Photovoltaic system heat collector testing method and device

Abstract

The invention provides a photovoltaic system heat collector testing method and device, and relates to the technical field of photovoltaic test.The method comprises the steps that the photovoltaic system heat collector testing device is started; the heat collection amount of a heat collector is determined according to the inlet temperature and the outlet temperature in a preset time period, and the heat storage amount is determined according to the water body temperature; screening time points according to the difference between the heat collection capacity and the heat storage capacity so as to determine a target time point; and the heat collection efficiency at the target time point is obtained, an efficiency curve is obtained through fitting according to the heat collection efficiency, and the total power of the heat collector is obtained according to the efficiency curve. By collecting the data and screening the time points, the efficiency curve and the power of the heat collector are obtained, the test result is prevented from being influenced by deviation data, and the test accuracy of the heat collector is improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic testing technology, and in particular to a photovoltaic system collector testing method and device. Background Art

[0002] As one of the most mature solar thermal utilization equipment, the collector is widely used in solar thermal power stations, industrial hot water / steam supply and other fields. The heat collection efficiency of the collector determines the efficiency of its solar energy utilization, so a special system needs to be designed to evaluate its heat collection efficiency.

[0003] At present, general solar collector system test platforms mainly calculate the energy input by the sun into the solar collector circuit based on the measurement of direct radiation intensity and the combination of the circuit collector area and the incident angle. Due to the large amount of invalid data, the accuracy of the collector test results is poor. Summary of the invention

[0004] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0005] To this end, the first objective of the present application is to propose a photovoltaic system collector testing method.

[0006] The second object of the present application is to provide a device.

[0007] The third object of this application is to provide a system.

[0008] The fourth objective of the present application is to provide an electronic device.

[0009] A fifth objective of the present application is to provide a computer-readable storage medium.

[0010] A sixth object of the present application is to provide a computer program product.

[0011] To achieve the above-mentioned purpose, the first embodiment of the present application proposes a photovoltaic system collector testing method, comprising:

[0012] Starting the photovoltaic system collector testing device within a preset period of sunny weather;

[0013] Continuously collecting the inlet temperature, outlet temperature and water temperature;

[0014] Determine the heat collection amount of the collector according to the inlet temperature and the outlet temperature in a preset time period, and determine the heat storage amount according to the water body temperature;

[0015] Screening the time point according to the difference between the heat collection amount and the heat storage amount to determine the target time point;

[0016] The heat collection efficiency at the target time point is obtained, and an efficiency curve is obtained according to the heat collection efficiency fitting, and the total power of the collector is obtained according to the efficiency curve.

[0017] Optionally, determining the heat collection amount of the collector according to the inlet temperature and the outlet temperature in a preset time period includes:

[0018]

[0019] Among them, Q c is the heat collected by the collector, t i is the time point at which the preset time period starts, is the mass flow rate of the working water flowing through the collector, C pl is the specific heat capacity of the working fluid water, T in is the inlet temperature, T out is the outlet temperature, and Δt is the time interval.

[0020] Optionally, determining the heat storage amount according to the water body temperature includes:

[0021]

[0022] Among them, Q t is the heat storage capacity, M t is the mass of the liquid stored in the hot water storage tank, C pt is the specific heat capacity of the liquid in the hot water storage tank, For i the temperature of the water body at a point in time, For i The water temperature at the +5min time point.

[0023] Optionally, the step of screening the time point according to the difference between the heat collection amount and the heat storage amount to determine the target time point includes:

[0024] In response to the difference between the collected heat amount and the stored heat amount being less than or equal to a preset deviation threshold, determining a time point within a corresponding time period as the target time point;

[0025] In response to the difference between the collected heat amount and the stored heat amount being greater than a preset deviation threshold, it is determined that the time point within the corresponding time period is not the target time point.

[0026] Optionally, obtaining the heat collection efficiency at the target time point includes:

[0027]

[0028] Wherein, η is the heat collection efficiency, A cis the effective area of ​​the collector, I t is the total solar radiation at time t;

[0029] The normalized temperature difference is obtained according to the inlet temperature and the outlet temperature, and the formula is as follows:

[0030]

[0031] Among them, is the normalized temperature difference, is the ambient temperature, and G is the solar irradiance.

[0032] Optionally, acquiring an efficiency curve according to the heat collection efficiency fitting, and acquiring the total power of the collector according to the efficiency curve comprises:

[0033] Establishing a rectangular coordinate system with the heat collection efficiency and the normalized temperature difference;

[0034] Plotting the heat collection efficiency and the normalized temperature difference corresponding to the target time point in the rectangular coordinate system;

[0035] Fitting discrete points in the rectangular coordinate system to generate the efficiency curve;

[0036] The total power at each moment is obtained, and the calculation formula is as follows:

[0037] P=G·A c ·η.

[0038] To achieve the above-mentioned purpose, the second embodiment of the present application proposes a photovoltaic system collector test device, comprising: a flow meter, a first temperature sensor, a collector, a second temperature sensor, a hot water storage tank, a heat exchanger, a constant temperature water tank, a water pump, and a flow regulating valve arranged in sequence in the same pipeline circulation loop;

[0039] A solar total radiation meter, a solar scattered radiation meter, and an ambient temperature sensor are arranged around the collector;

[0040] The first temperature sensor is used to obtain the inlet temperature of the collector, the second temperature sensor is used to obtain the outlet temperature of the collector, the flow meter is used to obtain the mass flow of the working medium water flowing through the collector, and the ambient temperature sensor is used to obtain the ambient temperature;

[0041] The heat storage tank and the heat exchanger are used to exchange and store the heat of the working medium water in the pipeline circulation loop. The liquid in the heat storage tank is isolated from the working medium water in the pipeline circulation loop by a pipeline. The heat storage tank is provided with a third temperature sensor for obtaining the water temperature of the heat storage tank;

[0042] The constant temperature water tank is used to adjust the temperature of the working medium water in the pipeline circulation loop to a preset range;

[0043] The water pump is used to pump the water in the constant temperature water tank into the collector.

[0044] To achieve the above-mentioned purpose, the third embodiment of the present application proposes a photovoltaic system collector testing system, comprising:

[0045] A starting module, used to start the photovoltaic system collector testing device within a preset period of sunny weather;

[0046] A data acquisition module, used for continuously collecting the inlet temperature, outlet temperature and water temperature;

[0047] A heat calculation module, used to determine the heat collection amount of the collector according to the inlet temperature and the outlet temperature in a preset time period, and to determine the heat storage amount according to the water body temperature;

[0048] A screening module, used for screening time points according to the difference between the collected heat amount and the stored heat amount to determine a target time point;

[0049] The power calculation module is used to obtain the heat collection efficiency at the target time point, obtain an efficiency curve according to the heat collection efficiency, and obtain the total power of the collector according to the efficiency curve.

[0050] To achieve the above-mentioned purpose, a fourth aspect of the present application provides an electronic device, comprising: a processor, and a memory communicatively connected to the processor;

[0051] The memory stores computer-executable instructions;

[0052] The processor executes the computer-executable instructions stored in the memory to implement the method as described in any one of the first aspects.

[0053] To achieve the above-mentioned purpose, the fifth aspect embodiment of the present application proposes a computer-readable storage medium, in which computer-readable storage medium is stored computer execution instructions, and when the computer execution instructions are executed by a processor, they are used to implement the method as described in any one of the first aspects.

[0054] To achieve the above-mentioned purpose, the sixth aspect of the present application proposes a computer program product, which implements any method in the first aspect when executed by a processor.

[0055] The photovoltaic system collector testing method, device, electronic device and storage medium provided in the present application realize the acquisition of collector efficiency curve and power by collecting data and screening time points, avoid the influence of biased data on test results, and improve the accuracy of collector testing.

[0056] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0058] Figure 1 A schematic diagram of the structure of a photovoltaic system collector testing device provided in an embodiment of the present application;

[0059] Figure 2 A schematic diagram of a photovoltaic system collector testing method provided in an embodiment of the present application;

[0060] Figure 3 A schematic diagram of an instantaneous efficiency curve of a collector provided in an embodiment of the present application;

[0061] Figure 4 A schematic diagram of the structure of a photovoltaic system collector testing system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0062] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0063] The present application embodiment provides a photovoltaic system collector testing device, Figure 1 A schematic diagram of a photovoltaic system collector testing device provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the device comprises: a flow meter 1, a first temperature sensor 2, a heat collector 3, a second temperature sensor 4, a hot water storage tank 5, a heat exchanger 6, a constant temperature water tank 7, a water pump 8, and a flow regulating valve 9 which are sequentially arranged in the same pipeline circulation loop;

[0064] A solar total radiation meter 10, a solar scattered radiation meter 11, and an ambient temperature sensor 12 are arranged around the collector;

[0065] The first temperature sensor 2 is used to obtain the inlet temperature of the collector 3, the second temperature sensor 4 is used to obtain the outlet temperature of the collector 3, the flow meter 1 is used to obtain the mass flow of the working medium water flowing through the collector 3, and the ambient temperature sensor 12 is used to obtain the ambient temperature;

[0066] The hot water storage tank 5 and the heat exchanger 6 are used to exchange and store the heat of the working medium water in the pipeline circulation loop. The liquid in the hot water storage tank 5 is isolated from the working medium water in the pipeline circulation loop by a pipeline. The hot water storage tank 5 is provided with a third temperature sensor 13 for obtaining the water temperature of the hot water storage tank;

[0067] The constant temperature water tank 7 is used to adjust the temperature of the working medium water in the pipeline circulation loop to a preset range;

[0068] The water pump 8 is used to pump the water in the constant temperature water tank 7 into the heat collector 3 .

[0069] In this embodiment, the calculation variance of the collector efficiency can be expressed as:

[0070]

[0071] Where:

[0072] F R - Heat transfer factor;

[0073] t fi -Collector working medium inlet temperature, °C;

[0074] t a -Ambient temperature, °C;

[0075] τ-transmittance of flat-plate collector cover;

[0076] α- flat-plate collector film absorption rate;

[0077] U I - Heat dissipation coefficient of flat plate collector, W / (m 2 .℃);

[0078] G-solar radiation, W / m 2 .

[0079] According to the above efficiency equation, with the collector efficiency η as the ordinate, (t fi -t a ) / G as the horizontal axis, a straight line can be obtained. In this curve: the intercept (hereinafter referred to as light efficiency, which refers to the instantaneous efficiency of the flat-plate collector when the fluid inlet temperature is equal to the outside temperature, as the highest instantaneous efficiency theoretically achieved; the slope is the total loss coefficient of the flat-plate collector, that is, the loss per unit time, unit lighting area, unit temperature difference between the fluid inlet temperature and the outside temperature, which is the degree of heat loss in actual work. The instantaneous efficiency experiment is to artificially determine the collector working conditions and calculate the heat loss under different working conditions (t fi -t a) / G and its corresponding η value, and organize the experimental data, plot the experimental points on the coordinate graph, and then use the least squares method to fit the experimental data points into a straight line, and finally get the expression of instantaneous efficiency. The reasonable basis for judging the thermal performance of the collector is the efficiency equation based on the lighting area fitting. The judging indicators include the static and quasi-static instantaneous efficiency intercept η and the size of the total heat dissipation coefficient U.

[0080] Steady-state and quasi-steady-state instantaneous efficiency intercepts are based on the normalized temperature difference The instantaneous efficiency value under the condition of no heat loss is the maximum efficiency that the collector can achieve. It reflects the efficiency of the collector under the condition of no heat loss. According to the technical requirements for the production of collectors specified in the standard, the instantaneous efficiency intercept of flat-plate solar collectors should be no less than 0.72.

[0081] The total heat loss coefficient U reflects the size of the collector loss. The loss generated by the collector increases with the increase of the total loss, and vice versa. Therefore, the smaller the total loss coefficient of the collector, the better the thermal performance of the collector. According to the production technical requirements of flat-plate collectors specified in the standard, the maximum total loss coefficient of flat-plate collectors is 6W·m 2 ℃ -1 .

[0082] In order to obtain the performance of the collector, the present embodiment builds a corresponding experimental platform, namely, the photovoltaic system collector test device. The experiment uses water as the circulating working medium. First, water flows in from the inlet end of the collector. The collector absorbs solar energy to increase the temperature of the collector plate. The collector plate transfers the heat to the circulating working medium through heat conduction and convection. After absorbing heat and heating up, it flows out from the outlet of the collector as high-temperature water and enters the hot water storage tank. The high-temperature water flowing out of the hot water storage tank exchanges heat with low-temperature water through a heat exchanger. It becomes low-temperature water and enters the constant temperature water tank for standby. After the constant temperature effect of the electric heater, it becomes constant temperature water and flows through the circulating water pump, and then flows into the inlet end of the collector again to complete the circulation process. The temperature sensor is located at the inlet and outlet of the collector working medium, which is used to measure the inlet temperature and outlet temperature of the working medium. The flow meter is installed at the inlet of the collector, which is used to measure the total mass flow of the working water in the system. The total solar irradiance can be measured by the global radiation meter, and the solar scattered radiation can be measured by the scattered radiation meter. The lighting area of ​​the flat-plate collector is known. The inlet and outlet temperatures of the collector can be measured by the temperature sensor, and the inlet and outlet temperature difference can be calculated, thereby calculating the useful energy of the collector.

[0083] The present application embodiment provides a photovoltaic system collector testing method, Figure 2 The following is a flow chart of a photovoltaic system collector testing method provided in an embodiment of the present application. Figure 2 As shown, the method comprises the following steps:

[0084] Step 201, starting the photovoltaic system collector testing device within a preset period of sunny weather;

[0085] Step 202, continuously collecting the inlet temperature, outlet temperature and water temperature;

[0086] Step 203, determining the heat collection amount of the collector according to the inlet temperature and the outlet temperature in a preset time period, and determining the heat storage amount according to the water body temperature;

[0087] Step 204, screening the time point according to the difference between the heat collection amount and the heat storage amount to determine the target time point;

[0088] Step 205, obtaining the heat collection efficiency at the target time point, and obtaining an efficiency curve according to the heat collection efficiency fitting, and obtaining the total power of the collector according to the efficiency curve.

[0089] In this embodiment, the preset time period is a time period of stronger light in a day. Optionally, the preset time period shown is 2 hours before and after 14:20 local true solar time.

[0090] Optionally, the step 203 of determining the heat collection amount of the collector according to the inlet temperature and the outlet temperature in a preset time period includes:

[0091]

[0092] Among them, Q c is the heat collected by the collector, t i is the time point at which the preset time period starts, is the mass flow rate of the working water flowing through the collector, C pl is the specific heat capacity of the working fluid water, T in is the inlet temperature, T out is the outlet temperature, and Δt is the time interval.

[0093] Optionally, the step 203 determines the heat storage amount according to the water body temperature, including:

[0094] Q t =M t C pt (T ti+5min -T ti );

[0095] Among them, Q t is the heat storage capacity, M t is the mass of the liquid stored in the hot water storage tank, C pt is the specific heat capacity of the liquid in the hot water storage tank, T ti For i The water temperature at a given time, Tti+5min For i The water temperature at the +5min time point.

[0096] Optionally, the step 204 selects a time point according to the difference between the heat collection amount and the heat storage amount to determine a target time point, including:

[0097] In response to the difference between the collected heat amount and the stored heat amount being less than or equal to a preset deviation threshold, determining a time point within a corresponding time period as the target time point;

[0098] In response to the difference between the collected heat amount and the stored heat amount being greater than a preset deviation threshold, it is determined that the time point within the corresponding time period is not the target time point.

[0099] Optionally, the step 205 of obtaining the heat collection efficiency at the target time point includes:

[0100]

[0101] Wherein, η is the heat collection efficiency, A c is the effective area of ​​the collector, I t is the total solar radiation at time t;

[0102] The normalized temperature difference is obtained according to the inlet temperature and the outlet temperature, and the formula is as follows:

[0103]

[0104] Among them, is the normalized temperature difference, is the ambient temperature, and G is the solar irradiance.

[0105] Optionally, the step 205 obtains an efficiency curve according to the heat collection efficiency fitting, and obtaining the total power of the collector according to the efficiency curve includes:

[0106] Establishing a rectangular coordinate system with the heat collection efficiency and the normalized temperature difference;

[0107] Plotting the heat collection efficiency and the normalized temperature difference corresponding to the target time point in the rectangular coordinate system;

[0108] Fitting discrete points in the rectangular coordinate system to generate the efficiency curve;

[0109] The total power at each moment is obtained, and the calculation formula is as follows:

[0110] P=G·A c ·η.

[0111] In a possible embodiment, a sunny day in the area where the test device is located is selected for experimental testing, and the test time is 2 hours before and after 14:20 local true solar time, and the scattered radiation during the test is ≤20%. During the test, by comparing the deviation between the heat collection of the collector and the heat storage of the water tank within a 5-minute time interval, if the deviation is within the range of 10%, a quasi-steady-state measurement point screening is performed, and after calculating the corresponding collector heat collection efficiency, it is marked in the rectangular coordinate diagram, and finally fitted into an efficiency curve using the least squares method; if the deviation is outside the range of 10%, the experiment is continued until the deviation falls within the range of 10%. Figure 3 A schematic diagram of an instantaneous efficiency curve of a collector provided in an embodiment of the present application is shown in FIG. Figure 3 As shown in the figure, after calculating the corresponding collector efficiency, it is marked in the rectangular coordinate diagram, and finally fitted into the efficiency curve using the least squares method. The formula of the curve in the figure is η=0.801-2.8032×T m * , where T m * is the normalized temperature difference based on the average inlet and outlet temperatures.

[0112] From the above flat plate collector efficiency curve, it can be concluded that the collector efficiency range is 50%-80%, and the highest efficiency can reach 80%. Through the meteorological resource dedicated software, it can be found that the maximum irradiation value of the project site in a year can reach 1366W / m 2 The size of a large flat plate collector is 5030mm×2270mm, and the collection area is 11.42m 2 , this system uses a total of 4 large flat panel collectors. According to the above data, the total collector power can be calculated to be 31199W-9919W, that is, 31.2kW-49.9kW.

[0113] In order to implement the above embodiments, the present application also proposes a photovoltaic system collector testing system. Figure 4 The schematic diagram of the structure of a photovoltaic system collector test system provided in the embodiment of the present application. Figure 4 As shown, the system includes:

[0114] A starting module 410 is used to start the photovoltaic system collector testing device within a preset period of sunny weather;

[0115] A data acquisition module 420 is used to continuously collect the inlet temperature, outlet temperature and water temperature;

[0116] The heat calculation module 430 is used to determine the heat collection amount of the collector according to the inlet temperature and the outlet temperature in a preset time period, and determine the heat storage amount according to the water body temperature;

[0117] A screening module 440 is used to screen the time points according to the difference between the heat collection amount and the heat storage amount to determine the target time point;

[0118] The power calculation module 450 is used to obtain the heat collection efficiency at the target time point, obtain an efficiency curve according to the heat collection efficiency, and obtain the total power of the collector according to the efficiency curve.

[0119] In order to implement the above embodiments, the present application also proposes an electronic device, comprising: a processor, and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method provided by the above embodiments.

[0120] In order to implement the above embodiments, the present application also proposes a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the methods provided by the above embodiments.

[0121] In order to implement the above embodiments, the present application also proposes a computer program product, including a computer program, which implements the methods provided by the above embodiments when executed by a processor.

[0122] The collection, storage, use, processing, transmission, provision and disclosure of user personal information involved in this application are in compliance with relevant laws and regulations and do not violate public order and good morals.

[0123] It should be noted that personal information from users should be collected for legitimate and reasonable purposes and should not be shared or sold outside of these legitimate uses. In addition, such collection / sharing should be carried out after receiving the user's informed consent, including but not limited to notifying the user to read the user agreement / user notice and sign the agreement / authorization including authorization of relevant user information before the user uses the function. In addition, any necessary steps should be taken to protect and safeguard access to such personal information data and ensure that others who have access to personal information data comply with its privacy policy and procedures.

[0124] The present application is expected to provide an implementation scheme for users to selectively block the use or access of personal information data. That is, the present disclosure is expected to provide hardware and / or software to prevent or block access to such personal information data. Once the personal information data is no longer needed, the risk can be minimized by limiting data collection and deleting the data. In addition, when applicable, such personal information is de-identified to protect the privacy of the user.

[0125] In the description of the aforementioned embodiments, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0126] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0127] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0128] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute the instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0129] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0130] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0131] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0132] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A photovoltaic system collector testing device, characterized in that: include: The flow meter, the first temperature sensor, the heat collector, the second temperature sensor, the hot water storage tank, the heat exchanger, the constant temperature water tank, the water pump, and the flow regulating valve are sequentially arranged in the same pipeline circulation loop; A solar total radiation meter, a solar scattered radiation meter, and an ambient temperature sensor are arranged around the collector; The first temperature sensor is used to obtain the inlet temperature of the collector, the second temperature sensor is used to obtain the outlet temperature of the collector, the flow meter is used to obtain the mass flow of the working medium water flowing through the collector, and the ambient temperature sensor is used to obtain the ambient temperature; The heat storage tank and the heat exchanger are used to exchange and store the heat of the working medium water in the pipeline circulation loop. The liquid in the heat storage tank is isolated from the working medium water in the pipeline circulation loop by a pipeline. The heat storage tank is provided with a third temperature sensor for obtaining the water temperature of the heat storage tank; The constant temperature water tank is used to adjust the temperature of the working medium water in the pipeline circulation loop to a preset range; The water pump is used to pump the water in the constant temperature water tank into the collector.

2. A photovoltaic system collector testing method, characterized in that: The photovoltaic system collector testing device as claimed in claim 1 comprises the following steps: Starting the photovoltaic system collector testing device within a preset period of sunny weather; Continuously collecting the inlet temperature, outlet temperature and water temperature; Determine the heat collection amount of the collector according to the inlet temperature and the outlet temperature in a preset time period, and determine the heat storage amount according to the water body temperature; Screening the time point according to the difference between the heat collection amount and the heat storage amount to determine the target time point; The heat collection efficiency at the target time point is obtained, and an efficiency curve is obtained according to the heat collection efficiency fitting, and the total power of the collector is obtained according to the efficiency curve.

3. The method according to claim 2, characterized in that Determining the heat collection amount of the collector according to the inlet temperature and the outlet temperature in the preset time period includes: Among them, Q c is the heat collected by the collector, t i is the time point at which the preset time period starts, is the mass flow rate of the working water flowing through the collector, C pl is the specific heat capacity of the working fluid water, T in is the inlet temperature, T out is the outlet temperature, and Δt is the time interval.

4. The method according to claim 3, characterized in that Determining the heat storage amount according to the water body temperature includes: Among them, Q t is the heat storage capacity, M t is the mass of the liquid stored in the hot water storage tank, C pt is the specific heat capacity of the liquid in the hot water storage tank, For i the temperature of the water body at a point in time, For i The water temperature at the +5min time point.

5. The method according to claim 4, characterized in that The step of screening the time point according to the difference between the heat collection amount and the heat storage amount to determine the target time point comprises: In response to the difference between the collected heat amount and the stored heat amount being less than or equal to a preset deviation threshold, determining a time point within a corresponding time period as the target time point; In response to the difference between the collected heat amount and the stored heat amount being greater than a preset deviation threshold, it is determined that the time point within the corresponding time period is not the target time point.

6. The method according to claim 5, characterized in that The obtaining of the heat collection efficiency at the target time point comprises: Get the collector efficiency Wherein, η is the heat collection efficiency, A c is the effective area of ​​the collector, I t is the total solar radiation at time t; The normalized temperature difference is obtained according to the inlet temperature and the outlet temperature, and the formula is as follows: Among them, is the normalized temperature difference, is the ambient temperature, and G is the solar irradiance.

7. The method according to claim 6, characterized in that The obtaining of an efficiency curve according to the heat collection efficiency fitting, and obtaining the total power of the collector according to the efficiency curve comprises: Establishing a rectangular coordinate system with the heat collection efficiency and the normalized temperature difference; Plotting the heat collection efficiency and the normalized temperature difference corresponding to the target time point in the rectangular coordinate system; Fitting discrete points in the rectangular coordinate system to generate the efficiency curve; The total power at each moment is obtained, and the calculation formula is as follows: P=G·A c ·or.

8. A photovoltaic system collector testing system, characterized in that: include A starting module, used to start the photovoltaic system collector testing device within a preset period of sunny weather; A data acquisition module, used for continuously collecting the inlet temperature, outlet temperature and water temperature; A heat calculation module, used to determine the heat collection amount of the collector according to the inlet temperature and the outlet temperature in a preset time period, and to determine the heat storage amount according to the water body temperature; A screening module, used for screening time points according to the difference between the collected heat amount and the stored heat amount to determine a target time point; The power calculation module is used to obtain the heat collection efficiency at the target time point, obtain an efficiency curve according to the heat collection efficiency, and obtain the total power of the collector according to the efficiency curve.

9. An electronic device, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 2 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 2 to 7 when executed by a processor.

Images