JP6545367B2 - Power generation system - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a power generation system capable of reverse power flow to a grid with a power conditioner.

  In addition to the recent rise in environmental awareness, solar power generation equipment is installed on the roof of a house etc. for the purpose of measures against rising power rates, and the solar power generated by the solar power generation equipment is consumed by the load at home Introduction of battery power generation system is in progress.

  Then, among the amount of electric power generated by the solar power generation device, the amount of electric power exceeding the amount consumed by the home is reversely flowed to the grid of the electric power company to sell the excess electric power, thereby reducing the electricity charge There is also a power generation system. Furthermore, there is also a solar power generation system that benefits from selling the entire amount of power generated by the solar power generation device.

  In order to keep the power supply of the grid stable, according to the instructions from the power company based on the receiving situation in each power company tube, the photovoltaic power generation system controls the amount of power flowing back by stopping or suppressing the reverse power flow There is a need.

  As a means of controlling the amount of power that the photovoltaic power generation system reversely flows, a method of controlling the amount of power that can be reversed can be used by measuring the amount of power received and supplied to the grid.

  In a solar power generation system in which reverse power flow is considered impossible, it is necessary to stop the solar power generation device if reverse power flow is likely to occur. When the solar power generation device is stopped, the amount of power from the solar power generation device can not be used for home consumption, and the solar power generation system can not be used effectively because the power company must receive power.

  In order to avoid this, the amount of power received from the grid is measured, and the threshold of the amount of received power set to forcibly stop the solar power generation system is varied according to the amount of power to stop the solar power generation system. A means for avoiding and effectively utilizing it is known (see, for example, Patent Document 1).

JP 2012-175858 A

  In order to safely reverse the amount of power generated by the solar power generation device to the grid of the power company, it is necessary to correctly measure the amount of reversely transferred power. A CT (CURRENT TRANSFORMER) sensor is used as a means to correctly measure the amount of power flowing backward.

  Although the CT sensor needs to be installed correctly on the electric path from inside the house to the grid, if the CT sensor is installed incorrectly, the amount of power flowing backward can not be measured correctly, It is not possible to control the amount of reversely flowing power correctly.

  The inability to properly control the amount of reversely flowing power causes unfairness in that the amount of reversely flowing power differs among the users who possess the solar power generation device. Furthermore, the reverse flow of the amount of power exceeding the allowable power of the electric power company makes it difficult to maintain the whole electric power network of the electric power company normally, which may cause a failure leading to a power failure. In addition, even if the power failure does not occur, the power transmission equipment of the power company may be damaged.

  The present invention has been made in view of the above, and it is an object of the present invention to obtain a power generation system capable of detecting a defect in attachment of a CT sensor with a simple mechanism.

  In order to solve the problems described above and achieve the object, the present invention provides a power conditioner for supplying generated power generated by a power generation device to a grid power supply, and reverse flow power from the power conditioner to the grid power supply. And a reverse flow measurement unit which is measurement means for determining a reverse flow power amount which is a quantity. The power conditioner has a control unit that determines that the installation method of the reverse flow measurement unit is incorrect when the average value of the reverse flow power amount during a fixed period or the integrated power amount is less than or equal to a preset threshold. It is characterized by

  According to the present invention, it is possible to detect a defect in attachment of a CT sensor with a simple mechanism.

Configuration diagram of a power generation system according to Embodiment 1 of the present invention FIG. 6 is a diagram showing an example of one-day transition of the power consumption Y consumed by the home load according to the first embodiment. The figure which shows the example of transition of the amount of electric power generation X by the solar power generation device concerning Embodiment 1 on the 1st The figure which shows the relationship of transition of the amount of electric power generation X by the solar power generation device concerning Embodiment 1 and the amount of electric power consumption Y consumed by home load one day A flowchart showing a processing procedure executed by the control circuit according to the first embodiment to detect improper installation of a CT sensor The figure which shows the example of the amount of reverse flow electric power in case the amount X of generated energy of the solar power generation device concerning Embodiment 1 is large The figure which shows the example of the reverse flow electric power amount in case the electric power generation amount X of the solar power generation device concerning Embodiment 1 is small. Another flowchart showing a processing procedure executed by the control circuit according to the first embodiment to detect improper installation of a CT sensor Block diagram showing the configuration of the microcomputer according to the first embodiment

  Hereinafter, a power generation system according to an embodiment of the present invention will be described in detail based on the drawings. The present invention is not limited by the embodiment.

Embodiment 1
FIG. 1 is a block diagram of a power generation system 100 according to a first embodiment of the present invention. The power generation system 100 includes a photovoltaic power generation device 1 that is a power generation device, a power conditioner 2, a home load 3 such as an electrical product in the home, a grid 4 that is a grid power supply of a power company, a remote controller 9, a CT sensor 10 is a grid-connected photovoltaic power generation system. The solar power generation device 1 is connected to the power conditioner 2, and is connected to the home load 3 or the grid 4 of the electric power company via the power conditioner 2.

  The power conditioner 2 includes an inverter circuit 5, a control circuit 6 which is a control unit, a protection circuit device 7, a communication circuit 8, a generated power measuring device 20, and a display unit 21. The communication circuit 8 may be provided separately from the power conditioner 2. Furthermore, a connection device such as a remote controller 9 is connected to the display information output terminal 102 of the power conditioner 2. The remote controller 9 includes a display unit 91, and is used for setting of the operation mode by the user and monitoring of the operation state by the user.

  The inverter circuit 5 converts the DC power generated by the solar power generation device 1 into AC power. The protection circuit device 7 shuts off the output of the power conditioner 2 when any abnormality occurs in the power conditioner 2 and protects the home load 3 or the system 4 from a failure. The communication circuit 8 receives an output control instruction for the amount of power that can be transferred back to the grid 4 from the power company in each region. The power generation amount measuring device 20 measures a generated power amount X which is a power amount of DC generated power input from the solar power generation device 1 to the power conditioner 2.

  The control circuit 6 controls the received voltage from the solar power generation device 1 based on the information measured by the power generation amount measurement device 20 so that the power generation amount of the solar power generation device 1 can be extracted stably and at a maximum amount. At the same time, the control circuit 6 controls the inverter circuit 5 and the protection circuit device 7 to supply power to the home load 3. Then, when the amount of power supplied from the solar power generation device 1 becomes surplus, the amount of power that the control circuit 6 reversely flows to the grid 4 based on the output control instruction from the power company received by the communication circuit 8 Control.

  When the amount of power generated by the solar power generation device 1 is less than the amount of power consumed by the home load 3, AC power is received from the grid 4, that is, power is purchased and used by the home load 3. When the amount of power generated by the solar power generation device 1 exceeds the amount of power consumed by the home load 3, the excess amount of power is reversely flowed to the grid 4, that is, sold. In order to reverse power flow, it is necessary to contract with a local power company in advance. Control of execution of purchase and sale of electricity is executed by the power conditioner 2.

  When the supply of AC power from the grid 4 is stopped due to some cause such as a power failure, the power generation system 100 performs independent operation covering the home load 3 only with the power generated by the photovoltaic power generation device 1 independently from the grid 4 Is also possible.

  In the power generation system 100, a CT sensor 10 is installed in an electric path connecting the grid 4 and the in-home load 3 in order to measure the amount of power flowing backward to the grid 4. The CT sensor 10 outputs a small current converted by the number of turns wound on the iron core against the current flowing in the electric path passing through the inside of the ring-shaped iron core inside the sensor. When the control circuit 6 measures the current output from the CT sensor 10, it is possible to obtain a reverse flow power amount which is a power amount flowing back to the grid 4 through the electric path. That is, the CT sensor 10 functions as a reverse power flow measurement unit which is measurement means for obtaining the reverse flow power amount. An analog current output signal indicating a current value flowing in the electric path measured by the CT sensor 10 is output from the CT sensor 10 and input to the reverse flow input terminal 101 of the power conditioner 2. The control circuit 6 determines the amount of reverse flow power based on the current value received from the CT sensor 10.

  FIG. 2 is a diagram showing an example of the transition of the power consumption amount Y consumed by the indoor load 3 according to the first embodiment. The vertical axis shows the amount of power, and the horizontal axis shows time. The amount of power consumption Y consumed by the home load 3 varies depending on the season, time, increase and decrease of electrical products used, and also varies depending on the climate or region.

  When installing the solar power generation device 1, the maximum amount of power that can be generated is determined by the number of the solar power generation devices 1, the azimuth or angle to be installed, and the like. The amount of generated power X generated by the solar power generation device 1 fluctuates depending on the amount of sunshine received, and therefore also fluctuates depending on the season, time, weather, and the like. FIG. 3 is a diagram showing an example of the transition of one day of the amount X of power generation by the solar power generation device 1 according to the first embodiment. The vertical axis shows the amount of power, and the horizontal axis shows time. In FIG. 3, the amount of generated power X when the solar power generation device 1 is installed in the east direction is indicated by a broken line, and the amount of generated energy X when the solar power generation device 1 is installed in the south direction is illustrated by a solid line The electric power generation amount X in case the solar power generation device 1 is installed in the west direction is shown with a dashed-dotted line.

  It is possible to estimate in advance whether reverse power flow occurs or not from the maximum value of the generated power amount X and the consumed power amount Y consumed by the home load 3. FIG. 4 is a view showing the relationship between the transition of one day of the amount of power generation X by the solar power generation apparatus 1 according to the first embodiment and the amount of power consumption Y consumed by the home load 3. The vertical axis shows the amount of power, and the horizontal axis shows time. In FIG. 4, during a given time during which daytime solar power generation is possible, the amount of generated power X> the amount of consumed power Y, and a reverse power flow occurs.

  The detection of the installation defect of the CT sensor 10 needs to be performed in the time zone in which the reverse power flow occurs and the reverse flow power is generated. FIG. 5 is a flowchart showing a processing procedure executed by the control circuit 6 according to the first embodiment to detect a mounting defect of the CT sensor 10.

  First, the CT sensor 10 constantly measures the reverse flow current which is the current of the electric path due to the reverse flow (step S101). Then, the control circuit 6 receives the current value signal output from the CT sensor 10, calculates reverse flow power amount based on the value of the current value signal (step S102), and constantly monitors the reverse flow power amount. There is. The reverse flow power amount is (generated power amount X-power consumption amount Y).

  The control circuit 6 performs the determination that the installation method of the CT sensor 10 is incorrect, that is, the determination of the installation defect, in the time zone in which the generated power amount X of the solar power generation device 1 is the maximum power generation amount. That is, the control circuit 6 determines whether or not the power generation amount X of the solar power generation device 1 is a time zone in which the maximum power generation amount is to be obtained (step S103). When the installation direction of the solar power generation device 1 is south, the user sets the time period when the power generation amount X of the solar power generation device 1 is the maximum power generation, around the noon. However, as can be seen from FIG. 3, when the time zone in which the maximum power generation amount is obtained is different from the above depending on the installation direction of the solar power generation device 1, the generated power amount X is the maximum power generation amount using a means such as the remote controller 9 Allow the user to change the time zone.

  When the power generation amount X of the solar power generation device 1 is not a time zone in which the maximum power generation amount is obtained (step S103: No), the process returns to step S103. When the power generation amount X of the solar power generation device 1 is a time zone in which the maximum power generation amount is obtained (step S103: Yes), the control circuit 6 determines whether reverse power flow is generated (step S104). In step S104, the control circuit 6 determines that reverse power flow occurs when the generated power amount X> power consumption amount Y, that is, the reverse flow power amount obtained in step S102 is larger than zero. If the control circuit 6 determines that no reverse power flow has occurred (step S104: No), it is not determined that the CT sensor 10 is improperly mounted (step S109).

  In step S104, when the control circuit 6 determines that reverse power flow is occurring (step S104: Yes), the control circuit 6 determines whether or not the generated power amount X measured by the generated power amount measuring device 20 is small. (Step S105). If the weather is bad, the amount of power generation X will be small. The control circuit 6 executes the determination of step S105 by comparing the generated power amount X with a predetermined generated power amount threshold. When the control circuit 6 determines that the weather is bad and the generated power amount X is small (step S105: Yes), the control circuit 6 does not determine the mounting defect of the CT sensor 10 (step S109). When the control circuit 6 determines that the generated energy amount X is not small (step S105: No), the control circuit 6 determines whether the reverse flow power amount is larger than a preset threshold value α (step S106).

  When the control circuit 6 determines that the reverse flow power amount is larger than the threshold value α, that is, (generated power amount X-power consumption amount Y)> α (step S106: Yes), the control circuit 6 It is determined that the attachment is normal (step S107).

  On the other hand, when the control circuit 6 determines that the reverse flow power amount is equal to or less than the threshold value α, that is, (generated power amount X-power consumption amount Y) ≦ α (step S106: No), the reverse flow power amount is Although it is a time zone that should be large enough and the amount of generated energy X is normal, the amount of reverse flow power is smaller than the threshold value α, which is a sufficiently small value, and the installation of the CT sensor 10 is abnormal It is believed that there is. Therefore, in this case, the control circuit 6 determines that there is a defect in the attachment of the CT sensor 10 (step S108).

  In the control circuit 6, a threshold value α used in step S106 is set as a value to prevent an erroneous determination due to a short time fluctuation of the generated power amount X and the power consumption amount Y. FIG. 6 is a diagram showing an example of the amount of reverse flow power when the power generation amount X of the solar power generation device 1 according to the first embodiment is large. The vertical axis shows the amount of power, and the horizontal axis shows time. As shown in FIG. 6, the control circuit 6 stably detects the mounting defect of the CT sensor 10 by setting the threshold value α to a small value with sufficient margin from the maximum power amount of the reverse flow power amount XY become able to. The installer of the power generation system 100 can set the threshold value α by the remote controller 9, and the threshold value α is protected using a password or the like. That is, only the installer can change the threshold α, and the user can arbitrarily change the threshold α.

  Since the amount of power generation X of the solar power generation device 1 and the amount of power consumption Y consumed by the home load 3 change every moment, the determination of the installation defect of the CT sensor 10 in step S106 is the moment of detection by the CT sensor 10 Instead of the backward flow power amount, the reverse flow power amount averaged over a predetermined fixed period, for example, about 0.5 to 1.0 hours, is used. Alternatively, determination is made using the integrated power amount of the backward flow power amount in the period. The threshold used when making determination using the integrated power amount uses the value of the product of the threshold value α and the integration time.

  A specific example of the threshold value α is shown below. When the power generation amount X by the solar power generation device 1 is 5.0 kW and the power consumption Y consumed by the home load 3 is 2.5 kW, the reverse flow power amount XY is 5.0 kW-2.5 kW = 2.5 kW. If the threshold value α for determining whether or not the attachment of the CT sensor 10 is normal is set to 2.0 kW, then (X−Y)> α is satisfied (step S106: Yes), and the control circuit 6 selects the CT sensor It is determined that the attachment of 10 is normal (step S107).

  When the weather is good and the amount of sunshine is large, the maximum power generation amount of the power generation amount X by the solar power generation device 1 is large. FIG. 7 is a diagram showing an example of the amount of reverse flow power when the power generation amount X of the solar power generation device 1 according to the first embodiment is small. The vertical axis shows the amount of power, and the horizontal axis shows time. As shown in FIG. 7, when the maximum power generation amount is small, the reverse flow energy amount XY becomes small although the attachment of the CT sensor 10 is normal, so that the difference with the threshold value α becomes small. There is a possibility that it may be erroneously determined that there is a defect in the installation of 10.

  In order to prevent the erroneous determination of the installation defect of the CT sensor 10 as described above due to the small amount of sunshine and the small amount of power generation X by the solar power generation device 1, the amount of power generation X by the solar power generation device 1 is measured From the results measured by the apparatus 20, the control circuit 6 is in a time zone where the amount of generated energy X is maximum (step S103: Yes), even though reverse power flow is occurring (step S104: Yes). If the generated energy amount X is small (step S105: Yes), the determination of the installation defect of the CT sensor 10 is not performed (step S109). Thereby, an erroneous determination can be prevented.

  When the amount of generated energy X by the solar power generation device 1 is small because the weather is bad and the amount of solar radiation is small, erroneous determination is made by adding correction to the threshold value α instead of simply performing determination as in step S109. It is also possible to make a judgment that has been prevented.

  By installing a sunshine meter, the control circuit 6 calculates the power amount β, which is the decrease amount of the generated power amount X expected to decrease due to the small amount of sunshine from the value of the sunshine meter, Correct to β.

  In the case of a household power generation system 100 having a small size of the solar power generation device 1, it is difficult to install a sunshine meter. In such a case, the control circuit 6 can also calculate the amount of power reduction β by obtaining the amount of sunshine from the Internet, for example, or estimating the amount of sunshine from the information of the weather forecast. The control circuit 6 can obtain such information via the communication circuit 8.

  Furthermore, the control circuit 6 can also estimate the decreasing amount of power β based on the instruction concerning the amount of backward flowable power amount transmitted from the power company in each area received by the communication circuit 8. If the weather in the area under the jurisdiction of the power company is fine, and it is predicted that the power generation capacity X will increase and the amount of reverse flow of power will increase, the amount of power that can be reverse flowed from each photovoltaic power generation device Instructs to limit to a small value. Therefore, when the amount of reverse flowable power instructed by the power company is small, it is estimated that the amount of power β to be reduced is small. Conversely, if the amount of reverse flowable power instructed by the power company is large, it is considered that the weather is bad and the amount of solar radiation decreases, and the amount X of generated energy decreases, so the power amount β to be reduced is estimated to be large. Be done. However, the amount of reverse flowable power instructed by the power company may not be available simply because it may be affected simply by the amount of power used by the jurisdiction and the installation status of the solar power generation equipment. It is necessary to check the status of

  On the other hand, when the power consumption Y consumed by the home load 3 temporarily increases, or when the power consumption Y increases with an increase in the number of electrical products, the reverse flow power amount XY decreases, so Also in the case, it is conceivable that an erroneous determination occurs. When an increase in the power consumption Y in the home is predicted in advance, the threshold α is corrected to α-γ using the increase γ in the power consumption Y. Thereby, the erroneous determination of the installation defect of the CT sensor 10 is prevented.

  The increase amount γ of the power consumption amount Y can be set by the remote controller 9 or the like. If the power consumption amount Y is temporarily increased, the user can set an increase amount γ and a period during which the amount is increased. A restriction is imposed on the period that can be set by the user and the number of times set so that the user can not arbitrarily change it. If the power consumption Y permanently increases, only the installer can set and change the value protected by a password or the like.

  FIG. 8 is another flowchart showing a processing procedure executed by the control circuit 6 according to the first embodiment to detect a mounting defect of the CT sensor 10.

  In FIG. 8, even when the amount of power generation X by the solar power generation device 1 is small because the weather is bad, or even when the amount of power consumption Y consumed by the home load 3 is temporarily increased, Instead of not determining the installation defect of the CT sensor 10, the threshold α is corrected to detect the installation defect of the CT sensor 10. In the following, in the flowchart of FIG. 8, points different from FIG. 5 will be described.

  In step S105 of FIG. 8, the control circuit 6 determines whether the generated power amount X measured by the generated power amount measuring device 20 is small. When the control circuit 6 determines that the generated power amount X is small (step S105: Yes), the control circuit 6 corrects the threshold value α with the decreasing power amount β (step S110). Specifically, the control circuit 6 subtracts β from the threshold α to set α-β as a new threshold. After step S110 and when the control circuit 6 determines that the generated energy amount X is not small (step S105: No), the process proceeds to step S111.

  In step S111, the control circuit 6 determines whether the power consumption amount Y increases. Since the power consumption amount Y increases and the period thereof is set in advance as described above, the control circuit 6 determines based on the setting. When the control circuit 6 determines that the power consumption amount Y increases (step S111: Yes), the control circuit 6 corrects the threshold value α or the threshold value α-β with the increase amount γ of the power consumption amount Y (step S112). In step S112, when the process does not go through step S110, the control circuit 6 subtracts γ from the threshold α to set α-γ as a new threshold. In step S112, when the process goes through step S110, the control circuit 6 subtracts γ from the threshold α-β to set α-β-γ as a new threshold. When the control circuit 6 determines that the power consumption amount Y does not increase after step S112 (step S111: No), the process proceeds to step S113.

  In step S113, control circuit 6 determines whether or not the amount of backward flow power is greater than a threshold. The threshold value used in step S113 is α that is not corrected if it does not pass through steps S110 and S112. When only step S110 is performed, the threshold is α-β. When only step S112 is performed, the threshold is α-γ. When both steps S110 and S112 are performed, the threshold is α-β-γ.

  When the control circuit 6 determines that the backward flow power amount is larger than the above-described threshold (step S113: Yes), the control circuit 6 determines that the attachment of the CT sensor 10 is normal (step S107). On the other hand, when the control circuit 6 determines that the backward flow power amount is smaller than the above-described threshold (step S113: No), the control circuit 6 determines that the CT sensor 10 is improperly attached (step S108).

  The merits of the flowchart of FIG. 8 will be specifically described below.

  If the weather is bad, the amount X of power generated by the solar power generation device 1 decreases from 5.0 kW to 3.5 kW, but the power consumption Y consumed by the home load 3 remains unchanged at 2.5 kW. The tidal power amount XY is 3.5 kW-2.5 kW = 1.0 kW. Therefore, since the reverse flow power amount is smaller than the threshold 2.0 kW while the threshold α remains 2.0 kW, the control circuit 6 determines that there is a defect in the installation of the CT sensor 10 (step S108). In order to prevent this, when the control circuit 6 determines that the generated power amount X is small (step S105: Yes), if the power amount β to be decreased is temporarily set to 1.5 kW, the threshold value is α-β = 2.0 kW −1.5 kW = 0.5 kW (step S110). As a result, since the reverse flow power amount becomes larger than the threshold value, it is possible to prevent the erroneous determination of the installation defect of the CT sensor 10. Here, the amount of electric power β to be decreased is set based on various information obtained from the pyranometer described above or via the Internet and the like.

  When the power consumption amount Y consumed by the home load 3 temporarily increases (step S111: Yes), the control circuit 6 corrects the threshold with the increase amount γ of the power consumption amount Y (step S112). When the power generation amount X by the solar power generation device 1 is 5.0 kW and the power consumption Y consumed by the indoor load 3 increases from 2.5 kW to 3.2 kW, the reverse flow power amount XY = 5.0 kW-3.2 kW = 1.8 kW. Therefore, since the reverse flow power amount is smaller than the threshold 2.0 kW while the threshold α remains 2.0 kW, the control circuit 6 determines that there is a defect in the installation of the CT sensor 10 (step S108). In order to prevent this, when the control circuit 6 determines that the power consumption Y increases (step S111: Yes), if the increase γ in the power consumption Y is set to 0.7 kW of the increase in home power consumption. The threshold value is α-γ = 2.0 kW−0.7 kW = 1.3 kW (step S112). As a result, since the reverse flow power amount becomes larger than the threshold value, it is possible to prevent the erroneous determination of the installation defect of the CT sensor 10.

  A decrease in the amount of power generation X due to bad weather and a temporary increase in the amount of power consumption Y in the home may occur simultaneously. When the power generation amount X decreases from 5.0 kW to 3.5 kW and the power consumption Y increases from 2.5 kW to 3.2 kW, the power consumption β to be decreased is 1.5 kW and the power consumption Y increases γ is 0.7 kW. In this case, the reverse flow power amount is XY = 3.5 kW-3.2 kW = 0.3 kW. And although a threshold turns into a negative value with alpha-beta-gamma = 2.0 kW-1.5 kW-0.7 kW =-0.2 kW, it is considered as a threshold of judgment as it is. When the value of the threshold becomes negative, it is judged by the control circuit 6 that the attachment of the CT sensor 10 is normal if the reverse power flow occurs, that is, if the value of the reverse flow power amount is a positive value (Step S107).

  The power conditioner 2 has a function of notifying the user that there is a defect in the installation of the CT sensor 10 when the control circuit 6 determines that there is a defect in the installation of the CT sensor 10. Specifically, the control circuit 6 controls the CT sensor 10 by displaying on the display unit 21 of the main body of the power conditioner 2 such as a light emitting diode (LED) or a liquid crystal display (LCD) or the display unit 91 of the remote controller 9. Inform the user that there is a defect in the installation of When displaying on the display unit 91, information that the installation method of the CT sampler 10 is incorrect is transmitted from the display information output terminal 102 to the remote controller 9. In addition, the user may be notified by an alarm that a connection device such as the main body of the power conditioner 2 or the remote controller 9 is defective in the attachment of the CT sensor 10. By notifying the user that there is a defect in the installation of the CT sensor 10, correction of the defect can be promoted.

  If the control circuit 6 determines that there is a defect in the installation of the CT sampler 10, the power conditioner 2 stops the reverse power flow, that is, stops selling power and the power exceeding the amount of power capable of reverse flow is reverse power Avoid the failure of the system 4 due to Furthermore, when the control circuit 6 determines that there is a defect in the installation of the CT sancer 10, the power conditioner 2 cuts off the electrical connection between the solar power generation device 1 and the power conditioner 2. Stop the acceptance of generated power. By stopping the reception of the generated power, reverse power flow, that is, selling power is also stopped.

  In addition, when the control circuit 6 determines that there is a defect in the installation of the CT sampler 10, the power conditioner 2 notifies the user at the same time as stopping the sale of electricity and stopping the acceptance of the generated power by the photovoltaic device 1. You do not have to do it. After a predetermined time has elapsed since the control circuit 6 determined that there is a defect in the installation of the CT sampler 10, the power conditioner 2 stops selling electricity and stops the acceptance of the generated power by the solar power generation apparatus 1 It may be set. This makes it possible to avoid the occurrence of a problem caused by stopping the reception of the generated power during the daytime when the user is often absent. In this case, the user is prompted to correct the installation defect by confirming the notification of the installation defect of the CT sensor 10 at night at home, and the installation defect of the CT sensor 10 is not resolved even over the next day or several days In the case, the power conditioner 2 stops the reception of the generated power by the solar power generation device 1.

  The power conditioner 2 is controlled by a control device such as a microcomputer. FIG. 9 is a block diagram showing the configuration of the microcomputer 200 according to the first embodiment. The power conditioner 2 is provided with a control device such as a microcomputer 200. The microcomputer 200 includes a central processing unit (CPU) 201 that executes control of the power conditioner 2, a random access memory (RAM) 202 that the CPU 201 uses for a work area, and a read only memory (ROM) that stores programs and data. 203, I / O (Input / Output) 204 which is hardware for realizing the function of the communication circuit 8, and a peripheral device 205 including an oscillator for generating a clock. The CPU 201 implements the function of the control circuit 6 by reading and executing the program stored in the ROM 203. That is, the microcomputer 200 includes the ROM 203 for storing a program that results in the steps of the flowchart of FIG. 5 or FIG. 8 being executed. Also, it can be said that this program causes the computer to execute the operation procedure by the control circuit 6.

  Although the control circuit 6 may use an analog current output signal output from the CT sensor 10 as a current value signal for obtaining reverse flow power, the analog current output signal is analog-digital in the power conditioner 2. You may use the digital signal obtained by converting. Also, the control circuit 6 may use both an analog current output signal and a digital signal to determine the amount of reverse flow power. Therefore, the control circuit 6 determines the amount of backward flow power based on at least one of the analog current output signal and the digital signal. Since the power conditioner 2 is controlled by a digital signal using a control device such as the microcomputer 200, the circuit configuration and control can be facilitated by using the digital signal.

  If the CT sensor 10 is correctly attached, it is possible to equally distribute the amount of power that can be reversely flowed among the plurality of photovoltaic power generation devices. According to the power generation system 100 according to the first embodiment, the power conditioner 2 can detect the installation defect of the CT sun sensor 10 by a simple mechanism and notify the user of the defect. As a result, the installation defect of the CT sensor 10 is improved, and the amount of power more than the power company's instruction flows backward to prevent the power transmission equipment of the power company from generating a fault, and the amount of power that can be reversed Fair distribution of Since the power generation system 100 according to the first embodiment uses equipment basically provided to the solar power generation system, it is possible to realize the above function without increasing the cost.

Second Embodiment
In the first embodiment, the control circuit 6 finally determines that the method of installing the CT sampler 10 is incorrect by comparing the reverse flow power amount with the threshold value. The configuration of the power generation system 100 according to the second embodiment is the same as that of FIG. 1, but in the control circuit 6 of the second embodiment, the installation method of the CT sun sensor 10 is incorrect in a method different from the first embodiment. In other words, it is determined that the installation is defective. Specifically, the control circuit 6 of the second embodiment can determine that the mounting direction of the CT sensor 10 is reverse, that is, reverse.

  In the control circuit 6 according to the second embodiment, when the amount X of power generation measured by the power generation amount measuring device 20 increases and the reverse flow power amount XY calculated based on the current value measured by the CT sensor 10 decreases Determines that the mounting direction of the CT sensor 10 is reverse.

  Further, in the control circuit 6 according to the second embodiment, the power generation amount X measured by the power generation amount measuring device 20 decreases and the reverse flow power amount XY determined based on the current value measured by the CT sensor 10 increases. Also in this case, it is determined that the mounting direction of the CT sensor 10 is reversed.

  The above-described determination operation by the control circuit 6 of the second embodiment is also realized by the CPU 201 executing a program stored in the ROM 203.

  When the control circuit 6 determines that the mounting direction of the CT sensor 10 is reverse, the control circuit 6 displays the display unit 21 of the main body of the power conditioner 2 such as an LED or LCD or the display unit 91 of the remote controller 9. Notifies the user that the mounting direction of the CT sensor 10 is reversed. When displaying on the display unit 91, information that the installation method of the CT sampler 10 is incorrect is transmitted from the display information output terminal 102 to the remote controller 9. In addition, the connecting device such as the main body of the power conditioner 2 or the remote controller 9 may notify the user that the mounting direction of the CT sensor 10 is reversed by an alarm. By notifying the user that the installation direction of the CT sensor 10 is reverse, it is possible to prompt the correction of the installation defect.

  If the control circuit 6 determines that the mounting direction of the CT sampler 10 is reverse, the power conditioner 2 stops reverse power flow, that is, stops selling power and the power exceeding the amount of power capable of reverse flow is reversed. Avoid the failure of the system 4 due to the power flow. Furthermore, when the control circuit 6 determines that the mounting direction of the CT sun sensor 10 is reverse, the power conditioner 2 cuts off the electrical connection between the solar power generation device 1 and the power conditioner 2 Stop the acceptance of generated power.

  Moreover, when the control circuit 6 determines that the mounting direction of the CT sampler 10 is reverse, the power conditioner 2 notifies the user at the same time as stopping the sale of electricity and stopping the acceptance of the generated power by the photovoltaic power generation device 1. You do not have to do it. After a predetermined time has elapsed since the control circuit 6 determined that the mounting direction of the CT sampler 10 is reverse, the power conditioner 2 stops selling electricity and stops the acceptance of the generated power by the solar power generation apparatus 1 It may be set to This makes it possible to avoid the occurrence of a problem caused by stopping the reception of the generated power during the daytime when the user is often absent.

  According to the power generation system 100 according to the second embodiment, the power conditioner 2 can detect that the mounting direction of the CT sun sensor 10 is reverse by a simple mechanism and notify the user. As a result, the installation defect of the CT sensor 10 is improved, and the amount of power more than the power company's instruction flows backward to prevent the power transmission equipment of the power company from generating a fault, and the amount of power that can be reversed Fair distribution of Since the power generation system 100 according to the second embodiment uses equipment basically provided to the solar power generation system, it is possible to realize the above functions without increasing the cost.

  The configuration shown in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and one of the configurations is possible within the scope of the present invention. Parts can be omitted or changed.

  DESCRIPTION OF SYMBOLS 1 solar power generation device, 2 power conditioner, 3 indoor load, 4 systems, 5 inverter circuit, 6 control circuit, 7 protection circuit device, 8 communication circuit, 9 remote controller, 10 CT sensor, 20 generated energy measuring device, 21 , 91 display unit, 100 power generation system, 101 reverse power flow input terminal, 102 display information output terminal, 200 microcomputer, 201 CPU, 202 RAM, 203 ROM, 204 I / O, 205 peripheral device.

Claims (11)

A power conditioner that supplies generated power generated by the power generation apparatus to a system power supply,
A reverse power flow measurement unit which is measurement means for determining a reverse flow power amount which is a power amount of reverse flow from the power conditioner to the grid power supply;
Power generation system comprising
The power conditioner is
The controller has a control unit that determines that the installation method of the reverse flow measuring unit is incorrect when the average value or the integrated power amount of the reverse flow power amount in a fixed period is equal to or less than a preset threshold. Power generation system. Wherein the control unit, according to claim, characterized in said when it is determined that the backward flow measuring unit installation method is wrong, it is displayed on the display unit to be incorrect installation method of the backward flow measuring section 1 power generation system according to. The said display part is provided in the said power conditioner. The electric power generation system of Claim 2 characterized by the above-mentioned. The said display part is provided in the connection apparatus connected to the said power conditioner. The electric power generation system of Claim 2 characterized by the above-mentioned. Power generation system of claim 1 wherein when the control unit determines that the erroneous installation method of the backward flow measuring unit, wherein the power conditioner, characterized in that stopping the backward flow. The power generation system according to claim 5 , wherein the power conditioner stops the reverse flow after a predetermined time has elapsed after determining that the setting method of the reverse flow measurement unit is incorrect by the control unit. . Power generation system of claim 1 wherein when the control unit determines that the erroneous installation method of the backward flow measuring unit, wherein the power conditioner, characterized in that the stop accepting the generated power. 8. The power conditioner according to claim 7 , wherein the power conditioner stops receiving the generated power after a predetermined time has elapsed since the control unit determines that the installation method of the reverse flow measurement unit is incorrect. Power generation system. The output signal of the reverse flow measurement unit is an analog current output signal, and the control unit is based on at least one of the analog current output signal and a digital signal obtained by analog-digital conversion of the analog current output signal. The power generation system according to claim 1, wherein the reverse flow power amount is calculated. The power generation system according to claim 1, wherein the power conditioner includes a reverse flow input terminal that receives an output signal of the reverse flow measurement unit. The power conditioner is connected to the connection device, according to claim 4, wherein the information and installation of the backward flow measurement section is incorrect comprise a display information output terminal to be transmitted to the connected device The power generation system described in.

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