JP6320240B2 - Solar power system - Google Patents

Description

  The present invention relates to a photovoltaic power generation system that interconnects AC power with a commercial power source.

  Solar power generation systems have become widespread due to the low price of solar cell modules. In particular, in Japan, the total purchase system of renewable energy strongly encourages the spread of solar power generation systems. With the widespread use of solar power generation systems, the scale of solar power generation systems is increasing, and the number of solar power generation systems having a plurality of sets of solar cell arrays and power conditioners is increasing. Conventionally, a photovoltaic power generation system is generally provided with a photovoltaic power generation display device that displays generated power information, sold power information, purchased power information, and consumed power information. Along with this trend, photovoltaic power generation display devices are also required to have functions and performance corresponding to large-capacity power generation. In Japan, electric power sold is surplus electric power sold in the background of a system for purchasing all renewable energy, and electric power purchased is, for example, electric power purchased from an electric power company.

  For example, Patent Document 1 states that “the operation state such as the power generated by the photovoltaic power generation system and the amount of accumulated power generation, and the power situation such as the power consumption in the house, the purchased power, and the sold power are more easily understood. In order to provide a photovoltaic power generation system having a display means that can be transmitted to a person ", in a photovoltaic power generation system that converts the direct current output of the solar cell 1 into alternating current and is connected to the commercial power source 6, The generated power measuring means 3b for measuring the power generated by the solar power generation, the buying and selling power measuring means 7 for measuring the power supplied from the commercial power source 6 or the reverse power to the commercial power source 6, and the measured generated power and sold power A photovoltaic power generation system is disclosed that is configured to include display means 5 that has a dot matrix display 5b that displays or displays measured generated power and purchased power.

JP 2004-12376 A

  However, according to the above-described conventional technology, when a plurality of power conditioners are connected, the generated power information is sequentially obtained from each power conditioner by communication. Therefore, the generated power information is obtained from all the power conditioners. It takes time to get it. For this reason, a time lag occurs between the power purchase and sale information acquired from the power sensor, and if there is a fluctuation in generated power due to changes in solar radiation or a change in buy and sell power due to changes in load, there will be a shift in the calculation of power consumption. There was a problem. The buying and selling power information is information indicating both the selling power and the buying power.

  The present invention has been made in view of the above, and in a photovoltaic power generation display device of a photovoltaic power generation system to which a plurality of power conditioners are connected, while acquiring generated power information from all the power conditioners. To obtain a photovoltaic power generation system capable of calculating and displaying generated power, sold power, purchased power, and consumed power while suppressing errors even when the generated power or consumed power fluctuates With the goal.

In order to solve the above-described problems and achieve the object, the present invention provides a solar cell array in which a plurality of solar cell modules are arranged, and a plurality of power conditioners that convert DC power from the solar cell array into AC power. A solar power generation system that interconnects the AC power with a commercial power source, and measures current of the purchased power supplied from the commercial power source and the sold power flowing backward to the commercial power source A power consumption calculation unit that obtains power generation information from the power conditioner and power purchase / purchase information based on a detection value of the current sensor, calculates a power consumption from the power generation information and the power purchase information, and the power consumption A photovoltaic power generation display device including a power consumption display unit for displaying, wherein the power consumption is the sum of the generated power and the power condition of the purchased power. From the sum of the arithmetic mean values of per conditioner is calculated by the difference obtained by subtracting the arithmetic mean of the per power conditioner of the power selling power, a plurality of the power conditioner, a plurality of the The first power conditioner group composed of power conditioners and the second power conditioner group composed of a plurality of power conditioners, and the power consumption displayed on the power consumption display unit is The second power conditioner having the generated power of the first power conditioner group having the latest generated power at the time of display and the generated power before being updated to the latest generated power at the time of display. The power purchase obtained in synchronism with the acquisition of the generated power information of each power conditioner and the sum of the generated power of the group Is calculated by using the force and the power selling power, the power consumption to be displayed on the power display section, characterized in that it is updated by a predetermined distance.

  According to the present invention, in the photovoltaic power generation display device of the photovoltaic power generation system to which a plurality of power conditioners are connected, the generated power or the consumed power fluctuates while the generated power information is acquired from all the power conditioners. Even in such a case, it is possible to calculate and display the generated power, the sold power, the purchased power, and the power consumption while suppressing the error.

The figure which shows the structure of the solar energy power generation system concerning embodiment The figure which shows an example of the calculation method of a power consumption calculating part Flow chart showing an example of calculation procedure of power consumption calculation unit The figure explaining the procedure to secure the real-time property of generated power, sold power and purchased power

  Embodiments of a photovoltaic power generation system according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment.
FIG. 1 is a diagram showing a configuration of an embodiment of a photovoltaic power generation system according to the present invention. 1 includes a solar cell array 1, a power conditioner 2, a distribution board 3, an electric device 4, an output line 5, a measuring device 6, a monitoring device 7, a communication line 8, a current sensor 9, and a power line. 10 is provided. In the solar cell array 1, for example, a plurality of solar cell modules installed on the roof of a building are connected in series or in parallel, receive sunlight to generate power, and generate DC power. A power conditioner 2 is connected to each solar cell array 1. The power conditioner 2 converts the DC power generated in the solar cell array 1 into AC power. An output line 5 of the power conditioner 2 is connected to the distribution board 3. The AC power converted by the power conditioner 2 is consumed by the electric device 4 via the branch breaker in the distribution board 3. The electric device 4 is, for example, a home appliance installed in a house. Outputs of a plurality of power conditioners are connected to a commercial power source by a distribution board 3.

  When the amount of generated power in the solar cell array 1 is small or cannot be generated, the power of the commercial power source connected to the distribution board 3 is supplied to each electrical device 4 via the distribution board 3. In addition, when there is little generated electric power, the time of cloudy weather or rainy weather can be illustrated. When power generation is not possible, the night can be exemplified. Conversely, when the amount of generated power is greater than the total power consumed by the electrical device 4, surplus power is generated. Surplus power is reversely flowed to the commercial power supply via the distribution board 3. In the present specification, the supply of power from a commercial power source to each electric device 4 via the former distribution board 3 is called power purchase, and the reverse flow of surplus power to the commercial power source is called power sale.

  The measuring device 6 receives the generated power information from the power conditioner 2 via the communication line 8 between the power conditioner 2 and the measuring device 6. The current sensor 9 mounted in the distribution board 3 is a current sensor for detecting trading power that measures the value of current flowing between the commercial power supply and the distribution board 3 and the direction of the current. The measuring device 6 collects the current value at the time of power sale or the current value at the time of power purchase from the measurement result of the current sensor 9.

  The power line 10 connects the distribution board 3 and the measuring device 6. The measuring device 6 is supplied with power as a power source from the distribution board 3 through the power line 10. In the distribution board 3 and the measurement device 6, for example, the measurement device 6 is connected to an outlet wired from the one branch breaker in the distribution board 3, or the measurement device 6 is directly connected to the secondary side of the one branch breaker. Being connected. The measuring device 6 measures the voltage value of the commercial power supply from the power line 10 and obtains the power sale power data or the power purchase power data by calculation with the detected current value of the current sensor 9.

  The monitor device 7 communicates with the measurement device 6 through the measurement device connection unit 70, and the generated power and the sale / purchase of the power conditioner 2 by the generated power acquisition unit 71 and the purchase / purchase power acquisition unit 73 in accordance with the input from the measurement device 6. Get power. The power consumption calculation unit 75 calculates power consumption C. Data obtained by the generated power acquisition unit 71, the purchased / sold power acquisition unit 73, and the consumed power calculation unit 75 are transmitted to the generated power display unit 72, the purchased / sold power display unit 74, and the consumed power display unit 76. Displayed in the form of power data or graphs. The measuring device 6 and the monitor device 7 exchange data with each other by wired communication.

  Further, the monitor device 7 calculates the power consumption C by the power consumption calculation unit 75 using the generated power and the trading power acquired from the generated power acquisition unit 71 and the trading power acquisition unit 73. The monitor device 7 generates power generation information, power sale power information, power purchase power information and power consumption information of each electric device 4 obtained by measurement or calculation, a power generation display 72, a power purchase display 74 and power consumption display. Displayed on the part 76.

  FIG. 2 is a diagram illustrating an example of a calculation method of the power consumption calculation unit 75. FIG. 2 illustrates a case where the power consumption calculation unit 75 calculates power consumption information using generated power information, sold power information, and purchased power information in a solar power generation system including 10 power conditioners. doing.

  In FIG. 2, the ten power conditioners are denoted as power conditioners 2A, 2B, 2C, 2D, 2E, 2F, 2G, 2H, 2I, and 2J, respectively. First, the generated power G1 of the power conditioner 2A is acquired, and the selling power B1 and the purchased power K1 are acquired in synchronization with the power conditioner 2A. Thereafter, similarly, the power generation power G2 of the power conditioner 2B is acquired, the power sale power B2 and the power purchase power K2 are acquired in synchronization with the power conditioner 2B, and the power conditioner 2J is sequentially acquired. After acquiring the generated power G10, the sold power B10 and the purchased power K10 of the power converter 2J, the process returns to the acquisition of the generated power G1, the sold power B1 and the purchased power K1 of the power converter 2A, and this is repeated. The generated power G1 to G10 is stored in a memory in the generated power acquisition unit 71 of the monitor device 7, and the sold power B1 to B10 and the purchased power K1 to K10 are stored in the trading power acquisition unit 73 of the monitor device 7. Stored in the memory.

  And if the said acquired electric power generation G1-G10, electric power sales B1-B10, and electric power purchase K1-K10 are used, electric power consumption C is the sum total (SIGMA) G of electric power generation G1-G10, and the phase of electric power purchase K1-K10. It is calculated by the difference obtained by subtracting the arithmetic average ΣB / 10 of the electric power sales B1 to B10 from the sum of the arithmetic average ΣK / 10. That is, C = ΣG + ΣK / 10−ΣB / 10. When the number of power conditioners is n and generalized, the power consumption C is expressed by the following equation (1). Here, the generated power can be adjusted to a value for one cycle by using the sum total and the trading power by using an arithmetic average. This is because the power generated from each power conditioner is only for each power conditioner, so the power generated by the entire photovoltaic power generation system is the sum of the power generated by each power conditioner. While collecting information from each power conditioner, that is, the generated power in one cycle, the sold power or purchased power is collectively measured as a whole value on the distribution board connected to the commercial power source, And since it is obtained in synchronism with the generated power acquisition of each power conditioner, it is because the buying and selling power can obtain 10 whole values in one cycle.

  FIG. 3 is a flowchart illustrating an example of a calculation procedure of the power consumption calculation unit 75. First, the process is started (S1), and the generated power acquisition unit 71 acquires the generated power G1 to Gn (S2), while the trading power acquisition unit 73 acquires the sold power B1 to Bn and the purchased power K1 to Kn. (S3). The power consumption calculation unit 75 obtains the generated power G1 to Gn, the sold power B1 to Bn, and the purchased power K1 to Kn, calculates ΣG, ΣB / n, and ΣK / n (S4), ΣG, ΣB / Power consumption C is calculated from n and ΣK / n (S5), and the process is terminated (S6). As described above, according to the present invention, in the photovoltaic power generation display device of the photovoltaic power generation system to which a plurality of power conditioners are connected, the generated power or the consumed power while acquiring the generated power information from all the power conditioners. Even if there is a change in the power consumption, it is possible to calculate and display the generated power, the sold power, the purchased power, and the consumed power while suppressing the error.

  FIG. 4 is a diagram illustrating a procedure for securing real-time properties of generated power, sold power, and purchased power.

  In a photovoltaic power generation system including a plurality of power conditioners, when the calculated power consumption C is displayed on the screen after acquiring the generated power, the sold power, and the purchased power of all the power conditioners, the update interval of the screen display is long. Thus, real-time performance is impaired. In addition, the display may feel uncomfortable due to the loss of real-time display. Therefore, in the present embodiment, a divided display is performed instead of updating the screen after data acquisition of all the inverters.

  In FIG. 4 (A), 10 power conditioners are provided, and it takes 5/4 seconds to acquire data from one power conditioner, and 5/4 seconds to transmit / receive other data. An example is shown in which other data is transmitted / received after data acquisition from the fourth power conditioner and after data acquisition from the sixth power conditioner, and it takes 15 seconds to acquire data from all the power conditioners. Here, the screen display is performed at intervals of 5 seconds. In other words, after the data acquisition of the first to fourth inverters is completed, the screen is displayed, other data is transmitted and received, and the acquisition of data for the fifth inverter and the sixth inverter is completed. Screen display is performed later, and finally screen display is performed after data acquisition of the seventh to tenth inverters is completed. By repeating such an operation, the display can be updated at intervals of 5 seconds.

  At this time, for example, at the time of data acquisition of the first to fourth power conditioners, the calculation of the power consumption C is performed by calculating the generated power of the first to fourth power conditioners acquired this time and the last five acquired power conditioners. By using the sum of the generated power of the 10th power conditioner from the first, and the arithmetic average data of the power sales and power purchased in synchronization with the power generation information acquisition of each power conditioner, Is possible.

  In addition, although the case where the number of power conditioners is 10 is illustrated here, this invention is not limited to this. FIG. 4B shows a measurement order according to the number of power conditioners. However, the description when the number of power conditioners is one is omitted.

  If the number of inverters is two, acquire the data for the first inverter after acquiring the data for the first inverter, and then acquire the data for the first inverter again. Get this and repeat.

  If the number of inverters is 3, acquire the data of the second inverter after acquiring the data of the first inverter, and then acquire the data of the third inverter The data of the first inverter is acquired again and this is repeated.

  In this way, by acquiring data sequentially from the inverter, and using the latest data of each inverter when displaying the screen, shortening the update interval of the screen display reduces the real-time performance of the screen display. Can be secured.

  In the present embodiment, the communication between the power conditioner 2 and the measurement device 6 and the communication between the measurement device 6 and the monitor device 7 are wired communication. However, the present invention is not limited to this, and wireless communication is possible. You may carry out by communication.

  As described above, according to the present invention, in the photovoltaic power generation display device of the photovoltaic power generation system to which a plurality of power conditioners are connected, the screen is not updated after data acquisition of all the power conditioners. While maintaining the real-time property by performing divided display, even if the generated power or power consumption fluctuates, the generated power, sold power, purchased power, and consumed power are calculated while suppressing errors. There is an effect that it is possible to display.

  DESCRIPTION OF SYMBOLS 1 Solar cell array, 2 Power conditioner, 3 Power distribution board, 4 Electric equipment, 5 Output line, 6 Measuring apparatus, 7 Monitor apparatus, 8 Communication line, 9 Current sensor, 10 Power line, 70 Measuring apparatus connection part, 71 Power generation A power acquisition unit, 72 a generated power display unit, 73 a trading power acquisition unit, 74 a trading power display unit, a 75 power consumption calculation unit, and a 76 power consumption display unit.

Claims (1)

A solar cell array in which a plurality of solar cell modules are arranged, and a solar power generation system having a plurality of power conditioners that convert DC power from the solar cell array into AC power, and grid-connecting the AC power to a commercial power source Because
A current sensor for measuring the electric power purchased from the commercial power source and the electric power sold in reverse power to the commercial power source;
Obtaining power generation information from the power conditioner and buying and selling power information based on detection values of the current sensor, displaying a power consumption calculating unit for calculating power consumption from the generated power information and the buying and selling power information, and the power consumption A photovoltaic power generation display device including a power consumption display unit;
With
The power consumption is calculated from the sum of the generated power and the arithmetic average value of the purchased power per unit of the power conditioner, and the arithmetic average value of the power sold per unit of the power conditioner. It is calculated by the difference obtained by subtracting the,
The plurality of power conditioners are composed of a first power conditioner group composed of a plurality of the power conditioners and a second power conditioner group composed of a plurality of the power conditioners,
The power consumption displayed on the power consumption display unit is updated before the generated power of the first power conditioner group having the latest generated power at the time of display and the latest generated power at the time of display. The power purchase power and the power sale power obtained in synchronism with the sum of the generated power of the second power conditioner group having the generated power and the acquisition of the generated power information of each power conditioner And is calculated using
The power consumption displayed on the power consumption display unit is updated at regular intervals .

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