficiently established for its application and application.
Furthermore, the series resistance Rs, which is a characteristic value of the solar cell, is greatly influenced by the solar cell temperature, and thus an expression expressed as a function of the solar cell temperature is known. For example, the Japan Quality Assurance Organization
Rs = {1 + 3.3717 * 10-3 (T−298) + 9.7058 * 10−5 (T−298) ² } * Rs ′
It is proposed that the value of the series resistance Rs at the solar cell temperature T (absolute temperature) is estimated from the series resistance value Rs ′ at the solar cell temperature of 25 ° C. (absolute temperature 298 K). However, this equation is an empirical equation measured using a limited solar cell and is not a general-purpose equation, and is only a partial solution.

In the above-mentioned “conventional technology”, general problems as well as the current state of the technology have been described, but here, the problems to be solved by the present invention will be mainly described.
The first is to convert the solar cell voltage-current curve (IV curve) at the solar radiation intensity and solar cell temperature measured as described above into the standard state (solar radiation intensity 1 kW / m ² , solar cell temperature 25 ° C.). The problem is that an accurate and general-purpose conversion formula for comparative evaluation has not yet been established. Conversely, the voltage-current curve (IV curve) at the solar radiation temperature and solar cell temperature at the time of measurement is accurately determined from the characteristic values (Isc, Iop, Vop, Voc, α, β, Rs, K) in the reference state. Moreover, a general formula has not been established.
As a specific example, a conversion formula that converts an IV curve of any solar radiation intensity / solar cell temperature condition that is generally used today into an IV curve of the reference state (the conversion formula in the left or center column of the table in FIG. 4) ) Has a disadvantage that the calculation accuracy is poor when the solar radiation intensity is about 800 to 850 W / m ² or less as described above. For this reason, the subject that the actually measured IV curve cannot be converted into the IV curve in the standard state is pointed out unless the solar radiation intensity at the time of measurement is greater than about 800 to 850 W / m ² . In other words, in the evaluation using the “IV curve measuring device”, the IV and PV curves obtained from the measured IV and PV curves and the basic characteristics of the solar cells under the measured solar radiation intensity and solar cell temperature conditions are sufficient under the measurement conditions. It was not possible to compare and evaluate with high accuracy. In order to solve this problem, the present invention proposes a method for creating an IV curve with high accuracy and versatility, and an evaluation method using the method.

Second, a method for drawing an IV curve in a reference state from characteristic values (Isc, Iop, Vop, Voc, etc.) in the reference state has not been sufficiently established. For this reason, the IV curve of solar radiation intensity during measurement and solar cell temperature conditions could not be drawn accurately and universally, so the output of the actually installed solar battery and the power generation amount that is the integrated value were accurately and universally used. Could not be evaluated. In addition, since the method has not been well established, the simulation calculation of the annual power generation of the solar power generation system could not be performed accurately, and it was difficult to fully implement the design and operation of the solar power generation system. There was also a movement to search for a more theoretical method instead of the equation shown in the lower column of FIG. For example, a solar cell basic equation is used as a conversion formula, and the basic characteristic values (Io, Rs, Rsh, etc.) are expressed as functions using solar radiation intensity and solar cell temperature, and this value is applied to the basic characteristic equation and solved. This is a method for obtaining a curve. In this method, the series resistance Rs, the parallel resistance Rsh, etc., which are the characteristic values of the solar cell, are greatly affected by the solar cell temperature, so these values are expressed as a function of the solar cell temperature, but Rs, Rsh, etc. As described above, this is a value obtained by measurement under limited conditions using a specific type of solar cell or the like. For this reason, it is difficult to say that the method is general-purpose and accurate, and there is a problem with the calculation results obtained using these values.
Another theoretical method is to solve the basic formula of the solar cell as a nonlinear equation (The Institute of Electrical Engineers of Japan 1 (Iga: “Method of creating an IV curve using the voltage-current characteristics of a solar cell in the light irradiation state and its application) ”Electronics, Vol. 116, No. 10, 1996)), but the method of drawing the IV curve of the reference state from the aforementioned solar cell characteristic values (Isc, Iop, Vop, Voc), other than the reference state There are still problems with the IV curve creation method of conditions (solar cell temperature 40 ° C, 55 ° C, etc.), how to obtain Rs, and the method of curve interpolation of basic characteristic values (IL, Co, n, Rsh, Rs, etc.). It was.

What are the issues (e.g., Pmax operation evaluation method, operation voltage evaluation method) and how to solve them in order to enable stable and accurate evaluation of the photovoltaic power generation system while being connected to the grid? There was a problem of kika.

  Even under conditions such as severe fluctuations in solar radiation, there was a problem of how to make a stable and accurate evaluation.

Also, it was not clear what kind of solar radiation conditions and solar cell temperature conditions could be used for stable evaluation.

  In order to improve the efficiency of the photovoltaic power generation system, there was also a problem of how to apply the evaluation method to sort and elucidate various losses.

The method for evaluating the power generation amount of the solar power generation system according to claim 1 is:
Monthly system output coefficient (%) of the target solar power generation system (= (Monthly measured system power generation amount (KWh)) / (Monthly light receiving surface solar radiation amount (KWh / m ² )) / Solar cell rated capacity (KW / KW) / m ² ) * 100)
And in order to calculate the loss (%) due to the temperature rise of the solar cell (= (100−monthly temperature coefficient)), the monthly temperature coefficient (%) (= (monthly calculation system power generation amount (KWh)) / month light receiving surface Solar power I of any solar radiation intensity / solar cell temperature required for calculating the amount of solar power generation required for calculating solar radiation (KWh / m ² ) / solar cell rated capacity (KW / KW / m ² ) * 100) As a method for creating a -V curve, (1) a method for converting an IV curve of a standard solar cell ("practical IV curve creation method") or (2) a method for solving a solar cell basic formula (" Using the theoretical formula “IV curve creation method”), calculate the loss (%) due to temperature rise,
The power generation amount of the photovoltaic power generation system is evaluated based on a value obtained by adding the loss due to the temperature increase to the system output coefficient.

The method for evaluating the power generation amount of the solar power generation system according to claim 2 is:
Monthly system output coefficient (%) of the target solar power generation system (= (Monthly measured system power generation amount (KWh)) / (Monthly light receiving surface solar radiation amount (KWh / m ² )) / Solar cell rated capacity (KW / KW) / m ² ) * 100)
And the amount of power generation of the photovoltaic power generation system is evaluated by a value obtained by adding a loss (%) due to a temperature rise of the solar cell (= (100-monthly temperature coefficient)) to the system output coefficient. Yes,
Monthly temperature coefficient (%) (= (Monthly calculation system power generation (KWh)) / Monthly light receiving surface solar radiation (KWh / m ² ) / Solar cell rated capacity (KW / KW / m ² ) * 100) Necessary for calculation In the process of calculating the monthly calculation system power generation amount, in the creation of an IV curve for calculating the power generation amount of any solar radiation intensity and solar cell temperature,
{01} Voltage V, current I, photovoltaic current IL at a solar radiation intensity of 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{02} A function obtained by differentiating the function Func (V, I, IL, Co, n, Rsh, Rs, T) with a variable V: Div (V, I, IL, Co, n, Rsh, Rs, T) make,
{03} Specification values for solar cells (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )), short circuit current Isca, optimum current Iopa, optimum voltage Vopa, open circuit Select point P1 (0, Isca), P2 (Vopa, Iopa), P3 (Voca, 0) of voltage Voca,
{04} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 where T is the reference state temperature Ta (298 K), the series resistance Rs is the specification value Rsa at the reference temperature, and Substituting the values of the points of P1, P2, P3 and IL, Co, n, Rsh as unknowns: Func (0, Isca, IL, Co, n, Rsh, Rsa, Ta) = 0,
Relational expression: Func (Voca, 0, IL, Co, n, Rsh, Rsa, Ta) = 0,
Formula: Func (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0
{05} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value Rsa and the value of the point P2 (Vopa , Iopa) and IL, Co, n, Rsh as unknowns,
Create the relation: Div (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0, then
{06} The four relational expressions: Func (0, Isca, IL, Co, n, Rsh, Rsa, Ta) = 0, Func (Voca, 0, IL, Co, n, Rsh, Rsa, Ta) = 0 , Func (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0, Div (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0 satisfying solution A (ILa, Coa , na, Rsha) is calculated by a nonlinear solution program, then
{07} Similar to the standard state of the solar cell, the short-circuit current Iscb is the specification value at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) , Select points P1 (0, Iscb), P2 (Vopb, Iopb), P3 (Vocb, 0) of the optimal current Iopb, optimal voltage Vopb, open circuit voltage Vocb,
{08} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0, the second temperature Tb (313K) at T, the series resistance Rs, the specification value Rsb at the temperature, and Substituting the values of the points P1, P2, and P3 of {07}, IL, Co, n, and Rsh are unknown relations: Func (0, Iscb, IL, Co, n, Rsh, Rsb, Tb) = 0,
Relational expression: Func (Vocb, 0, IL, Co, n, Rsh, Rsb, Tb) = 0
Formula: Func (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0
{09} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the series resistance Rs of the second temperature Tb (313K) is set to the value Rsb at the second temperature and the above Substituting the value (Vopb, Iopb) at point P2 of {07}, and making IL, Co, n, and Rsh unknown
Create the relation: Div (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0, then
{10} The four relational expressions: Func (0, Iscb, IL, Co, n, Rsh, Rsb, Tb) = 0, Func (Vocb, 0, IL, Co, n, Rsh, Rsb, Tb) = 0 , Func (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0, Div (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0 satisfying solution A (Ilb, Cob , nb, Rshb) by a non-linear solution program, then
{11} The short circuit current Iscc, which is the specification value at the third solar cell module temperature Tc (328 K (tc = 55 ° C)) and solar radiation intensity Ec (1 kW / m ² )) as in the standard state of the solar cell Select points P1 (0, Iscc), P2 (Vopc, Iopc), P3 (Vocc, 0) for the optimal current Iopc, optimal voltage Vopc, and open-circuit voltage Vocc,
{12} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0, the third temperature Tc (328 K) at T, the series resistance Rs, the specification value Rsc at the temperature, and Substituting the values of the points P1, P2, and P3 of {11}, IL, Co, n, and Rsh are unknowns: Func (0, Iscc, IL, Co, n, Rsh, Rsc, Tc) = 0,
Relational expression: Func (Vocc, 0, IL, Co, n, Rsh, Rsc, Tc) = 0
Create a relational expression: Func (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0
{13} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value Rsc at the third temperature and the series resistance Rs of the third temperature Tc (328 K) and Substituting the value (Vopc, Iopc) of the point P2 of {11} and making IL, Co, n, Rsh unknown
Create the relation: Div (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0, then
{14} The above four relational expressions: Func (0, Iscc, IL, Co, n, Rsh, Rsc, Tc) = 0, Func (Vocc, 0, IL, Co, n, Rsh, Rsc, Tc) = 0 , Func (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0, Div (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0 satisfying solution A (Ilc, Coc , nc, Rshc) by a non-linear solution program, then
{15} Measured value of solar cell to be evaluated Solar radiation intensity Ej, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273), and values of generated voltage Vj−generated current Ij under these conditions,
{16} Solution A (ILa, Coa, na, Rsha) of {06} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) in the reference state, the temperature tb ( Celsius: Tb = tb + 273) {10} solution B (ILb, Cob, nb, Rshb), temperature tc (Celsius: Tc = tc + 273), {14} solution C (ILc, Coc, nc, Rshc) ) And curve interpolation at three points for each of the input values Rsa, Rsb, Rsa, Rsc (IL, Co, n, Rsh, Rs), and the characteristic value M at the measured temperature tj (Celsius: Tj = tj + 273) (ILm, Com, nm, Rshm, Rsm) is calculated, then
After correcting {17} ILm with IL'm = Ilm * Ej / Ea by the measured solar radiation intensity Ej, the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. It is characterized by.

The method for evaluating the power generation amount of the solar power generation system according to claim 3 is:
Monthly system output coefficient (%) of the target solar power generation system (= (Monthly measured system power generation amount (KWh)) / (Monthly light receiving surface solar radiation amount (KWh / m ² )) / Solar cell rated capacity (KW / KW) / m ² ) * 100)
And in order to calculate the loss (%) due to the temperature rise of the solar cell (= (100−monthly temperature coefficient)), the monthly temperature coefficient (%) (= (monthly calculation system power generation amount (KWh)) / month light receiving surface It is characterized by calculating the solar radiation amount (KWh / m ² ) / solar cell rated capacity (KW / KW / m ² ) * 100) and adding it to the system output coefficient. In creating an IV curve for calculation of arbitrary solar radiation intensity and solar cell power generation required for calculation,
{18} Voltage V, current I, photovoltaic current IL at a solar radiation intensity of 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{19} A function obtained by differentiating the function Func (V, I, IL, Co, n, Rsh, Rs, T) with a variable V: Div (V, I, IL, Co, n, Rsh, Rs, T) make,
Specifications of {20} solar cells (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )), short circuit current Isca, optimum current Iopa, optimum voltage Vopa, open circuit Select points P1 (0, Isca), P2 (Vopa, Iopa), P3 (Voca, 0) of voltage Voca and any P4 (V4a, I4a) not close to these three points,
{21} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 T of the reference state temperature Ta (298K), the values of the points P1, P2, P3, and P4 Substituting and using IL, Co, n, Rsh, Rs as unknowns: Func (0, Isca, IL, Co, n, Rsh, Rs, Ta) = 0,
Relational expression: Func (Voca, 0, IL, Co, n, Rsh, Rs, Ta) = 0,
Relational expression: Func (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0
Formula: Func (V4a, I4a, IL, Co, n, Rsh, Rs, Ta) = 0
{22} Substituting the value (Vopa, Iopa) of the point P2 of the reference state temperature Ta (298 K) into the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0. , IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, then
{23} The five relational expressions: Func (0, Isca, IL, Co, n, Rsh, Rs, Ta) = 0, Func (Voca, 0, IL, Co, n, Rsh, Rs, Ta) = 0 , Func (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, Div (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, Func (V4a, I4a, IL , Co, n, Rsh, Rs, Ta) = 0, a solution A (ILa, Coa, na, Rsha, Rsa) is calculated by a non-linear solution program.
{24} Similar to the standard state of the solar cell, the short circuit current Iscb is the specification value at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) , Select the point P1 (0, Iscb), P2 (Vopb, Iopb), P3 (Vocb, 0), P4 (V4b, I4b) of the optimal current Iopb, optimal voltage Vopb, open circuit voltage Vocb,
{25} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 and the second temperature Tb (313 K), and the {07} P1, P2, P3, P4 Substituting the values of the points, IL, Co, n, and Rsh are unknown relations: Func (0, Iscb, IL, Co, n, Rsh, Rs, Tb) = 0,
Relational expression: Func (Vocb, 0, IL, Co, n, Rsh, Rs, Tb) = 0,
Relational expression: Func (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0
Formula: Func (V4b, I4b, IL, Co, n, Rsh, Rs, Tb) = 0
{26} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value (Vopb, Iopb) of the {24} point P2 of the second temperature Tb (313K) , And IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, then
{27} The five relational expressions: Func (0, Iscb, IL, Co, n, Rsh, Rs, Tb) = 0, Func (Vocb, 0, IL, Co, n, Rsh, Rs, Tb) = 0 , Func (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, Div (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, Func (V4b, I4b, IL , Co, n, Rsh, Rs, Tb) = 0, a solution A (Ilb, Cob, nb, Rshb, Rsb) is calculated by a nonlinear solution program.
{28} The short circuit current Iscc, which is the specification value at the third solar cell module temperature Tc (328 K (tc = 55 ° C)) and solar radiation intensity Ec (1 kW / m ² )) as in the standard state of the solar cell Select the points P1 (0, Iscc), P2 (Vopc, Iopc), P3 (Vocc, 0), P4 (V4c, I4c) of the optimal current Iopc, optimal voltage Vopc, and open-circuit voltage Vocc,
{29} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 and the third temperature Tc (328 K), the {28} P1, P2, P3, P4 Substituting the value of the point and making IL, Co, n, Rsh, Rs unknowns: Func (0, Iscc, IL, Co, n, Rsh, Rs, Tc) = 0,
Relational expression: Func (Vocc, 0, IL, Co, n, Rsh, Rs, Tc) = 0
Relational expression: Func (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0,
Formula: Func (V4b, I4b, IL, Co, n, Rsh, Rs, Tc) = 0
{30} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value (Vopc, Iopc) of the point P2 of the {28} at the third temperature Tc (328 K) , And IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, then
{31} The five relational expressions: Func (0, Iscc, IL, Co, n, Rsh, Rs, Tc) = 0, Func (Vocc, 0, IL, Co, n, Rsh, Rs, Tc) = 0 , Func (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, Div (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, Func (V4b, I4b, IL , Co, n, Rsh, Rs, Tc) = 0, a solution A (Ilc, Coc, nc, Rshc, Rsc) is calculated by a nonlinear solution program.
{32} Measured solar radiation intensity to be evaluated Ej, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273) and the values of generated voltage Vj−generated current Ij under these conditions,
{33} Solution A (ILa, Coa, na, Rsha, Rsa) of {23} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) at the reference state, the temperature Solution B (ILb, Cob, nb, Rshb, Rsb) of {27} at tb (Celsius: Tb = tb + 273), Solution C (ILc, Coc) of {31} at temperature tc (Celsius: Tc = tc + 273) , nc, Rshc, Rsc) for each (IL, Co, n, Rsh, Rs), curve interpolation is performed for three points, and the characteristic value M (ILm, Com, nm, Rshm, Rsm), then
After correcting {34} ILm by IL'm = Ilm * Ej / Ea by the measured solar radiation intensity Ej, the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL ', Com, nm, Rshm, Rsm, Tj) = 0, and voltage (V) -current (I ) Relationship (about 40-50 points) using a nonlinear solution program, create a voltage (V) -current (I) relationship or an IV curve and PV curve connecting them, and use that curve. Features.

The method for evaluating the power generation amount of the solar power generation system according to claim 4 is:
Monthly system output coefficient (%) of the target solar power generation system (= (Monthly measured system power generation amount (KWh)) / (Monthly light receiving surface solar radiation amount (KWh / m ² )) / Solar cell rated capacity (KW / KW) / m ² ) * 100)
And in order to calculate the loss (%) due to the temperature rise of the solar cell (= (100−monthly temperature coefficient)), the monthly temperature coefficient (%) (= (monthly calculation system power generation amount (KWh)) / month light receiving surface A method for calculating the amount of solar radiation (KWh / m ² ) / solar cell rated capacity (KW / KW / m ² ) * 100) and evaluating it by a value added to the system output coefficient. In creating an IV curve for calculating the power generation amount of any solar radiation intensity and solar cell temperature necessary for power generation amount calculation,
{35} Voltage V, current I, photovoltaic current IL at a solar radiation intensity of 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{36} n points P1 (V1a, I1a), P2 given by the manufacturer in the standard state of the solar cell (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )) (V2a, I2a), P3 (V3a, I3a),... PN (VNa, INa) to the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Create n relational expressions Func (V, I, IL, Co, n, Rsh, Rs, Ta) = 0
{37} Solving Ila, Coa, na, Rsha, Rsa most suitable for the n relational expressions by a mathematical method such as a least squares problem solution,
{38} n points given by the manufacturer at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) as in the standard state of the solar cell P1 (V1b, I1b), P2 (V2b, I2b), P3 (V3b, I3b),... PN (VNb, Inb), and the above relation: Func (V, I, IL, Co, n, Rsh , Rs, T) = 0 and create n relations Func (V, I, IL, Co, n, Rsh, Rs, Tb) = 0
{39} Ilb, Cob, nb, Rshb, Rsb most suitable for the n relational expressions are solved by a mathematical method such as a method of least squares, and then
{40} n points given by the manufacturer at the third solar cell module temperature Tb (328K (tb = 55 ° C)) and solar radiation intensity Eb (1 kW / m ² )) as in the standard state of solar cells P1 (V1c, I1c), P2 (V2c, I2c), P3 (V3c, I3c), ... PN (VNc, Inc), and the above relation: Func (V, I, IL, Co, n, Rsh , Rs, T) = 0 and create n relations Func (V, I, IL, Co, n, Rsh, Rs, Tc) = 0
{41} Solving Ilc, Coc, nc, Rshc, Rsc most suitable for the n relational expressions by a mathematical method such as a least squares problem solution,
{42} Measured solar radiation intensity Ej to be evaluated, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273), and each value of generated voltage Vj−generated current Ij under these conditions,
{43} Solution A (ILa, Coa, na, Rsha, Rsa) of {37} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) at the reference state, the temperature Solution B (ILb, Cob, nb, Rshb, Rsb) of {39} at tb (Celsius: Tb = tb + 273), Solution C (ILc, Coc) of {41} at temperature tc (Celsius: Tc = tc + 273) , nc, Rshc, Rsc) for each (IL, Co, n, Rsh, Rs), curve interpolation is performed for three points, and characteristic value M (ILm, Com, at measured temperature tj (Celsius: Tj = tj + 273)) nm, Rshm, Rsm), then
{44} ILm is corrected by IL'm = Ilm * Ej / Ea based on the measured solar radiation intensity Ej, and then the relation: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. It is characterized by.

The method for evaluating the power generation amount of the solar power generation system according to claim 5 is:
System output coefficient after temperature correction (= (actual output (KWh)) / irradiance (KWh / m ² ) / solar cell area (m ² ) * for a certain time (about 10 minutes to 1 hour) of the target photovoltaic power generation system * (Maximum power at 25 ° C. (Pmax) (KW)) / (maximum power at measurement temperature (Pmax) (KW)) * (solar cell rated capacity (KW / KW / m ² )) / reference solar radiation (KWh / m ² ) (= 1) / Solar cell area (m ² ) * 100) In the calculation of Pmax at 25 ° C. and Pmax at the measurement temperature, the solar cell IV having an arbitrary solar radiation intensity and solar cell temperature In the method of creating a curve, a method of converting an IV curve of a standard solar cell (“practical IV curve creation method”) or a method of solving a basic formula of a solar cell (“IV curve creation by theoretical formula”) Method)) to calculate the amount of power generated by the solar power generation system. Characterized in that it deserves.

The method for evaluating the power generation amount of the solar power generation system according to claim 6 is:
Temperature-corrected system output coefficient (= (actual output (KWh)) / insolation (KWh / m ² ) / solar cell area (m ² ) * for a certain time (about 10 minutes to 1 hour) of the target photovoltaic power generation system (Maximum power at 25 ° C. (Pmax) (KW)) / (Maximum power at measurement temperature (Pmax) (KW))) * (Solar cell rated capacity (KW / KW / m ² )) / Reference solar radiation (KWh / m ² ) (= 1) / Solar cell area (m ² ) * 100) is an evaluation method characterized by an average value of about 1 to 3 hours, and Pmax at 25 ° C. and measurement temperature is calculated. In the process, in the creation of IV curve of arbitrary solar radiation intensity and solar cell temperature,
{45} Voltage V, current I, photovoltaic current IL, solar current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) at 1 kW / m ² of solar radiation intensity Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{46} A function obtained by differentiating the function Func (V, I, IL, Co, n, Rsh, Rs, T) with a variable V: Div (V, I, IL, Co, n, Rsh, Rs, T) make,
{47} Specification values for solar cells (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )), short circuit current Isca, optimum current Iopa, optimum voltage Vopa, open circuit Select point P1 (0, Isca), P2 (Vopa, Iopa), P3 (Voca, 0) of voltage Voca,
{48} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 where T is the reference state temperature Ta (298K), the series resistance Rs is the specification value Rsa at the reference temperature, and Substituting the values of the points of P1, P2, P3 and IL, Co, n, Rsh as unknowns: Func (0, Isca, IL, Co, n, Rsh, Rsa, Ta) = 0,
Relational expression: Func (Voca, 0, IL, Co, n, Rsh, Rsa, Ta) = 0,
Formula: Func (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0
{49} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value Rsa and the value of the point P2 (Vopa , Iopa) and IL, Co, n, Rsh as unknowns,
Create the relation: Div (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0, then
{50} The above four relational expressions: Func (0, Isca, IL, Co, n, Rsh, Rsa, Ta) = 0, Func (Voca, 0, IL, Co, n, Rsh, Rsa, Ta) = 0 , Func (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0, Div (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0 , na, Rsha) is calculated by a nonlinear solution program, then
{51} Similar to the standard state of the solar cell, the short-circuit current Iscb is the specification value at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) , Select points P1 (0, Iscb), P2 (Vopb, Iopb), P3 (Vocb, 0) of the optimal current Iopb, optimal voltage Vopb, open circuit voltage Vocb,
{52} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0, the second temperature Tb (313K) at T, the series resistance Rs, the specification value Rsb at the temperature, and Substituting the values of the points P1, P2, P3, and IL, Co, n, Rsh as unknowns, a relational expression: Func (0, Iscb, IL, Co, n, Rsh, Rsb, Tb) = 0,
Relational expression: Func (Vocb, 0, IL, Co, n, Rsh, Rsb, Tb) = 0
Formula: Func (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0
{53} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value Rsb at the second temperature and the series resistance Rs of the second temperature Tb (313K) Substituting the value of point P2 (Vopb, Iopb) and making IL, Co, n, Rsh unknown
Create the relation: Div (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0, then
{54} The above four relational expressions: Func (0, Iscb, IL, Co, n, Rsh, Rsb, Tb) = 0, Func (Vocb, 0, IL, Co, n, Rsh, Rsb, Tb) = 0 , Func (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0, Div (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0 satisfying solution A (Ilb, Cob , nb, Rshb) by a non-linear solution program, then
{55} The short circuit current Iscc, which is the specification value at the third solar cell module temperature Tc (328 K (tc = 55 ° C)) and solar radiation intensity Ec (1 kW / m ² )) as in the standard state of the solar cell. Select points P1 (0, Iscc), P2 (Vopc, Iopc), P3 (Vocc, 0) for the optimal current Iopc, optimal voltage Vopc, and open-circuit voltage Vocc,
{56} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 at a third temperature Tc (328K), a series resistance Rs at the specified value Rsc, and Substituting the values of the points P1, P2, and P3 of {55}, IL, Co, n, and Rsh are unknowns: Func (0, Iscc, IL, Co, n, Rsh, Rsc, Tc) = 0,
Relational expression: Func (Vocc, 0, IL, Co, n, Rsh, Rsc, Tc) = 0
Create a relational expression: Func (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0
{57} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the series resistance Rs of the third temperature Tc (328K) has a value Rsc at the third temperature and Substituting the value (Vopc, Iopc) of the point P2 of {55} and making IL, Co, n, Rsh unknown
Create the relation: Div (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0, then
{58} The above four relational expressions: Func (0, Iscc, IL, Co, n, Rsh, Rsc, Tc) = 0, Func (Vocc, 0, IL, Co, n, Rsh, Rsc, Tc) = 0 , Func (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0, Div (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0 satisfying solution A (Ilc, Coc , nc, Rshc) by a non-linear solution program, then
{59} Measured value of solar cell to be evaluated Solar radiation intensity Ej, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273), and each value of generated voltage Vj−generated current Ij under these conditions,
{60} Solution A (ILa, Coa, na, Rsha) of {50} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) in the reference state, the temperature tb ( Celsius: solution B (ILb, Cob, nb, Rshb) of {54} at Tb = tb + 273), solution C (ILc, Coc, nc, Rshc) of {58} at temperature tc (celsius: Tc = tc + 273) ) And curve interpolation at three points for each of the input values Rsa, Rsb, Rsa, Rsc (IL, Co, n, Rsh, Rs), and the characteristic value M at the measured temperature tj (Celsius: Tj = tj + 273) (ILm, Com, nm, Rshm, Rsm) is calculated, then
{61} ILm is corrected by IL'm = Ilm * Ej / Ea based on the measured solar radiation intensity Ej, and then the relationship: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. It is characterized by.

The method for evaluating the amount of power generation of the solar power generation system according to claim 7 is:
Temperature-corrected system output coefficient (= (actual output (KWh)) / insolation (KWh / m ² ) / solar cell area (m ² ) * for a certain time (about 10 minutes to 1 hour) of the target photovoltaic power generation system (Maximum power at 25 ° C. (Pmax) (KW)) / (Maximum power at measurement temperature (Pmax) (KW))) * (Solar cell rated capacity (KW / KW / m ² )) / Reference solar radiation (KWh / m ² ) (= 1) / Solar cell area (m ² ) * 100) is an evaluation method characterized by an average value of about 1 to 3 hours, and Pmax at 25 ° C. and measurement temperature is calculated. In the process, create an IV curve of arbitrary solar radiation intensity and solar cell temperature. {62} Voltage V, current I, photovoltaic current IL at solar radiation intensity 1kW / m ² , saturation current temperature coefficient Co, junction constant n , Function including the parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature): Func (V, I, I L, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)- Create (V + Rs * I) / Rsh-I, then
{63} A function obtained by differentiating the function Func (V, I, IL, Co, n, Rsh, Rs, T) with a variable V: Div (V, I, IL, Co, n, Rsh, Rs, T) make,
Specifications in {64} solar cells (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )), short circuit current Isca, optimum current Iopa, optimum voltage Vopa, open circuit Select points P1 (0, Isca), P2 (Vopa, Iopa), P3 (Voca, 0) of voltage Voca and any P4 (V4a, I4a) not close to these three points,
{65} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 is set to the reference state temperature Ta (298K) and the values of the points P1, P2, P3, and P4 to T Substituting and using IL, Co, n, Rsh, Rs as unknowns: Func (0, Isca, IL, Co, n, Rsh, Rs, Ta) = 0,
Relational expression: Func (Voca, 0, IL, Co, n, Rsh, Rs, Ta) = 0,
Relational expression: Func (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0
Formula: Func (V4a, I4a, IL, Co, n, Rsh, Rs, Ta) = 0
{66} Substituting the value of the point P2 (Vopa, Iopa) of the reference state temperature Ta (298 K) into the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0 , IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, then
{67} The five relational expressions: Func (0, Isca, IL, Co, n, Rsh, Rs, Ta) = 0, Func (Voca, 0, IL, Co, n, Rsh, Rs, Ta) = 0 , Func (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, Div (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, Func (V4a, I4a, IL , Co, n, Rsh, Rs, Ta) = 0, a solution A (ILa, Coa, na, Rsha, Rsa) is calculated by a non-linear solution program.
{68} Similar to the standard state of the solar cell, the short circuit current Iscb is the specification value at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) , Select the point P1 (0, Iscb), P2 (Vopb, Iopb), P3 (Vocb, 0), P4 (V4b, I4b) of the optimal current Iopb, optimal voltage Vopb, open circuit voltage Vocb,
{69} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0, the second temperature Tb (313K), and the {51} P1, P2, P3, P4 Substituting the values of the points, IL, Co, n, and Rsh are unknown relations: Func (0, Iscb, IL, Co, n, Rsh, Rs, Tb) = 0,
Relational expression: Func (Vocb, 0, IL, Co, n, Rsh, Rs, Tb) = 0,
Relational expression: Func (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0
Formula: Func (V4b, I4b, IL, Co, n, Rsh, Rs, Tb) = 0
{70} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value (Vopb, Iopb) of the {68} point P2 of the second temperature Tb (313K) , And IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, then
{71} The five relational expressions: Func (0, Iscb, IL, Co, n, Rsh, Rs, Tb) = 0, Func (Vocb, 0, IL, Co, n, Rsh, Rs, Tb) = 0 , Func (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, Div (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, Func (V4b, I4b, IL , Co, n, Rsh, Rs, Tb) = 0, a solution A (Ilb, Cob, nb, Rshb, Rsb) is calculated by a nonlinear solution program.
{72} The short circuit current Iscc, which is the specification value at the third solar cell module temperature Tc (328 K (tc = 55 ° C)) and solar radiation intensity Ec (1 kW / m ² )) as in the standard state of the solar cell Select the points P1 (0, Iscc), P2 (Vopc, Iopc), P3 (Vocc, 0), P4 (V4c, I4c) of the optimal current Iopc, optimal voltage Vopc, and open-circuit voltage Vocc,
{73} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 and the third temperature Tc (328 K), the values of the points of P1, P2, P3, and P4 Where IL, Co, n, Rsh, Rs are unknowns: Func (0, Iscc, IL, Co, n, Rsh, Rs, Tc) = 0,
Relational expression: Func (Vocc, 0, IL, Co, n, Rsh, Rs, Tc) = 0
Relational expression: Func (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0,
Formula: Func (V4b, I4b, IL, Co, n, Rsh, Rs, Tc) = 0
{74} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value (Vopc, Iopc) of the {72} point P2 at the third temperature Tc (328 K) , And IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, then
{75} The five relational expressions: Func (0, Iscc, IL, Co, n, Rsh, Rs, Tc) = 0, Func (Vocc, 0, IL, Co, n, Rsh, Rs, Tc) = 0 , Func (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, Div (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, Func (V4b, I4b, IL , Co, n, Rsh, Rs, Tc) = 0, a solution A (Ilc, Coc, nc, Rshc, Rsc) is calculated by a nonlinear solution program.
{76} Measured solar radiation intensity Ej to be evaluated, solar cell module temperature tj (degrees Celsius: absolute temperature Tj = tj + 273), and each value of generated voltage Vj−generated current Ij under these conditions,
{77} Solution A (ILa, Coa, na, Rsha, Rsa) of {67} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) at the reference state, the temperature Solution B (ILb, Cob, nb, Rshb, Rsb) of {71} at tb (Celsius: Tb = tb + 273), Solution C (ILc, Coc) of {75} at temperature tc (Celsius: Tc = tc + 273) , nc, Rshc, Rsc) for each (IL, Co, n, Rsh, Rs), curve interpolation is performed at three points, and the characteristic value M (ILm, Com, at measured temperature tj (Celsius: Tj = tj + 273)) nm, Rshm, Rsm), then
After correcting {78} ILm by IL'm = Ilm * Ej / Ea by the measured solar radiation intensity Ej, the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. It is characterized by.

The method for evaluating the power generation amount of the solar power generation system according to claim 8 is:
Temperature-corrected system output coefficient (= (actual output (KWh)) / insolation (KWh / m ² ) / solar cell area (m ² ) * for a certain time (about 10 minutes to 1 hour) of the target photovoltaic power generation system (Maximum power at 25 ° C. (Pmax) (KW)) / (Maximum power at measurement temperature (Pmax) (KW))) * (Solar cell rated capacity (KW / KW / m ² )) / Reference solar radiation (KWh / m ² ) (= 1) / Solar cell area (m ² ) * 100) is an evaluation method characterized by an average value of about 1 to 3 hours, and Pmax at 25 ° C. and measurement temperature is calculated. In the process, in the creation of IV curve of arbitrary solar radiation intensity and solar cell temperature,
{76} Voltage V, current I, photovoltaic current IL at solar intensity 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{77} n points P1 (V1a, I1a), P2 given by the manufacturer in the standard state of the solar cell (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )) (V2a, I2a), P3 (V3a, I3a),... PN (VNa, INa) to the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Create n relational expressions Func (V, I, IL, Co, n, Rsh, Rs, Ta) = 0
{78} Solving Ila, Coa, na, Rsha, Rsa most suitable for the n relational expressions by a mathematical method such as a least squares problem solution,
{79} n points given by the manufacturer at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) as in the standard state of solar cells P1 (V1b, I1b), P2 (V2b, I2b), P3 (V3b, I3b),... PN (VNb, Inb), and the above relation: Func (V, I, IL, Co, n, Rsh , Rs, T) = 0 and create n relations Func (V, I, IL, Co, n, Rsh, Rs, Tb) = 0
{80} Solving Ilb, Cob, nb, Rshb, Rsb most suitable for the n relational expressions by a mathematical method such as a method of least squares problem,
{81} n points given by the manufacturer at the third solar cell module temperature Tb (328K (tb = 55 ° C)) and solar radiation intensity Eb (1 kW / m ² )) as in the standard state of solar cells P1 (V1c, I1c), P2 (V2c, I2c), P3 (V3c, I3c), ... PN (VNc, Inc), and the above relation: Func (V, I, IL, Co, n, Rsh , Rs, T) = 0 to create n relations Func (V, I, IL, Co, n, Rsh, Rs, Tc) = 0
{82} Solving Ilc, Coc, nc, Rshc, Rsc most suitable for the n relational expressions using a mathematical method such as a least squares problem solution,
{83} Measured solar radiation intensity Ej to be evaluated, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273), and each value of generated voltage Vj−generated current Ij under these conditions,
{84} Solution A (ILa, Coa, na, Rsha, Rsa) of {78} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) at the reference state, the temperature Solution B (ILb, Cob, nb, Rshb, Rsb) of {80} at tb (Celsius: Tb = tb + 273), Solution C (ILc, Coc) of {82} at temperature tc (Celsius: Tc = tc + 273) , nc, Rshc, Rsc) for each (IL, Co, n, Rsh, Rs), curve interpolation is performed for three points, and characteristic value M (ILm, Com, at measured temperature tj (Celsius: Tj = tj + 273)) nm, Rshm, Rsm), then
{85} ILm is corrected by IL'm = Ilm * Ej / Ea by the measured solar radiation intensity Ej, and then the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. It is characterized by.

The method for evaluating the amount of power generation of the solar power generation system according to claim 9 is:
The measurement data used for the evaluation in claims 5, 6, 7, and 8 are as follows: the solar radiation temperature is around 25 ° C., the solar radiation intensity is about 850 W / m ² or more, or the solar radiation intensity is 1000 W / m ^2.
In other words, the power generation amount is evaluated by data obtained from a stable value of about 1 to 3 hours.

A computer-readable storage medium according to claim 10 is provided.
Recording a processing program to be processed by the photovoltaic power generation evaluation method according to claim 1, claim 2, claim 3, claim 4, claim 5, claim 6, claim 7, claim 8, or claim 9. It is characterized by.

The photovoltaic power generation evaluation device / system according to claim 11 is:
A computer capable of operating the recording medium according to claim 10.

  Here, terms, functions, techniques, etc. relating to the present invention will be described.

(1) “Solar cell temperature” is also referred to as “solar cell module temperature” or “module temperature”, and is usually measured by a thermocouple embedded in the cells of the solar cell module. The solar cell is called by the name of (solar cell) cell → (solar cell) module → (solar cell) array according to the stage of its configuration.

(2) Regarding the symbols used for the solar cell temperature, t (° C.) shown in lower case indicates Celsius, and T (K (Kelvin)) shown in upper case indicates absolute temperature. That is, T (K) = t (° C.) + 273. The capital letter T is mainly used in solar cell basic formulas, and the lowercase letter t is often used elsewhere.

(3) Regarding the solar cell output / power generation amount, the product of the instantaneous generation voltage V of the solar cell and the instantaneous generation current I is called the solar cell output (unit W or KW), and the time integral value is the power generation amount (electric power). Amount) (units Wh or KWh).

(4) The basic characteristic formula of the solar cell is the following formula.
_{I = IL-Co * T 3} * exp (-mqEg / nKoT) * (exp (q (V + RsI) / nKoT) -1) - (V + RsI) / Rsh
Here, each symbol is as follows.
I: Output current [A] Co: Saturation current temperature coefficient V: Output voltage [V] Eg: Energy gap [eV]
IL: Photovoltaic current [A] T: Solar cell element absolute temperature [K]
IO: Saturation current [A] Ko: Boltzmann constant [J / K]
Rs: DC resistance [Ω] q: Charge amount of electrons [° C.]
Rsh: parallel resistance [Ω] n: junction constant
m: Number of cells constituting a module (there is no description in the present invention)

The above formula is a theoretical formula based on the basic characteristics of the semiconductor. To find each point on the IV curve from this equation, move I on the left side of this equation to the right side.
Func (V, I, IL, Co, n, Rsh, Rs, T)
_{= IL-Co * T 3 *} exp (-qEg / nKoT) * (exp q (V + RsI) / nKoT-1) - (V + RsI) / Rsh-I
The IV curve can be obtained by substituting the basic characteristic values (IL, Co, n, Rsh, Rs) and solving the relationship between V and I with a nonlinear solution program.

(5) In the present invention, the characteristic values are properly used as follows.
(a) (Solar cell) Basic characteristic values: IL, Co, n, Rsh, Rs
(b) (Solar cell) Characteristic values: Isc, Iop, Vop, Voc, α, β, Rs, K
As described above, Rs is used in both (1) and (2).

(6) The conversion formula is as follows.
(a) “Practical IV curve conversion formula”
I ₁ = I ₂ + Isc * (E ₁ / E ₂ −1) + α * (t ₁ −t ₂ )
V ₁ = V ₂ + β * (t ₁ −t ₂ ) −Rs * (I ₁ −I ₂ ) −K * I ₁ * (t ₁ −t ₂ )
(b) Inverse transformation formula of “practical IV curve transformation formula” (inverse application)
((About V _2, I ₂ of formula 1) is a modification by solving the equation)
I ₂ = I ₁ + Isc * (E ₂ −E ₁ ) / E ₂ + α (t ₂ −t ₁ )
_{V 2 = V 1 + β *} (t 2 -t 1) -Rs * (I 2 -I 1) -K * I 1 * (t 2 -t 1)
Here, (1) and (2) are similar to JIS8913, 8914, and 8919 formulas that are generally known, but are different and excellent formulas as described below. In particular, the expression (1) was filed in Japanese Patent Application No. 6-2626 and published in IEEJ Paper 2 and others.
In addition, the symbols used in these equations are V ₂ , I ₂ , E ₂ , T _2, or arbitrary conditions (measurement conditions) for the voltage value, current value, solar radiation intensity, and solar cell temperature in the reference state, respectively. Are V ₁ , I ₁ , E ₁ , and T ₁ .
Also, Isc: short circuit current (A)
Iop: Optimum current (A)
Vop: Optimum voltage (V)
Voc: Open circuit voltage (V)
α: Fluctuation value of Isc when temperature changes by 1 ° C (A / ° C)
β: Fluctuation value of Voc when temperature changes by 1 ° C (V / ° C)
Rs: Module series resistance (Ω)
K: Curve correction factor (Ω / ° C.).
The lower columns (1) and (2) in FIG. 4 are “practical IV curve conversion equations”, and the right columns (3) and (4) in FIG. 4 are “practical IV curve conversion equations”. It is equivalent to the reverse application of.
The list of voltage-current values in the reference state and the voltage-current value conversion formula in the measurement solar radiation intensity / solar cell temperature condition is shown in FIG. 4 as described above. This figure was published in IEEJ Paper 3 (Iga: “Solar Cell Solar Radiation Meter Using Practical IV Curve Making Method”, Electrical Engineering D, Vol. 117, No. 10, 1997). However, in the inventor's formula, in the lower column, as described above, Japanese Patent Application No. 6-2626 filed a patent application before publication of the paper. In general, the expression in the leftmost or center column is still used, and the same is used in the “IV curve measuring device”.

Here, the application method and characteristics of the conversion equations (1) and (2) will be further described.
The expressions (1) and (2) used in the present invention and the JIS correction expressions ((3) 'and (4)'), the CEI IEC expression, and the IEEE expression seem to be very similar on a first glance. As shown in Fig. 4, the solar radiation intensity and solar cell temperature conditions for voltage V and current I are completely different, as well as the solar radiation intensity and solar cell temperature conditions for Isc, α, β, Rs, and K are completely different. ing. In the formulas (1) and (2) applied by the inventor, voltage, current, and Isc, α, β, Rs, and K are all in the standard state (intensity of solar radiation 1 KW / m ² , solar cell temperature 25 )), And there is no other application method like this.
By applying such a method, as described in this specification, the voltage-current characteristic curve (IV curve) and the voltage-power characteristic curve (PV curve) of the measurement conditions with high accuracy and versatility are provided. This is useful for evaluating solar cells and predicting power generation.
The reason why the IV curve and PV curve of solar radiation intensity and solar cell temperature conditions at the time of measurement can be obtained by applying this formula (Equation (1), (2)) with good accuracy and applicability is as follows. .
(A) The parameters and characteristic values of the standard state are disclosed by the solar cell manufacturer, and these values at other solar radiation intensities and solar cell temperatures are hardly shown. Since the present invention is based on using the value of the reference state, the present invention has wide applicability.
Further, as in other methods, it is not preferable in terms of calculation accuracy and handling to mix and apply various solar radiation intensity and solar cell temperature condition parameters and characteristic values.
(B) When comparing and evaluating the characteristics of solar cells, it is more direct and preferable to convert the reference value to the measurement condition and compare it with the measured value, rather than processing the measured value and comparing it with the reference value. it can.

When evaluating the output and power generation amount of a photovoltaic power generation system, the measurement method can be broadly classified into the following two types.
(1) Measurement by disconnecting the photovoltaic power system from the interconnected operation state Disconnecting the solar cell from the system, connecting an “IV curve measuring device”, and continuously changing the simulated load resistance value to generate voltage and current Measure the relationship of n sets of values (for example, several tens of sets), create a voltage-current curve (IV curve) of the solar cell, convert it to the IV curve of the reference state, etc. evaluate.
(2) Measuring voltage and current while the photovoltaic power generation system is in a linked operation state Measure and evaluate solar radiation intensity, solar cell temperature, output voltage and current, etc. while in a linked state.
The present invention relates to (2) the method.

Since various losses of the target photovoltaic power generation system can be grasped stably and accurately based on the value of “system output coefficient” + “loss due to solar cell temperature rise” calculated according to claims 1 to 4, This leads to improved efficiency.
In Claim 1, since various methods can be used for the solar cell IV curve preparation method required for evaluation, it can be said that it is a versatile evaluation method with wide applicability.
According to claim 2, a solar cell characteristic value is given by the manufacturer as a solar cell characteristic value in addition to the short-circuit current Isc, the optimum current Iop, the optimum voltage Vop, and the open-circuit voltage Voc, so that an IV curve can be created. Can be evaluated.
According to claims 3 and 4, the solar cell characteristic value from the manufacturer includes one or more points other than these points on the IV curve, such as short-circuit current Isc, optimum current Iop, optimum voltage Vop, open-circuit voltage Voc. Is given, an IV curve can be created and evaluated even if the series resistance Rs is not given.
Claims 5 to 8 are methods in which the value of “system output coefficient” + “loss due to solar cell temperature rise” can be directly obtained, and can be obtained by a measured value of about 1 to 3 hours. Can be evaluated by value.
In Claim 5, since various methods can be used for the solar cell IV curve preparation method required for evaluation, it can be said that it is a versatile evaluation method with wide applicability.
According to claim 6, an IV curve can be created by providing a solar cell series resistance Rs in addition to the short circuit current Isc, the optimum current Iop, the optimum voltage Vop, and the open circuit voltage Voc from the manufacturer as the solar cell characteristic value. Can be evaluated.
According to claims 7 and 8, the solar cell characteristic value from the manufacturer includes one or more points other than these points on the IV curve, such as short circuit current Isc, optimum current Iop, optimum voltage Vop, open circuit voltage Voc. Is given, an IV curve can be created and evaluated even if the series resistance Rs is not given.
In claim 9, by using the data of the solar radiation intensity and solar cell temperature conditions close to the reference state, even if there is an error in the characteristic value obtained from the manufacturer, an accurate evaluation can be performed without being affected by the error.
According to claims 10 and 11, an apparatus / system capable of carrying out the present evaluation method can be manufactured, and can be linked to practical use.

Next, an embodiment of the present invention will be described with reference to the main drawings.
Figure 1 shows an example of evaluation of the amount of power generated by a photovoltaic power generation system. The value (related to claims 1 to 4) obtained by adding "loss due to temperature rise (temperature characteristic part)" to "system output coefficient" is very large throughout the year. You can see that there is no change. That is, the ratio of various losses of the target photovoltaic power generation system can be understood from this value. By changing the measurement position of the power generation amount, it leads to the elucidation of various loss factors. Moreover, it can be seen that the mark X (related to claims 5 to 9) is not significantly different from the above values, and that even if the solar radiation intensity / solar cell temperature conditions are adjusted, it can be evaluated even for measurement for about 1 to 3 hours.
FIG. 2 is a flowchart of an IV curve creation method based on a theoretical formula. When the solar cell characteristic value (Isc, Vop, Iop, Voc) at 25 ° C and the Rs, α, β, K at 25 ° C are given, and the battery characteristic value at 25 ° C, 40 ° C, 55 ° C ( Isc, Vop, Iop, Voc) and a method of creating an IV curve and PV curve of arbitrary solar radiation intensity and temperature when Rs of 25 ° C. is given. Although not shown in the figure, if the solar cell characteristic value (Isc, Vop, Iop, Voc) and one or more points other than these points on the IV curve are given, the IV curve is similarly obtained. Can be created.
Claims 1 to 9 of the present invention show a method of creating and evaluating an IV curve from various input conditions by a solution based on the Newton-Raphson method. Claims 1 and 5 include a method based on a “practical IV curve creation method”. Moreover, as long as it is a creation method of the IV curve in arbitrary solar radiation intensity and solar cell temperature, it is not limited to the method described in this claim, This evaluation method is applicable.
FIG. 8 explains the contents of claims 5 to 9 and shows a method of calculating the temperature-corrected system output coefficient (reference (temperature) output coefficient). In the figure, a typical “IV curve creation method based on a theoretical formula” is shown as an IV curve creation method, but various methods can be applied as described above. The calculation method of the solar cell conversion efficiency (“conversion efficiency after temperature correction”) at the reference temperature (25 ° C.) and the output coefficient of the reference temperature (25 ° C.) is shown by equation (1) in the figure.

It is an example of the electric power generation amount evaluation result of a solar power generation system. It is a flowchart of the IV curve creation method by a theoretical formula. This is the power generation principle of solar cells. Conversion formulas ((3), (4) and (3) ', (4)') to the IV curve value in the standard condition IV intensity and solar cell temperature conditions, and vice versa It is a figure of explanation of the formula (lower column (1), (2) formula of the figure) (The Institute of Electrical Engineers of Japan paper 3: “Solar cell pyranometer using the practical IV curve creation method, Electrotechnical D, Vol. 117, 10” No., 1997. ”As mentioned above, in this table, subscript 1 represents the solar radiation intensity and solar cell temperature conditions during measurement, and subscript 2 represents the reference state (solar radiation intensity 1 kw / m ² , solar cell temperature 25 ° C.). Note that the usage of the subscript 1.2 in the text of the present invention is reversed. It is explanatory drawing of a solar cell output characteristic curve (IV, PV curve). This is a relational expression between solar cell basic characteristic values (Iph, Io, Rs, Rsh) and solar cell absolute temperature (Tp) proposed by the Japan Quality Assurance Organization. By this formula, these basic characteristic values at different temperatures can be obtained by calculation. This is a method for creating an IV curve of the solar radiation intensity and solar cell temperature conditions during measurement from the solar cell characteristic values (“practical IV curve creation method”). By using this method, an IV curve of arbitrary solar radiation intensity and solar cell temperature can be obtained without solving the basic formula of the solar cell. It is a calculation flow figure of the system output coefficient (output coefficient of a reference temperature) after temperature correction.

Claims (11)

Monthly system output coefficient (%) of the target solar power generation system (= (Monthly measured system power generation amount (KWh)) / (Monthly light receiving surface solar radiation amount (KWh / m ² )) / Solar cell rated capacity (KW / KW) / m ² ) * 100)
Then, in order to calculate the loss (%) due to the temperature rise of the solar cell (= (100−monthly temperature coefficient)), the monthly temperature coefficient (%) (= monthly calculation system power generation amount (KWh) / month light receiving surface solar radiation amount (KWh / m ² ) / Solar cell rated capacity (KW / KW / m ² ) * 100) Monthly calculation system required for calculation Solar power of any solar radiation intensity and solar cell temperature necessary for calculation of power generation amount As a method for creating a battery IV curve, (1) a method for converting an IV curve of a standard solar cell ("practical IV curve creation method") or (2) a method for solving a solar cell basic equation (“Theoretical formula IV curve creation method”) is used to calculate the loss (%) due to temperature rise, and the system output coefficient plus the loss due to temperature rise,
Evaluation method characterized by evaluating power generation amount of solar power generation system Monthly system output coefficient (%) of the target solar power generation system (= (Monthly measured system power generation amount (KWh)) / (Monthly light receiving surface solar radiation amount (KWh / m ² )) / Solar cell rated capacity (KW / KW) / m ² ) * 100)
And, in the method characterized by evaluating the power generation amount of the photovoltaic power generation system by a value obtained by adding a loss (%) due to a temperature rise of the solar cell (= (100−monthly temperature coefficient)) to the system output coefficient,
Necessary for calculating monthly temperature coefficient (%) (= (Monthly calculation system power generation amount (KWh) / Monthly light receiving surface solar radiation amount (KWh / m ² ) / Solar cell rated capacity (KW / KW / m ² ) * 100) In the IV curve creation method necessary for calculating the power generation amount of any solar radiation intensity and solar cell temperature, which is necessary in the process of calculating the monthly power generation amount,
{01} Voltage V, current I, photovoltaic current IL at a solar radiation intensity of 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{02} A function obtained by differentiating the function Func (V, I, IL, Co, n, Rsh, Rs, T) with a variable V: Div (V, I, IL, Co, n, Rsh, Rs, T) make,
{03} Specification values for solar cells (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )), short circuit current Isca, optimum current Iopa, optimum voltage Vopa, open circuit Select point P1 (0, Isca), P2 (Vopa, Iopa), P3 (Voca, 0) of voltage Voca,
{04} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 where T is the reference state temperature Ta (298 K), the series resistance Rs is the specification value Rsa at the reference temperature, and Substituting the values of the points of P1, P2, P3 and IL, Co, n, Rsh as unknowns: Func (0, Isca, IL, Co, n, Rsh, Rsa, Ta) = 0,
Relational expression: Func (Voca, 0, IL, Co, n, Rsh, Rsa, Ta) = 0,
Formula: Func (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0
{05} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value Rsa and the value of the point P2 (Vopa , Iopa) and IL, Co, n, Rsh as unknowns,
Create the relation: Div (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0, then
{06} The four relational expressions: Func (0, Isca, IL, Co, n, Rsh, Rsa, Ta) = 0, Func (Voca, 0, IL, Co, n, Rsh, Rsa, Ta) = 0 , Func (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0, Div (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0 satisfying solution A (ILa, Coa , na, Rsha) is calculated by a nonlinear solution program, then
{07} Similar to the standard state of the solar cell, the short-circuit current Iscb is the specification value at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) , Select points P1 (0, Iscb), P2 (Vopb, Iopb), P3 (Vocb, 0) of the optimal current Iopb, optimal voltage Vopb, open circuit voltage Vocb,
{08} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0, the second temperature Tb (313K) at T, the series resistance Rs, the specification value Rsb at the temperature, and Substituting the values of the points P1, P2, and P3 of {07}, IL, Co, n, and Rsh are unknown relations: Func (0, Iscb, IL, Co, n, Rsh, Rsb, Tb) = 0,
Relational expression: Func (Vocb, 0, IL, Co, n, Rsh, Rsb, Tb) = 0
Formula: Func (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0
{09} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the series resistance Rs of the second temperature Tb (313K) is set to the value Rsb at the second temperature and the above Substituting the value (Vopb, Iopb) at point P2 of {07}, and making IL, Co, n, and Rsh unknown
Create the relation: Div (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0, then
{10} The four relational expressions: Func (0, Iscb, IL, Co, n, Rsh, Rsb, Tb) = 0, Func (Vocb, 0, IL, Co, n, Rsh, Rsb, Tb) = 0 , Func (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0, Div (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0 satisfying solution A (Ilb, Cob , nb, Rshb) by a non-linear solution program, then
{11} The short circuit current Iscc, which is the specification value at the third solar cell module temperature Tc (328 K (tc = 55 ° C)) and solar radiation intensity Ec (1 kW / m ² )) as in the standard state of the solar cell Select points P1 (0, Iscc), P2 (Vopc, Iopc), P3 (Vocc, 0) for the optimal current Iopc, optimal voltage Vopc, and open-circuit voltage Vocc,
{12} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0, the third temperature Tc (328 K) at T, the series resistance Rs, the specification value Rsc at the temperature, and Substituting the values of the points P1, P2, and P3 of {11}, IL, Co, n, and Rsh are unknowns: Func (0, Iscc, IL, Co, n, Rsh, Rsc, Tc) = 0,
Relational expression: Func (Vocc, 0, IL, Co, n, Rsh, Rsc, Tc) = 0
Create a relational expression: Func (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0
{13} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value Rsc at the third temperature and the series resistance Rs of the third temperature Tc (328 K) and Substituting the value (Vopc, Iopc) of the point P2 of {11} and making IL, Co, n, Rsh unknown
Create the relation: Div (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0, then
{14} The above four relational expressions: Func (0, Iscc, IL, Co, n, Rsh, Rsc, Tc) = 0, Func (Vocc, 0, IL, Co, n, Rsh, Rsc, Tc) = 0 , Func (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0, Div (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0 satisfying solution A (Ilc, Coc , nc, Rshc) by a non-linear solution program, then
{15} Measured value of solar cell to be evaluated Solar radiation intensity Ej, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273), and values of generated voltage Vj−generated current Ij under these conditions,
{16} Solution A (ILa, Coa, na, Rsha) of {06} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) in the reference state, the temperature tb ( Celsius: Tb = tb + 273) {10} solution B (ILb, Cob, nb, Rshb), temperature tc (Celsius: Tc = tc + 273), {14} solution C (ILc, Coc, nc, Rshc) ) And curve interpolation at three points for each of the input values Rsa, Rsb, Rsa, Rsc (IL, Co, n, Rsh, Rs), and the characteristic value M at the measured temperature tj (Celsius: Tj = tj + 273) (ILm, Com, nm, Rshm, Rsm) is calculated, then
After correcting {17} ILm with IL'm = Ilm * Ej / Ea by the measured solar radiation intensity Ej, the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. A method for evaluating the amount of photovoltaic power generation. Monthly system output coefficient (%) of the target solar power generation system (= (Monthly measured system power generation amount (KWh)) / (Monthly light receiving surface solar radiation amount (KWh / m ² )) / Solar cell rated capacity (KW / KW) / m ² ) * 100)
Then, in order to calculate the loss (%) due to the temperature rise of the solar cell (= (100−monthly temperature coefficient)), the monthly temperature coefficient (%) (= (monthly calculation system power generation amount (KWh) / month light receiving surface solar radiation) Amount (KWh / m ² ) / Solar cell rated capacity (KW / KW / m ² ) * 100) is calculated, and is evaluated by the value obtained by adding the loss to the system output coefficient. Necessary for this calculation In the IV curve creation method for calculating the power generation amount of any solar radiation intensity and solar cell temperature necessary for the calculation process of the monthly power generation amount,
{18} Voltage V, current I, photovoltaic current IL at a solar radiation intensity of 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{19} A function obtained by differentiating the function Func (V, I, IL, Co, n, Rsh, Rs, T) with a variable V: Div (V, I, IL, Co, n, Rsh, Rs, T) make,
Specifications of {20} solar cells (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )), short circuit current Isca, optimum current Iopa, optimum voltage Vopa, open circuit Select points P1 (0, Isca), P2 (Vopa, Iopa), P3 (Voca, 0) of voltage Voca and any P4 (V4a, I4a) not close to these three points,
{21} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 T of the reference state temperature Ta (298K), the values of the points P1, P2, P3, and P4 Substituting and using IL, Co, n, Rsh, Rs as unknowns: Func (0, Isca, IL, Co, n, Rsh, Rs, Ta) = 0,
Relational expression: Func (Voca, 0, IL, Co, n, Rsh, Rs, Ta) = 0,
Relational expression: Func (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0
Formula: Func (V4a, I4a, IL, Co, n, Rsh, Rs, Ta) = 0
{22} Substituting the value (Vopa, Iopa) of the point P2 of the reference state temperature Ta (298 K) into the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0. , IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, then
{23} The five relational expressions: Func (0, Isca, IL, Co, n, Rsh, Rs, Ta) = 0, Func (Voca, 0, IL, Co, n, Rsh, Rs, Ta) = 0 , Func (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, Div (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, Func (V4a, I4a, IL , Co, n, Rsh, Rs, Ta) = 0, a solution A (ILa, Coa, na, Rsha, Rsa) is calculated by a non-linear solution program.
{24} Similar to the standard state of the solar cell, the short circuit current Iscb is the specification value at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) , Select the point P1 (0, Iscb), P2 (Vopb, Iopb), P3 (Vocb, 0), P4 (V4b, I4b) of the optimal current Iopb, optimal voltage Vopb, open circuit voltage Vocb,
{25} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 and the second temperature Tb (313 K), and the {07} P1, P2, P3, P4 Substituting the values of the points, IL, Co, n, and Rsh are unknown relations: Func (0, Iscb, IL, Co, n, Rsh, Rs, Tb) = 0,
Relational expression: Func (Vocb, 0, IL, Co, n, Rsh, Rs, Tb) = 0,
Relational expression: Func (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0
Formula: Func (V4b, I4b, IL, Co, n, Rsh, Rs, Tb) = 0
{26} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value (Vopb, Iopb) of the {24} point P2 of the second temperature Tb (313K) , And IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, then
{27} The five relational expressions: Func (0, Iscb, IL, Co, n, Rsh, Rs, Tb) = 0, Func (Vocb, 0, IL, Co, n, Rsh, Rs, Tb) = 0 , Func (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, Div (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, Func (V4b, I4b, IL , Co, n, Rsh, Rs, Tb) = 0, a solution A (Ilb, Cob, nb, Rshb, Rsb) is calculated by a nonlinear solution program.
{28} The short circuit current Iscc, which is the specification value at the third solar cell module temperature Tc (328 K (tc = 55 ° C)) and solar radiation intensity Ec (1 kW / m ² )) as in the standard state of the solar cell Select the points P1 (0, Iscc), P2 (Vopc, Iopc), P3 (Vocc, 0), P4 (V4c, I4c) of the optimal current Iopc, optimal voltage Vopc, and open-circuit voltage Vocc,
{29} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 and the third temperature Tc (328 K), the {28} P1, P2, P3, P4 Substituting the value of the point and making IL, Co, n, Rsh, Rs unknowns: Func (0, Iscc, IL, Co, n, Rsh, Rs, Tc) = 0,
Relational expression: Func (Vocc, 0, IL, Co, n, Rsh, Rs, Tc) = 0
Relational expression: Func (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0,
Formula: Func (V4b, I4b, IL, Co, n, Rsh, Rs, Tc) = 0
{30} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value (Vopc, Iopc) of the point P2 of the {28} at the third temperature Tc (328 K) , And IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, then
{31} The five relational expressions: Func (0, Iscc, IL, Co, n, Rsh, Rs, Tc) = 0, Func (Vocc, 0, IL, Co, n, Rsh, Rs, Tc) = 0 , Func (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, Div (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, Func (V4b, I4b, IL , Co, n, Rsh, Rs, Tc) = 0, a solution A (Ilc, Coc, nc, Rshc, Rsc) is calculated by a nonlinear solution program.
{32} Measured solar radiation intensity to be evaluated Ej, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273) and the values of generated voltage Vj−generated current Ij under these conditions,
{33} Solution A (ILa, Coa, na, Rsha, Rsa) of {23} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) at the reference state, the temperature Solution B (ILb, Cob, nb, Rshb, Rsb) of {27} at tb (Celsius: Tb = tb + 273), Solution C (ILc, Coc) of {31} at temperature tc (Celsius: Tc = tc + 273) , nc, Rshc, Rsc) for each (IL, Co, n, Rsh, Rs), curve interpolation is performed for three points, and the characteristic value M (ILm, Com, nm, Rshm, Rsm), then
After correcting {34} ILm by IL'm = Ilm * Ej / Ea by the measured solar radiation intensity Ej, the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( I) (approx. 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or IV curve and PV curve connecting it is created and used. This is a method for evaluating the amount of photovoltaic power generation. Monthly system output coefficient (%) of the target solar power generation system (= (Monthly measured system power generation amount (KWh)) / (Monthly light receiving surface solar radiation amount (KWh / m ² )) / Solar cell rated capacity (KW / KW) / m ² ) * 100)
And in order to calculate the loss (%) due to the temperature rise of the solar cell (= (100−monthly temperature coefficient)), the monthly temperature coefficient (%) (= (monthly calculation system power generation amount (KWh)) / month light receiving surface Monthly calculation system, characterized by calculating solar radiation (KWh / m ² ) / solar cell rated capacity (KW / KW / m ² ) * 100) and evaluating the system output coefficient plus this loss In the IV curve creation method, which is necessary for calculating the amount of generated solar radiation intensity and solar cell temperature during the power generation amount calculation process,
{35} Voltage V, current I, photovoltaic current IL at a solar radiation intensity of 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{36} n points P1 (V1a, I1a), P2 given by the manufacturer in the standard state of the solar cell (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )) (V2a, I2a), P3 (V3a, I3a),... PN (VNa, INa) to the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Create n relational expressions Func (V, I, IL, Co, n, Rsh, Rs, Ta) = 0
{37} Solving Ila, Coa, na, Rsha, Rsa most suitable for the n relational expressions by a mathematical method such as a least squares problem solution,
{38} n points given by the manufacturer at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) as in the standard state of the solar cell P1 (V1b, I1b), P2 (V2b, I2b), P3 (V3b, I3b),... PN (VNb, Inb), and the above relation: Func (V, I, IL, Co, n, Rsh , Rs, T) = 0 and create n relations Func (V, I, IL, Co, n, Rsh, Rs, Tb) = 0
{39} Ilb, Cob, nb, Rshb, Rsb most suitable for the n relational expressions are solved by a mathematical method such as a method of least squares, and then
{40} n points given by the manufacturer at the third solar cell module temperature Tb (328K (tb = 55 ° C)) and solar radiation intensity Eb (1 kW / m ² )) as in the standard state of solar cells P1 (V1c, I1c), P2 (V2c, I2c), P3 (V3c, I3c), ... PN (VNc, Inc), and the above relation: Func (V, I, IL, Co, n, Rsh , Rs, T) = 0 and create n relations Func (V, I, IL, Co, n, Rsh, Rs, Tc) = 0
{41} Solving Ilc, Coc, nc, Rshc, Rsc most suitable for the n relational expressions by a mathematical method such as a least squares problem solution,
{42} Measured solar radiation intensity Ej to be evaluated, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273), and each value of generated voltage Vj−generated current Ij under these conditions,
{43} Solution A (ILa, Coa, na, Rsha, Rsa) of {37} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) at the reference state, the temperature Solution B (ILb, Cob, nb, Rshb, Rsb) of {39} at tb (Celsius: Tb = tb + 273), Solution C (ILc, Coc) of {41} at temperature tc (Celsius: Tc = tc + 273) , nc, Rshc, Rsc) for each (IL, Co, n, Rsh, Rs), curve interpolation is performed for three points, and characteristic value M (ILm, Com, at measured temperature tj (Celsius: Tj = tj + 273)) nm, Rshm, Rsm), then
{44} ILm is corrected by IL'm = Ilm * Ej / Ea based on the measured solar radiation intensity Ej, and then the relation: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. A method for evaluating the amount of photovoltaic power generation. Temperature-corrected system output coefficient (= (actual output (KWh)) / insolation (KWh / m ² ) / solar cell area (m ² ) * for a certain time (about 10 minutes to 1 hour) of the target photovoltaic power generation system (Maximum power at 25 ° C. (Pmax) (KW)) / (Maximum power at measurement temperature (Pmax) (KW))) * (Solar cell rated capacity (KW / KW / m ² )) / Reference solar radiation (KWh / m ² ) (= 1) / Solar cell area (m ² ) * 100) In the calculation of Pmax at 25 ° C. and Pmax at the measurement temperature, solar cell IV having any solar radiation intensity and solar cell temperature As a method of creating a curve, (1) a method of converting an IV curve of a standard solar cell (“practical IV curve creation method”) or (2) a method of solving a solar cell basic equation (“theoretical formula”) I-V curve creation method by) ”) Evaluation method and evaluating the coulometric Temperature-corrected system output coefficient (= (actual output (KWh)) / insolation (KWh / m ² ) / solar cell area (m ² ) * for a certain time (about 10 minutes to 1 hour) of the target photovoltaic power generation system (Maximum power at 25 ° C. (Pmax) (KW)) / (Maximum power at measurement temperature (Pmax) (KW))) * (Solar cell rated capacity (KW / KW / m ² )) / Reference solar radiation (KWh / m ² ) (= 1) / Solar cell area (m ² ) * 100) In the evaluation method characterized by an average value of about 1 to 3 hours, the process of calculating Pmax at 25 ° C. and the measurement temperature In
{45} Voltage V, current I, photovoltaic current IL, solar current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) at 1 kW / m ² of solar radiation intensity Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{46} A function obtained by differentiating the function Func (V, I, IL, Co, n, Rsh, Rs, T) with a variable V: Div (V, I, IL, Co, n, Rsh, Rs, T) make,
{47} Specification values for solar cells (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )), short circuit current Isca, optimum current Iopa, optimum voltage Vopa, open circuit Select point P1 (0, Isca), P2 (Vopa, Iopa), P3 (Voca, 0) of voltage Voca,
{48} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 where T is the reference state temperature Ta (298K), the series resistance Rs is the specification value Rsa at the reference temperature, and Substituting the values of the points of P1, P2, P3 and IL, Co, n, Rsh as unknowns: Func (0, Isca, IL, Co, n, Rsh, Rsa, Ta) = 0,
Relational expression: Func (Voca, 0, IL, Co, n, Rsh, Rsa, Ta) = 0,
Formula: Func (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0
{49} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value Rsa and the value of the point P2 (Vopa , Iopa) and IL, Co, n, Rsh as unknowns,
Create the relation: Div (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0, then
{50} The above four relational expressions: Func (0, Isca, IL, Co, n, Rsh, Rsa, Ta) = 0, Func (Voca, 0, IL, Co, n, Rsh, Rsa, Ta) = 0 , Func (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0, Div (Vopa, Iopa, IL, Co, n, Rsh, Rsa, Ta) = 0 , na, Rsha) is calculated by a nonlinear solution program, then
{51} Similar to the standard state of the solar cell, the short-circuit current Iscb is the specification value at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) , Select points P1 (0, Iscb), P2 (Vopb, Iopb), P3 (Vocb, 0) of the optimal current Iopb, optimal voltage Vopb, open circuit voltage Vocb,
{52} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0, the second temperature Tb (313K) at T, the series resistance Rs, the specification value Rsb at the temperature, and Substituting the values of the points P1, P2, and P3 of {07}, IL, Co, n, and Rsh are unknown relations: Func (0, Iscb, IL, Co, n, Rsh, Rsb, Tb) = 0,
Relational expression: Func (Vocb, 0, IL, Co, n, Rsh, Rsb, Tb) = 0
Formula: Func (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0
{53} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value Rsb at the second temperature and the series resistance Rs of the second temperature Tb (313K) Substituting the value (Vopb, Iopb) at point P2 of {07}, and making IL, Co, n, and Rsh unknown
Create the relation: Div (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0, then
{54} The above four relational expressions: Func (0, Iscb, IL, Co, n, Rsh, Rsb, Tb) = 0, Func (Vocb, 0, IL, Co, n, Rsh, Rsb, Tb) = 0 , Func (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0, Div (Vopb, Iopb, IL, Co, n, Rsh, Rsb, Tb) = 0 satisfying solution A (Ilb, Cob , nb, Rshb) by a non-linear solution program, then
{55} The short circuit current Iscc, which is the specification value at the third solar cell module temperature Tc (328 K (tc = 55 ° C)) and solar radiation intensity Ec (1 kW / m ² )) as in the standard state of the solar cell. Select points P1 (0, Iscc), P2 (Vopc, Iopc), P3 (Vocc, 0) for the optimal current Iopc, optimal voltage Vopc, and open-circuit voltage Vocc,
{56} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 at a third temperature Tc (328K), a series resistance Rs at the specified value Rsc, and Substituting the values of the points P1, P2, and P3 of {55}, IL, Co, n, and Rsh are unknowns: Func (0, Iscc, IL, Co, n, Rsh, Rsc, Tc) = 0,
Relational expression: Func (Vocc, 0, IL, Co, n, Rsh, Rsc, Tc) = 0
Create a relational expression: Func (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0
{57} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the series resistance Rs of the third temperature Tc (328K) has a value Rsc at the third temperature and Substituting the value (Vopc, Iopc) of the point P2 of {55} and making IL, Co, n, Rsh unknown
Create the relation: Div (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0, then
{58} The above four relational expressions: Func (0, Iscc, IL, Co, n, Rsh, Rsc, Tc) = 0, Func (Vocc, 0, IL, Co, n, Rsh, Rsc, Tc) = 0 , Func (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0, Div (Vopc, Iopc, IL, Co, n, Rsh, Rsc, Tc) = 0 satisfying solution A (Ilc, Coc , nc, Rshc) by a non-linear solution program, then
{59} Measured value of solar cell to be evaluated Solar radiation intensity Ej, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273), and each value of generated voltage Vj−generated current Ij under these conditions,
{60} Solution A (ILa, Coa, na, Rsha) of {50} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) in the reference state, the temperature tb ( Celsius: solution B (ILb, Cob, nb, Rshb) of {54} at Tb = tb + 273), solution C (ILc, Coc, nc, Rshc) of {58} at temperature tc (celsius: Tc = tc + 273) ) And curve interpolation at three points for each of the input values Rsa, Rsb, Rsa, Rsc (IL, Co, n, Rsh, Rs), and the characteristic value M at the measured temperature tj (Celsius: Tj = tj + 273) (ILm, Com, nm, Rshm, Rsm) is calculated, then
{61} ILm is corrected by IL'm = Ilm * Ej / Ea based on the measured solar radiation intensity Ej, and then the relationship: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. A method for evaluating the amount of photovoltaic power generation. Temperature-corrected system output coefficient (= (actual output (KWh)) / insolation (KWh / m ² ) / solar cell area (m ² ) * for a certain time (about 10 minutes to 1 hour) of the target photovoltaic power generation system (Maximum power at 25 ° C. (Pmax) (KW)) / (maximum power at measurement temperature (Pmax) (KW)) * (solar cell rated capacity (KW / KW / m ² )) / reference solar radiation (KWh / m ² ) (= 1) / Solar cell area (m ² ) * 100) In the evaluation method characterized by an average value of about 1 to 3 hours, the process of calculating Pmax at 25 ° C. and the measurement temperature In creating the IV curve required for
{62} Voltage V, current I, photovoltaic current IL at a solar radiation intensity of 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{63} A function obtained by differentiating the function Func (V, I, IL, Co, n, Rsh, Rs, T) with a variable V: Div (V, I, IL, Co, n, Rsh, Rs, T) make,
Specifications in {64} solar cells (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )), short circuit current Isca, optimum current Iopa, optimum voltage Vopa, open circuit Select points P1 (0, Isca), P2 (Vopa, Iopa), P3 (Voca, 0) of voltage Voca and any P4 (V4a, I4a) not close to these three points,
{65} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 is set to the reference state temperature Ta (298K) and the values of the points P1, P2, P3, and P4 to T Substituting and using IL, Co, n, Rsh, Rs as unknowns: Func (0, Isca, IL, Co, n, Rsh, Rs, Ta) = 0,
Relational expression: Func (Voca, 0, IL, Co, n, Rsh, Rs, Ta) = 0,
Relational expression: Func (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0
Formula: Func (V4a, I4a, IL, Co, n, Rsh, Rs, Ta) = 0
{66} Substituting the value of the point P2 (Vopa, Iopa) of the reference state temperature Ta (298 K) into the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0 , IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, then
{67} The five relational expressions: Func (0, Isca, IL, Co, n, Rsh, Rs, Ta) = 0, Func (Voca, 0, IL, Co, n, Rsh, Rs, Ta) = 0 , Func (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, Div (Vopa, Iopa, IL, Co, n, Rsh, Rs, Ta) = 0, Func (V4a, I4a, IL , Co, n, Rsh, Rs, Ta) = 0, a solution A (ILa, Coa, na, Rsha, Rsa) is calculated by a non-linear solution program.
{68} Similar to the standard state of the solar cell, the short circuit current Iscb is the specification value at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) , Select the point P1 (0, Iscb), P2 (Vopb, Iopb), P3 (Vocb, 0), P4 (V4b, I4b) of the optimal current Iopb, optimal voltage Vopb, open circuit voltage Vocb,
{69} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0, the second temperature Tb (313K), and the {51} P1, P2, P3, P4 Substituting the values of the points, IL, Co, n, and Rsh are unknown relations: Func (0, Iscb, IL, Co, n, Rsh, Rs, Tb) = 0,
Relational expression: Func (Vocb, 0, IL, Co, n, Rsh, Rs, Tb) = 0,
Relational expression: Func (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0
Formula: Func (V4b, I4b, IL, Co, n, Rsh, Rs, Tb) = 0
{70} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value (Vopb, Iopb) of the {68} point P2 of the second temperature Tb (313K) , And IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, then
{71} The five relational expressions: Func (0, Iscb, IL, Co, n, Rsh, Rs, Tb) = 0, Func (Vocb, 0, IL, Co, n, Rsh, Rs, Tb) = 0 , Func (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, Div (Vopb, Iopb, IL, Co, n, Rsh, Rs, Tb) = 0, Func (V4b, I4b, IL , Co, n, Rsh, Rs, Tb) = 0, a solution A (Ilb, Cob, nb, Rshb, Rsb) is calculated by a nonlinear solution program.
{72} The short circuit current Iscc, which is the specification value at the third solar cell module temperature Tc (328 K (tc = 55 ° C)) and solar radiation intensity Ec (1 kW / m ² )) as in the standard state of the solar cell Select the points P1 (0, Iscc), P2 (Vopc, Iopc), P3 (Vocc, 0), P4 (V4c, I4c) of the optimal current Iopc, optimal voltage Vopc, and open-circuit voltage Vocc,
{73} The function Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 and the third temperature Tc (328 K), the {11} P1, P2, P3, P4 Substituting the value of the point and making IL, Co, n, Rsh, Rs unknowns: Func (0, Iscc, IL, Co, n, Rsh, Rs, Tc) = 0,
Relational expression: Func (Vocc, 0, IL, Co, n, Rsh, Rs, Tc) = 0
Relational expression: Func (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0,
Formula: Func (V4b, I4b, IL, Co, n, Rsh, Rs, Tc) = 0
{74} When the function Div (V, I, IL, Co, n, Rsh, Rs, T) = 0, the value (Vopc, Iopc) of the {72} point P2 at the third temperature Tc (328 K) , And IL, Co, n, Rsh, Rs as unknowns,
Create the relation: Div (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, then
{75} The five relational expressions: Func (0, Iscc, IL, Co, n, Rsh, Rs, Tc) = 0, Func (Vocc, 0, IL, Co, n, Rsh, Rs, Tc) = 0 , Func (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, Div (Vopc, Iopc, IL, Co, n, Rsh, Rs, Tc) = 0, Func (V4b, I4b, IL , Co, n, Rsh, Rs, Tc) = 0, a solution A (Ilc, Coc, nc, Rshc, Rsc) is calculated by a nonlinear solution program.
{76} Measured solar radiation intensity Ej to be evaluated, solar cell module temperature tj (degrees Celsius: absolute temperature Tj = tj + 273), and each value of generated voltage Vj−generated current Ij under these conditions,
{77} Solution A (ILa, Coa, na, Rsha, Rsa) of {67} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) at the reference state, the temperature Solution B (ILb, Cob, nb, Rshb, Rsb) of {71} at tb (Celsius: Tb = tb + 273), Solution C (ILc, Coc) of {75} at temperature tc (Celsius: Tc = tc + 273) , nc, Rshc, Rsc) for each (IL, Co, n, Rsh, Rs), curve interpolation is performed at three points, and the characteristic value M (ILm, Com, at measured temperature tj (Celsius: Tj = tj + 273)) nm, Rshm, Rsm), then
After correcting {78} ILm by IL'm = Ilm * Ej / Ea by the measured solar radiation intensity Ej, the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. A method for evaluating the amount of photovoltaic power generation. System output coefficient after temperature correction (= (actual output (KWh)) / irradiance (KWh / m ² ) / solar cell area (m ² ) * for a certain time (about 10 minutes to 1 hour) of the target photovoltaic power generation system * (Maximum power at 25 ° C. (Pmax) (KW)) / (maximum power at measurement temperature (Pmax) (KW)) * (solar cell rated capacity (KW / KW / m ² )) / reference solar radiation (KWh / m ² ) (= 1) / Solar cell area (m ² ) * 100) In the evaluation method characterized by evaluating for an average value of about 1 to 3 hours, the process of calculating Pmax at 25 ° C. and measurement temperature In creating the IV curve necessary for
{76} Voltage V, current I, photovoltaic current IL at solar intensity 1 kW / m ² , saturation current temperature coefficient Co, junction constant n, parallel resistance Rsh, series resistance Rs, solar cell module temperature T (absolute temperature) Included function: Func (V, I, IL, Co, n, Rsh, Rs, T) = IL-CoT ³ exp (-qEg / nk0T) * (exp (q * (V + Rs * I) / (n * k0 * T)) -1)-(V + Rs * I) / Rsh-I
{77} n points P1 (V1a, I1a), P2 given by the manufacturer in the standard state of the solar cell (module temperature Ta (298K (ta = 25 ° C)), solar radiation intensity Ea (1kW / m ² )) (V2a, I2a), P3 (V3a, I3a),... PN (VNa, INa) to the relational expression: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Create n relational expressions Func (V, I, IL, Co, n, Rsh, Rs, Ta) = 0
{78} Solving Ila, Coa, na, Rsha, Rsa most suitable for the n relational expressions by a mathematical method such as a least squares problem solution,
{79} n points given by the manufacturer at the second solar cell module temperature Tb (313K (tb = 40 ° C)) and solar radiation intensity Eb (1 kW / m ² )) as in the standard state of solar cells P1 (V1b, I1b), P2 (V2b, I2b), P3 (V3b, I3b),... PN (VNb, Inb), and the above relation: Func (V, I, IL, Co, n, Rsh , Rs, T) = 0 and create n relations Func (V, I, IL, Co, n, Rsh, Rs, Tb) = 0
{80} Solving Ilb, Cob, nb, Rshb, Rsb most suitable for the n relational expressions by a mathematical method such as a method of least squares problem,
{81} n points given by the manufacturer at the third solar cell module temperature Tb (328K (tb = 55 ° C)) and solar radiation intensity Eb (1 kW / m ² )) as in the standard state of solar cells P1 (V1c, I1c), P2 (V2c, I2c), P3 (V3c, I3c), ... PN (VNc, Inc), and the above relation: Func (V, I, IL, Co, n, Rsh , Rs, T) = 0 to create n relations Func (V, I, IL, Co, n, Rsh, Rs, Tc) = 0
{82} Solving Ilc, Coc, nc, Rshc, Rsc most suitable for the n relational expressions using a mathematical method such as a least squares problem solution,
{83} Measured solar radiation intensity Ej to be evaluated, solar cell module temperature tj (Celsius: absolute temperature Tj = tj + 273), and each value of generated voltage Vj−generated current Ij under these conditions,
{84} Solution A (ILa, Coa, na, Rsha, Rsa) of {78} at the temperature ta (25 ° C .: absolute temperature Ta (K) = ta (° C.) + 273) at the reference state, the temperature Solution B (ILb, Cob, nb, Rshb, Rsb) of {80} at tb (Celsius: Tb = tb + 273), Solution C (ILc, Coc) of {82} at temperature tc (Celsius: Tc = tc + 273) , nc, Rshc, Rsc) for each (IL, Co, n, Rsh, Rs), curve interpolation is performed for three points, and characteristic value M (ILm, Com, at measured temperature tj (Celsius: Tj = tj + 273)) nm, Rshm, Rsm), then
{85} ILm is corrected by IL'm = Ilm * Ej / Ea based on the measured solar radiation intensity Ej, and then the relationship: Func (V, I, IL, Co, n, Rsh, Rs, T) = 0 Substituting IL'm, Com, nm, Rshm, Rsm for Func (V, I, IL'm, Com, nm, Rshm, Rsm, Tj) = 0, voltage (V)-current ( The relationship of (I) (about 40-50 points) is obtained by a program of nonlinear solution, and the relationship of voltage (V) -current (I) or the IV curve and PV curve connecting it is created and used. A method for evaluating the amount of photovoltaic power generation. The conditions of the data used for evaluation in claims 5, 6, 7, and 8 are (1) solar cell temperature around 25 ° C. and solar radiation intensity of about 850 W / m ² or more, or (2) solar radiation intensity of 1000 W / m ^2.
A method for evaluating the amount of photovoltaic power generation, characterized in that the amount of power generation is evaluated using data or the like in which a stable value of about 1 to 3 hours is obtained.   Recording a processing program to be processed by the photovoltaic power generation evaluation method according to claim 1 or claim 2 or claim 3 or claim 4 or claim 5 or claim 6 or claim 7 or claim 8 or claim 9. A computer-readable recording medium characterized by the above. A solar cell output evaluation apparatus / system comprising a computer capable of operating the recording medium according to claim 10.

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