JP2013021754A - Demand monitoring control device using renewable energy power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device capable of suppressing yearly electricity charge not only by selling the total quantity of electricity generated by renewable energy to a power proprietor, but also by controlling a demand value of load equipment to a target demand value or less, using generated electricity on a load equipment side when necessary.SOLUTION: A system monitor control apparatus is configured so that a demand value in load equipment is controlled to a target demand value or less by switching the electricity generated by a renewable energy power generation system between use in the load equipment to be used for electricity generated by the renewable energy power generation system and power selling to a power proprietor.

Description

  The present invention relates to a system monitoring and control apparatus using a renewable energy power generation system. More specifically, by monitoring the amount of power used by power users, switching between use on the power user side and selling power to the power company for electricity generated by renewable energy such as sunlight, The present invention relates to an apparatus for suppressing the maximum power amount (demand value) of a power user to a certain value or less.

  In power usage contracts, demand contracts are generally made. In this demand contract, charges per unit power are set in stages according to the power consumption in the demand time period, and the higher the power consumption in the demand time period, the higher the charge per unit power amount. It is a contract. Therefore, since the electricity bill per unit power amount can be lowered by suppressing the maximum power amount, various techniques for suppressing or monitoring the demand value have been disclosed (Patent Document 1, Patent Document 2, Patent Document 3). ).

  Renewable energy, on the other hand, refers to energy that can be extracted using natural phenomena and can be regenerated even after it has been used, and that does not run out. Typical renewable energies include sunlight, wind power, and geothermal heat. It is difficult to say that this renewable energy is fully utilized in Japan. For example, in electricity, except for hydroelectric power generation, power generation by renewable energy is only about 1%, and further utilization of renewable energy is required.

One of the most widely used renewable energy is sunlight, and a photovoltaic power generation system using this sunlight is widely used at each household level. A photovoltaic power generation system is a device that converts DC power generated by a photovoltaic power generator into AC power similar to commercial power using an inverter circuit, etc., and is connected (connected) to the commercial power system to provide home appliances, etc. A system that supplies power to load equipment. In the photovoltaic power generation system, a system for purchasing the remaining surplus power consumed by the load equipment (hereinafter referred to as “surplus purchasing system”) has been established and the spread of the photovoltaic power generation system is promoted. The Cabinet decided the “Special Measures Bill on Renewable Energy Electricity Procurement by Electric Power Companies” with the purpose of further expanding the use of electricity. In this bill, the current surplus purchase system will be changed, and a system will be set up in which the total amount of electricity generated by the photovoltaic power generation system is purchased by the jurisdiction power company (hereinafter referred to as the “total purchase system”).

JP2009-240049 JP2009-240050 JP 2010-237119 A

  In this total purchase system, the purchase price of electricity generated by renewable energy is scheduled to be higher per unit amount than electricity used. Therefore, there is a greater monetary advantage compared to the surplus purchase system so far. In other words, there is a sufficient merit even if the electric power supplier who buys the entire amount of generated electricity is purchased.

  However, the inventors have come up with a way to make better use of electricity generated by renewable energy. In other words, not only the total amount of electricity generated by renewable energy is sold to electric power companies, but when necessary, the generated electricity is used on the load equipment side to keep the load equipment demand value below the target demand value. This is a way to reduce the annual electricity bill. As a result of earnest research, the inventors have invented a system monitoring and control apparatus for realizing this method. That is, the apparatus according to the present invention has the following configuration.

  The first configuration in the present invention is to use electricity generated by a renewable energy power generation system for use in a load facility that is a target of use of electricity generated by the renewable energy power generation system and for selling power to an electric power company. A system monitoring and control device for switching the demand value in the load facility to a target demand value or less by switching, wherein the system monitoring and control device transmits at least power generation information transmitted from the renewable energy power generation system. From a renewable energy power generation system information receiving unit that receives power, a power flow switching information receiving unit for receiving power flow switching information from a power flow switching unit, and a power meter that records the power usage status of the load facility A power meter information receiving unit for receiving the load facility power usage information of the load, and the load A predicted demand value calculation unit for calculating a predicted demand value in a predetermined demand time period in the load facility using the power supply usage information, and a demand for comparing and comparing the predicted demand and the target demand value in the load facility A peak determination unit, and a control information transmission unit for transmitting control information for either power sale to a power company or use of load equipment to the power flow switching unit according to the demand peak determination result, It is a system monitoring and control device.

  According to a second configuration of the present invention, the predicted demand value calculation unit further includes a first demand calculation unit that calculates a demand value per unit time shorter than the demand time period, and a demand time period including a calculation time point. Consumption using the second demand calculation unit that calculates the accumulated demand value at the calculation time by summing the first demand values from the start time to the calculation time, and the first demand value that is relatively recent from the calculation time A prediction demand calculation unit for calculating a predicted demand value by calculating a power change amount, calculating a demand value from a calculation time point to the end of a demand time period, and adding the second demand value. 1 is a system monitoring control apparatus according to the first embodiment.

The present invention provides a method for more utilizing renewable energy. That is, the system monitoring and control device according to the present invention not only sells the total amount of electricity generated by renewable energy to the power utility, but also uses the electricity generated when necessary to load the load facility. By keeping the demand value of the equipment below the target demand value, it can be expected to reduce the annual electricity bill.

System configuration example using system monitoring control device according to the present invention Example of system monitoring and control apparatus according to the present invention Example of monitoring control flow performed by system monitoring control apparatus according to the present invention Example of forecast demand calculation processing

  Here, the system monitoring control apparatus according to the present invention will be described in detail with reference to the drawings. However, as a matter of course, the contents of the present invention are not limited to the following.

  FIG. 1 shows an example of a system configuration using the system monitoring control apparatus according to the present invention. In this system configuration example, a photovoltaic power generation system is used as a renewable energy power generation system. This system configuration example is composed of a monitoring control unit 1, a photovoltaic power generation system 2, a load facility 3, a power provider facility facility 4, and an integrated management unit 5. The monitoring control unit 1 acquires information on each configuration, When appropriate, the power flow switching control information is transmitted to the power utility facility equipment 4. As a result, the electricity generated by the photovoltaic power generation system 2 can be used in the load facility 3 (hereinafter “non-power sale control”) or sold to a power company (hereinafter “power sale control”). It is possible to switch. Information collected and calculated by the monitoring control unit 1 is transmitted to the integrated management unit 5 at appropriate times via the network. Basically, the monitoring control unit 1, the photovoltaic power generation system 2, the load equipment 3, the power utility facility equipment 4, and these four configurations (hereinafter referred to as “monitoring control unit”) are installed in each building, for example. Although they are relatively close to each other, there is no problem with the integrated management unit 5 even in a remote place, and a plurality of monitoring control units can be managed simultaneously.

  The monitoring control unit 1 includes a power flow switching unit 11 and a system monitoring control device 12. These may be configured as separate devices, or may be configured as an integrated device.

  The system monitoring and control apparatus 12 acquires information from each device, and performs a time-dependent calculation of a predicted demand value in a predetermined demand time period and a magnitude comparison (determination process) between the predicted demand value and the target demand value. Have. In addition, the main role is to transmit power flow switching control information to the power flow device 11 in accordance with the result of the determination process.

The system monitoring controller 12 will be further described with reference to FIG. FIG. 2 is a configuration example of the system monitoring control device 12.
The power flow switching information receiving unit 122 receives the power flow switching information from the power flow switching unit 11. The solar power generation system information receiving unit 123 receives information such as the amount of power generated transmitted from the solar power generation system. The power meter information receiving unit 124 receives information related to power usage in the load facility 3 from a power meter installed by a power company or the like.
The predicted demand value calculation unit 125 displays various information obtained from the receiving unit and default information registered in advance by the external recording unit 13, for example, information such as a target demand value of load equipment, CT ratio, and VT ratio. Used to calculate the predicted demand value over time for each demand period.
The demand peak determination unit 126 performs demand peak determination and demand peak release determination described later. That is, the calculated predicted demand value and the target demand value are compared and determined.
The control information transmission unit 127 transmits power sale / non-power sale control information to the power flow switching unit 11 according to the comparison / determination result.

Subsequently, the power flow switching unit 11 receives power flow information (power sale or non-sell control information) from the power receiving facility 42 and transmits the power flow information to the system monitoring control device 12. In addition, the main role is to receive the power flow switching control information from the system monitoring controller 12 and to instruct the power receiving facility 42 to switch the power flow information.
The external recording unit 13 plays a role of recording / saving various data and inputting / outputting data to / from the system monitoring control device 12. The information to be recorded is not particularly limited. For example, information on the photovoltaic power generation system (number of solar modules, etc.), target demand value in the load facility 3 described later, CT ratio or VT ratio, pulse Rate and so on. In addition, various information acquired by the system monitoring control device 12, the calculated first demand value, the predicted demand value, and the like are also recorded over time.

  Next, a system flow of the system monitoring control apparatus according to the present invention will be described with reference to FIG.

  When the system monitoring control is started (S121), the power flow switcher information reception process is started. That is, the power flow switch information is transmitted from the power flow switch 11 and received by the system monitoring controller 12 (S122). As this power flow switching device information, the power flow information received by the power flow switching device 11 from the power receiving equipment 42, that is, whether it is a flow of power sales to the power company (power sales control), or used in the load equipment 3 (Non-power-selling control) information is essential information. In addition, various information, for example, information on whether or not the power flow switching device 11 is operating normally can be transmitted to the system control monitoring device 12. In this case, the power flow switching device 11 operates normally. If it is determined that the error has not occurred, error information is transmitted from the system monitoring controller 12 to the integrated management unit 5 (not shown).

  Next, the photovoltaic power generation system information is transmitted from the power conditioner 23 of the photovoltaic power generation system 2 and received by the system monitoring control device 12 (S123). The solar power generation system information is mainly the amount of electricity per unit time generated by the solar power generation system 2, but can also receive incidental information such as temperature and solar radiation. Similarly to the power flow switch 11, the system operation information and the like can be received.

  Furthermore, the power meter information is transmitted from the power meter 41 and received by the system monitoring control device 12 (S124). As reception information at this time, information related to the power consumption of the load facility 3 included in the power meter is essential reception information, and examples thereof include demand pulse (Pulse / h) information. In this case, when demand pulse information cannot be received normally, error information is transmitted from the system monitoring controller 12 to the integrated management unit 5 (not shown).

  The system monitoring control device 12 starts the predicted demand value calculation process using the various information acquired by the series of processes and the registered information recorded in the external recording unit 13 (S125). The predicted demand value is an estimated demand value in a demand time period that includes the time at the time when the predicted demand value is calculated, and is defined as a value calculated with validity from various information. When calculating the predicted demand value, various calculation methods can be used because the calculation formula varies depending on the configuration of the equipment, the data information that can be acquired, and the like.

The predicted demand calculation process will be described with reference to FIG.
FIG. 4 shows an example in which the predicted demand calculation process is calculated by three steps: a first demand value calculation process (S1251), a second demand value calculation process (S1252), and a predicted demand value calculation process (S1253).

In the first demand value calculation process (S1251), a demand value of a unit time that is sufficiently shorter than the demand time limit of 30 minutes is calculated over time. The calculated first demand value is sequentially recorded in the external recording unit 13, and is read by the system monitoring control device 12 for arithmetic processing at appropriate times.
Hereinafter, taking an example where the unit time is 1 minute, a 1-minute demand value is calculated for each hour (for example, 12:01, 12:02, 12:03,...) It is stored in the recording unit 13. The 1-minute demand value can be calculated by selecting an appropriate calculation formula as appropriate depending on the configuration of the device, the type of received data, and the like. For example, in the system configuration example of FIG. The following equation 1 is used to calculate the demand pulse information (Pulse / h), the CT ratio and VT ratio, and the pulse rate (Pulse / kWh) stored in the external recording unit 13.
(Formula 1)
First demand value (1 minute demand value, kW) = (Demand pulse total integrated value from 0 to 60 seconds per minute) x unit correction value x ((CT ratio x VT ratio) / pulse rate)
(The unit correction value is a value for correcting the time unit. In the above case, 60)

In the subsequent second demand value calculation process (S1252), the demand value from the demand time limit start time to the time of the calculation time within the demand time period including the time at which the operation is performed is calculated (for example, the demand time period is 12:00). If the time at the time of calculation is 12:15 from 01 to 12:30, the total value of demand values from 12:01 to 12:15). The second demand value can also be calculated by appropriately selecting an appropriate calculation formula depending on the configuration of the device and the type of received data. For example, in the case of the system configuration example of FIG. Is calculated by
(Formula 2)
Second demand value (kW) = (cumulative value of the first demand value from the demand start time to the calculation time point within the demand time limit) / (cumulative elapsed time until the calculation time point)

Further, the predicted demand value calculation process (S1253) can also be calculated by selecting an appropriate calculation formula depending on the configuration of the device, the type of received data, etc., for example, in the system configuration example of FIG. In this case, it is calculated in two steps.
First, as shown in the following formula 3, the change in power consumption value is calculated by integrating the first demand value calculated over time from the time of calculation to N minutes and dividing by N. kW / min) to calculate the power consumption trend.
(Formula 3)
Change in power consumption = ∫ (first demand value at time t minutes before calculation) dt / N (t is 1 to N)
Note that N is a value that can be set as appropriate, but is set as a relatively recent time at the time of calculation. That is, N is selected within a range in which the amount of power consumption change at the time of calculation can be reasonably calculated. If N is traced back, the amount of power consumption change at the time of calculation is not reflected, which is not preferable. Therefore, N can preferably be selected from 1 to 10 minutes.

Based on the calculated power consumption change amount, the power consumption amount (predicted demand value) at the time of calculation is calculated by the following equation 4. The remaining demand time is defined as (current demand time end time−time at the calculation time) for the current demand time period including the time at the calculation time.
(Formula 4)
Predicted demand value (kW) = second demand value + (power consumption change x demand time remaining)

  After the series of predicted demand value calculation processes, a demand peak determination process (S126) is performed. Thereby, the calculated predicted demand value is compared with the target demand value of the load facility 3. Here, the target demand value refers to a demand value to be achieved below that in the load facility 3 and can be set as appropriate. For example, the value of the demand contract in the load facility 3 may be set as the target demand value, or the value of 95% of the value of the demand contract can be set as the target demand value by taking the safety factor.

If the target demand value is less than or equal to the predicted demand value, it is determined that demand peak has been detected. That is, it means that there is a high possibility that the electric power supplied from the electric power company at the load facility 3 exceeds the target demand value. By this demand peak detection, non-power sale control information is transmitted from the system monitoring controller 12 to the power flow switch 11 (S127). As a result, the power flow switching device 11 transmits power flow switching information to the power receiving facility 42, and the electricity generated by the photovoltaic power generation system 2 flows from the power meter 41 side to the load facility 3 side. Become. Thereby, the electricity generated by the solar power generation system 2 is preferentially used, and the amount of electricity used supplied from the electric power company can be suppressed.
When the target demand value exceeds the predicted demand value, it is determined that the demand peak is not detected. That is, it means that there is a low possibility that the electric power supplied from the electric power company at the load facility 3 will exceed the target demand value. Due to the non-detection of demand peak, the power monitoring control information is transmitted from the system monitoring controller 12 to the power flow switch 11 (S128).
As a result, the power flow switching device 11 transmits power flow switching information to the power receiving equipment 42, and the electricity generated by the photovoltaic power generation system 2 flows from the load equipment 3 side to the power meter 41 side and is sold. It will be.

  Note that, regarding the non-power sale control information transmission process (S127) and the power sale control information transmission process (S128), when the power receiving equipment 42 has already been in a control state instructing transmission, these processes are skipped. For example, the system monitoring control device 12 receives the power flow switching information indicating that the power receiving facility 42 is on the power selling side, based on the power flow switching information transmitted from the power flow switching device 11 in the power flow switching device information reception process S122. If the demand peak is not detected at this time, the process (S128) in which the system monitoring controller 12 transmits the power sale control information to the power flow switch 11 is skipped.

  When these non-power sale control information transmission processing (S127) and power sale control information transmission processing (S128) are completed, a series of information collected and calculated by the system monitoring control device 12 is used as the monitoring control information. To the integrated management unit 5. Thereby, about a series of systems with which the system monitoring control apparatus 12 is related, various information such as operation information of each apparatus / device, power generation information of the solar power generation system 2, temperature information / sunlight information, power sale / non-power sale control information, etc. This information can be acquired by the integrated management unit 5 and can be managed from a remote location.

When the monitoring control information transmission process ends, a power tide power sale determination process is performed (S130). That is, it is a process for determining whether the power receiving facility 42 is in a power selling state or a non-power selling state by the power flow switching information from the power flow switching unit 11 and the latest control information transmission processing.
If the power receiving facility 42 is in the power selling state, the system monitoring control end process (S133) is performed as it is, but basically, since the system monitoring control is continued, a series of processes are repeated. Become.
When the power receiving facility 42 is in a non-power selling state, a demand peak release determination is performed (S131). That is, it is a determination process that compares the predicted demand value and the target demand value at the time of demand peak release determination. When the demand peak is canceled (no demand peak detected), the power monitoring control information is transmitted from the system monitoring control device 12 to the power flow switch 11 (S132), and the system monitoring control end processing (S133) is performed. When the demand peak is not canceled (demand peak detection), the process returns to the photovoltaic power generation system information reception process (S123).

  Basically, it is preferable to continuously monitor and control the system monitoring control device 12 according to the present invention, but when the predicted demand value is very unlikely to exceed the target demand value (such as at night or in winter). May end the monitoring control of the system monitoring control device 12 (S134).

The system monitoring control device 12 according to the present invention has been described above. In the above example, a solar power generation system is used as an example. However, the system monitoring control device 12 according to the present invention can be applied to a renewable energy system that is a target for purchasing power.
By using this equipment to record the amount of power used in the load facility and calculate / determine the predicted demand value over time, it is not only necessary to sell the total amount of electricity generated by renewable energy to the power utility. It is now possible to keep the demand value of the load equipment below the target demand value by using the electricity generated at a certain time on the load equipment side. This can be expected to reduce annual electricity charges.

DESCRIPTION OF SYMBOLS 1 ... Monitoring control part 11 ... Power flow switching device 12 ... System monitoring control apparatus 122 ... Power flow switching information receiving part 123 ... Solar power generation system information receiving part 124 ... Electric power meter Information receiving unit 125 ... Predicted demand value calculating unit 126 ... Demand peak determining unit 127 ... Control information transmitting unit 13 ... External recording unit

2 ... Solar power generation system

3. Load equipment

4 ... Facilities of electric power company facilities

5 ... Integrated management unit 51 ... Management server 52 ... Management display device

Claims (2)

By switching the electricity generated by the renewable energy power generation system to use in the load facility that is the target of use of the electricity generated by the renewable energy power generation system and selling the power to the power company, the demand in the load facility is changed. A system monitoring and control device whose purpose is to make the value below the target demand value,
The system monitoring and control device is at least
A renewable energy power generation system information receiving unit for receiving power generation information transmitted from the renewable energy power generation system;
A power flow switch information receiving unit for receiving power flow switch information from the power flow switch;
A power meter information receiving unit for receiving load facility power usage information from a power meter that records the power usage status of the load facility;
A predicted demand value calculation unit that calculates a predicted demand value over time using a predetermined demand time limit in the load facility using the load facility power usage information;
A demand peak determining unit for comparing and comparing the predicted demand and the target demand value in the load facility;
A control information transmission unit for transmitting control information for either power sale to a power company or use of load equipment to the power flow switching device according to the demand peak determination result;
A system monitoring and control apparatus comprising:
The predicted demand value calculation unit further includes:
A first demand calculation unit that calculates a demand value per unit time shorter than the demand time period,
A second demand calculation unit that calculates the accumulated demand value at the calculation time by summing up the first demand values from the start time of the demand time period including the calculation time to the calculation time;
A predicted demand is calculated by calculating the amount of power consumption change using the first demand value that is relatively recent from the time of calculation and calculating the demand value from the time of calculation to the end of the demand time period and summing it with the second demand value. A predicted demand calculator for calculating a value,
The system monitoring control apparatus according to claim 1, comprising: