JP2016039671A - Monitor device for photovoltaic power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitor device for a photovoltaic power generation system that can display a state of charging or discharging of a storage battery in a simple method.SOLUTION: A monitor device for a photovoltaic power generation system comprises: a CT sensor 8 which detects a current flowing through a general load line 6, connecting a general load power distribution board 11 connecting with the photovoltaic power generation system, a system power source, and a general load 12, to a storage battery 4; a CT sensor 9 which detects a current flowing through an important load line 7, connecting an important load power distribution board 13 connecting with an important load 14 used in a case of a power failure preferentially to the general load 12, to the storage battery 4; a measurement device 3 which determines whether the storage battery 4 is in a charged state or discharged state based upon detection information of the CT sensors 8, 9; and a monitor device 5 which displays an in-charging state or in-discharging state of the storage battery 4.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a monitoring device for a photovoltaic power generation system.

In recent years, there has been a growing interest in reducing CO ₂ emissions, which cause global warming, and alternative energy alternatives to fossil fuels, which are expected to be depleted over time. In particular, solar power is a clean and inexhaustible energy source. The solar power generation system by is attracting attention. Monitor devices that are connected to a solar power generation system and display data such as generated power information indicating the power generation status are commercially available.

  The main information displayed by the monitor device includes information on the power generated by the solar module and converted from direct current to alternating current by the power conditioner, information on power purchased and sold with the power company, and power consumption used in the home. There is information. In general, the generated power information, the purchased / sold power information, and the consumed power information are measured by the measuring device and then sent to the monitor device for display. Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique regarding a power indicator that is connected to a power conditioner, a system power supply, and an electric device, and acquires and displays generated power and power consumption.

  Regarding the solar power generation system, a system that can incorporate a storage battery capable of storing the power generated by the solar module into the system and use the power stored at night or during a power outage will be desired.

JP 2014-32151 A

  However, according to the above-described conventional technology, there is a problem that even if a storage battery is connected to the system, information on charging / discharging of the storage battery cannot be acquired. In addition, even if a photovoltaic power generation system that supports storage batteries is used by connecting a storage battery from another manufacturer, the storage battery charge / discharge of storage batteries that do not have a common communication protocol or that have no communication function. There is a problem that the state of the battery cannot be grasped and the state of the storage battery cannot be displayed. It is necessary to cope with a system that stores the electric power generated by solar power generation, which is expected to increase in the future, in a storage battery.

  This invention is made | formed in view of the above, Comprising: It aims at obtaining the monitor apparatus for photovoltaic power generation systems which can display the charge or discharge state of a storage battery by a simple method.

  In order to solve the above-described problems and achieve the object, the present invention provides a current flowing through a general load line connecting a photovoltaic power generation system or a system power source and a general load distribution board connected to a general load, and a storage battery. Detecting a current flowing in an important load line connecting the first current sensor for detecting the critical load, the important load distribution board connected to the important load used in the event of a power failure over the general load, and the storage battery. A measuring device for determining whether the storage battery is in a charged state or a discharged state based on a second current sensor, detection information of the first current sensor and detection information of the second current sensor; And a monitor device that displays whether the storage battery is being charged or discharged based on the determination result of the measuring device.

  According to the present invention, there is an effect that the state of charge or discharge of the storage battery can be displayed by a simple method.

The figure which shows the example of a connection with the photovoltaic power generation system, the distribution board installed in the house, and a storage battery about the monitoring apparatus for photovoltaic power generation systems concerning Embodiment 1 The figure which shows the screen where the monitor device displays the state of the storage battery

  Hereinafter, embodiments of a monitor device for a photovoltaic power generation system according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1: is a figure which shows the example of a connection with the solar power generation system, the distribution board installed in the house, and the storage battery about the monitoring apparatus for solar power generation systems concerning this Embodiment.

  The solar power generation system includes a solar battery panel 1 and a power conditioner 2. The solar cell panel 1 is configured by installing a plurality of solar cell modules on the roof of a house and connecting the plurality of solar cell modules in series or in parallel. A power conditioner 2 is connected to the solar cell panel 1.

  The solar cell panel 1 receives sunlight and generates power to generate DC power. The power conditioner 2 converts the DC power generated by the solar cell panel 1 into AC power and outputs it. The power conditioner 2 is connected to a general load distribution board 11. The alternating current from the solar power generation system is consumed by a load in the house via a branch breaker (not shown) in the general load distribution board 11 and is charged by the storage battery 4.

  The measuring device 3 acquires generated power information in the solar power generation system by communication from the power conditioner 2. In addition, the measuring device 3 is a power purchase / purchase information that is information on power traded with a power company by a tidal point sensor 15 connected to a system power supply line 10 that connects the system power supply and the general load distribution board 11. To get. In addition, the measuring device 3 has a current value between the general load distribution board 11 and the storage battery 4 by a CT (Current Transformer) sensor 8 which is a first current sensor, and a CT sensor 9 which is a second current sensor. Information on the current value between the load distribution board 13 and the storage battery 4 is acquired.

  In the present embodiment, a case where the load in a house is divided into a general load and an important load will be described.

  The general load 12 is, for example, an air conditioner, a microwave oven, a washing machine, or the like, and is connected to the general load distribution board 11 and can be supplied with power from the solar power generation system, the system power supply, or the storage battery 4. The general load distribution board 11 is connected to the photovoltaic power generation system, the system power supply, the storage battery 4, the measuring device 3, and the general load 12.

  The important load 14 is, for example, a fluorescent lamp, a television, a refrigerator, and the like, connected to the important load distribution board 13, and connected from a system power source or a solar power generation system via a branch circuit (not shown) at the entrance of the storage battery 4. Power supply or power supply from the storage battery 4 is possible. The important load 14 is an important electrical device that is used with priority over the general load 12 during a power failure. The important load distribution board 13 is connected to the storage battery 4 and the important load 14.

  By separating the general load 12 and the important load 14, the storage battery 4 can supply power only to the important load 14 when the system power supply is interrupted.

  Hereinafter, a power supply line connecting the storage battery 4 and the general load distribution board 11 is called a general load line 6, and a power supply line connecting the storage battery 4 and the important load distribution board 13 is called an important load line 7.

  In the general load line 6, a charging current flowing from the system power source or the photovoltaic power generation system to the storage battery 4 through the general load distribution board 11 flows, and from the storage battery 4 to the general load 12 through the general load distribution board 11. In some cases, a discharge current flows. The normal load line 6 supplies power to the storage battery 4 by supplying power from the solar power generation system or the system power supply during normal charging operation, and supplies power from the storage battery 4 to the general load 12 during discharging operation. . Here, the solar power generation system and the system power supply serve as a power supply source to the general load distribution board 11 or the storage battery 4.

  A CT sensor 8 is connected to the general load line 6. The CT sensor 8 detects the current flowing through the general load line 6, determines the direction of the current, determines whether the general load 12 is in a power supply state or the storage battery 4 is charged in the current direction, and is charged. Monitor the current value for either direction or discharge direction.

  The important load line 7 is only when a discharge current from the storage battery 4 to the important load 14 flows through the important load distribution board 13. The important load line 7 normally supplies power to the important load 14 from the photovoltaic power generation system or system power source or the storage battery 4 as a power supply source, and supplies power from the storage battery 4 to the important load 14 at power failure. Do.

  A CT sensor 9 is connected to the important load line 7. The CT sensor 9 detects the current flowing through the important load line 7, but the important load line 7 is fixed to the power supply line only by supplying power to the important load 14 and is not used for charging. Only the current value fed from the storage battery 4 to the important load 14 is monitored.

  The CT sensor 8 constantly monitors the current direction and current value of the general load line 6, and the CT sensor 9 constantly monitors the current value of the important load line 7. The measuring device 3 acquires information on the current value at the time of charging or discharging of the general load line 6 from the CT sensor 8, and acquires information on the current value at the time of discharging of the important load line 7 from the CT sensor 9. . The measuring device 3 determines whether the storage battery 4 is in a charged state or a discharged state using each current value according to the following equation.

When the current direction of the general load line 6 is the charging direction from the general load distribution board 11 to the storage battery 4 Current value of the general load line 6−Current value of the important load line 7> 0 ⇒ Charging state Current value of the general load line 6 -Current value of important load line 7 <0 ⇒ Discharge state Current value of general load line 6-Current value of important load line 7 = 0 ⇒ No charge / discharge state

When the current direction of the general load line 6 is the discharge direction from the storage battery 4 to the general load distribution board 11 ⇒ Discharge state

  The measuring device 3 performs a determination process according to the above equation, and transmits state data indicating whether the storage battery 4 is in a charged state or a discharged state to the monitor device 5 by communication. In addition, the measuring device 3 may transmit the state data indicating the no charge / discharge state to the monitor device 5 through communication.

  Note that the determination process may be performed by the monitor device 5 instead of the measurement device 3. In this case, the measuring device 3 transmits the acquired information on the current direction and current value of the general load line 6 and the information on the current value of the important load line 7 to the monitor device 5, and the monitor device 5 determines according to the above formula. Process.

  The monitor device 5 displays a state of charging or discharging the storage battery 4 based on the state data determined by the measuring device 3 or the own device. In addition, the monitor apparatus 5 may display also about a state without charging / discharging. FIG. 2 is a diagram showing a screen on which the monitor device 5 displays the state of the storage battery 4. A state in which the monitor device 5 displays information on the total accumulated power generation amount, the generated power indicating the current power generation amount, and the storage battery state information indicating the current state of the storage battery 4 for the current system state. It is shown. The monitor device 5 can indicate the state of the storage battery 4 in addition to the conventional total accumulated power generation amount and generated power. In FIG. 2, “charging” when the storage battery 4 is in a charged state is displayed as an example, but “discharged” is displayed when the storage battery 4 is in a discharging state. Further, when the storage battery 4 is in a state without charge / discharge, “no charge / discharge” may be displayed.

  As described above, according to the present embodiment, the CT sensor 8 detects the current flowing through the general load line 6 that connects the general load distribution board 11 and the storage battery 4, and the CT sensor 9 detects the important load. The current flowing through the important load line 7 that connects the distribution board 13 and the storage battery 4 is detected, and the measurement device 3 determines whether the storage battery 4 is in a charged state or a discharged state based on detection information of the CT sensors 8 and 9. The monitoring device 5 displays that the storage battery 4 is being charged or discharged based on the determination result of the measuring device 3. Thereby, when using the storage battery of another manufacturer, even if there is no common communication protocol or the storage battery does not have a communication function, the storage battery can be displayed during charging or discharging with a simple configuration. In other words, the monitoring device for the photovoltaic power generation system can determine and display the state of the storage battery 4 only by using the information on the current detected by the CT sensors 8 and 9.

Embodiment 2. FIG.
In the first embodiment, the case where the load in the house is divided into the general load 12 and the important load 14 has been described. However, a configuration in which the load is not divided into the general load 12 and the important load 14 is also possible.

  When the load in the house is not divided into the general load 12 and the important load 14, the system configuration is a configuration in which the important load distribution board 13, the important load line 7, and the CT sensor 9 are deleted from FIG. 1. The important load 14 is connected to the general load distribution board 11 in the same manner as the general load 12.

  In this case, the measuring device 3 determines that the state of the storage battery 4 is being charged based only on the monitoring result in the current direction by the CT sensor 8 connected to the general load line 6 between the general load distribution board 11 and the storage battery 4. Or it can be determined whether it is discharging. Note that, similarly to the first embodiment, the monitor device 5 may perform the determination process. The monitor device 5 displays a state of charging or discharging the storage battery 4 based on the determination by the measuring device 3 or its own device.

  Even in a configuration that is not divided into the general load 12 and the important load 14, the same effect as in the first embodiment can be obtained.

Embodiment 3 FIG.
In the monitor device for the photovoltaic power generation system, the current direction and the current value can be monitored by the CT sensor 8 and the CT sensor 9, so that not only “charging” or “discharging” is displayed on the monitoring device 5, but also the current charging It is also possible to display numerical information about the amount (charge current value) or the discharge amount (discharge current value).

  The numerical information may not be an actual numerical value but may be a relative level display in which the degree of charge or discharge can be compared, for example, a three-level level meter display. The level meter display is not limited to three levels.

  Thereby, there is an effect that not only the state of being charged or discharged but also the amount of charge or discharge can be grasped.

  Here, the measuring device 3 knows how much electrical energy is stored in the storage battery 4 even if the charge amount currently charged in the storage battery 4 or the discharge amount currently discharged from the storage battery 4 is known. I can't figure it out. Therefore, the measuring device 3 uses the information on the amount of charge or discharge by the CT sensor 8 and the information on the amount of discharge by the CT sensor 9 to integrate from the initial state of the storage battery 4, whereby the storage amount (Ah) of the storage battery 4 is obtained. ) Can be calculated and the monitor device 5 can display the charged amount. Note that the storage amount display is not only a numerical display, but also a relative level display that shows the degree of the storage amount, for example, a three-level level meter display that indicates the remaining battery capacity in a mobile phone or smartphone. Good. The level meter display is not limited to three levels.

  The measuring device 3 uses the current value by the CT sensors 8 and 9, the voltage value to be separately measured, and the charge power amount or the discharge power amount depending on the time factor with respect to the initial value of the power storage amount of the storage battery 4, for example “0” By accumulating, the amount of electricity stored at a certain time, for example, a Wh equivalent value can be obtained. For the voltage value to be measured separately, the measuring device 3 may use, for example, a voltage value measured for the power supplied from the general load distribution board 11, but is not limited thereto.

  When the monitor device 5 displays the storage amount of the storage battery 4 with a numerical value or a level meter display, the user can easily grasp the state of the electrical energy stored in the storage battery 4. Note that, similarly to the determination processing in the first and second embodiments, the monitor device 5 may obtain information necessary for calculating the storage amount from the measurement device 3 and obtain the storage amount by itself.

  Although there is a merit that the storage amount of the storage battery 4 can be calculated with a simple configuration and a simple calculation, there may be a measurement error, a calculation error, or a shift in the storage amount due to natural discharge of the storage battery 4, and the storage battery 4 gradually. It is expected that the amount of electricity stored will be unreliable.

  For this reason, in the measuring device 3, it is effective to correct the value of the storage amount of the storage battery 4 calculated as necessary for the deviation of the storage amount of the storage battery 4. For example, in a house, only the storage battery 4 is charged, and the storage battery 4 is brought into a fully charged state. When the storage amount obtained by calculation exceeds 100% of the storage battery capacity, the measuring device 3 determines that the storage amount is deviated from the true value, and corrects the storage amount to a value corresponding to 100% of the storage battery capacity. To do. Or in a house, only the discharge from the storage battery 4 is implemented and the storage battery 4 is made into a fully discharged state. The measuring device 3 determines that it is deviated from the true value when the storage amount obtained by calculation is 0 or less, and corrects the storage amount to 0.

  In the measuring device 3, by performing the above correction, it is possible to obtain a reliable charged amount with little deviation and display it on the monitor device 5. In addition, when the monitor apparatus 5 is calculating the storage amount, the monitor apparatus 5 may perform correction.

  DESCRIPTION OF SYMBOLS 1 Solar cell panel, 2 Power conditioner, 3 Measuring apparatus, 4 Storage battery, 5 Monitor apparatus, 6 General load line, 7 Important load line, 8, 9 CT sensor, 10 System power line, 11 General load distribution board, 12 General load, 13 Important load distribution board, 14 Important load, 15 Tidal point sensor.

Claims (7)

A first current sensor for detecting a current flowing in a general load line connecting a photovoltaic power generation system or a system power source and a general load and a general load distribution board connected to a storage battery;
A second current sensor for detecting a current flowing in an important load line connecting an important load distribution board connected to an important load used in preference to the general load at the time of a power failure, and the storage battery;
A measuring device for determining whether the storage battery is in a charged state or a discharged state based on detection information of the first current sensor and detection information of the second current sensor;
Based on the determination result of the measuring device, a monitor device that displays charging or discharging about the state of the storage battery;
A monitor device for a photovoltaic power generation system, comprising: The measuring device has the storage battery in a charged state or a discharged state based on information on a current direction and a current value detected by the first current sensor and a current value detected by the second current sensor. To determine whether
The monitoring device for a photovoltaic power generation system according to claim 1. A current sensor for detecting a current flowing in a load line connecting a photovoltaic power generation system or a system power source and a distribution board connected to a load, and a storage battery;
A measuring device for determining whether the storage battery is in a charged state or a discharged state based on detection information of the current sensor;
Based on the determination result of the measuring device, a monitor device that displays charging or discharging about the state of the storage battery;
A monitor device for a photovoltaic power generation system, comprising: The measurement device determines whether the storage battery is in a charged state or a discharged state based on information on a current direction and a current value detected by the current sensor.
The monitoring device for a photovoltaic power generation system according to claim 3. The measurement device calculates a charge amount to the storage battery or a discharge amount from the storage battery based on information on a current value to the storage battery or a current value from the storage battery,
The monitor device displays the charge amount or the discharge amount with a numerical value or a relative level display.
The monitoring device for a photovoltaic power generation system according to any one of claims 1 to 4. The measuring device calculates the storage amount of the storage battery by integrating the charge amount and the discharge amount,
The monitor device displays the amount of electricity stored;
The monitoring device for a photovoltaic power generation system according to claim 5. The measuring device corrects the charged amount when the storage battery is in a fully charged state to a value corresponding to the fully charged state, or the charged amount when the storage battery is in a fully discharged state. Correct to the value corresponding to the state,
The monitoring device for a photovoltaic power generation system according to claim 6.

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