CN103985060A - Method for calculating photovoltaic power station generating capacity based on light metering data - Google Patents

Abstract

The invention provides a method for calculating photovoltaic power station generating capacity based on light metering data. The method comprises the steps that the generated power of a photovoltaic power station at any time in the whole year is calculated according to radiation data and the environment temperature data minute by minute in the whole year after correction; the generating capacity day by day, the generating capacity month by month and the generating capacity in the whole year of the planned construction photovoltaic power station are calculated. The method achieves calculation of the generating capacity hour by hour, the generating capacity day by day, the generating capacity month by month and the generating capacity in the whole year of the photovoltaic power station. The method has been applied to early stage construction of a plurality of photovoltaic power stations in China, and a foundation is laid for generating capacity and technical and economic assessment in the preliminary work of the photovoltaic power station. Through analysis of the generating capacity characteristics of the photovoltaic power station, a theoretical basis can further be provided for component inclination angle optimization, component distance design, station post-assessment and the like of the photovoltaic power station.

Description

A kind of photovoltaic power station power generation amount computing method based on photometric data

Technical field

The present invention relates to a kind of for calculating the method for generated energy of photovoltaic plant, in conjunction with photovoltaic plant revised whole year by minute radiation data, ambient temperature data; The whole year in each moment of photovoltaic plant, the calculating of day part generated energy are realized.

Background technology

Most of RETScreen, the PVSYST software of adopting of the calculating of the generated energy to photovoltaic plant at present.Due to above-mentioned software do not possess any time photovoltaic plant generated output calculate function; And its algorithm is packed, do not provide the interface of corresponding function yet.Therefore when calculating generated output, the generated energy of photovoltaic plant sometime; While calculating the generated energy of certain day photovoltaic plant, have not yet to see Related Computational Methods.

Summary of the invention

This method at present in the deficiency existing aspect the calculating of photovoltaic power station power generation amount, according to correcting of photovoltaic plant rear whole year by minute radiation data, ambient temperature data, calculated any moment generated output in photovoltaic plant whole year; Calculated plan to build photovoltaic plant day by day, month by month, annual generated energy.

Based on the difference of above-mentioned classic method, this method has adopted following technical scheme:

Photovoltaic power station power generation amount computing method based on photometric data, computing method of the present invention are:

1) light resources data characteristics

Requirement according to " photovoltaic generation engineering feasibility study Report workout way " (trying): the elapsed time sequence data of the on-the-spot solar radiation observation station of project built-up radiation, the temperature etc. by minute sun power of at least continuous a year;

Photovoltaic plant, in previous work, all requires solar radiation observation station is set, and after completing and gathering by the elapsed time sequence data of the built-up radiation of minute sun power, temperature, then according to the historical data of local weather station, carries out whole the ordering of long sequence of data; The Data Source of the inventive method adopt photovoltaic plant correct the rear whole year by minute radiation data, ambient temperature data;

2) solar azimuth calculates

According to spherical astronomy theory, the celestial coordinate system relevant to sun observation is made as following two kinds:

(1) equatorial system of coordinates

Its reference circle is celestial equator, is determined by the axis of rotation of the earth.On coordinate system, the position of the sun is just determined by two coordinates under the line:

1. solar declination δ: the angle of the line of centres of position of sun and celestial equator face, the sun is from the angular distance in equator;

2. solar hour angle ω: meridian circle and by the angle between the secondary circle of sun equator;

(2) horizontal system of coordinates

Its reference circle is horizontal circle, i.e. observer's true horizon; The position of the sun is determined by two coordinates:

1. sun altitude α: the line of observation station and the sun and ground level angle;

2. solar azimuth γ: observer is to the projection of sight line on ground level and the angle of North and South direction of the sun;

(3) selection of the equatorial system of coordinates and the horizontal system of coordinates

This method, in the time carrying out position of sun calculating, adopts the horizontal system of coordinates as the frame of reference, and carries out space coordinate conversion to obtain instant sun altitude and position angle by the equatorial system of coordinates;

The position of the sun is obtained by following spherical formula:

1. solar declination δ:

$\mathrm{\δ}=23.45\sin \left[\frac{\mathrm{\π}}{2}(\frac{{\mathrm{\α}}_1}{N_1}+\frac{{\mathrm{\α}}_2}{N_2}+\frac{{\mathrm{\α}}_3}{N_3}+\frac{{\mathrm{\α}}_4}{N_4})\right]---\left(1\right)$

In formula:

N ₁: 92.975 (number of days of day in the Spring Equinox to summer solstice), α ₁for the number of days calculating since day in the Spring Equinox;

N ₂: 93.629 (number of days of day in summer solstice to the Autumnal Equinox), α ₂for the number of days calculating since the summer solstice;

N ₃: 89.865 (number of days of day in the Autumnal Equinox to winter solstice), α ₃for the number of days calculating since day in the Spring Equinox;

N ₄: 89.012 (number of days of day in winter solstice to the Spring Equinox), α ₄for the number of days calculating since day in the Spring Equinox;

2. sun altitude α:

In formula:

geographic latitude

δ: solar declination

ω: solar hour angle

3. solar hour angle ω:

ω＝15(12-T _h-T _m/60) (3)

In formula:

T _h: hour (true solar time)

T _m: minute (true solar time)

Because domestic worldwide time all adopts Beijing time, can Beijing time be converted into the local true solar time according to following formula;

In formula:

T _solar: the local true solar time

T _st: Beijing time

geographic longitude

E: proofread and correct the time difference, calculated by following formula:

E＝229.2(0.000075+0.001868cosB-0.032077sinB

-0.014615cos2B-0.04089sin2B) (5)

Wherein B is calculated by following formula:

date sequence number in 1 year; (6)

4. solar azimuth γ:

3) the theoretical generated energy of photovoltaic plant

(1) according to solar radiation principle, Q _nsurface level by time theoretical irradiation value comprise direct radiation, scattered radiation; That is:

Q _P＝S _P+D _P (8)

In formula:

Q _p: the built-up radiation (MJ) that surface level receives;

S _p: the direct radiation (MJ) that surface level receives;

D _p: the scattered radiation (MJ) that surface level receives;

The calculating hour amount of scatter radiation proposing according to people such as Erbs and the ratio of built-up radiation can decomposite direct radiation:

$\left\{\begin{array}{c}\frac{D_P}{Q_P}=1.0-0.09k_t,k_t\&le;0.22\\ \frac{D_P}{Q_P}=0.9511-0.1607k_t+4.388k_t^2+16.638k_t^3+12.336k_t^4,0.22<k_t\&le;0.80\\ \frac{D_P}{Q_P}=0.165,k_t>0.80\end{array}\right.---\left(9\right)$

In formula, k _tfor a hour articulation index, it is determined by following formula:

wherein Q _sc: accumulative total built-up radiation (MJ) in residing hour of moment;

(2) and photovoltaic plant for improve generated energy, photovoltaic module is all at a certain angle towards equator; Calculate the solar radiation quantity on photovoltaic module dip plane, adopt Klein method to calculate:

Q _t＝S _t+D _t+R _t (10)

In formula:

Q _t: the built-up radiation (MJ) that dip plane receives;

S _t: the direct radiation (MJ) that dip plane receives

D _t: the scattered radiation (MJ) that dip plane receives;

R _t: the ground return (MJ) that dip plane receives;

Wherein:

S _t＝S _Pcosθ (11)

$D_t=D_P\frac{1+\cos \mathrm{\&beta;}}{2}---\left(12\right)$

$R_t=\mathrm{\&rho;}{Q}_P\frac{1-\cos \mathrm{\&beta;}}{2}---\left(13\right)$

In formula:

β: inclination angle of inclined plane

ρ: earth's surface body surface reflectivity, value is with reference to as follows:

Get arid soil 14%, wet black earth gets 8%, dry ash look ground gets 25～30%, wet grey ground gets 10～12%, hayfield gets 15～25%, wet meadow gets 14～26%, forest gets 4～10%, get 18%, get 9% dry sand damp sand, new snow gets 81%, residual snow gets 46～70%.

The general formula of the solar incident angle cos θ of formula 10 medium dip faces is:

cosθ＝sinαcosβ+cosαsinβcos(γ-γ _s) (14)

In formula:

θ: solar incident angle

β: inclination angle of inclined plane

γ _s: position angle, dip plane

(3) the solar incident angle cos θ of dip plane calculated and obtains according to local latitude, moment etc.; And power station gathers the total solar radiation of surface level in when operation, built-up radiation need be decomposed into after direct radiation and scattered radiation, then according to formula 9～13, obtain the theoretical generated energy of oblique light photovoltaic assembly in conjunction with the device parameter of photovoltaic module;

4) generated energy is proofreaied and correct

Consider the impact of temperature on photovoltaic module generated energy, then proofread and correct out actual generated energy according to the working temperature of photovoltaic module;

G _R＝G _T(1-(T _R-25)co _g) (15)

In formula:

G _r: dip plane correction calculation generated energy (kWh)

G _t: dip plane is theoretical calculates generated energy (not considering temperature factor) (kWh)

T _r: photovoltaic module surface temperature (DEG C)

Co _g: photovoltaic module temperature coefficient (%/DEG C)

But photovoltaic plant is carrying out, in previous work, being only provided with radiation station in site; Lack the measurement to photovoltaic module surface temperature; Consider that the packet of radiation station collection is containing the environment temperature sequence of complete sequence; Therefore, environment temperature need to be corrected to the surface temperature into photovoltaic module;

$T_R=\frac{Q_P\&times;(\mathrm{NOCT}-20)}{800}+T_{\mathrm{amb}}---\left(16\right)$

In formula:

NOCT: photovoltaic module nominal operation temperature (DEG C)

T _amb: environment temperature (DEG C)

5) generated energy output

Can export and plan to build any moment generated output in photovoltaic plant whole year according to said method, thereby also obtain the generated energy of corresponding period; By the calculating to each moment generated energy whole year, can complete photovoltaic plant day by day, month by month, annual generated energy.

The invention has the beneficial effects as follows, this method be photovoltaic plant by time, day by day, month by month, the calculating of annual generated energy.

This method has been applied to domestic multiple photovoltaic plant and has built early stage, for generated energy, technological economics evaluation in photovoltaic plant previous work provide the foundation.By analyzing the generated energy characteristic of photovoltaic plant, the assembly inclination angle that also can be photovoltaic plant is optimized, assess after the design of inter-module distance, power station etc. provided fundamental basis.

Brief description of the drawings

Fig. 1 is calculation flow chart of the present invention.

Embodiment

Below by concrete embodiment, also the present invention is described in further detail by reference to the accompanying drawings.

Photovoltaic power station power generation amount computing method based on photometric data, calculation procedure of the present invention is:

1) light resources data characteristics

Photovoltaic plant, in previous work, all requires solar radiation observation station is set, and after completing and gathering by the elapsed time sequence data of the built-up radiation of minute sun power, temperature, then according to the historical data of local weather station, carries out whole the ordering of long sequence of data; The Data Source of the inventive method adopt photovoltaic plant correct the rear whole year by minute radiation data, ambient temperature data;

2) solar azimuth calculates

According to spherical astronomy theory, the celestial coordinate system relevant to sun observation is made as following two kinds:

(1) equatorial system of coordinates

Its reference circle is celestial equator, is determined by the axis of rotation of the earth.On coordinate system, the position of the sun is just determined by two coordinates under the line:

1. solar declination δ: the angle of the line of centres of position of sun and celestial equator face, the sun is from the angular distance in equator;

2. solar hour angle ω: meridian circle and by the angle between the secondary circle of sun equator;

(2) horizontal system of coordinates

Its reference circle is horizontal circle, i.e. observer's true horizon; The position of the sun is determined by two coordinates:

1. sun altitude α: the line of observation station and the sun and ground level angle;

2. solar azimuth γ: observer is to the projection of sight line on ground level and the angle of North and South direction of the sun;

(3) selection of the equatorial system of coordinates and the horizontal system of coordinates

This method, in the time carrying out position of sun calculating, adopts the horizontal system of coordinates as the frame of reference, and carries out space coordinate conversion to obtain instant sun altitude and position angle by the equatorial system of coordinates;

The position of the sun is obtained by following spherical formula:

1. solar declination δ:

$\mathrm{\&delta;}=23.45\sin \left[\frac{\mathrm{\&pi;}}{2}(\frac{{\mathrm{\&alpha;}}_1}{N_1}+\frac{{\mathrm{\&alpha;}}_2}{N_2}+\frac{{\mathrm{\&alpha;}}_3}{N_3}+\frac{{\mathrm{\&alpha;}}_4}{N_4})\right]---\left(1\right)$

In formula:

N ₁: 92.975 (number of days of day in the Spring Equinox to summer solstice), α ₁for the number of days calculating since day in the Spring Equinox;

N ₂: 93.629 (number of days of day in summer solstice to the Autumnal Equinox), α ₂for the number of days calculating since the summer solstice;

N ₃: 89.865 (number of days of day in the Autumnal Equinox to winter solstice), α ₃for the number of days calculating since day in the Spring Equinox;

N ₄: 89.012 (number of days of day in winter solstice to the Spring Equinox), α ₄for the number of days calculating since day in the Spring Equinox;

2. sun altitude α:

In formula:

geographic latitude

δ: solar declination

ω: solar hour angle

3. solar hour angle ω:

ω＝15(12-T _h-T _m/60) (3)

In formula:

T _h: hour (true solar time)

T _m: minute (true solar time)

Because domestic worldwide time all adopts Beijing time, can Beijing time be converted into the local true solar time according to following formula;

In formula:

T _solar: the local true solar time

T _st: Beijing time

geographic longitude

E: proofread and correct the time difference, calculated by following formula:

E＝229.2(0.000075+0.001868cosB-0.032077sinB

-0.014615cos2B-0.04089sin2B) (5)

Wherein B is calculated by following formula:

date sequence number in 1 year; (6)

4. solar azimuth γ:

3) the theoretical generated energy of photovoltaic plant

(1) according to solar radiation principle, Q _nsurface level by time theoretical irradiation value comprise direct radiation, scattered radiation; That is:

Q _P＝S _P+D _P (8)

In formula:

Q _p: the built-up radiation (MJ) that surface level receives;

S _p: the direct radiation (MJ) that surface level receives;

D _p: the scattered radiation (MJ) that surface level receives;

The calculating hour amount of scatter radiation proposing according to people such as Erbs and the ratio of built-up radiation can decomposite direct radiation:

$\left\{\begin{array}{c}\frac{D_P}{Q_P}=1.0-0.09k_t,k_t\&le;0.22\\ \frac{D_P}{Q_P}=0.9511-0.1607k_t+4.388k_t^2+16.638k_t^3+12.336k_t^4,0.22<k_t\&le;0.80\\ \frac{D_P}{Q_P}=0.165,k_t>0.80\end{array}\right.---\left(9\right)$

In formula, k _tfor a hour articulation index, it is determined by following formula:

wherein Q _sc: accumulative total built-up radiation (MJ) in residing hour of moment;

(2) and photovoltaic plant for improve generated energy, photovoltaic module is all at a certain angle towards equator; Calculate the solar radiation quantity on photovoltaic module dip plane, adopt Klein method to calculate:

Q _t＝S _t+D _t+R _t (10)

In formula:

Q _t: the built-up radiation (MJ) that dip plane receives;

S _t: the direct radiation (MJ) that dip plane receives

D _t: the scattered radiation (MJ) that dip plane receives;

R _t: the ground return (MJ) that dip plane receives;

Wherein:

S _t＝S _Pcosθ (11)

$D_t=D_P\frac{1+\cos \mathrm{\&beta;}}{2}---\left(12\right)$

$R_t=\mathrm{\&rho;}{Q}_P\frac{1-\cos \mathrm{\&beta;}}{2}---\left(13\right)$

In formula:

β: inclination angle of inclined plane

ρ: earth's surface body surface reflectivity, value is with reference to as follows:

Get arid soil 14%, wet black earth gets 8%, dry ash look ground gets 25～30%, wet grey ground gets 10～12%, hayfield gets 15～25%, wet meadow gets 14～26%, forest gets 4～10%, get 18%, get 9% dry sand damp sand, new snow gets 81%, residual snow gets 46～70%.

The general formula of the solar incident angle cos θ of formula 10 medium dip faces is:

cosθ＝sinαcosβ+cosαsinβcos(γ-γ _s) (14)

In formula:

θ: solar incident angle

β: inclination angle of inclined plane

γ s: position angle, dip plane

(3) the solar incident angle cos θ of dip plane calculated and obtains according to local latitude, moment etc.; And power station gathers the total solar radiation of surface level in when operation, built-up radiation need be decomposed into after direct radiation and scattered radiation, then according to formula 9～13, obtain the theoretical generated energy of oblique light photovoltaic assembly in conjunction with the device parameter of photovoltaic module;

4) generated energy is proofreaied and correct

Consider the impact of temperature on photovoltaic module generated energy, then proofread and correct out actual generated energy according to the working temperature of photovoltaic module;

G _R＝G _T(1-(T _R-25)co _g) (15)

In formula:

G _r: dip plane correction calculation generated energy (kWh)

G _t: dip plane is theoretical calculates generated energy (not considering temperature factor) (kWh)

T _r: photovoltaic module surface temperature (DEG C)

Co _g: photovoltaic module temperature coefficient (%/DEG C)

But photovoltaic plant is carrying out, in previous work, being only provided with radiation station in site; Lack the measurement to photovoltaic module surface temperature; Consider that the packet of radiation station collection is containing the environment temperature sequence of complete sequence; Therefore, environment temperature need to be corrected to the surface temperature into photovoltaic module;

$T_R=\frac{Q_P\&times;(\mathrm{NOCT}-20)}{800}+T_{\mathrm{amb}}---\left(16\right)$

In formula:

NOCT: photovoltaic module nominal operation temperature (DEG C)

T _amb: environment temperature (DEG C)

5) generated energy output

Can export and plan to build any moment generated output in photovoltaic plant whole year according to said method, thereby also obtain the generated energy of corresponding period; By the calculating to each moment generated energy whole year, can complete photovoltaic plant day by day, month by month, annual generated energy.

The present invention is summarized as follows:

The photovoltaic power station power generation amount computing method based on measured data of the present embodiment are that the following measured data by gathering photovoltaic plant realizes:

1) the residing latitude of photovoltaic plant;

2) the revised whole year by minute radiation data, ambient temperature data;

The technical matters that the present invention mainly solves is:

1) calculate plan to build photovoltaic plant whole year by minute generated energy;

2) calculate the generated energy of planning to build the annual arbitrary period of photovoltaic plant;

According to above-mentioned design, the photovoltaic power station power generation amount based on photometric data of the present embodiment is calculated, and step is described below:

1) utilize formula 1～7 calculate annual by minute solar declination, hour angle, elevation angle, position angle;

2) extract built-up radiation Value Data, calculate annual by a hour accumulative total built-up radiation.First according to formula 8, formula 9, built-up radiation is decomposed; Calculate respectively oblique light photovoltaic assembly theory by a minute generated energy according to formula 10～14 again;

3) extraction environment temperature, calculates photovoltaic module surface temperature according to the built-up radiation value in corresponding moment according to formula 16;

4) integrating step 3, the photovoltaic module theory that step 2 is calculated is proofreaied and correct according to formula 15 by minute generated energy;

5) generated energy of the annual day part of output photovoltaic plant

This method has been applied to domestic multiple photovoltaic plant and has built early stage, for the basis providing is provided in photovoltaic plant previous work.By analyzing the generated energy characteristic of photovoltaic plant, the assembly inclination angle that also can be photovoltaic plant is optimized, assess after the design of inter-module distance, power station etc. provided fundamental basis.

Claims (1)

1. the photovoltaic power station power generation amount computing method based on photometric data, is characterized in that, calculation procedure is:

1) light resources data characteristics

Data Source adopt photovoltaic plant correct the rear whole year by minute radiation data, ambient temperature data;

2) solar azimuth calculates

According to spherical astronomy theory, the celestial coordinate system relevant to sun observation is made as following two kinds:

(1) equatorial system of coordinates

Its reference circle is celestial equator, is determined by the axis of rotation of the earth; On coordinate system, the position of the sun is just determined by two coordinates under the line:

1. solar declination δ: the angle of the line of centres of position of sun and celestial equator face, the sun is from the angular distance in equator;

2. solar hour angle ω: meridian circle and by the angle between the secondary circle of sun equator;

(2) horizontal system of coordinates

Its reference circle is horizontal circle, i.e. observer's true horizon; The position of the sun is determined by two coordinates:

1. sun altitude α: the line of observation station and the sun and ground level angle;

2. solar azimuth γ: observer is to the projection of sight line on ground level and the angle of North and South direction of the sun;

(3) selection of the equatorial system of coordinates and the horizontal system of coordinates

This method, in the time carrying out position of sun calculating, adopts the horizontal system of coordinates as the frame of reference, and carries out space coordinate conversion to obtain instant sun altitude and position angle by the equatorial system of coordinates;

The position of the sun is obtained by following spherical formula:

1. solar declination δ:

In formula:

N ₁: 92.975 (number of days of day in the Spring Equinox to summer solstice), α ₁for the number of days calculating since day in the Spring Equinox;

N ₂: 93.629 (number of days of day in summer solstice to the Autumnal Equinox), α ₂for the number of days calculating since the summer solstice;

N ₃: 89.865 (number of days of day in the Autumnal Equinox to winter solstice), α ₃for the number of days calculating since day in the Spring Equinox;

N ₄: 89.012 (number of days of day in winter solstice to the Spring Equinox), α ₄for the number of days calculating since day in the Spring Equinox;

2. sun altitude α:

in formula:

geographic latitude

δ: solar declination

ω: solar hour angle

3. solar hour angle ω:

ω＝15(12-T _h-T _m/60) (3)

In formula:

T _h: hour be the true solar time

T _m: minute be the true solar time

Because domestic worldwide time all adopts Beijing time, can Beijing time be converted into the local true solar time according to following formula;

In formula:

T _solar: the local true solar time

T _st: Beijing time

geographic longitude

E: proofread and correct the time difference, calculated by following formula:

E＝229.2(0.000075+0.001868cosB-0.032077sinB

-0.014615cos2B-0.04089sin2B) (5)

Wherein B is calculated by following formula:

n: the date sequence number in a year; (6)

4. solar azimuth γ:

3) the theoretical generated energy of photovoltaic plant

(1) according to solar radiation principle, Q _nsurface level by time theoretical irradiation value comprise direct radiation, scattered radiation; That is:

Q _P＝S _P+D _P (8)

Q _p: the built-up radiation (MJ) that surface level receives;

S _p: the direct radiation (MJ) that surface level receives;

D _p: the scattered radiation (MJ) that surface level receives;

The calculating hour amount of scatter radiation proposing according to people such as Erbs and the ratio of built-up radiation can decomposite direct radiation:

In formula, k _tfor a hour articulation index, it is determined by following formula:

wherein Q _sc: accumulative total built-up radiation (MJ) in residing hour of moment;

(2) and photovoltaic plant for improve generated energy, photovoltaic module is all at a certain angle towards equator; Calculate the solar radiation quantity on photovoltaic module dip plane, adopt Klein method to calculate:

Q _t＝S _t+D _t+R _t (10)

In formula:

Q _t: the built-up radiation (MJ) that dip plane receives;

S _t: the direct radiation (MJ) that dip plane receives

D _t: the scattered radiation (MJ) that dip plane receives;

R _t: the ground return (MJ) that dip plane receives;

Wherein:

S _t＝S _Pcosθ (11)

In formula:

β: inclination angle of inclined plane

ρ: earth's surface body surface reflectivity, value is as follows:

Get arid soil 14%, wet black earth gets 8%, dry ash look ground gets 25～30%, wet grey ground gets 10～12%, hayfield gets 15～25%, wet meadow gets 14～26%, forest gets 4～10%, get 18%, get 9% dry sand damp sand, new snow gets 81%, residual snow gets 46～70%;

The general formula of the solar incident angle cos θ of formula 10 medium dip faces is:

cosθ＝sinαcosβ+cosαsinβcos(γ-γ _s) (14)

In formula:

θ: solar incident angle

β: inclination angle of inclined plane

γ _s: position angle, dip plane

(3) the solar incident angle cos θ of dip plane calculated and obtains according to local latitude, moment; And power station gathers the total solar radiation of surface level in when operation, built-up radiation need be decomposed into after direct radiation and scattered radiation, then according to formula 9～13, obtain the theoretical generated energy of oblique light photovoltaic assembly in conjunction with the device parameter of photovoltaic module;

4) generated energy is proofreaied and correct

Consider the impact of temperature on photovoltaic module generated energy, then proofread and correct out actual generated energy according to the working temperature of photovoltaic module;

G _R＝G _T(1-(T _R-25)co _g) (15)

In formula:

G _r: dip plane correction calculation generated energy (kWh)

G _t: the theoretical generated energy (kWh) that calculates in dip plane

T _r: photovoltaic module surface temperature (DEG C)

Co _g: photovoltaic module temperature coefficient (%/DEG C)

But photovoltaic plant is carrying out, in previous work, being only provided with radiation station in site; Lack the measurement to photovoltaic module surface temperature; Consider that the packet of radiation station collection is containing the environment temperature sequence of complete sequence; Therefore, environment temperature need to be corrected to the surface temperature into photovoltaic module;

In formula:

NOCT: photovoltaic module nominal operation temperature (DEG C)

T _amb: environment temperature (DEG C)

5) generated energy output

Can export and plan to build any moment generated output in photovoltaic plant whole year according to said method, thereby also obtain the generated energy of corresponding period; By the calculating to each moment generated energy whole year, can complete photovoltaic plant day by day, month by month, annual generated energy.