System and method for judging whether self-generating and self-using photovoltaic user affects power factor or not

Abstract

The invention discloses a system and method for judging whether a self-generating and self-using photovoltaic user affects a power factor, and the system comprises a source data collection module, a source data processing module and a result output module, the source data collection module is used for collecting the power utilization data of the photovoltaic user, and the power utilization data comprises active power, reactive power, voltage and current; and the source data processing module is connected with the source data acquisition module and is used for analyzing the acquired power consumption data, calculating a power factor and judging whether the power factor is in a normal range. The problem that after a project is put into production, a user is penalty due to an unqualified power factor is avoided, and the bad influence on economy and society is effectively reduced; the working efficiency can be effectively improved, waste of manpower, material resources and financial resources is reduced, and a judgment result and an early warning signal are output in time through the result output module.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic power generation technology, and particularly to a system and method for judging whether a self-consumption photovoltaic user affects the power factor. Background Art

[0002] With the continuous development and popularization of photovoltaic power generation technology, more and more users choose to install self-consumption photovoltaic systems. However, the access of photovoltaic systems may affect the power factor of the power grid. The power factor is an important indicator to measure the efficiency of the power system. A low power factor will lead to problems such as increased power grid losses and voltage fluctuations, and at the same time will also increase the electricity cost of users.

[0003] In the field of photovoltaic grid-connected technology, self-consumption distributed photovoltaic systems are widely used due to their high-efficiency energy utilization characteristics. However, the coupling effect of the non-linear output characteristics of photovoltaic inverters and the dynamic changes of user loads results in complex fluctuation characteristics of the power factor at the Point of Common Coupling (PCC), which directly affects the power quality of the power grid and the electricity economy of users (the power grid levies punitive electricity charges on users with unqualified power factors). In the access design, it is easy to ignore the problem that the power factor does not meet the requirements, or based on the determined installed capacity, use professional calculation software to calculate whether the PCC power factor will be greater than or equal to 0.95 after the project is grid-connected. It is impossible to obtain the installed capacity under qualified power factor at the initial stage of design, and it is easy to ignore the problem that the power factor does not meet the requirements, resulting in the problem that users are fined due to unqualified power factors after the project is put into production, causing high economic losses and poor social impacts, and the review period is long, consuming a lot of manpower, material resources and financial resources, and the work efficiency is low. Therefore, a system and method for quickly judging whether a self-consumption photovoltaic user affects the power factor are provided to solve the above problems. Summary of the Invention

[0004] To solve the problems of high cost and low efficiency in the existing judgment method, the technical solution adopted by the present invention to solve the technical problems is: a system for judging whether a self-consumption photovoltaic user affects the power factor, which includes a source data acquisition module, a source data processing module, and a result output module. The source data acquisition module is used to collect the electricity consumption data of photovoltaic users, including active power, reactive power, voltage, and current. The source data processing module is connected to the source data acquisition module and is used to analyze the collected electricity consumption data, calculate the power factor, and judge whether the power factor is within the normal range. The result output module is connected to the source data processing module and is used to output the judgment result. When the power factor is not within the normal range, a warning signal is issued.

[0005] As a preferred technical solution of the present invention, the source data acquisition module includes a user electricity bill ORC recognition and processing sub-module (program), and the user electricity bill ORC recognition and processing sub-module (program) is used to collect user type, user name, active power consumption, reactive power consumption, and power factor data.

[0006] As a preferred technical solution of the present invention, the source data processing module includes a data processing unit and a judgment unit. The data processing unit is used to perform reasoning calculations on the collected data, and the judgment unit is used to calculate the power factor based on the processed data and compare it with a preset normal range.

[0007] As a preferred technical solution of the present invention, the result outputs a warning interval graph corresponding to the installed capacity.

[0008] A method for judging whether a self-consumption photovoltaic user affects the power factor includes the following steps:

[0009] Step S1: Collect the electricity consumption data of the photovoltaic user through the data acquisition module;

[0010] Step S2: Transmit the collected electricity consumption data to the source data processing module, and the source data processing module processes and analyzes the data to calculate the power factor;

[0011] Step S3: Judge whether the calculated power factor is within the normal range, and send a warning signal through the result output module, and conduct further analysis and processing.

[0012] As a preferred technical solution of the present invention, further, in step S2, the formula for calculating the power factor is: power factor = active power / apparent power, where active power = (electricity information - peak) + (electricity information - valley) + (electricity information - flat) + (electricity information - trough), and apparent power = √(active power 2 + reactive power 2 ).

[0013] As a preferred technical solution of the present invention, further in step S3, the analysis and processing include: calculating and scanning the range of 5% to 400% of the installed capacity of the proposed photovoltaic installation, analyzing the predicted power factor values within the installed capacity range, and taking corresponding measures according to the results.

[0014] As a preferred technical solution of the present invention, the reasons for the abnormality include photovoltaic system failures and load changes.

[0015] As a preferred technical solution of the present invention, taking corresponding measures according to the reasons includes adjusting the operating parameters of the photovoltaic system and optimizing the reactive power configuration.

[0016] The present invention has the following advantages: The present invention can give the installed capacity under qualified power factor in combination with the actual situation of the factory area at the initial stage of design, avoiding the problem that users are fined due to unqualified power factor after the project is put into production, and effectively reducing the negative impacts on the economy and society; it can effectively improve work efficiency and reduce the waste of manpower, material resources and financial resources;

[0017] By outputting the judgment result and early warning signal in time through the result output module, it can quickly, simply and at low cost judge whether the self-consumption photovoltaic user affects the power factor, providing an effective decision-making basis for users and grid operators, and having a wide application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of the calculation logic flow of the preferred embodiment of the present invention;

[0019] Figure 2 is a schematic diagram of the import source data logic flow of the preferred embodiment of the present invention;

[0020] Figure 3 is a schematic diagram of the source data processing logic flow of the preferred embodiment of the present invention;

[0021] Figure 4 is a schematic diagram of the method of the preferred embodiment of the present invention.

[0022] Figure 5 is a data diagram of the calculation example of the preferred embodiment of the present invention.

[0023] Figure 6 is a schematic diagram of the power factor after the photovoltaic is put into production of the preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention may be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0025] In order to more clearly understand the above objects, features and advantages of the present invention, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0026] Please refer to Figures 1 - 6, the system for the present invention to determine whether self-consumption PV users affect the power factor includes a source data acquisition module, a source data processing module, and a result output module. The source data acquisition module is used to collect the electricity consumption data of PV users, including active power, reactive power, voltage, and current. The source data processing module is connected to the source data acquisition module and is used to analyze the collected electricity consumption data, calculate the power factor, and determine whether the power factor is within the normal range. The result output module is connected to the source data processing module and is used to output the judgment result. When the power factor is not within the normal range, a warning signal is issued.

[0027] The user electricity bill ORC recognition and processing sub-module (program), and the user electricity bill ORC recognition and processing sub-module (program) is used to collect user type, user name, active electricity, reactive electricity, and power factor data. The source data processing module includes a data processing unit and a judgment unit. The data processing unit is used to perform reasoning calculations on the collected data, and the judgment unit is used to calculate the power factor based on the processed data and compare it with the preset normal range, and output the warning interval graph corresponding to the installed capacity.

[0028] The method for determining whether self-consumption PV users affect the power factor includes the following steps:

[0029] Step S1: Collect the electricity consumption data of PV users through the data acquisition module; including active power, reactive power, voltage, current, etc.

[0030] Step S2: Transmit the collected electricity consumption data to the source data processing module, and the source data processing module processes and analyzes the data to calculate the power factor;

[0031] Step S3: Determine whether the calculated power factor is within the normal range, and issue a warning signal through the result output module, and perform further analysis and processing.

[0032] In step S2, the formula for calculating the power factor is: power factor = active power / apparent power, where active power = (electricity information - peak) + (electricity information - valley) + (electricity information - flat) + (electricity information - trough), and apparent power = √(active power 2 + reactive power 2 )

[0033] In step S3, the analysis and processing include: calculating and scanning the range of 5% to 400% of the installed capacity of the proposed PV installation, analyzing the predicted power factor value within the installed capacity range, and taking corresponding measures according to the results. Taking corresponding measures according to the reasons includes adjusting the operating parameters of the PV system and optimizing the reactive power device.

[0034] Specifically, when the present invention is in use, the source data acquisition unit is deployed as follows: An intelligent electricity meter is installed at the output end of the photovoltaic system to collect the power generation power, and another intelligent electricity meter is installed at the user's power inlet to collect the power consumption power. At the same time, a current transformer and a voltage sensor are respectively installed at the grid access point to measure the voltage and current data.

[0035] A 4G wireless transmission module is adopted to transmit the data obtained by the source data acquisition unit to the server where the source data processing module is located. The time interval for data transmission is set to 5 seconds to ensure the real-time nature of the data.

[0036] The data analysis and judgment program is run on the server. The preset normal power factor range is 0.9 - 1.0, and the program processes the received data and calculates the power factor according to the established algorithm.

[0037] The corresponding APP is installed on the user's mobile phone, and a monitoring platform is set up in the power management center. When the power factor is abnormal, the APP and the monitoring platform will immediately pop up an alarm message and display the relevant data.

[0038] During the actual operation process, if the calculated power factor at a certain moment is 0.85, which is lower than the lower limit of the normal range, the system immediately issues an alarm through the result output unit, prompting the user and the power management personnel that the power factor is abnormal. By analyzing the power generation power and power consumption power data, the power management personnel find that it is due to the user adding a new high-power device, resulting in a sudden increase in the power consumption load, thus affecting the power factor.

[0039] Specifically, refer to Figure 1 , Figure 2 and Figure 3 In quickly judging whether the self-consumption photovoltaic user affects the power factor:

[0040] Import source data: Input the installed capacity or (house area + photovoltaic panel model (default is 600Wp)), which is only applicable to self-consumption users or self-consumption users with surplus power fed into the grid, and electricity bill data (1 - 3 months).

[0041] The matching rules of the source data processing module are as follows:

[0042] (1) Table header - user number;

[0043] (2) Table header - settlement account number;

[0044] (3) Table header - settlement account name;

[0045] (4) Basic information - transmission and distribution price category;

[0046] (5) Basic information - user category; [[ID=4,3]]

[0047] (6) Basic information - electricity usage start time;

[0048] (7) Basic information - End time of power consumption;

[0049] (8) Electricity charge information - Total reactive power;

[0050] (9) Electricity charge information - Power factor;

[0051] (10) Electricity quantity information - Peak;

[0052] (11) Electricity quantity information - Shoulder peak;

[0053] (12) Electricity quantity information - Flat;

[0054] (13) Electricity quantity information - Valley;

[0055] Calculation rule 1 (scale conversion) of the source data processing module:

[0056] 1. Fuzzy estimation method: Installed capacity (kWp) = Roof area (m²) × 0.2

[0057] 2. Precise estimation method: Installed capacity (kWp) = Roof area (m²) × 0.8 / Area of a single module;

[0058] Calculation rule 2 (photovoltaic output estimation):

[0059] Monthly photovoltaic active power quantity Ph (kW·h) = Installed capacity (kWp) × 0.8 × 1200 (h) / 12

[0060] Monthly photovoltaic reactive power quantity Qh (kVar·h) = Ph / tan(arccos(0.98));

[0061] Calculation rule 3 (analyzing the influence range of scale on reactive power):

[0062] 1. Total active power = (Electricity quantity information - Peak) + (Electricity quantity information - Shoulder peak) + (Electricity quantity information - Flat) + (Electricity quantity information - Valley)

[0063] 2. Fluctuation coefficient = Average monthly total active power / Number of months

[0064] Judgment rule:

[0065] 1. Influential range

[0066] 2. Non - influential range

[0067] The calculation parameters of the source data processing module are as follows in the table:

[0068] Component Model Wp <![CDATA[Component area m 2 > 500 1.9 550 2.1 600 2.3 650 2.55 700 2.7

[0069] Finally, output the result.

[0070] Refer toFigure 5 , Figure 6 , based on the calculation example of this solution, it includes the following data parameters:

[0071] Read the following data from the electricity bill: electricity consumption type, active power consumption (kW·h), reactive power consumption (kW·h), power factor;

[0072] Obtain the following data through calculation or user input;

[0073] Perform a step-by-step calculation (step size 1%) on the range of (5% - 400%) of the installed capacity to generate statistical data;

[0074] Calculation multiple;

[0075] Photovoltaic installed capacity (kW);

[0076] Estimation of active power consumption;

[0077] Estimation of reactive power consumption;

[0078] Active power estimation of the electric meter (after photovoltaic installation);

[0079] Reactive power estimation of the electric meter (after photovoltaic installation);

[0080] Power factor after photovoltaic installation;

[0081] Draw the conclusion: The early warning interval for the photovoltaic capacity installed in the factory area is 1000kW - 6500kW; the installed capacity of this project is 2000kW which is within the interval, so reactive power needs to be regulated ( Figure 5 , Figure 6 Some data display is given).

[0082] The above shows and describes the basic principles, main features and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic features of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0083] Other parts not detailed in the present invention belong to the prior art, so they will not be elaborated here.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system for determining whether self-consumption photovoltaic users affect the power factor, comprising, characterized in that, The source data acquisition module, the source data processing module, and the result output module. The source data acquisition module is used to collect the electricity consumption data of photovoltaic users, including active power, reactive power, voltage, and current. The source data processing module is connected to the source data acquisition module and is used to analyze the collected electricity consumption data, calculate the power factor, and determine whether the power factor is within the normal range. The result output module is connected to the source data processing module and is used to output the judgment result. When the power factor is not within the normal range, a warning signal is sent.

2. The system for determining whether a self-consumption photovoltaic user affects the power factor according to claim 1, wherein The source data acquisition module includes a user electricity bill ORC recognition and processing sub-module, which is used to collect user type, user name, active electricity consumption, reactive electricity consumption, and power factor data.

3. The system for determining whether a self-consumption photovoltaic user affects the power factor as described in claim 1, wherein The source data processing module includes a data processing unit and a judgment unit. The data processing unit is used to perform inference calculations on the collected data, and the judgment unit is used to calculate the power factor based on the processed data and compare it with the preset normal range.

4. The system for determining whether a self-consumption PV user affects the power factor according to claim 1, characterized in that, The result outputs the warning interval graph corresponding to the installed capacity.

5. The method for judging whether a self-consumption photovoltaic user affects the power factor based on the system according to any one of claims 1-4, characterized in that, The method includes the following steps: Step S1: Collect the electricity consumption data of photovoltaic users through the data acquisition module; Step S2: Transmit the collected electricity consumption data to the source data processing module, and the source data processing module processes and analyzes the data to calculate the power factor; Step S3: Determine whether the calculated power factor is within the normal range, send a warning signal through the result output module, and perform further analysis and processing.

6. The method for determining whether a self-consumption PV user affects the power factor according to claim 5, wherein, In step S2, the formula for calculating the power factor is: Power factor = Active power / Apparent power, where Active power = (Electricity information - Spike) + (Electricity information - Peak) + (Electricity information - Flat) + (Electricity information - Valley), and Apparent power = √(Active power² + Reactive power²).

7. The method for determining whether a self-consumption PV user affects the power factor according to claim 5, wherein In step S3, the analysis and processing include: calculating and scanning the range of 5% - 400% of the installed capacity of the planned photovoltaic installation, analyzing the predicted power factor value within the installed capacity range, and taking corresponding measures according to the results.

8. The method for determining whether a self-consumption photovoltaic user affects the power factor according to claim 7, characterized in that, The reasons for the abnormality include photovoltaic system failures and load changes.

9. The method for determining whether a self-consumption PV user affects the power factor as claimed in claim 7, wherein Taking corresponding measures according to the reasons includes adjusting the operating parameters of the photovoltaic system and optimizing the reactive power configuration.

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