Electric energy metering monitoring system based on photovoltaic protocol conversion

Abstract

The invention discloses an electric energy metering monitoring system based on photovoltaic protocol conversion. The system comprises a front-end data acquisition module, a data storage module, a data preprocessing module and a data analysis module. The front-end data acquisition module is responsible for acquisition of meteorological data and operation parameters, such as solar irradiation intensity and photovoltaic module panel temperature. The data is preprocessed by a data preprocessing module, such as data extraction, marking, filtering and processing. The preprocessed data can be stored in the data storage module and deeply analyzed in the data analysis module so as to obtain the theoretical generation power, the conversion rate and the abnormal information of the photovoltaic module. In addition, the system further comprises a control module which can automatically give an alarm and start troubleshooting when an abnormal condition is detected. In conclusion, the system makes full use of the advanced data processing technology, effectively monitors and controls the operation condition of the photovoltaic power generation system, and improves the photovoltaic power generation efficiency and safety.

Description

Technical Field

[0001] The invention belongs to the field of electric energy metering and monitoring, relates to photovoltaic power generation technology, and specifically is an electric energy metering and monitoring system based on photovoltaic protocol conversion. Background Art

[0002] Solar photovoltaic power generation is a technology that uses solar energy to directly convert light energy into electrical energy. Photovoltaic power generation systems are mainly composed of photovoltaic cells. When sunlight shines on photovoltaic cells, photons interact with atoms in semiconductor materials to produce a photoelectric effect, causing electrons to jump from the valence band to the conduction band and form a current. In this way, photovoltaic cells can be connected in series and in parallel to form a photovoltaic battery group for direct power supply or storage of electrical energy.

[0003] In the existing solar power generation process, solar power generation or grid connection is generally used, but there is no clear calculation for the power generation of non-fixed specifications of photovoltaic modules under different irradiation intensities, and the specific efficiency of photovoltaic conversion is unclear, resulting in many photovoltaic modules being difficult to detect when the power generation is reduced and lacking a means of real-time power generation monitoring;

[0004] To this end, the present invention proposes an electric energy metering and monitoring system based on photovoltaic protocol conversion. Summary of the invention

[0005] The purpose of this application is to provide an electric energy metering and monitoring system based on photovoltaic protocol conversion.

[0006] To achieve the above objectives, the present application provides an electric energy metering and monitoring system based on photovoltaic protocol conversion, comprising:

[0007] Front-end data acquisition module for collecting meteorological data and rated parameters, including solar radiation intensity G ref , the optimal output current I of the photovoltaic module under standard working conditions mref , the optimal output voltage U of photovoltaic modules under standard working conditions mref And the PV panel surface temperature T m , m represents the number of the photovoltaic module, and m=1,2……M;

[0008] Photovoltaic inverters used to convert direct current generated by photovoltaic modules into alternating current for direct use by users or grid-connected use;

[0009] Used to obtain the measured current value I in the circuit where the photovoltaic inverter is connected to the user or connected to the grid m实 The measured voltage value U m实 Current collector and voltage collector;

[0010] and a data analysis module for processing meteorological data and rated parameters;

[0011] The data analysis module uses the calculation formula to obtain the theoretical power generation power P of the photovoltaic module. llm；

[0012] Among them, the theoretical power generation power P ll The calculation formula is:

[0013]

[0014] G e is the effective irradiation intensity on the slope of the photovoltaic module;

[0015] ΔT=T m -T ref , T ref is the standard component temperature;

[0016] ΔG=G e -G ref ; a, b, c are compensation coefficients; e is the base of the natural logarithm, and its value can be 2.71828;

[0017] and calculate conversion rates The conversion rate The calculation formula is:

[0018]

[0019] The data processing module sets the conversion rate threshold

[0020] when When , the data processing module outputs a normal signal to the control module;

[0021] when When the data processing module outputs an abnormal signal to the control module.

[0022] Preferably, the front-end data acquisition module includes a meteorological data acquisition unit and an operating parameter acquisition unit;

[0023] The meteorological data acquisition unit is used to collect meteorological data including solar radiation intensity and photovoltaic module panel surface temperature;

[0024] The operating parameter acquisition unit is used to acquire the rated parameters of the photovoltaic module including the optimal output current of the photovoltaic module under standard working conditions and the optimal output voltage of the photovoltaic module under standard working conditions.

[0025] Preferably, the solar radiation intensity is acquired by a data acquisition unit from a comprehensive climate database according to the geographical location of the photovoltaic module; and the photovoltaic module panel surface temperature is acquired by a temperature sensor installed on the photovoltaic module panel surface.

[0026] Preferably, it also includes a data storage module, which is wirelessly or electrically connected to the front-end data acquisition module;

[0027] The data storage module is used to store the meteorological data and rated parameters collected by the front-end data collection module.

[0028] Preferably, the control module is also used to receive the solar radiation intensity sent by the front-end data acquisition module in real time, and set the lower limit of the solar radiation intensity;

[0029] When the solar radiation intensity is ≥ the lower limit of the solar radiation intensity, the control module generates a first execution signal and sends it to the front-end data acquisition module, and the front-end data acquisition module collects meteorological data and rated parameters.

[0030] Preferably, before processing the meteorological data and the rated parameters, the method further includes:

[0031] The data preprocessing module forms a board surface temperature data set T, where T = [T1, T2, ...T m …、T M ];

[0032] The data preprocessing module obtains the mode in the board surface temperature data set T and marks it as the standard board surface temperature

[0033] Get the error range of the temperature sensor at this temperature, and convert the PV panel temperature T in the panel temperature data set T m and compare it with the error range under the temperature; if it falls within the error range, the data preprocessing module will m Marked as qualified data; when it does not fall within the error range, the data preprocessing module will m Mark as abnormal data.

[0034] Preferably, the control module is connected to the alarm module; when the data processing module outputs an abnormal signal to the control module, the control module is connected to the alarm module to issue an alarm reminder and arrange operators to troubleshoot the photovoltaic components under this number.

[0035] Preferably, the effective irradiance G e , which is determined by the angle between the photovoltaic panel of the photovoltaic module and the direction of solar radiation.

[0036] Preferably, the optimal output current of the photovoltaic module under standard operating conditions and the optimal output voltage of the photovoltaic module under standard operating conditions are both obtained from the nameplate of the photovoltaic module.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The present invention collects the solar radiation intensity G through the front-end data acquisition module ref , the optimal output current I of the photovoltaic module under standard working conditions mref , the optimal output voltage U of photovoltaic modules under standard working conditions mref And the PV panel surface temperature T m , and set a current collector and a voltage collector in the circuit where the photovoltaic inverter is connected to the user or the grid to collect the measured current value I m实 The measured voltage value U m实 ; Use the data analysis module to process meteorological data and rated parameters; The data analysis module uses the calculation formula to obtain the theoretical power generation power P of the photovoltaic module llm And calculate the conversion rate when When , the data processing module outputs a normal signal to the control module; when When the data processing module outputs an abnormal signal to the control module, the control module is connected to the alarm module to give an alarm reminder, and arranges operators to troubleshoot the photovoltaic components under the number. This system makes full use of advanced data processing technology to effectively monitor and control the operation status of the photovoltaic power generation system, and improves the efficiency and safety of photovoltaic power generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 The present invention is a structural block diagram of an electric energy metering and monitoring system based on photovoltaic protocol conversion. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0042] Please refer to Figure 1 , Figure 1 This is a structural block diagram of an electric energy metering and monitoring system based on photovoltaic protocol conversion proposed by the present invention. Figure 1 It can be clearly seen that the electric energy metering monitoring system based on photovoltaic protocol conversion proposed in this application includes:

[0043] A front-end data acquisition module for collecting meteorological data and operating parameter data, the front-end data acquisition module comprising a meteorological data acquisition unit and an operating parameter acquisition unit;

[0044] The meteorological data acquisition unit is used to collect meteorological data including solar radiation intensity and photovoltaic module panel surface temperature;

[0045] The solar radiation intensity is acquired by the data acquisition unit in the comprehensive climate database according to the geographical location of the photovoltaic module; the photovoltaic module panel surface temperature is acquired by the temperature sensor installed on the photovoltaic module panel surface;

[0046] And the operating parameter acquisition unit is used to acquire the rated parameters of the photovoltaic module including the optimal output current of the photovoltaic module under standard working conditions and the optimal output voltage of the photovoltaic module under standard working conditions;

[0047] Among them, the optimal output current of the photovoltaic module under standard working conditions and the optimal output voltage of the photovoltaic module under standard working conditions are obtained from the nameplate of the photovoltaic module;

[0048] as well as

[0049] A data storage module, the data storage module is wirelessly or electrically connected to the front-end data acquisition module; specifically, there is data interaction between the front-end data acquisition module and the data storage module; the data storage module is used to store the meteorological data and rated parameters collected by the front-end data acquisition module, and correspondingly, the front-end data acquisition module uploads the collected meteorological data and rated parameters to the data storage module;

[0050] Obviously, in the application itself, the result of electric energy metering monitoring cannot be achieved by relying solely on the front-end data acquisition module for data acquisition and the data storage module for data storage;

[0051] Therefore, this application also includes a data preprocessing module and a data analysis module;

[0052] The data preprocessing module is used to preprocess the meteorological data and rated parameters stored in the data storage module; specifically, the preprocessing of the data preprocessing module includes:

[0053] Data extraction: The data preprocessing module sends a data extraction signal to the data storage module. After the data storage module receives the extraction signal, the data storage module packages the meteorological data and rated parameters and feeds them back to the data preprocessing module;

[0054] Data marking: The data preprocessing module decompresses the received data packets and marks the data separately, where the solar radiation intensity is marked as G ref , the PV panel surface temperature is marked as T m The optimal output current of the photovoltaic module under standard conditions is marked as I mref The optimal output voltage of the photovoltaic module under standard working conditions is marked as U mref ;

[0055] Wherein, m represents the number of the photovoltaic module, and m=1,2……M;

[0056] In this application, the photovoltaic module surface temperature T m It is self-testing, so when the temperature sensor fails, the PV panel surface temperature T m Will change to form fault temperature data;

[0057] The data preprocessing module is also used to identify and remove faulty temperature data. Specifically, the data preprocessing module marks the surface temperature of the photovoltaic module to form a surface temperature data set T, where T = [T1, T2, ...T m …、T M ];

[0058] The data preprocessing module obtains the mode in the board surface temperature data set T and marks it as the standard board surface temperature

[0059] Get the error range of the temperature sensor at this temperature, and convert the PV panel temperature T in the panel temperature data set T m and compare it with the error range under the temperature; if it falls within the error range, the data preprocessing module will m Marked as qualified data; when it does not fall within the error range, the data preprocessing module will m Mark as abnormal data;

[0060] In one embodiment of the present application, the data preprocessing module is connected to the data analysis module to realize information interaction between the data preprocessing module and the data analysis module;

[0061] The data preprocessing module converts the marked solar radiation intensity G ref , the optimal output current I of the photovoltaic module under standard working conditions mref , the optimal output voltage U of photovoltaic modules under standard working conditions mref And the PV panel surface temperature T marked as qualified data m Send to data analysis module;

[0062] The data analysis module is used to analyze the received solar radiation intensity G ref , the optimal output current I of the photovoltaic module under standard working conditions mref , the optimal output voltage U of photovoltaic modules under standard working conditions mref And the PV panel surface temperature T marked as qualified data m Conduct a comprehensive analysis, specifically:

[0063] The data analysis module uses a calculation formula to obtain the theoretical power generation power P of the photovoltaic module. llm；

[0064] Among them, the theoretical power generation power P ll The calculation formula is:

[0065]

[0066] In this formula, G e is the effective irradiation intensity of the inclined surface of the photovoltaic module, which is determined by the angle between the photovoltaic panel of the photovoltaic module and the direction of solar irradiation;

[0067] ΔT=T m -T ref , T ref is the standard component temperature, generally 25°C;

[0068] ΔG=G e -G ref ; a, b, c are compensation coefficients, which are obtained by fitting according to the experimental data of photovoltaic modules and are regularly revised according to the measured data; e is the base of the natural logarithm, and its value can be 2.71828;

[0069] In the present application, the photovoltaic module is connected to a photovoltaic inverter; wherein the photovoltaic inverter is a device that converts direct current (DC) into alternating current (AC), that is, in the present application, the photovoltaic inverter is used to convert the direct current generated by the photovoltaic module into alternating current for direct use by users or grid-connected use;

[0070] Wherein, in the circuit where the photovoltaic inverter is connected to the user or connected to the grid, a current collector and a voltage collector are added; the user obtains the measured current value and voltage value at the output end of the photovoltaic inverter; and the measured current value and the measured voltage value are marked as: I m实 , U m实 ;

[0071] The current collector and the voltage collector send the measured current value and the measured voltage value to the data preprocessing module;

[0072] After receiving the measured current value and the measured voltage value, the data processing module calculates the conversion rate The conversion rate The calculation formula is:

[0073]

[0074] The data processing module sets the conversion rate threshold The conversion rate threshold is generally determined by the performance of the photovoltaic inverter itself, and is generally 70% to 90%;

[0075] when When , the data processing module outputs a normal signal to the control module;

[0076] when When , the data processing module outputs an abnormal signal to the control module;

[0077] More specifically, the present application further includes a control module, which is used to receive the solar radiation intensity sent by the front-end data acquisition module in real time and set the lower limit of the solar radiation intensity; when the solar radiation intensity is ≥ the lower limit of the solar radiation intensity, the control module generates a first execution signal and sends it to the front-end data acquisition module, and the front-end data acquisition module collects meteorological data and rated parameters;

[0078] The control module is connected to the alarm module; when the data processing module outputs an abnormal signal to the control module, the control module is connected to the alarm module to issue an alarm reminder and arrange operators to troubleshoot the photovoltaic components under the number.

[0079] The above formulas are all calculated by removing dimensions and taking numerical values. The formula is a formula that is closest to the actual situation obtained by collecting a large amount of data and performing software simulation. The preset parameters and preset thresholds in the formula are set by technical personnel in this field according to actual conditions or obtained by simulating a large amount of data.

[0080] Working principle of the present invention:

[0081] The solar radiation intensity G is collected through the front-end data acquisition module ref , the optimal output current I of the photovoltaic module under standard working conditions mref , the optimal output voltage U of photovoltaic modules under standard working conditions mref And the PV panel surface temperature T m , and set a current collector and a voltage collector in the circuit where the photovoltaic inverter is connected to the user or the grid to collect the measured current value I m实 The measured voltage value U m实 ; Use the data analysis module to process meteorological data and rated parameters; The data analysis module uses the calculation formula to obtain the theoretical power generation power P of the photovoltaic module llm And calculate the conversion rate when When , the data processing module outputs a normal signal to the control module; when When , the data processing module outputs an abnormal signal to the control module;

[0082] The control module is connected to the alarm module; when the data processing module outputs an abnormal signal to the control module, the control module is connected to the alarm module to issue an alarm reminder and arrange operators to troubleshoot the photovoltaic components under the number.

[0083] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An electric energy metering and monitoring system based on photovoltaic protocol conversion, characterized in that: include: Front-end data acquisition module for collecting meteorological data and rated parameters, including solar radiation intensity G ref , the optimal output current I of the photovoltaic module under standard working conditions mref , the optimal output voltage U of photovoltaic modules under standard working conditions mref And the PV panel surface temperature T m , m represents the number of the photovoltaic module, and m=1,2……M; Photovoltaic inverters used to convert direct current generated by photovoltaic modules into alternating current for direct use by users or grid-connected use; Used to obtain the measured current value I in the circuit where the photovoltaic inverter is connected to the user or connected to the grid m实 The measured voltage value U m实 Current collector and voltage collector; and a data analysis module for processing meteorological data and rated parameters; The data analysis module uses the calculation formula to obtain the theoretical power generation power P of the photovoltaic module. llm； Among them, the theoretical power generation power P ll The calculation formula is: G e is the effective irradiation intensity on the slope of the photovoltaic module; ΔT=T m -T ref , T ref is the standard component temperature; ΔG=G e -G ref ; a, b, c are compensation coefficients; e is the base of the natural logarithm, and its value can be 2.71828; and calculate conversion rates The conversion rate The calculation formula is: The data processing module sets the conversion rate threshold when When , the data processing module outputs a normal signal to the control module; when When the data processing module outputs an abnormal signal to the control module.

2. The electric energy metering and monitoring system based on photovoltaic protocol conversion according to claim 1, characterized in that: The front-end data acquisition module includes a meteorological data acquisition unit and an operating parameter acquisition unit; The meteorological data acquisition unit is used to collect meteorological data including solar radiation intensity and photovoltaic module panel surface temperature; The operating parameter acquisition unit is used to acquire the rated parameters of the photovoltaic module including the optimal output current of the photovoltaic module under standard working conditions and the optimal output voltage of the photovoltaic module under standard working conditions.

3. The electric energy metering and monitoring system based on photovoltaic protocol conversion as claimed in claim 2, characterized in that: The solar radiation intensity is acquired by a data acquisition unit in a comprehensive climate database according to the geographical location of the photovoltaic module; the photovoltaic module panel surface temperature is acquired by a temperature sensor installed on the photovoltaic module panel surface.

4. The electric energy metering and monitoring system based on photovoltaic protocol conversion according to claim 1, characterized in that: It also includes a data storage module, which is wirelessly or electrically connected to the front-end data acquisition module; The data storage module is used to store the meteorological data and rated parameters collected by the front-end data collection module.

5. The electric energy metering and monitoring system based on photovoltaic protocol conversion according to claim 1, characterized in that: The control module is also used to receive the solar radiation intensity sent by the front-end data acquisition module in real time and set the lower limit of the solar radiation intensity; When the solar radiation intensity is ≥ the lower limit of the solar radiation intensity, the control module generates a first execution signal and sends it to the front-end data acquisition module, and the front-end data acquisition module collects meteorological data and rated parameters.

6. The electric energy metering and monitoring system based on photovoltaic protocol conversion according to claim 1, characterized in that: Before processing the meteorological data and rated parameters, it also includes: The data preprocessing module forms a board surface temperature data set T, where T = [T1, T2, ...T m …、T M ]; The data preprocessing module obtains the mode in the board surface temperature data set T and marks it as the standard board surface temperature Get the error range of the temperature sensor at this temperature, and convert the PV panel temperature T in the panel temperature data set T m and compare it with the error range under the temperature; if it falls within the error range, the data preprocessing module will m Marked as qualified data; when it does not fall within the error range, the data preprocessing module will m Mark as abnormal data.

7. The electric energy metering and monitoring system based on photovoltaic protocol conversion according to claim 1, characterized in that: The control module is connected to the alarm module; when the data processing module outputs an abnormal signal to the control module, the control module is connected to the alarm module to issue an alarm reminder and arrange operators to troubleshoot the photovoltaic components under the number.

8. The electric energy metering and monitoring system based on photovoltaic protocol conversion according to claim 1, characterized in that: Effective irradiation intensity G e , which is determined by the angle between the photovoltaic panel of the photovoltaic module and the direction of solar radiation.

9. The electric energy metering and monitoring system based on photovoltaic protocol conversion as claimed in claim 1 or 2, characterized in that: The optimal output current and the optimal output voltage of the photovoltaic module under standard operating conditions are obtained from the nameplate of the photovoltaic module.

10. An electric energy metering and monitoring system based on photovoltaic protocol conversion according to any one of claims 1 to 9, characterized in that: The electric energy metering monitoring system includes the following steps: The solar radiation intensity G is collected through the front-end data acquisition module ref , the optimal output current I of the photovoltaic module under standard working conditions mref , the optimal output voltage U of photovoltaic modules under standard working conditions mref And the PV panel surface temperature T m ; A current collector and a voltage collector are set in the circuit where the photovoltaic inverter is connected to the user or the grid to collect the measured current value I m实 The measured voltage value U m实 ; Processing meteorological data and rated parameters with data analysis modules; The data analysis module uses the calculation formula to obtain the theoretical power generation power P of the photovoltaic module. llm And calculate the conversion rate when When , the data processing module outputs a normal signal to the control module; when When , the data processing module outputs an abnormal signal to the control module; The control module is connected to the alarm module; when the data processing module outputs an abnormal signal to the control module, the control module is connected to the alarm module to issue an alarm reminder and arrange operators to troubleshoot the photovoltaic components under the number.

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