CN107577844A - A method and system for predicting the outlet temperature of the mirror field of a trough-type photothermal power station - Google Patents

Abstract

The present invention proposes a method and system for predicting the outlet temperature of the mirror field of a trough-type photothermal power station. The actual operating parameters of the thermal power station are substituted into the pre-established temperature prediction model to determine the actual value of the optical efficiency of the collector; according to the temperature prediction model, the actual value of the optical efficiency of the collector and the predicted value of the direct solar radiation intensity in the time period to be predicted, determine Predicted value of outlet temperature of mirror field in trough solar thermal power plant. The prediction method and system provided by the invention can accurately predict the outlet temperature of the mirror field within a certain period of time in the future; it is of great significance for timely adjusting and controlling the tracking angle of the concentrator and preventing the heat transfer oil in the heat collecting tube from overheating and cracking.

Description

A method and system for predicting the outlet temperature of the mirror field of a trough-type photothermal power station

technical field

The invention relates to the technical field of power station automation control, in particular to a method and system for predicting the outlet temperature of a mirror field of a trough-type photothermal power station.

Background technique

The trough mirror field is the energy collection part of the trough solar thermal power station. The trough mirror field mainly includes several parallel trough circuits. Each trough circuit is mainly composed of several heat collectors. The heat collector mainly includes heat collectors. Core components such as collector brackets, heat collector tubes, reflectors, and tracking control systems. The trough photothermal power generation uses a parabolic concentrator to focus the direct sunlight radiation to heat the heat transfer fluid in the heat collector tube. The commonly used heat transfer fluid is heat transfer oil, which can be heated up to 400°C. The heat transfer oil is heated to a high temperature state for use in Generate steam to drive the steam turbine to generate electricity. The temperature of the heat transfer oil at the outlet of the mirror field of the trough solar thermal power station is also called the outlet temperature of the mirror field of the trough solar thermal power station.

The outlet temperature of the mirror field of the trough solar thermal power station is determined by many factors, including the intensity of solar radiation, the ambient temperature of the site, the wind speed and the flow rate of heat transfer oil, etc. During the power generation process of the trough solar thermal power plant, the above factors will change at any time. If the flow of heat transfer oil flowing in the heat collecting tube is not controlled in time, the temperature at the outlet of the mirror field will be too high, which will lead to cracking of the heat transfer oil, which will affect the power of the solar thermal power plant. Related equipment will cause damage, and in severe cases, it may cause production accidents. For this reason, accurately predicting the outlet temperature of the mirror field of the trough-type solar thermal power station and timely adjusting the flow rate of heat transfer oil play a very important role in the optimal control of the trough-type solar thermal power station. It has also become an urgent problem for those skilled in the art.

Contents of the invention

In order to solve the defect that the exit temperature of the mirror field of the trough-type photothermal power station cannot be accurately predicted in the prior art, the purpose of the present invention is to propose a method for predicting the outlet temperature of the mirror field of the trough-type photothermal power station. The method is through the following technical scheme Achieved:

Obtain the actual operating parameters of the trough solar thermal power plant in the preset time period;

Substituting the actual operating parameters of the trough solar thermal power plant in the preset time period into the pre-established temperature prediction model to determine the actual value of the optical efficiency of the collector;

According to the temperature prediction model, the actual value of the optical efficiency of the collector and the predicted value of the solar direct radiation intensity in the time period to be predicted, the predicted value of the outlet temperature of the mirror field of the trough solar thermal power station is determined.

Further, substituting the actual operating parameters of the trough-type photothermal power plant in the preset time period into the temperature prediction model to determine the actual value of the optical efficiency of the collector, including:

Substituting the actual operating parameters of the trough solar thermal power plant in the preset time period into the temperature prediction model of the following formula:

In the formula, the actual operating parameters include: the inlet temperature T _in of the trough loop at the preset start time, the actual temperature T _out of the trough loop outlet at the preset end time, the average temperature T _m of the heat transfer fluid, and the preset start, The average value of the relevant parameters at the end time; the average value of the relevant parameters at the preset start and end time includes the average value of the mass flow rate of the heat transfer fluid The average specific heat capacity c _f of the heat transfer fluid, the average heat collection area of the trough loop A _a , the average heat dissipation of the collector Q _loss , the average heat dissipation of the pipe connected to the collector Q _loss,pipe and the heat dissipation of the trough loop Melting average value C _loop ;

η is the actual value of the optical efficiency of the collector; K _θb (θ) is the incident angle function of direct solar radiation; G _e is the intensity of direct solar radiation; T _m = (T _out +T _in )/2;

Calculate the actual value η of the optical efficiency of the heat collector according to the temperature prediction model.

Further, according to the temperature prediction model, the actual value of the optical efficiency of the collector, and the predicted value of the direct solar radiation intensity in the time period to be predicted, the determination of the predicted value of the outlet temperature of the mirror field of the trough-type photothermal power station includes:

Substitute the actual value of the optical efficiency of the collector into the temperature prediction model;

Calculate the predicted value T _{out,cal of} the outlet temperature of the mirror field of the trough solar thermal power station through the temperature prediction model, as follows:

In the formula, G _e,cal is the predicted value of direct solar radiation intensity in the time period to be predicted; T _in,real is the inlet temperature of the trough circuit at the current moment.

Another object of the present invention is to propose a system for predicting the outlet temperature of the mirror field of a trough-type photothermal power station, including:

The acquisition module acquires the actual operating parameters of the trough solar thermal power plant in the preset time period;

A calculation module, substituting the actual operating parameters of the trough solar thermal power plant in the preset time period into the pre-established temperature prediction model to determine the actual value of the optical efficiency of the collector;

The prediction module, according to the temperature prediction model, the actual value of the optical efficiency of the collector, and the predicted value of the direct solar radiation intensity in the time period to be predicted, determines the predicted value of the outlet temperature of the mirror field of the trough-type photothermal power station;

The modeling module is used for establishing and storing a temperature prediction model in advance.

Compared with the closest prior art, the technical solution provided by the present invention has the following beneficial effects:

The invention provides a method and system for predicting the outlet temperature of the mirror field of a trough-type photothermal power station. First, the actual value of the optical efficiency of the collector for a preset time period is determined according to the temperature prediction model, and then the actual value of the optical efficiency of the collector is determined according to the temperature prediction model and the optical efficiency of the collector. The actual value of the efficiency determines the predicted value of the exit temperature of the mirror field of the trough solar thermal power station, and the temperature prediction model is constructed according to the pre-acquired solar direct radiation intensity and the actual operating parameters of the trough solar thermal power plant. Compared with the method of obtaining the estimated optical efficiency with the minimum variance in the prior art, and then predicting the subsequent loop outlet temperature based on the value, the prediction method and system of the present invention can more accurately predict the mirror field of the trough-type photothermal power station The outlet temperature realizes the accurate prediction of the outlet temperature of the mirror field of the trough solar thermal power plant in the future, ensuring the safe and reliable operation of the trough solar thermal power plant.

Description of drawings

Fig. 1 is a schematic flowchart of a method for predicting the outlet temperature of a mirror field of a trough-type solar-thermal power plant in an embodiment of the present invention.

Fig. 2 is a source diagram of pre-collected data in an embodiment of the present invention;

Fig. 3 is the direct solar radiation DNI distribution figure in the embodiment of the present invention;

Fig. 4 is a comparison chart of the predicted value of the outlet temperature obtained by the method in the embodiment of the present invention and the measured value.

Detailed ways

In order to better understand the present invention, the content of the present invention will be further described below in conjunction with the accompanying drawings and examples.

The method for predicting the outlet temperature of the mirror field of the trough-type solar thermal power station in the embodiment of the present invention can accurately predict the outlet temperature of the mirror field of the trough-type solar-thermal power station in a short period of time. When the outlet temperature is found to exceed the preset threshold, the system can be alerted The mass flow rate of the heat transfer fluid is adjusted automatically or manually by on-site operators to prevent the overheating and cracking of the heat transfer oil in the heat collecting tube from affecting the safe operation of the trough solar thermal power plant.

The trough-type photothermal power station involved in the present invention is composed of a large number of trough-type circuits connected in parallel. The flow rate of the heat transfer fluid in each circuit is basically the same, and the outlet temperature of each trough-type circuit is also consistent during normal operation. Therefore, each tank The outlet temperature of the loop is the outlet temperature of the mirror field of the trough solar thermal power plant. The method of the present invention needs to be based on the data collected by the solar radiation monitoring station, weather station, and trough mirror field operation monitoring station as shown in Figure 2 to predict the exit of the mirror field of the trough photothermal power station temperature.

The specific flow chart of the method for predicting the outlet temperature of the mirror field of the trough-type photothermal power station in the embodiment of the present invention is shown in Figure 1, which includes the following steps:

Step S101, obtaining the actual operating parameters of the trough solar thermal power plant in the preset time period;

Step S102, substituting the actual operating parameters of the trough solar thermal power plant in the preset time period into the pre-established temperature prediction model to determine the actual value of the optical efficiency of the collector;

Step S103, according to the temperature prediction model, the actual value of the optical efficiency of the collector, and the predicted value of the solar direct radiation intensity in the time period to be predicted, determine the predicted value of the outlet temperature of the mirror field of the trough-type photothermal power station.

In the above step S101, the acquisition of the actual operating parameters of the trough-type solar thermal power plant in the preset time period includes:

The inlet temperature T _in of the trough circuit at the preset start time (unit ℃), the actual temperature T _out of the trough circuit outlet at the preset end time moment (unit ℃), the average temperature T _m of the heat transfer fluid (unit ℃) and the preset Set the average value of the relevant parameters at the start and end time; the average value of the relevant parameters at the preset start and end time include the average value of the mass flow rate of the heat transfer fluid (unit: kg/s), average specific heat capacity of heat transfer fluid c _f (unit: J/(kg·℃)), average value of heat collecting area of trough circuit A _a (unit: m ² ), average value of heat dissipation of heat collector Q _loss , the average heat dissipation Q _loss,pipe of the pipe connected to the collector and the average value C _loop of the thermal melt of the trough circuit (unit J/°C).

In the above step S102, substituting the actual operating parameters of the trough solar thermal power plant in the preset time period into the pre-established temperature prediction model to determine the actual value of the optical efficiency of the collector may include the following steps:

Substituting the actual operating parameters of the trough solar thermal power plant in the preset time period into the temperature prediction model of the following formula:

For the daily operation of the trough concentrator, its optical performance changes with time, but it is relatively stable in the short term. Based on the short-term actual operation data, the above formula (1) is transformed into the following formula (2), through the formula (2) Calculate the actual value of the optical efficiency of the collector:

In the formula, T _m = (T _out +T _in )/2;

η is the actual value of the optical efficiency of the collector. For trough solar thermal power plants, this efficiency covers the specular reflectance of the concentrator reflector, cleanliness, transmittance, absorptivity, surface cleanliness and other parameters of the collector tube;

K _θb (θ) is the incident angle function of direct solar radiation, and for trough solar thermal power plants, it is the incident angle function related to the normal direct radiation DNI;

G _e is the direct solar radiation intensity DNI, as shown in Figure 3 is the DNI distribution map.

Based on the short-term actual operation data, the actual value η of the optical efficiency of the collector is calculated according to the formula (1), and the outlet temperature of the mirror field in the subsequent period of time can be predicted according to the above temperature prediction model. The short time referred to in the embodiments of the present invention generally refers to predicting the outlet temperature of the mirror field of the trough-type solar-thermal power station within 5 minutes, and the preset time of the actual operating parameters of the trough-type solar-thermal power station that needs to be collected can be within 30 minutes. parameters are appropriate.

K _θb (θ) in the above formulas (1) and (2) can be calculated as follows:

In the formula, θ is the average value of the incident angle of the direct solar radiation DNI at the preset start and end time, unit °; IAM is the incident angle correction coefficient; f is the focal length of the collector, unit m; L is the length of the collector , unit m.

The IAM in the above formula (3) can be calculated as follows:

The Q _loss in the above formulas (1) and (2) can be calculated as follows:

In the formula, θ is the average value of the incident angle of the direct solar radiation DNI at the preset starting and ending moments; IAM is the incident angle correction coefficient, and the calculation method is the same as formula (3); _Vw is the environment at the preset starting and ending moments The average wind speed, in m/s; T _a is the average ambient temperature at the preset start and end time, in °C; A ₀ ~ A ₆ is the calculation coefficient of the heat dissipation of the heat collecting tube, which can be selected from the following table 1 Any set of data, the two sets of data are parameters fitted by two experimental methods, and the values are roughly similar.

Table 1 Calculation coefficient of heat dissipation of heat collecting tube

The Q _loss,pipe in the above formulas (1) and (2) can be calculated as follows:

In the formula, D _o is the outer diameter of the pipe connected to the heat collector wrapped with insulation material, in m; D _i is the inner diameter of the pipe connected to the heat collector, in m; λ is the thermal conductivity of the heat insulation material, in W/( m °C); α is the surface heat transfer coefficient of the pipe connected to the collector, unit W/(m ² °C), Where ω is the average ambient wind speed at the preset start and end times, and α generally takes a value of 11.63W/(m ² °C); T _a1 is the outer surface of the pipe connected to the collector at the preset start and end time The average temperature, in ℃; T _a2 is the average ambient temperature at the preset start and end time, in ℃.

In the above step S102, according to the temperature prediction model and the actual value of the optical efficiency of the collector, the predicted value of the outlet temperature of the mirror field of the trough-type photothermal power station can be determined, which may include the following steps:

Substitute the actual value of the optical efficiency of the collector into the temperature prediction model;

Calculate the predicted value T _{out,cal of} the outlet temperature of the mirror field of the trough solar thermal power station through the temperature prediction model, as follows:

In the formula, G _e,cal is the predicted value of direct solar radiation intensity in the time period to be predicted; T _in,real is the inlet temperature of the trough circuit at the current moment, and the other parameters are the same as those in formula (1).

G _{e, cal} can be predicted using existing technologies known to those skilled in the art, for example: the result of fitting the data of the same period of history and comparable weather conditions as the predicted value, or according to the application number CN201710103508.8 The solar direct radiation intensity information prediction method and system predict the solar direct radiation intensity in the future.

In order to verify the accuracy of a method for predicting the outlet temperature of the mirror field of a trough-type solar-thermal power station provided by the embodiment of the present invention, starting from 10 o'clock, the experimental data of the first 15 minutes were calculated to obtain the actual value of the optical efficiency of the trough-type circuit, as shown in As shown in Figure 4, the predicted outlet temperature of the circuit heat transfer oil is generally consistent with the measured outlet temperature trend. The maximum deviation appeared at 10:30, reaching 4.86°C, and lasted for about 3 minutes. After that, the prediction deviation gradually decreased, and the average deviation during the test was 1.07°C. It can be seen that the method for predicting the outlet temperature of the mirror field of the trough-type photothermal power station provided by the embodiment of the present invention can predict the outlet temperature of the mirror field more accurately.

Based on the same inventive concept, the embodiment of the present invention also provides a prediction system for the outlet temperature of the mirror field of the trough-type photothermal power station. The prediction system for the outlet temperature of the mirror field of the trough-type photothermal power station mainly includes an acquisition module, a construction module, a calculation module and a prediction module. The functions of the above four modules are further described below:

The acquisition module acquires the actual operating parameters of the trough solar thermal power plant in the preset time period;

A calculation module, substituting the actual operating parameters of the trough solar thermal power plant in the preset time period into the pre-established temperature prediction model to determine the actual value of the optical efficiency of the collector;

The prediction module, according to the temperature prediction model, the actual value of the optical efficiency of the collector, and the predicted value of the direct solar radiation intensity in the time period to be predicted, determines the predicted value of the outlet temperature of the mirror field of the trough-type photothermal power station;

The modeling module is used for establishing and storing a temperature prediction model in advance.

The acquisition module obtains the actual operating parameters of the trough solar thermal power plant in the preset time period, which may include:

The inlet temperature T _in of the trough circuit at the preset start time, the actual temperature T _out of the trough circuit outlet at the preset end time, the average temperature T _m of the heat transfer fluid, and the average value of relevant parameters at the preset start and end time; The average value of the relevant parameters at the preset start and end time includes the average value of the mass flow rate of the heat transfer fluid The average specific heat capacity c _f of the heat transfer fluid, the average heat collection area of the trough loop A _a , the average heat dissipation of the collector Q _loss , the average heat dissipation of the pipe connected to the collector Q _loss,pipe and the heat dissipation of the trough loop Melting average C _loop .

The modeling module can be used to build a temperature prediction model as follows:

In the formula, η is the actual value of the optical efficiency of the collector; K _θb (θ) is the incident angle function of direct solar radiation; G _e is the intensity of direct solar radiation; T _m =(T _out +T _in )/2.

The calculation module can be used for substituting the actual operating parameters of the trough solar thermal power plant in the preset time period into the temperature prediction model of the above formula, and calculating the actual value of the optical efficiency of the heat collector.

The Q _loss in the temperature prediction model can be calculated by the calculation module as follows:

In the formula, θ is the average value of the incident angle of direct solar radiation at the preset start and end time; IAM is the correction coefficient of the incident angle; V _w is the average value of the ambient wind speed at the preset start and end time; A ₀ ~ A ₆ is the calculation coefficient of the heat dissipation of the heat collecting tube; T _a is the average value of the ambient temperature at the preset start and end time.

The A ₀ to A ₆ can be selected from A ₀ =0.357, A ₁ =0.0524, A ₂ =-2.96×10 ^-4 , A ₃ =1.126×10 ^-6 , A ₄ =1.068×10 ^-8 , A ₅ = -0.0224, A ₆ =0.002012, A ₀ =0.801, A ₁ =0.0494, A ₂ =-2.92×10 ^-4 , A ₃ =1.13×10 ^-6 , A ₄ =1.524×10 ^-8 , A ₅ =-0.34, A ₆ =0.0025

The IAM in the temperature prediction model can be calculated by the calculation module as follows:

K _θb (θ) in the temperature prediction model can be calculated by the calculation module as follows:

In the formula, f is the focal length of the collector; L is the length of the collector.

The Q _{loss and pipe} in the temperature prediction model can be calculated by the calculation module as follows:

In the formula, D _o is the outer diameter of the pipe connected to the heat collector wrapped with insulation material; D _i is the inner diameter of the pipe connected to the heat collector; λ is the thermal conductivity of the heat insulation material; Thermal coefficient; T _a1 is the average temperature of the outer surface of the pipe connected to the collector at the preset start and end time; T _a2 is the average ambient temperature at the preset start and end time.

Prediction modules can be used to:

Substitute the actual value of the optical efficiency of the collector into the temperature prediction model;

Calculate the predicted value T _{out,cal of} the outlet temperature of the mirror field of the trough solar thermal power station through the temperature prediction model, as follows:

In the formula, G _e,cal is the predicted value of direct solar radiation intensity in the time period to be predicted; T _in,real is the inlet temperature of the trough circuit at the current moment.

The prediction method and system provided by the present invention can accurately predict the outlet temperature of the mirror field within a certain period of time in the future by calculating the actual value of the optical efficiency of the collector and the pre-built temperature prediction model, which is helpful for timely adjustment and control of the tracking angle of the trough concentrator , It is of great significance to prevent the heat transfer oil in the heat collecting tube from overheating and cracking.

Those skilled in the art should understand that the embodiments of the present application may be provided as methods, systems, or computer program products. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowcharts and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a An apparatus for realizing the functions specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart or blocks of the flowchart and/or the block or blocks of the block diagrams.

The above are only embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included in the pending application of the present invention. within the scope of the claims.

Claims (13)

1. A kind of 1. Forecasting Methodology of slot type photo-thermal power station mirror field outlet temperature, it is characterised in that including：

   Obtain the actual operation parameters in preset time period slot type photo-thermal power station；

   The actual operation parameters in the preset time period slot type photo-thermal power station are substituted into the temperature prediction model pre-established, with true Determine heat collector optical efficiency actual value；

   It is pre- according to the beam radia intensity of temperature prediction model, heat collector optical efficiency actual value and period to be predicted Measured value, determine slot type photo-thermal power station mirror field exit temperature prediction value.
2. 2. the Forecasting Methodology of slot type photo-thermal power station mirror field as claimed in claim 1 outlet temperature, it is characterised in that will be described pre- If the actual operation parameters in period slot type photo-thermal power station substitute into temperature prediction model, to determine heat collector optical efficiency reality Value, including：

   The actual operation parameters in the preset time period slot type photo-thermal power station are substituted into the temperature prediction model such as following formula：

   <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> <mrow> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mi>o</mi> <mi>u</mi> <mi>t</mi> </mrow> </msub> <mo>-</mo> <msub> <mi>T</mi> <mrow> <mi>i</mi> <mi>n</mi> </mrow> </msub> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>&amp;eta;K</mi> <mrow> <mi>&amp;theta;</mi> <mi>b</mi> </mrow> </msub> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> <msub> <mi>G</mi> <mi>e</mi> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> <mo>-</mo> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> <mo>-</mo> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> <mo>,</mo> <mi>p</mi> <mi>i</mi> <mi>p</mi> <mi>e</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> <mo>-</mo> <msub> <mi>C</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mfrac> <mrow> <msub> <mi>dT</mi> <mi>m</mi> </msub> </mrow> <mrow> <mi>d</mi> <mi>t</mi> </mrow> </mfrac> </mrow>

   In formula, actual operation parameters include：The slot type circuit entrance temperature T of default initial time_in, the preset termination moment slot type Circuit outlet actual temperature T_out, heat-transfer fluid mean temperature T_mAnd default starting, the relevant parameter of end time are averaged Value；The default starting, the relevant parameter average value of end time include heat-transfer fluid mass flow average valueHeat-transfer fluid Specific heat capacity average value c_f, slot type loop thermal-arrest area average A_a, heat collector heat dissipation capacity average value Q_loss, connection heat collector pipe Road heat dissipation capacity average value Q_loss,pipeWith the hot melt average value C in slot type loop_loop；

   η is heat collector optical efficiency actual value；K_θb(θ) is the incident angle function of beam radia；G_eFor beam radia Intensity；T_m=(T_out+T_in)/2；

   Heat collector optical efficiency actual value η is calculated according to the temperature prediction model.
3. 3. the Forecasting Methodology of slot type photo-thermal power station mirror field as claimed in claim 2 outlet temperature, it is characterised in that the Q_loss It is calculated as follows：

   <mrow> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> </mrow> </msub> <mo>=</mo> <msub> <mi>A</mi> <mn>0</mn> </msub> <mo>+</mo> <msub> <mi>A</mi> <mn>1</mn> </msub> <mrow> <mo>(</mo> <msub> <mi>T</mi> <mi>m</mi> </msub> <mo>-</mo> <msub> <mi>T</mi> <mi>a</mi> </msub> <mo>)</mo> </mrow> <mo>+</mo> <msub> <mi>A</mi> <mn>2</mn> </msub> <msup> <msub> <mi>T</mi> <mi>m</mi> </msub> <mn>2</mn> </msup> <mo>+</mo> <msub> <mi>A</mi> <mn>3</mn> </msub> <msup> <msub> <mi>T</mi> <mi>m</mi> </msub> <mn>3</mn> </msup> <mo>+</mo> <msub> <mi>A</mi> <mn>4</mn> </msub> <msup> <msub> <mi>T</mi> <mi>m</mi> </msub> <mn>2</mn> </msup> <msub> <mi>G</mi> <mi>e</mi> </msub> <mi>c</mi> <mi>o</mi> <mi>s</mi> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> <mi>I</mi> <mi>A</mi> <mi>M</mi> <mo>+</mo> <msqrt> <msub> <mi>V</mi> <mi>w</mi> </msub> </msqrt> <mrow> <mo>(</mo> <msub> <mi>A</mi> <mn>5</mn> </msub> <mo>+</mo> <msub> <mi>A</mi> <mn>6</mn> </msub> <mo>(</mo> <mrow> <msub> <mi>T</mi> <mi>m</mi> </msub> <mo>-</mo> <msub> <mi>T</mi> <mi>a</mi> </msub> </mrow> <mo>)</mo> <mo>)</mo> </mrow> </mrow>

   In formula, θ is default starting, the beam radia incidence angle average value of end time；IAM is incident angle modifier；V_w For default starting, the ambient wind velocity average value of end time；A₀~A₆For the design factor of thermal-collecting tube heat dissipation capacity；T_aTo preset Begin, the environment temperature average value of end time.
4. 4. the Forecasting Methodology of slot type photo-thermal power station mirror field as claimed in claim 3 outlet temperature, it is characterised in that the A₀= 0.357、A₁=0.0524, A₂=-2.96 × 10^-4、A₃=1.126 × 10^-6、A₄=1.068 × 10^-8、A₅=-0.0224, A₆= 0.002012, or A₀=0.801, A₁=0.0494, A₂=-2.92 × 10^-4、A₃=1.13 × 10^-6、A₄=1.524 × 10^-8、 A₅=-0.34, A₆=0.0025.
5. 5. the Forecasting Methodology of prediction slot type photo-thermal power station mirror field outlet temperature as claimed in claim 3, it is characterised in that described IAM is calculated as follows：

   <mrow> <mi>I</mi> <mi>&amp;Lambda;</mi> <mi>M</mi> <mo>=</mo> <mn>1</mn> <mo>+</mo> <mn>0.000884</mn> <mfrac> <mi>&amp;theta;</mi> <mrow> <mi>cos</mi> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> </mrow> </mfrac> <mo>-</mo> <mn>0.00005369</mn> <mfrac> <msup> <mi>&amp;theta;</mi> <mn>2</mn> </msup> <mrow> <mi>cos</mi> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> </mrow> </mfrac> <mo>.</mo> </mrow>
6. 6. the Forecasting Methodology of prediction slot type photo-thermal power station mirror field outlet temperature as claimed in claim 4, it is characterised in that described K_θb(θ) is calculated as follows：

   <mrow> <msub> <mi>K</mi> <mrow> <mi>&amp;theta;</mi> <mi>b</mi> </mrow> </msub> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> <mo>=</mo> <mi>c</mi> <mi>o</mi> <mi>s</mi> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> <mi>I</mi> <mi>A</mi> <mi>M</mi> <mrow> <mo>(</mo> <mn>1</mn> <mo>-</mo> <mfrac> <mi>f</mi> <mi>L</mi> </mfrac> <mi>t</mi> <mi>a</mi> <mi>n</mi> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> <mo>)</mo> </mrow> </mrow>

   In formula, f is heat collector focal length；L is the length of heat collector.
7. 7. the Forecasting Methodology of slot type photo-thermal power station mirror field as claimed in claim 2 outlet temperature, it is characterised in that described Q_loss,pipeIt is calculated as follows：

   <mrow> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> <mo>,</mo> <mi>p</mi> <mi>i</mi> <mi>p</mi> <mi>e</mi> </mrow> </msub> <mo>=</mo> <mfrac> <mrow> <mn>2</mn> <mi>&amp;pi;</mi> <mrow> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mi>a</mi> <mn>1</mn> </mrow> </msub> <mo>-</mo> <msub> <mi>T</mi> <mrow> <mi>a</mi> <mn>2</mn> </mrow> </msub> <mo>)</mo> </mrow> </mrow> <mrow> <mfrac> <mn>1</mn> <mi>&amp;lambda;</mi> </mfrac> <mi>l</mi> <mi>n</mi> <mfrac> <msub> <mi>D</mi> <mi>o</mi> </msub> <msub> <mi>D</mi> <mi>i</mi> </msub> </mfrac> <mo>+</mo> <mfrac> <mn>2</mn> <mrow> <msub> <mi>&amp;alpha;D</mi> <mi>o</mi> </msub> </mrow> </mfrac> </mrow> </mfrac> </mrow>

   In formula, D_oTo connect the external diameter after the duct wraps insulation material of heat collector；D_iTo connect the internal diameter of the pipeline of heat collector；λ is The thermal conductivity of insulation material；α is the pipe surface heat transfer coefficient of connection heat collector；T_a1For default starting, the connection of end time The pipeline external surface temperature averages of heat collector；T_a2For default starting, the environment temperature average value of end time.
8. 8. the Forecasting Methodology of slot type photo-thermal power station mirror field as claimed in claim 2 outlet temperature, it is characterised in that according to temperature The beam radia prediction of strength value of forecast model, heat collector optical efficiency actual value and period to be predicted, determines groove Formula photo-thermal power station mirror field exit temperature prediction value includes：

   Heat collector optical efficiency actual value is substituted into temperature prediction model；

   Slot type photo-thermal power station mirror field exit temperature prediction value T is calculated by temperature prediction model_out,cal, such as following formula：

   <mrow> <msub> <mi>T</mi> <mrow> <mi>o</mi> <mi>u</mi> <mi>t</mi> <mo>,</mo> <mi>c</mi> <mi>a</mi> <mi>l</mi> </mrow> </msub> <mo>=</mo> <mfrac> <mrow> <msub> <mi>&amp;eta;K</mi> <mrow> <mi>&amp;theta;</mi> <mi>b</mi> </mrow> </msub> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> <msub> <mi>G</mi> <mrow> <mi>e</mi> <mo>,</mo> <mi>c</mi> <mi>a</mi> <mi>l</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> </mrow> <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> </mrow> </mfrac> <mo>-</mo> <mfrac> <mrow> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> </mrow> <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> </mrow> </mfrac> <mo>-</mo> <mfrac> <mrow> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> <mo>,</mo> <mi>p</mi> <mi>i</mi> <mi>p</mi> <mi>e</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> </mrow> <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> </mrow> </mfrac> <mo>-</mo> <mfrac> <msub> <mi>C</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> </mrow> </mfrac> <mfrac> <mrow> <msub> <mi>dT</mi> <mi>m</mi> </msub> </mrow> <mrow> <mi>d</mi> <mi>t</mi> </mrow> </mfrac> <mo>+</mo> <msub> <mi>T</mi> <mrow> <mi>i</mi> <mi>n</mi> <mo>,</mo> <mi>r</mi> <mi>e</mi> <mi>a</mi> <mi>l</mi> </mrow> </msub> </mrow>

   In formula, G_e,calFor the beam radia prediction of strength value of period to be predicted；T_in,realReturned for the slot type at current time Road inlet temperature.
9. A kind of 9. forecasting system of slot type photo-thermal power station mirror field outlet temperature, it is characterised in that including：

   Acquisition module, obtain the actual operation parameters in preset time period slot type photo-thermal power station；

   Computing module, the actual operation parameters in the preset time period slot type photo-thermal power station are substituted into the temperature prediction pre-established Model, to determine heat collector optical efficiency actual value；

   Prediction module, according to the direct sunlight of temperature prediction model, heat collector optical efficiency actual value and period to be predicted Radiation intensity predicted value, determine slot type photo-thermal power station mirror field exit temperature prediction value；

   Modeling module, for pre-establishing and storage temperature forecast model.
10. 10. the forecasting system of slot type photo-thermal power station mirror field as claimed in claim 9 outlet temperature, it is characterised in that described to adopt Collect the actual operation parameters that module obtains preset time period slot type photo-thermal power station, including：

    The slot type circuit entrance temperature T of default initial time_in, the preset termination moment slot type circuit outlet actual temperature T_out, pass The mean temperature T of hot fluid_mAnd default starting, the relevant parameter average value of end time；The default starting, end time Relevant parameter average value include heat-transfer fluid mass flow average valueHeat-transfer fluid specific heat capacity average value c_f, slot type loop collection Hot area average A_a, heat collector heat dissipation capacity average value Q_loss, connection heat collector pipe heat dissipation average value Q_loss,pipeAnd groove The hot melt average value C in formula loop_loop。
11. 11. the forecasting system of slot type photo-thermal power station mirror field as claimed in claim 10 outlet temperature, it is characterised in that described to build Mould module, for building the temperature prediction model such as following formula：

    <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> <mrow> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mi>o</mi> <mi>u</mi> <mi>t</mi> </mrow> </msub> <mo>-</mo> <msub> <mi>T</mi> <mrow> <mi>i</mi> <mi>n</mi> </mrow> </msub> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>&amp;eta;K</mi> <mrow> <mi>&amp;theta;</mi> <mi>b</mi> </mrow> </msub> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> <msub> <mi>G</mi> <mi>e</mi> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> <mo>-</mo> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> <mo>-</mo> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> <mo>,</mo> <mi>p</mi> <mi>i</mi> <mi>p</mi> <mi>e</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> <mo>-</mo> <msub> <mi>C</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mfrac> <mrow> <msub> <mi>dT</mi> <mi>m</mi> </msub> </mrow> <mrow> <mi>d</mi> <mi>t</mi> </mrow> </mfrac> </mrow>

    In formula, η is heat collector optical efficiency actual value；K_θb(θ) is the incident angle function of beam radia；G_eFor direct sunlight Radiation intensity；T_m=(T_out+T_in)/2。
12. 12. the forecasting system of slot type photo-thermal power station mirror field as claimed in claim 11 outlet temperature, it is characterised in that the meter Module is calculated, for the actual operation parameters in the preset time period slot type photo-thermal power station to be substituted into temperature prediction model and calculate collection Hot device optical efficiency actual value.
13. 13. the forecasting system of slot type photo-thermal power station mirror field as claimed in claim 12 outlet temperature, it is characterised in that described pre- Module is surveyed to be used for,

    Heat collector optical efficiency actual value is substituted into temperature prediction model；

    Slot type photo-thermal power station mirror field exit temperature prediction value T is calculated by temperature prediction model_out,cal, such as following formula：

    <mrow> <msub> <mi>T</mi> <mrow> <mi>o</mi> <mi>u</mi> <mi>t</mi> <mo>,</mo> <mi>c</mi> <mi>a</mi> <mi>l</mi> </mrow> </msub> <mo>=</mo> <mfrac> <mrow> <msub> <mi>&amp;eta;K</mi> <mrow> <mi>&amp;theta;</mi> <mi>b</mi> </mrow> </msub> <mrow> <mo>(</mo> <mi>&amp;theta;</mi> <mo>)</mo> </mrow> <msub> <mi>G</mi> <mrow> <mi>e</mi> <mo>,</mo> <mi>c</mi> <mi>a</mi> <mi>l</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> </mrow> <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> </mrow> </mfrac> <mo>-</mo> <mfrac> <mrow> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> </mrow> <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> </mrow> </mfrac> <mo>-</mo> <mfrac> <mrow> <msub> <mi>Q</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>s</mi> <mi>s</mi> <mo>,</mo> <mi>p</mi> <mi>i</mi> <mi>p</mi> <mi>e</mi> </mrow> </msub> <msub> <mi>A</mi> <mi>a</mi> </msub> </mrow> <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> </mrow> </mfrac> <mo>-</mo> <mfrac> <msub> <mi>C</mi> <mrow> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mrow> <mover> <mi>m</mi> <mo>&amp;CenterDot;</mo> </mover> <msub> <mi>c</mi> <mi>f</mi> </msub> </mrow> </mfrac> <mfrac> <mrow> <msub> <mi>dT</mi> <mi>m</mi> </msub> </mrow> <mrow> <mi>d</mi> <mi>t</mi> </mrow> </mfrac> <mo>+</mo> <msub> <mi>T</mi> <mrow> <mi>i</mi> <mi>n</mi> <mo>,</mo> <mi>r</mi> <mi>e</mi> <mi>a</mi> <mi>l</mi> </mrow> </msub> </mrow>

    In formula, G_e,calFor the beam radia prediction of strength value of period to be predicted；T_in,realReturned for the slot type at current time Road inlet temperature.