Photovoltaic power generation data acquisition system and method

Abstract

The present invention discloses a photovoltaic power generation data acquisition system and method, comprising: a data acquisition unit, an acquisition cycle analysis unit, an acquisition cycle adjustment unit, an acquisition cycle verification unit, an analysis and adjustment unit, and an information output unit. The present invention relates to the field of photovoltaic power generation data acquisition technology, and solves the technical problem that the correctness of data is not reasonably analyzed and a single directional acquisition cycle is used, which affects the accuracy of the collected data. The present invention analyzes the photovoltaic power generation data collected within a preset acquisition cycle to determine whether the collected data has an anomaly. In the event of an anomaly, the acquisition cycle is analyzed to reselect the acquisition cycle, thereby further improving the accuracy of the data and reducing the error caused by using the collected data for judgment.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic power generation data acquisition, and in particular to a photovoltaic power generation data acquisition system and method. Background Art

[0002] Photovoltaic power generation is a technology that uses the photovoltaic effect at the interface of semiconductors to convert light energy directly into electrical energy. It mainly consists of three parts: solar panels, controllers, and inverters, and the main components are made of electronic components.

[0003] According to the patent application number CN202211411934.5, the patent includes a photovoltaic power generation unit, a photovoltaic power generation data acquisition unit, a central data processing terminal, a cloud change operation unit, a malicious tampering identification unit, a cloud data storage library, a power generation prediction unit, a centralized power dispatching unit, a dispatching task adjustment unit and a power generation abnormality monitoring unit.

[0004] The above patent realizes cloud-based data management and processing of photovoltaic power generation data, and performs identity authentication before management, thereby improving management security and efficiency. By adding a scheduling task adjustment unit, it realizes the distribution of photovoltaic power generation to substations in various locations, and adapts to changes in the distribution values ​​of each substation. However, when collecting photovoltaic power generation data, the above patent does not conduct a good verification of the collected data, resulting in errors in the collected data. Secondly, the data collected within the collection period has data anomalies. If the data is still collected according to the collection period, it will cause data errors, which will further affect the overall judgment. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the present invention provides a photovoltaic power generation data acquisition system and method, which solves the problem of no reasonable analysis of the correctness of the data and the use of a single directional acquisition cycle, which affects the accuracy of the collected data.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a photovoltaic power generation data acquisition system, including: a data acquisition unit, an acquisition cycle analysis unit, an acquisition cycle adjustment unit, an acquisition cycle verification unit, an analysis and adjustment unit and an information output unit, and all of the above units are electrically connected.

[0007] The data acquisition unit is used to collect photovoltaic power generation data and transmit it to the collection cycle analysis unit. The photovoltaic power generation data includes the number of photovoltaic modules, operating hours, power generation, voltage, and current. Specifically, when collecting photovoltaic power generation data, there is usually a collection cycle. The system will collect data regularly according to this collection cycle. For example, the collection cycle may be 2 or 3 hours.

[0008] The collection cycle analysis unit is used to obtain the transmitted photovoltaic power generation data, and by analyzing the abnormal characteristics of the photovoltaic power generation data, determine whether there is an abnormality in the current collection cycle, and generate an analysis result. Then, the analysis result is transmitted to the collection cycle adjustment unit. The specific method of generating the analysis result is as follows:

[0009] S1: Obtain the preset collection period, denoted as T, and simultaneously obtain the photovoltaic power generation data within the preset collection period T, where the corresponding photovoltaic power generation data are voltage and current, and establish a coordinate system with time as the horizontal axis and voltage and current as the vertical axis, then graph the voltage and current data within the preset collection period T to obtain a photovoltaic power generation data graph; specifically, the voltage and current within the preset collection period T are recorded using a unit time, and the unit time is determined according to the time value of the preset collection period T. For example, if the preset collection period T is 2 for two hours, the voltage and current values ​​can be recorded once every ten minutes per unit time, and then the recorded data can be graphed.

[0010] S2: Then calculate the maximum peak and minimum peak values ​​corresponding to the photovoltaic power generation data graph, and calculate the difference between the two, and use it as the first feature. Then compare the first feature with the difference preset value. If the first feature is less than the difference preset value, it means that the photovoltaic power generation data collection is normal and the preset collection period T is normal. If the first feature is greater than the difference preset value, it means that the photovoltaic power generation data collection is abnormal, and the difference preset value is set by the operator. Specifically, the difference corresponding to the maximum and minimum values ​​is calculated through the photovoltaic power generation data graph, and the calculated difference is the voltage difference and the current difference. Only when both are satisfied, it means that the collected photovoltaic power generation data is normal. If any one of the two is not satisfied, it indicates an abnormality.

[0011] S3: When the first feature is greater than the preset value, the number of abnormal voltage and current of photovoltaic power generation data is obtained and used as the second feature. At the same time, the second feature is compared with the preset value of the number. If the second feature is greater than the preset value of the number, it indicates that the photovoltaic power generation data collection is abnormal and a cycle adjustment signal is generated. On the contrary, if the second feature is less than the preset value of the number, it indicates that the photovoltaic power generation data collection is normal and no processing is performed. The specific value of the preset value of the number is set by the operator.

[0012] The acquisition cycle adjustment unit is configured to obtain the transmitted cycle adjustment signal, adjust the preset acquisition cycle in combination with the second feature, and generate adjustment information, then verify the adjustment information, perform a secondary analysis on the verification error results to obtain the adjustment cycle information, and transmit the information to the information output unit. The specific method for generating the adjustment cycle information is as follows:

[0013] P1: Obtain the time value corresponding to the preset acquisition period T and record it as T1. At the same time, obtain the time point corresponding to the appearance of the second feature and record this time point as the cutoff point. Then obtain the time starting point corresponding to the preset acquisition period and calculate the time value between the time starting point and the cutoff point and record it as Tc. The time point corresponding to the appearance of the second feature can be understood as: when there is an abnormality in either voltage or current data, obtain its corresponding time point and record this time point as the cutoff point.

[0014] P2: Compare the time value Tc with the preset acquisition cycle time value T1. If Tc ≥ 40% T1, mark the time value Tc as a new acquisition cycle. Conversely, if Tc < 40% T1, perform a secondary analysis on the preset acquisition cycle. The specific method of the secondary analysis is as follows:

[0015] Obtain a normal time period within the preset acquisition time period, denoted as ti, where i = 1, 2, ..., j. Specifically, a normal time period indicates that there is no voltage or current abnormality within the time period. Then obtain its corresponding time value, and screen the normal time periods corresponding to time values ​​greater than 20% T1. If there are multiple normal time periods, select the normal time period corresponding to the maximum time value and use it as the new acquisition period. Specifically, if there is only one normal time period, record the corresponding normal time period as the new acquisition period.

[0016] P3: Get the new collection time period, and at the same time get the next preset time period and record it as the period to be analyzed, and analyze its photovoltaic power generation data. If the photovoltaic power generation data is normal, generate new collection cycle information. If the photovoltaic power generation data is abnormal, get the normal time period of the period to be analyzed, and combine it with the new collection time period to generate new collection cycle information. The specific generation method is as follows:

[0017] When the normal time period corresponding to the period to be analyzed exists within the new acquisition time period, the new acquisition period time is used as the standard and new acquisition period information is generated. When the normal time period corresponding to the period to be analyzed intersects with the new acquisition time period, the two are combined to obtain the new acquisition time period information, which is then transmitted to the information output unit.

[0018] The information output unit is used to obtain the transmitted new collection cycle information and display it to the operator through the display device.

[0019] The present invention provides a photovoltaic power generation data acquisition system and method. Compared with the existing technology, it has the following advantages:

[0020] The present invention analyzes the photovoltaic power generation data collected within a preset collection period to determine whether the collected data has any anomalies. If an anomaly exists, the collection period is reselected by analyzing the collection period, which can further improve the accuracy of the data and reduce the errors caused by using the collected data for judgment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a system block diagram of the present invention;

[0022] Figure 2 This is a schematic diagram of the new acquisition time period of the present invention Figure 1 ;

[0023] Figure 3 This is a schematic diagram of the new acquisition time period of the present invention Figure 2 ;

[0024] Figure 4 This is a diagram of the method of the present invention. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] For example 1, please refer to Figures 1 to 3 The present application provides a photovoltaic power generation data acquisition system, including: a data acquisition unit, an acquisition cycle analysis unit, an acquisition cycle adjustment unit, an acquisition cycle verification unit, an analysis and adjustment unit and an information output unit, and all of the above units are electrically connected.

[0027] The data acquisition unit is used to collect photovoltaic power generation data and transmit it to the collection cycle analysis unit. The photovoltaic power generation data includes the number of photovoltaic modules, operating hours, power generation, voltage, and current. Specifically, when collecting photovoltaic power generation data, there is usually a collection cycle. The system will collect data regularly according to this collection cycle. For example, the collection cycle may be 2 or 3 hours.

[0028] The collection cycle analysis unit is used to obtain the transmitted photovoltaic power generation data, and by analyzing the abnormal characteristics of the photovoltaic power generation data, determine whether there is an abnormality in the current collection cycle, and generate an analysis result. Then, the analysis result is transmitted to the collection cycle adjustment unit. The specific method of generating the analysis result is as follows:

[0029] S1: Obtain the preset collection period, denoted as T, and simultaneously obtain the photovoltaic power generation data within the preset collection period T, where the corresponding photovoltaic power generation data are voltage and current, and establish a coordinate system with time as the horizontal axis and voltage and current as the vertical axis, then graph the voltage and current data within the preset collection period T to obtain a photovoltaic power generation data graph; specifically, the voltage and current within the preset collection period T are recorded using a unit time, and the unit time is determined according to the time value of the preset collection period T. For example, if the preset collection period T is 2 for two hours, the voltage and current values ​​can be recorded once every ten minutes per unit time, and then the recorded data can be graphed.

[0030] S2: Then calculate the maximum peak and minimum peak values ​​corresponding to the photovoltaic power generation data graph, and calculate the difference between the two, and use it as the first feature. Then compare the first feature with the difference preset value. If the first feature is less than the difference preset value, it means that the photovoltaic power generation data collection is normal and the preset collection period T is normal. If the first feature is greater than the difference preset value, it means that the photovoltaic power generation data collection is abnormal, and the difference preset value is set by the operator. Specifically, the difference corresponding to the maximum and minimum values ​​is calculated through the photovoltaic power generation data graph, and the calculated difference is the voltage difference and the current difference. Only when both are satisfied, it means that the collected photovoltaic power generation data is normal. If any one of the two is not satisfied, it indicates an abnormality.

[0031] S3: When the first feature is greater than the preset value, the number of abnormal voltage and current of photovoltaic power generation data is obtained and used as the second feature. At the same time, the second feature is compared with the preset value of the number. If the second feature is greater than the preset value of the number, it indicates that the photovoltaic power generation data collection is abnormal and a cycle adjustment signal is generated. On the contrary, if the second feature is less than the preset value of the number, it indicates that the photovoltaic power generation data collection is normal and no processing is performed. The specific value of the preset value of the number is set by the operator.

[0032] Combined with actual analysis, voltage and current anomalies are expressed as follows: the collected voltage and current data are different from the normal voltage and current corresponding to normal operation. As long as the voltage and current are not equal to the normal voltage and current, the recorded data will be marked as abnormal. Then, the number of abnormal voltages and the number of abnormal currents will be compared with the preset values, and the preset values ​​here are the same. At the same time, if the number of both sets of data is less than the preset value, it indicates that the collection is abnormal.

[0033] The acquisition cycle adjustment unit is configured to obtain the transmitted cycle adjustment signal, adjust the preset acquisition cycle in combination with the second feature, and generate adjustment information, then verify the adjustment information, perform a secondary analysis on the verification error results to obtain the adjustment cycle information, and transmit the information to the information output unit. The specific method for generating the adjustment cycle information is as follows:

[0034] P1: Obtain the time value corresponding to the preset acquisition period T and record it as T1. At the same time, obtain the time point corresponding to the appearance of the second feature and record this time point as the cutoff point. Then obtain the time starting point corresponding to the preset acquisition period and calculate the time value between the time starting point and the cutoff point and record it as Tc. The time point corresponding to the appearance of the second feature can be understood as: when there is an abnormality in either voltage or current data, obtain its corresponding time point and record this time point as the cutoff point.

[0035] P2: Compare the time value Tc with the preset acquisition cycle time value T1. If Tc ≥ 40% T1, mark the time value Tc as a new acquisition cycle. Conversely, if Tc < 40% T1, perform a secondary analysis on the preset acquisition cycle. The specific method of the secondary analysis is as follows:

[0036] Obtain a normal time period within the preset acquisition time period, denoted as ti, where i = 1, 2, ..., j. Specifically, a normal time period indicates that there is no voltage or current abnormality within the time period. Then obtain its corresponding time value, and screen the normal time periods corresponding to time values ​​greater than 20% T1. If there are multiple normal time periods, select the normal time period corresponding to the maximum time value and use it as the new acquisition period. Specifically, if there is only one normal time period, record the corresponding normal time period as the new acquisition period.

[0037] P3: Get the new collection time period, and at the same time get the next preset time period and record it as the period to be analyzed, and analyze its photovoltaic power generation data. If the photovoltaic power generation data is normal, generate new collection cycle information. If the photovoltaic power generation data is abnormal, get the normal time period of the period to be analyzed, and combine it with the new collection time period to generate new collection cycle information. The specific generation method is as follows:

[0038] When the normal time period corresponding to the period to be analyzed exists within the new acquisition time period, the new acquisition period time is used as the standard and new acquisition period information is generated. When the normal time period corresponding to the period to be analyzed intersects with the new acquisition time period, the two are combined to obtain the new acquisition time period information, which is then transmitted to the information output unit.

[0039] Combined with actual analysis, as shown in the attached Figure 2 and attached Figure 3As shown, within the preset collection time value period of the same time value, the normal time period and the new collection time period within the time period are analyzed, and the standard of the new collection time period is determined by adopting a union method.

[0040] The information output unit is used to obtain the transmitted new collection cycle information and display it to the operator through the display device.

[0041] Embodiment 2, as the embodiment 2 of the present invention, differs from embodiment 1 in that the data acquisition unit transmits the photovoltaic power generation data to the analysis and adjustment unit, and the data acquired by the analysis and adjustment unit is the photovoltaic power generation data collected in a new collection cycle.

[0042] The analysis and adjustment unit is used to obtain the transmitted photovoltaic power generation data, and at the same time screen the photovoltaic modules according to their power generation to obtain normal photovoltaic modules and abnormal photovoltaic modules, and then analyze them respectively to obtain analysis information, and transmit the analysis information to the information output unit. The specific method of generating the analysis information is as follows:

[0043] K1: Obtain all photovoltaic modules and label them as n, where n = 1, 2, ..., m. At the same time, obtain the corresponding working hours and total power generation of the photovoltaic modules, which are recorded as Dn and Zn respectively. Then substitute the two into the formula The power Wn of the photovoltaic module is calculated, where a is the influencing factor and the value a=0.64 is calculated based on the actual situation;

[0044] K2: Compare the calculated PV module power Wn with its real-time power Wn1, and classify the PV module corresponding to Wn=Wn1 as a normal PV module, and the PV module corresponding to Wn≠Wn1 as an abnormal PV module. At the same time, the abnormal PV module is labeled as c, where c=1, 2, ..., x; the real-time power can be understood as: the power of the PV module when it is working, and this power is expressed as the power set by the personnel.

[0045] K3: Obtain all abnormal PV modules c, along with their corresponding operating hours Dc and standard power generation Zc. Then, calculate their power, denoted as Wc, and calculate the difference between Wc and the real-time power. This difference is used as the adjustment standard and generates analysis information. Specifically, the standard power generation is the power generation based on the normal operating hours of the PV modules, also known as the power generation index. PV modules that do not meet the power generation index require power adjustment.

[0046] The information output unit is used to obtain the transmitted analysis information and display it to the operator through a display device.

[0047] Embodiment 3: This embodiment includes the entire implementation process of embodiment 1 and embodiment 2.

[0048] See also Figure 4 A photovoltaic power generation data collection method comprises the following steps:

[0049] Step 1: Obtain the collection period of photovoltaic power generation data and determine the correctness of the collection period based on the characteristics of the photovoltaic power generation data;

[0050] Step 2: Filter the photovoltaic power generation data for abnormal collection cycles to obtain normal time periods, and combine them with the preset collection cycles to obtain new collection cycle information;

[0051] Step 3: Analyze the photovoltaic power generation data obtained in the new collection period and classify the photovoltaic power generation components into normal and abnormal according to the power generation;

[0052] Step 4: Then adjust the power of the abnormal photovoltaic power generation component.

[0053] Some of the data in the above formulas are dimensionless and numerically calculated. Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0054] The above embodiments are only used to illustrate the technical method of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A photovoltaic power generation data acquisition system, characterized in that: include: A data acquisition unit is used to collect photovoltaic power generation data and transmit it to the acquisition cycle analysis unit, wherein the photovoltaic power generation data includes: the number of photovoltaic modules, working hours, power generation, voltage and current; The collection cycle analysis unit is used to obtain the transmitted photovoltaic power generation data, and by analyzing the abnormal characteristics of the photovoltaic power generation data, determine whether there is an abnormality in the current collection cycle, and generate an analysis result. Then, the analysis result is transmitted to the collection cycle adjustment unit. The specific method of generating the analysis result is: S1: Obtain a preset collection period, denoted as T, and simultaneously obtain photovoltaic power generation data within the preset collection period T, and establish a coordinate system with time as the horizontal axis and voltage and current as the vertical axis. Then, graph the voltage and current data within the preset collection period T to obtain a photovoltaic power generation data graph; S2: Then, the maximum peak value and the minimum peak value corresponding to the photovoltaic power generation data graph are calculated, and the difference between the two is calculated, and the difference is used as the first feature. Then, the first feature is compared with a preset difference value. If the first feature is less than the preset difference value, it indicates that the photovoltaic power generation data collection is normal and the preset collection period T is normal. If the first feature is greater than the preset difference value, it indicates that the photovoltaic power generation data collection is abnormal, and the preset difference value is set by the operator. S3: If the first feature is greater than a preset value, the number of abnormal voltage and current occurrences in the photovoltaic power generation data is obtained and used as the second feature. The second feature is compared with the preset number of occurrences. If the second feature is greater than the preset number of occurrences, it indicates that the photovoltaic power generation data collection is abnormal, and a cycle adjustment signal is generated. Conversely, if the second feature is less than the preset number of occurrences, it indicates that the photovoltaic power generation data collection is normal, and no processing is performed. an acquisition cycle adjustment unit, configured to obtain the transmitted cycle adjustment signal, adjust the preset acquisition cycle in combination with the second feature and generate adjustment information, then verify the adjustment information, perform a secondary analysis on verification errors to obtain adjustment cycle information, and transmit the information to the information output unit; The analysis and adjustment unit is used to obtain the transmitted photovoltaic power generation data, and at the same time screen the photovoltaic modules according to their power generation to obtain normal photovoltaic modules and abnormal photovoltaic modules, and then analyze them respectively to obtain analysis information, and transmit the analysis information to the information output unit.

2. A photovoltaic power generation data acquisition system according to claim 1, characterized in that: The acquisition cycle adjustment unit generates the adjustment cycle information in the following manner: P1: Get the time value corresponding to the preset acquisition period T, record it as T1, and at the same time get the time point corresponding to the appearance of the second feature, and record this time point as the cutoff point. Then get the time starting point corresponding to the preset acquisition period, and calculate the time value between the time starting point and the cutoff point, record it as Tc; P2: Compare the time value Tc with the preset acquisition cycle time value T1. If Tc ≥ 40% T1, mark the time value Tc as a new acquisition cycle. Conversely, if Tc < 40% T1, perform a secondary analysis on the preset acquisition cycle. P3: Obtain a new collection time period, and at the same time obtain its next preset time period and record it as the period to be analyzed, and analyze its photovoltaic power generation data. If the photovoltaic power generation data is normal, generate new collection cycle information. Conversely, if the photovoltaic power generation data is abnormal, obtain the normal time period of the period to be analyzed, and combine it with the new collection time period to generate new collection cycle information.

3. A photovoltaic power generation data acquisition system according to claim 2, characterized in that: The specific method of the secondary analysis in P2 is: Obtain the normal time period within the preset acquisition time period, denoted as ti, where i = 1, 2, ..., j, then obtain its corresponding time value, and filter the normal time periods corresponding to time values ​​greater than 20% T1. If there are multiple normal time periods, select the normal time period corresponding to the maximum time value and use it as the new acquisition period.

4. A photovoltaic power generation data acquisition system according to claim 2, characterized in that: The method for generating new acquisition cycle information in P3 is: When the normal time period corresponding to the period to be analyzed exists within the new acquisition time period, the new acquisition period time is used as the standard and new acquisition period information is generated. When the normal time period corresponding to the period to be analyzed intersects with the new acquisition time period, the two are combined to obtain the new acquisition time period information, which is then transmitted to the information output unit.

5. The photovoltaic power generation data acquisition system according to claim 1, characterized in that: The specific manner in which the analysis and adjustment unit generates analysis information is as follows: K1: Obtain all photovoltaic modules and label them as n, where n = 1, 2, ..., m. At the same time, obtain the corresponding working hours and total power generation of the photovoltaic modules, which are recorded as Dn and Zn respectively. Then substitute the two into the formula The power Wn of the photovoltaic module is calculated, where a is the influencing factor and the value a=0.64 is calculated based on the actual situation; K2: Compare the calculated PV module power Wn with its real-time power Wn1, and classify the PV module corresponding to Wn=Wn1 as a normal PV module, and classify the PV module corresponding to Wn≠Wn1 as an abnormal PV module. At the same time, the abnormal PV module is labeled as c, where c=1, 2, ..., x; K3: Obtain all abnormal PV modules c, and obtain their corresponding working hours Dc and standard power generation Zc. Then calculate their power Wc, and calculate the difference between the power Wc and the real-time power. At the same time, the difference is used as the adjustment standard and generate analysis information.

6. The photovoltaic power generation data acquisition system according to claim 1, characterized in that: The information output unit is used to obtain the transmitted analysis information and new acquisition cycle information, and display them to the operator through a display device.

7. The photovoltaic power generation data acquisition system according to claim 1, characterized in that: The data acquisition unit, the acquisition cycle analysis unit, the acquisition cycle adjustment unit, the acquisition cycle verification unit, the analysis and adjustment unit and the information output unit are electrically connected.

8. A method for collecting data of a photovoltaic power generation system according to any one of claims 1 to 7, characterized in that: The method specifically comprises the following steps: Step 1: Obtain the collection period of photovoltaic power generation data and determine the correctness of the collection period based on the characteristics of the photovoltaic power generation data; Step 2: Filter the photovoltaic power generation data for abnormal collection cycles to obtain normal time periods, and combine them with the preset collection cycles to obtain new collection cycle information; Step 3: Analyze the photovoltaic power generation data obtained in the new collection period and classify the photovoltaic power generation components into normal and abnormal according to the power generation; Step 4: Then adjust the power of the abnormal photovoltaic power generation component.

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