Output restricting method and system in photovoltaic power generation
Patent Information
- Application Number
- JP2023127983
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-08-04
- Publication Date
- 2025-02-17
Smart Images
Figure 2025023655000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a method and system for suppressing output in photovoltaic power generation. [Background technology]
[0002] To ensure a stable supply of electricity, it is necessary to balance the amount of power generated (supply) by solar power generation with the amount of power consumed. Conventionally, power transmission and distribution companies would send commands to the power generation companies that manage the solar power generation systems to suppress output by email, fax, etc. When the power generation company received a command to suppress output, it would create a schedule for the power generation system and operate the solar panels in order to control the solar power generation system in accordance with the command. [Prior art documents] [Non-patent literature]
[0003] [Non-Patent Document 1] Chubu Electric Power Grid Co., Ltd., “Connection of power generation facilities such as renewable energy, output control of power generation facilities”, [online], Chubu Electric Power Grid Co., Ltd., [Retrieved June 15, 2023], Internet<URL: https: / / powergrid.chuden.co.jp / goannai / ippan / powerconnection / facility / > [Non-Patent Document 2] Chubu Electric Power Grid Co., Ltd., “Technical Specifications for PCS with Output Control Function (Extra High Voltage) Established in July 2020, Revised in July 2023”, [online], Chubu Electric Power Grid Co., Ltd., [Retrieved June 30, 2023], Internet <URL: https: / / powergrid.chuden.co.jp / resource / goannai / ippan / powerconnection / facility / fcl_koukai / fcl_koukai_01.pdf> Summary of the Invention [Problem to be solved by the invention]
[0004] However, this work was done manually and was cumbersome. With the expected expansion of renewable energy power generation facilities, the power transmission and distribution companies are currently operating wide-area interconnections utilizing thermal power, pumped storage power generation, and regional interconnection lines. However, when the supply of electricity exceeds the demand, it is necessary to suppress the output of solar and wind power generation in order to maintain a stable supply of electricity. Since the amount of power generated by solar power generation fluctuates frequently depending on the weather, it is very difficult to maintain a balance between supply and demand. In addition, when the power output of a solar power plant reaches its maximum during the daytime when the demand for electricity is low, the supply will far exceed the demand if only the control of thermal power generation is used. Alternatively, the balance between supply and demand will be disrupted, causing frequency disturbances and causing large-scale blackouts. For these reasons, in order to maintain stable quality and supply of electricity, it is necessary to control the output of photovoltaic power generation, the amount of power generated of which can fluctuate frequently depending on the weather, and in recent years, rules for output control have been established through amendments to the ordinance of the Ministry of Economy, Trade and Industry (e.g., Non-Patent Document 1). In the future, photovoltaic power generation systems must be operated in compliance with the rules established by the amendments to the ordinance of the Ministry of Economy, Trade and Industry.
[0005] In view of the above problems, the present invention has an object to provide an output suppression method and system that can maintain stable quality and supply of power and can easily perform output suppression. [Means for solving the problem]
[0006] In order to solve the above problem, one aspect of the present invention is an output suppression method executed by a computer device, the method comprising the steps of: acquiring output control information for suppressing the amount of power generation of a solar power generation system; generating suppression schedule information for suppressing the amount of power generation of the solar power generation system based on the output control information; and transmitting control command information for controlling the amount of power generation of the solar power generation system in accordance with the suppression schedule information to at least a portion of a plurality of PCS monitoring devices that independently control each of a plurality of PCSs (Power Conditioning Systems).
[0007] Another aspect of the present invention is the above method, wherein the output control information includes at least output control time period information indicating a time period during which output suppression should be performed, and output upper limit information indicating an upper limit value for the amount of power generated by the solar power generation system during the time period during which output control should be performed.
[0008] Another aspect of the present invention is the above method, wherein the step of generating the suppression schedule information includes generating the suppression schedule for gradually reducing the output of at least a portion of the plurality of PCSs, and the control command information includes information indicating the time and the amount of output reduction for reducing the output of at least a portion of the plurality of PCSs based on the suppression schedule.
[0009] Another aspect of the present invention is the above-mentioned method, wherein the control command information is information for reducing outputs of at least a portion of the plurality of PCSs by 50% or 100%.
[0010] Another aspect of the present invention is the above method, wherein the step of generating the suppression schedule information includes determining whether to reduce the output of at least some of the multiple PCSs by 50% or 100% depending on the output value of each of the multiple PCSs and the maximum receiving power of the solar power generation system.
[0011] Another aspect of the present invention is the above method, wherein the step of transmitting the control command information includes transmitting, to at least some of the plurality of PCS monitoring devices, control command information for lifting the output suppression for at least some of the plurality of PCSs whose output has been suppressed. Another aspect of the present invention is a computer device for executing any of the above methods. Another aspect of the present invention is a computer program for causing a computer device to execute any of the above-described methods.
[0012] Another aspect of the present invention is an output suppression method executed by a first computer device that controls a power conditioner of a solar power generation system, the method including a step of receiving control command information for controlling the amount of power generation of the solar power generation system from an external second computer device, the control command information being information transmitted by the second computer device to the first computer device in order to obtain output control information for suppressing the amount of power generation of the solar power generation system, generate suppression schedule information for suppressing the amount of power generation of the solar power generation system based on the output control information, and control the first computer device in accordance with the suppression schedule information.
[0013] Another aspect of the invention is a first computer device for carrying out the above method. Another aspect of the present invention is a computer program for causing a first computer device to execute the above method. [Brief description of the drawings]
[0014] [Figure 1] FIG. 1 is a diagram showing an example of an overall configuration of an output suppression system according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a diagram illustrating an example of a functional block of the output suppression system according to the embodiment of the present invention. [Diagram 3] FIG. 2 is a diagram showing two control patterns for controlling a PCS. [Figure 4]11 is a diagram illustrating the overall output value after output suppression of each PCS. FIG. [Diagram 5] FIG. 13 is a diagram illustrating an example of a suppression schedule. [Figure 6] FIG. 13 is a diagram illustrating an example of a suppression schedule. [Figure 7] FIG. 11 is a flow chart showing an example of processing in a PLC. [Figure 8] FIG. 11 is a flow chart showing another example of processing in the PLC. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. (Overall configuration of output suppression system)
[0016] FIG. 1 is a diagram showing an example of the overall configuration of an output suppression system according to the present embodiment. The output suppression system 1 according to the present embodiment is configured to include a PLC (Programmable Logic Controller) 10, a computer device 20 of a power transmission and distribution company, a PCS (Power Conditioning System) monitoring device 30, and a PCS 35. The computer device 20 of the power transmission and distribution company monitors the balance between power demand and supply, and when it is determined that it is necessary to suppress the amount of power generation, transmits output control information, which is a command to suppress the power output, to the PLC 10 of the power generation company that manages the solar power generation system. The PLC 10, the PCS monitoring devices 30 (30-1, 30-2, . . . , 30-8), and the PCS 35 (35-1, 35-2, . . . , 35-8) constitute a part of the solar power generation system, and are devices managed by the power generation company that manages the solar power generation system. The PLC 10 is a computer device that controls the PCS monitoring device 30, and is a device that, when it receives output control information from the computer device 20, executes processing for suppressing the output of the PCS 35 based on the output control information. Moreover, the PCS 35 is a device that converts the generated power (DC) produced by a solar panel (not shown) into AC. Moreover, the PCS monitoring device 30 is a device that monitors the PCS 35. The PCS monitoring device 30 receives information on the operation / stop status of the PCS, the amount of generated power, the fault status, etc. in real time and transmits it to the PLC 10. Note that the PCS 35 is a generally well-known device. The PCS monitoring device 30 and the PLC 10 can be realized using a general-purpose PLC.
[0017] In this embodiment, a case will be described in which there are eight PCS monitoring devices 30 and eight PCSs 35, but this is merely an example, and the number of PCS monitoring devices 30 and eight PCSs 35 is not limited to this. In addition, the output control information transmitted from the computer device 20 of the electricity transmission and distribution company includes an output control signal indicating whether or not to perform output suppression, an output control time period signal indicating a time period during which output suppression should be performed, and an output upper limit value signal indicating an output upper limit value for the output control time period.
[0018] When the PLC 10 receives the output control information from the computer device 20, it generates a suppression schedule for output suppression. The suppression schedule is information indicating how the output of each PCS 35 should be controlled so as to satisfy the output suppression conditions indicated in the output control information. The PLC 10 transmits control command information to each PCS monitoring device 30 for controlling each PCS monitoring device 30 based on the generated suppression schedule. Each PCS monitoring device 30 controls and suppresses the output of the PCS 35 according to the control command information received from the PLC 10.
[0019] In this embodiment, as an example, it is assumed that the computer device 20 of the electricity transmission and distribution company performs output suppression control based on the technical specifications of the electricity transmission and distribution company of Non-Patent Document 2. (Function block of output suppression system)
[0020] Fig. 2 is a diagram showing an example of a functional block of the output suppression system according to the present embodiment. The output suppression system 1 according to the present embodiment may be configured to include a PLC 10, a computer device 20 of a power transmission and distribution company, a PCS monitoring device 30, and a PCS 35. Although only one PCS monitoring device 30 and one PCS 35 are shown in Fig. 2, there may be a plurality of PCS monitoring devices 30 and PCS 35 as shown in Fig. 1. In the present embodiment, the description will be given assuming that there are eight PCS monitoring devices 30 and eight PCS 35, but this is not limiting.
[0021] The computer device 20 of the electricity transmission and distribution company is a computer device operated by an operator of a power generation company that manages a solar power generation system. When the power generation company determines that the amount of power generated by the solar power generation system should be reduced based on the balance between supply and demand, the computer device 20 transmits output control information for reducing the amount of power generated by the solar power generation system to the PLC 10. The PLC 10, the PCS monitoring device 30, and the PCS 35 are devices managed by the power generation company that manages the solar power generation system. The computer device 20 and the PLC 10, and the PLC 10 and the PLC monitoring device 30 may be connected by a wired network. (Computer device 20)
[0022] The computer device 20 includes an output control information transmission unit 210. The output control information transmission unit 210 transmits the output control information to the PLC 10. The output control information includes at least output control time zone information indicating a time zone in which output suppression should be performed, and output upper limit information indicating an upper limit value of the amount of power generated by the photovoltaic power generation system in the time zone in which the output control should be performed. In this embodiment, the output control time zone information is an output control time zone signal defined in Non-Patent Document 2, and is a signal indicating the time zone (output control time zone) subject to output control in 30-minute units. In this embodiment, the output upper limit information is an output upper limit value signal defined in Non-Patent Document 2, and is indicated by a ratio (%) to the maximum receiving power. However, the output control time zone information and the output upper limit information in this embodiment are merely examples, and may be information in other formats. In addition, the output control information may further include other data. (PLC10) The PLC 10 includes an output control information acquisition unit 110, a power reduction schedule information generation unit 120, and a control command information transmission unit .
[0023] The output control information acquisition unit 110 acquires the output control information transmitted from the output control information transmission unit 210 of the computer device 20. As described above, the output control information may include a plurality of pieces of information, and each piece of information may be received at a different timing. In the present embodiment, the output control information acquisition unit 110 acquires the output control information by receiving the output control information transmitted from the computer device 20, but is not limited to this. For example, the output control information may be transmitted by the power generation company via email, facsimile, or the like, and the output control information may be input to the PLC 10 by an operator of the power generation company, or the like.
[0024] The suppression schedule information generating unit 120 generates suppression schedule information for suppressing the amount of power generation of the photovoltaic power generation system based on the output control information received by the output control information acquiring unit 110 .
[0025] The control command information transmitting unit 130 transmits control command information for controlling the power generation amount of the photovoltaic power generation system according to the suppression schedule information generated by the suppression schedule information generating unit 120 to at least some of the multiple PCS monitoring devices 30 that independently control each of the multiple PCSs 35. In addition, the control command information transmitting unit 130 transmits control command information for releasing the suppression of output for at least some of the multiple PCSs 35 whose output has been suppressed to at least some of the multiple PCS monitoring devices 30.
[0026] In addition, in this embodiment, the suppression schedule information generating unit 120 generates a suppression schedule for gradually reducing the output of at least a part of the multiple PCSs 35. At this time, the control command information includes information indicating the time and the reduced output amount at which the output of at least a part of the multiple PCSs is reduced based on the suppression schedule. The reduced output amount may be an amount of power or a ratio to the current output amount. In this embodiment, the control command information is information for reducing the output of at least a part of the multiple PCSs 35 by 50% or 100%. Furthermore, the suppression schedule information generating unit 120 may have a function of determining whether to reduce the output of at least a part of the multiple PCSs 35 by 50% or 100% according to the output value of each of the multiple PCSs 35 and the maximum receiving power of the photovoltaic power generation system. (PCS monitoring device 30)
[0027] The PCS monitoring device 30 includes a PCS control unit 310. The PCS control unit 310 receives control command information transmitted from the control command information transmission unit 130 of the PLC 10, and suppresses the output of the PCS 35 based on the control command information. Furthermore, each of the multiple PCS monitoring devices 30 can independently suppress the output of the PCS 35 to which it is connected. (Generate suppression schedule) An example of generation of a throttling schedule in the throttling schedule information generator 120 of the PLC 10 will be described below.
[0028] In the output control based on the technical specifications of the power transmission and distribution company in Non-Patent Document 2, a method of gradually reducing the output (power generation) of PCS35 at a certain step is permitted. Furthermore, when gradually reducing the output of PCS35, it is stipulated that each step should be suppressed to 10% or less of the maximum receiving power, taking into consideration the impact on the grid. In other words, for example, if the maximum receiving power is 8580 kW (kilowatts), the output of PCS35 must be reduced to 858 kW or less at each step. In the following explanation, as an example, the maximum receiving power of this embodiment will be explained as 8580 kW. (However, this is not limited to this.)
[0029] Furthermore, when the output of the PCS 35 is gradually reduced at regular steps, the time width of each step is set to a minimum of 30 seconds and a maximum of 1 minute in Non-Patent Document 2. That is, with the minimum time width, the total output of the PCS 35 is set to 0% in 5 minutes (reduced by 10% every 30 seconds), and with the maximum time width, the total output of the PCS 35 is set to 0% in 10 minutes (reduced by 10% every minute). In view of the above conditions, for example, controls such as the following "NG control 1" and "NG control 2" cannot be performed. (NG Control 1)
[0030] Stopping all eight PCSs 35 at once: This is because stopping all eight PCSs 35 at once would normally result in output suppression exceeding 10% of the maximum receiving power. This can be addressed by stopping the eight PCSs 35 in turn in each step (control method 1). This control method satisfies the above condition in the technical specifications of Non-Patent Document 2, which states that when the output of each PCS 35 is 858 kW or less (greater than 0 kW), the output is suppressed to 10% or less of the total capacity of the PCSs 35. (NG Control 2)
[0031] The above-mentioned "control method 1" is implemented when the output of each PCS35 is greater than 858 kW: this is because in this case, if the eight PCS35s are stopped in sequence, the output will be suppressed beyond 10% (858 kW) of the maximum receiving power. Therefore, in this embodiment, a method of suppressing the output of the PCS35 to 50% is used as a method of suppressing the output of the PCS35. That is, when the output of each PCS35 is greater than 858 kW, the output of each PCS35 is suppressed from 100% to 50% in one step, and then further suppressed from 50% to 0% in the next step (hereinafter, such control may be referred to as "50% control"). The output of the eight PCS35s is stopped in sequence by such control (control method 2).
[0032] Fig. 3 is a diagram showing two control patterns for controlling the PCS 35 of this embodiment. In this embodiment, the control patterns can be classified into two types (control patterns 1 and 2) as shown in Fig. 3 depending on whether or not a function for suppressing the output of each PCS 35 to 50% is used. Each control pattern will be described below with examples. (Control pattern 1)
[0033] Control pattern 1 will be described below. In this description, as an example, it is assumed that the output of each PCS 35 at the time when output suppression is to be started is 1000 kW, and the total output of the eight PCSs 35 is 8000 kW. As described above, the maximum receiving power is 8580 kW. Note that the eight PCSs 35 are devices that convert the output from the solar panels that generate solar power in environments that can be considered almost identical, into AC, so the outputs of the eight PCSs 35 can all be considered to be the same (this is true throughout this specification).
[0034] In this example, since the output of each PCS35 is 1000kW, according to FIG. 3, the function of suppressing by 50% must be used. That is, the output of the eight PCS35s is reduced in sequence by 50%, i.e., by 500kW. In the following explanation, the eight PCS35s will be referred to as "PCS8", "PCS7", ... "PCS1". First, the output of the first PCS8 is reduced by 50% (500kW) in the first 30 seconds, and then reduced by another 50% (500kW) in the next 30 seconds. As a result, the output of PCS8 is reduced from 100% to 0% in one minute. Next, the output of PCS7 is similarly reduced by 50% (500kW) every 30 seconds, and is reduced from 100% to 0% in one minute. This is repeated in sequence for PCS6, PCS5, ..., until the output of all PCSs is 0kW after eight minutes. In this control pattern, each step is 30 seconds wide, and the overall output of the PCS 35 is reduced by 500 kW / 8580 kW (maximum receiving power) = about 5.8% for each step. In other words, according to the control pattern 1, the conditions set forth in Non-Patent Document 2 can be satisfied.
[0035] As described above, the output control information output from the computer device 20 includes output upper limit information indicating the upper limit of the amount of power generated by the photovoltaic power generation system during the time period when output control should be performed. In this embodiment, the output upper limit information is indicated as a percentage (%) of the maximum receiving power. Here, FIG. 4 is a diagram showing what the overall output value of the (8) PCSs 35 will be each time the output of each PCS 35 becomes 0%, and what percentage this overall output value is relative to the maximum receiving power. The values of "overall output value" and "% relative to maximum receiving power" in FIG. 4 can be calculated as follows. Total output value = current total output value of all PCS - 1000 (current output value of each PCS) x number of PCS whose output has reached 0% % of maximum receiving power = total output value ÷ maximum receiving power × 100
[0036] For example, when the outputs of PCS8 and PCS7 become 0%, the total output value becomes 6000kW, which is about 69.93% of the maximum receiving power. For example, when the output upper limit information included in the output control information output from the computer device 20 indicates a value of "50%," according to Fig. 4, when the output of PCS5 becomes 0%, the ratio of the total output value to the maximum receiving power becomes 46.62%. In other words, by lowering the output values to 0% in order from PCS8 to PCS5, the value of the output upper limit information is satisfied, and there is no need to perform suppression control for PCS4 and onward.
[0037] At this time, the control command information transmitted from the control command information transmitting unit 130 of the PLC 10 has the following contents. That is, the control command information from the PCS 8 to the PCS 5 (control command information from the PCS monitoring device 8 to the PCS monitoring device 5) is information to reduce the output from 100% to 50% and further reduce the output from 50% to 0%, and the control command information may not be transmitted from the PCS 4 to the PCS 0, or information to the effect that output suppression will not be performed may be transmitted as the control command information. Note that, if the output value of the entire PCS 35 satisfies the upper limit value indicated by the output upper limit information by reducing the output of a certain PCS from 100% to 50%, the control to reduce the output of the PCS from 50% to 0% thereafter may not be executed (this also applies to control pattern 2 described later).
[0038] More specifically, for example, it is assumed that the output control information acquisition unit 110 of the PLSPLC 10 receives output control information from the computer device 20, in which the output control time period information is "9:00-12:30" and the output upper limit information is "50%". Then, the suppression schedule information generation unit 120 judges whether to adopt control pattern 1 or control pattern 2 (or whether to use 50% control) according to the current overall output value of the eight PCSs 35. If it is judged that control pattern 1 should be adopted, a suppression schedule is generated in which the output of each PCS is reduced from 100% to 50% in the first 30 seconds (referred to as "suppression control 1"), starting from PCS8, and then further reduced from 50% to 0% in the next 30 seconds (referred to as "suppression control 2"). In addition, since the output upper limit information indicates "50%, the suppression schedule information generation unit 120 judges that suppression control 1 and suppression control 2 should be performed in the order from PCS8 to PCS5. The control command information transmitting unit 130 transmits control command information to the PCS monitoring device controlling the PCS8 to reduce the output of the PCS8 from 100% to 50% at time 9:00:00 according to the suppression schedule. Furthermore, at time 9:00:30, it transmits control command information to the PCS monitoring device controlling the PCS8 to reduce the output of the PCS8 from 50% to 0%. The PCS control unit 310 of the PCS monitoring device 30 that received each control command information suppresses the output of the PCS8 by 50% according to the control command information transmitted at time 9:00:00 and time 9:00:30. Similarly, for PCS7 and onwards, control command information is transmitted to each PCS monitoring device 30 to execute suppression control 1 and suppression control 2 every 30 seconds, and in response, each PCS monitoring device suppresses the output of each PCS by 50%. For PCS4 and onwards that do not execute output suppression, control command information may not be transmitted, or control command information to the effect that suppression control is not executed may be transmitted.The control command information transmitting unit 130 may be configured to sequentially transmit control command information indicating the output amount to be suppressed at the timing to perform output suppression (which may be shown in various formats such as absolute value, ratio to current output value, etc.) as in this example, or may be configured to transmit control command information including the timing to perform output suppression (which may be shown in various formats such as time, minutes from now, etc.) and the output amount to be suppressed at each timing before starting output suppression (the same applies below).
[0039] FIG. 5 is an example of a suppression schedule, and is a diagram showing the timing of transmitting control command information when suppression control of control pattern 1 is performed. "Control command information transmission (suppression control 1)" and "control command information transmission (suppression control 2)" in FIG. 5 indicate the timing at which control command information for executing suppression control 1 and 2 is transmitted to each PCS ("No." in FIG. 5 indicates the number of each PCS). Also, "device status (suppression control 1)" and "device status (suppression control 2)" indicate the timing at which the output of each PCS changes due to the control command information. That is, in this example, when the control command information is transmitted from the control command information transmitting unit 130, the output of each PCS changes with almost no delay. However, this example is merely an example, and depending on the performance of the PCS, the communication method, etc., there may be a delay between when the control command information is transmitted and when the output of each PCS changes. In this case, in consideration of the delay, the transmission of the control command information may be started earlier by the delay time than the control start time specified by the output control time period information of the output control information (the same applies to the example described below).
[0040] The same applies when releasing the output suppression state. Since the time of suppression control end indicated by the output control time zone information is 12:30, the control command information transmitting unit 130 sequentially transmits control command information for releasing the suppression of the output of PCS8 to PCS5 whose output has been suppressed, from 12:30 to each PCS monitoring device 30 that manages PCS8 to PCS5. Also, in this case, if a delay occurs between the transmission of the control command information and the recovery of the output of each PCS, the control command information may be transmitted earlier than the suppression release time (12:30) by the delay time, taking into account the delay. (Control pattern 2)
[0041] Control pattern 2 will be described below. In this description, it is assumed, as an example, that the output of each PCS 35 is 800 kW and the total output of the eight PCSs 35 is 6400 kW. Control pattern 2 is further divided into two patterns. One is a pattern that uses output suppression in 50% increments, and the other is a pattern that does not use output suppression in 50% increments. Below, control pattern 2-1 that uses output suppression in 50% increments and control pattern 2-2 that does not use output suppression in 50% increments will be described. (Control pattern 2-1)
[0042] First, control pattern 2-1 will be described. In this example, the output of each PCS 35 is reduced in sequence by 50%, that is, by 400 kW. In this example, as in the example of control pattern 1 described above, the output of each PCS is reduced by 50% (400 kW) in the first 30 seconds in the order of PCS8, PCS7, ..., PCS1, and then reduced by another 50% (400 kW) in the next 30 seconds. Finally, after 8 minutes, the output of all PCSs becomes 0 kW. In this control pattern, each step is 30 seconds wide, and the overall output of the PCS 35 is reduced by 400 kW / 8580 kW (maximum receiving power) = about 4.7% in each step. That is, according to control pattern 2-1, the conditions set forth in Non-Patent Document 2 can be satisfied. This control pattern can be realized in the same way as control pattern 1 described above. (Control pattern 2-2)
[0043] Next, control pattern 2-2 will be described. In this example, the output of each PCS 35 is sequentially reduced by 100%, that is, by 800 kW. In this example, the output of each PCS is reduced by 100% (800 kW) in 30 seconds to 1 minute in the order of PCS8, PCS7, ..., PCS1. Finally, after 8 minutes, the output of all PCSs becomes 0 kW. In this control pattern, each step is 1 minute wide, and the overall output of PCS 35 is reduced by 800 kW / 8580 kW (maximum receiving power) x 100 = about 9.3% for each step. In other words, the conditions defined in Non-Patent Document 2 can be satisfied by control pattern 2-2 as well. In addition, whether to perform 50% control (control pattern 1 and control pattern 2-1) or not to perform 50% control (control pattern 2-2) may be determined, for example, so that 50% control is performed when the total output of PCS35 at the start of suppression control is more than half of the maximum receiving power, and that 50% control is not performed when the total output of PCS35 at the start of suppression control is less than half of the maximum receiving power.
[0044] Fig. 6 is an example of a suppression schedule, similar to Fig. 5, and shows the timing of transmitting control command information when suppression control of control pattern 2-2 is performed. "Control command information transmission" in Fig. 6 shows the timing of transmitting control command information to each PCS to suppress the output of each PCS from 100% to 0%. Also, "device status" shows the timing of changing the output of each PCS due to the control command information. Other points are the same as Fig. 5.
[0045] As described above, the control methods such as control pattern 1, control pattern 2-1, and control pattern 2-2 can suppress the power generation amount of the photovoltaic power generation system while satisfying the conditions defined in Non-Patent Document 2. The conditions in Fig. 3 can be generalized as follows. When the output X of each PCS satisfies the condition: maximum power reception kW × 10% < X kW, each PCS is stopped in sequence using 50% control (control pattern 1). When the output X of each PCS satisfies the condition: 0 kW < X kW ≤ maximum power reception kW × 10%, each PCS is stopped in sequence using 50% control or without using 50% control (control pattern 2).
[0046] Also, when output control information is transmitted from the computer 20 of the power transmission and distribution utility to the PLC 10, the following method can be used to determine whether to perform 50% control in the PLC 10. (1) Determine based on the solar irradiance. Predict the output of each PCS 35 using a pyranometer. When the sum of the predicted output values of each PCS 35 is equal to or more than half of the maximum power reception, perform 50% control. When the sum is less than half of the maximum power reception, determine not to perform 50% control. (2) Determine based on the season and time. For example, from April to September, from 6:00 to 18:00, it is assumed that the power generation is large, so perform 50% control. From January to March and from October to December, from 8:00 to 16:00, it is assumed that the power generation is small, so determine not to perform 50% control. (Flow chart)
[0047] FIG. 7 is a flow chart showing an example of the processing in the PLC 10 of the present embodiment. The flow chart of FIG. 7 corresponds to the case of performing 50% control (control patterns 1 and 2-1).
[0048] In step S110, the output control information acquisition unit 110 acquires output control information. The output control information includes output control time zone information and output upper limit information. In step S120, the suppression schedule information generation unit 120 generates a suppression schedule using the output control time zone information and the output upper limit information of the output control information received in step S110. In step S130, the number k of the PCS 35 (PCS monitoring device 30) to suppress the output is set to "8".
[0049] In step S140, control command information is transmitted to the number k PCS monitoring device 30. The control command information transmitted here is for reducing the output of the number k PCS monitoring device 30 from 100% to 50%.
[0050] After 30 seconds have elapsed (step S150), in step S160, control command information is transmitted to the PCS monitoring device 30 numbered k. The control command information transmitted here is for reducing the output of the PCS monitoring device 30 numbered k from 50% to 0%. After 30 seconds have elapsed (step S170), k is set to k-1 in step S180. Furthermore, the process from step S140 is repeated until output suppression becomes unnecessary (for example, until k=4) (step S190).
[0051] Fig. 8 is a flow diagram showing another example of processing in the PLC 10 of this embodiment. The flow diagram in Fig. 8 corresponds to a case where 50% control is not performed (control pattern 2-2; a case where the output value of each PCS 35 is controlled from 100% to 0%). Note that in Fig. 8, steps with the same reference numerals as in Fig. 7 are the same as in Fig. 7. That is, steps S110 to S130 are the same as in Fig. 7.
[0052] In step S210, control command information is transmitted to the k-th PCS monitoring device 30. The control command information transmitted here is for suppressing the output of the k-th PCS monitoring device 30 from 100% to 0%. After one minute has elapsed (step S220), k is set to k-1 in step S180.
[0053] The process flow showing an example of the process in PLC 10 shown in Fig. 7 and Fig. 8, and the process executed by PCS monitoring device 30 can be realized as a general-purpose PLC program by a generally well-known method. In the present embodiment, PLC 10 is assumed to be a general-purpose PLC, but it can be realized by a hardware configuration similar to that of a general computer device. The PCS monitoring device 30 can also be realized by a hardware configuration similar to that of a general computer device. That is, for example, a computer device equipped with a processor (electronic circuits such as a CPU (Central Processing Unit) or a microprocessor), a RAM (Random Access Memory), a ROM (Read Only Memory), an internal hard disk drive, an external hard disk drive, a removable memory such as a CD, a DVD, a USB memory, a memory stick, an SD card, an input / output user interface (keyboard, mouse, touch panel, speaker, microphone, LED (light emitting diode), etc.) for a user to input and output data to and from the computer device, a wired / wireless communication interface capable of communicating with other computer devices, and a display, etc., in which the processor reads a program stored in a storage area such as a hard disk drive, ROM, or removable memory into a memory area such as RAM, and executes the program while appropriately reading data necessary for processing from the storage area such as a hard disk drive, ROM, or removable memory, thereby realizing the processing of FIG. 7 or FIG. 8 and the processing executed by the PCS monitoring device 30.
[0054] In addition, the computer program that realizes the processing of Figure 7 or Figure 8 and the processing executed by the PCS monitoring device 30 can be stored in part or in whole on a computer-readable recording medium or downloaded via a wired or wireless communication network.
[0055] According to the output suppression method and output suppression system of the present embodiment described above, a suppression schedule can be automatically generated in response to a request for output suppression from a power transmission and distribution company, and the output of a plurality of PCSs 35 can be suppressed. Conventionally, the power transmission and distribution company notifies the power generation company of output suppression by email, facsimile, or the like, and the power generation company creates a schedule for the power generation system and operates the solar panels in order to control the solar power generation system according to the notification. However, when output control information is transmitted from the computer device 20 of the power transmission and distribution company by data communication, the conventional complicated work is no longer necessary.
[0056] Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above-described embodiment and may be embodied in various different forms within the scope of the technical concept thereof.
[0057] Moreover, the scope of the present invention is not limited to the exemplary embodiments shown and described, but includes all embodiments that achieve the same effect as the object of the present invention. Furthermore, the scope of the present invention is not limited to the combination of the features of the invention defined by each claim, but may be defined by any desired combination of specific features among all the respective features disclosed. The following embodiments are also within the scope of the present invention.
[0058] (Invention 1) 1. A method of curtailment implemented by a computer device, comprising: Obtaining output control information for suppressing the amount of power generated by the photovoltaic power generation system; generating suppression schedule information for suppressing the amount of power generation of the photovoltaic power generation system based on the output control information; transmitting control command information for controlling the amount of power generated by the photovoltaic power generation system in accordance with the suppression schedule information to at least a part of a plurality of PCS monitoring devices that independently control each of a plurality of PCSs (Power Conditioning Systems); A method for providing the above. (Invention 2) The method described in (Invention 1), wherein the output control information includes at least output control time period information indicating a time period during which output suppression should be performed, and output upper limit information indicating an upper limit value of the power generation amount of the solar power generation system during the time period during which the output control should be performed. (Invention 3) the step of generating throttling schedule information includes generating the throttling schedule for gradually reducing outputs of at least a portion of the plurality of PCSs; The method according to (Invention 1) or (Invention 2), wherein the control command information includes information indicating the time and the amount of output reduction at which the output of at least a portion of the plurality of PCSs is reduced based on the suppression schedule. (Invention 4) The method according to (Invention 3), wherein the control command information is information for reducing the output of at least a portion of the plurality of PCSs by 50% or 100%. (Invention 5) The method described in (Invention 4), wherein the step of generating suppression schedule information includes determining whether to reduce the output of at least some of the multiple PCSs by 50% or 100% depending on the output value of each of the multiple PCSs and the maximum receiving power of the solar power generation system. (Invention 6) A method according to any one of (Invention 1) to (Invention 5), wherein the step of transmitting control command information includes transmitting control command information for releasing the output suppression for at least some of the plurality of PCSs whose output has been suppressed to at least some of the plurality of PCS monitoring devices. (Invention 7) A computer device for carrying out the method according to any one of (Invention 1) to (Invention 6). (Invention 8) A computer program for causing a computer device to execute the method according to any one of (Invention 1) to (Invention 6). (Invention 9) An output suppression method executed by a first computer device that controls a power conditioner of a solar power generation system, receiving control command information for controlling the amount of power generation of the solar power generation system from an external second computer device; A method in which the control command information is information transmitted by the second computer device to the first computer device in order to obtain output control information for suppressing the amount of power generation of the solar power generation system, generate suppression schedule information for suppressing the amount of power generation of the solar power generation system based on the output control information, and control the first computer device in accordance with the suppression schedule information. (Invention 10) A computer apparatus for carrying out the method according to (Invention 9). (Invention 11) A computer program for causing a computer device to execute the method according to (Invention 9). [Explanation of symbols]
[0059] 1. Output suppression system 10...PLC 110...Output control information acquisition unit 120... Suppression schedule information generation unit 130...Control command information transmission unit 20...Computer equipment 210...output control information transmission unit 30...PCS monitoring device 310...PCS control unit 35…PCS
Claims
1. 1. A method of curtailment implemented by a computer device, comprising: Obtaining output control information for suppressing the amount of power generated by the photovoltaic power generation system; generating suppression schedule information for suppressing the amount of power generation of the photovoltaic power generation system based on the output control information; transmitting control command information for controlling the amount of power generated by the photovoltaic power generation system in accordance with the suppression schedule information to at least a part of a plurality of PCS monitoring devices that independently control each of a plurality of PCSs (Power Conditioning Systems); A method for providing the above.
2. The method according to claim 1, wherein the output control information includes at least output control time period information indicating a time period during which output suppression should be performed, and output upper limit information indicating an upper limit value of the power generation amount of the solar power generation system during the time period during which the output control should be performed.
3. the step of generating throttling schedule information includes generating the throttling schedule for gradually reducing output of at least a portion of the plurality of PCSs; The method of claim 1 , wherein the control command information includes information indicating a time and an amount of output reduction to reduce the output of at least a portion of the plurality of PCSs based on the suppression schedule.
4. The method according to claim 3 , wherein the control command information is information for reducing the output of at least a portion of the plurality of PCSs by a rate of 50% or 100%.
5. The method of claim 4, wherein the step of generating the suppression schedule information includes determining whether to reduce the output of at least some of the multiple PCSs by 50% or 100% depending on the output values of each of the multiple PCSs and the maximum receiving power of the solar power generation system.
6. 2. The method of claim 1, wherein the step of transmitting control command information includes transmitting control command information for releasing the output suppression for at least some of the plurality of PCSs whose output has been suppressed to at least some of the plurality of PCS monitoring devices.
7. Computer apparatus for carrying out the method according to any one of claims 1 to 6.
8. A computer program product for causing a computer device to carry out the method according to any one of claims 1 to 6.
9. An output suppression method executed by a first computer device that controls a power conditioner of a solar power generation system, receiving control command information for controlling a power generation amount of the solar power generation system from an external second computer device; A method in which the control command information is information transmitted by the second computer device to the first computer device in order to acquire output control information for suppressing the amount of power generation of the solar power generation system, generate suppression schedule information for suppressing the amount of power generation of the solar power generation system based on the output control information, and control the first computer device in accordance with the suppression schedule information.
10. A computer apparatus for carrying out the method of claim 9.
11. A computer program product for causing a computer device to carry out the method according to claim 9.