JP2009232668A - Electric power supply system and power supply method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide stable power supply even by using natural energy with respect to an electric power supply system and an electric power supply method, which supply power to a load. <P>SOLUTION: An electric accumulation unit 111 which has one or more cells, a primary charging system which acquires electric power by using natural energy and charges the electric accumulation unit 111 with power, a feeding unit for supplying the power, which the electric accumulation unit 111 stored, to a large fluctuating load 21 and a small fluctuating load 22, and a secondary charging system for charging the electric accumulation unit 111, which has not been charged to a target level in spite of the charge by the first charging system, by using commercial power. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power supply system and a power supply method for supplying power to a load.

  Due to the shortage of fuel resources such as oil and coal, global warming, environmental pollution and other problems, efforts based on the idea of energy conservation are being made worldwide. In this effort, efforts are made to obtain electric power using sunlight, wind power, and further natural energy such as wave power and geothermal heat (see, for example, Patent Document 1).

  In this patent document 1, electric power obtained by solar power generation is stored in two secondary batteries, and by repeating power supply (discharge) and power storage (charge) alternately with these two secondary batteries, It has been proposed to continue supplying power to the load using natural energy.

However, in power generation using natural energy such as sunlight, wind power, and wave power, the amount of power generation depends on the weather conditions, and depending on the weather conditions, the secondary battery may not be able to store electricity at all. In addition, even in power generation using natural energy called geothermal energy, the amount of power generation is also affected by the wide-range weather conditions including the crustal deformation conditions (hereinafter referred to as the wide-range meteorological conditions). May not be able to store electricity at all. Therefore, various attempts to accurately predict the amount of power generation using natural energy have been proposed (see, for example, Patent Document 2).
JP-A-9-121461 JP 2003-32912 A

  However, no matter how accurate the power generation prediction technology using natural energy is, the prediction is prediction, and a deviation from the actual power generation is inevitable, and the power that relies on the prediction of the power generation using natural energy The supply tends to be unstable.

  Moreover, in the approach of obtaining electric power using natural energy, the issue of how to efficiently supply electric power obtained using natural energy to a load is still an important issue.

  In view of the above circumstances, the present invention provides a power supply system and a power supply method capable of performing stable power supply while using natural energy, and efficiently supplies power obtained using natural energy to a load. An object of the present invention is to provide a power supply system that can perform the above-described operation.

A first power supply system of the present invention that solves the above object is a power supply system that supplies power to a load.
An electricity storage unit having one or more cells;
A primary charging system that obtains electric power using natural energy and charges the electric storage unit with the electric power;
A supply unit for supplying the power stored in the power storage unit to the load;
And a secondary charging system that charges a power storage unit that has been charged by the primary charging system but has not been charged to a target level using commercial power to the target level.

  Natural energy here refers to energy such as sunlight, wind power, and even wave power and geothermal heat, and commercial power refers to power supplied from an electric power company, that is, power obtained by purchasing power (hereinafter referred to as power). the same.). The target level may be the full charge level of the power storage unit or less than the full charge level (hereinafter the same).

  Further, the number of the power storage units may be one or a plurality, and even when there are a plurality of the power storage units, they may be connected in parallel and handled as one unit. The primary charging system may charge the power storage unit with electric power obtained using natural energy while the secondary charging system is charging the power storage unit with commercial power. Alternatively, charging to the power storage unit may be stopped while the secondary charging system is charging the power storage unit using commercial power.

  According to the first power supply system of the present invention, the power storage unit is first charged with natural energy in accordance with the meteorological conditions without depending on the prediction of the amount of power generation using natural energy, and the target level is reached. On the other hand, if it is insufficient, it is charged with commercial power. For this reason, in the 1st electric power supply system of this invention, the stable electric power supply can be performed, using natural energy.

  Further, in the first power supply system of the present invention, the secondary charging system charges the power storage unit using the commercial power during a day when the commercial power usage fee is the cheapest. Preferably there is.

  The cheapest time zone here is often a midnight time zone, and in this case, the secondary charging system charges the power storage unit using so-called midnight power.

  Furthermore, in the first power supply system of the present invention, the supply unit is charged in a power storage unit that is being charged by at least one of the primary charging system and the secondary charging system. It is also preferable to supply power to the load.

  By supplying power while charging in this way, the power storage unit can be used efficiently, and is particularly effective when there is only one power storage unit.

A second power supply system of the present invention that solves the above object is a power supply system that supplies power to a load.
A plurality of power storage units having one or a plurality of cells;
A primary charging system for obtaining electric power using natural energy and charging the electric power to the plurality of power storage units;
A supply unit that supplies, to the load, the power stored in the power storage unit that has been charged to a target level among the plurality of power storage units;
The primary charging system charges a power storage unit different from the power storage unit supplying power to the load,
Furthermore, the power supply system includes a secondary charging system that charges a power storage unit that has been charged to the target level despite being charged by the primary charging system to the target level using commercial power. It is characterized by.

  Also according to the second power supply system of the present invention, each of the plurality of power storage units is first charged by natural energy in accordance with weather conditions without depending on the prediction of the amount of power generation using natural energy, and the target Charge the shortage with the commercial power. In addition, in the second power supply system, the power storage unit used for power supply to the load is limited to the power storage unit charged to the target level. For these reasons, even in the second power supply system of the present invention, stable power supply can be performed while using natural energy.

  In the second power supply system of the present invention, when the secondary charging system charges a power storage unit that has not been charged to the target level with commercial power up to the target level, It is preferable that charging is performed using commercial power during a time period when the power usage fee is the cheapest.

  In this way, commercial power can be purchased cheaply.

Further, in the power supply system of the present invention, before supplying the power stored in the power storage unit to the load, weather information of a scheduled supply time zone in which the power is scheduled to be supplied to the load is acquired and the weather information is acquired. From the prediction unit that predicts the required power amount of the load in the scheduled supply time zone,
It is preferable that it is an aspect provided with the level setting part which sets the said target level based on the required electric energy estimated by the said estimation part.

  According to the said aspect, the cost which purchases commercial power can be suppressed, and an energy saving effect is exhibited more. In this aspect, a technique that causes a deviation from the actual prediction is used, but the prediction here is not the amount of power generation but the required power amount. When power obtained using natural energy is supplied in real time, the difference between the predicted power generation amount and the actual power generation amount leads to a serious power supply problem. However, in the power supply system of the present invention, It is not supplied in real time, and since it is a necessary amount of electric power, there is a time margin. For this reason, after starting the power supply from the power storage unit, if the actual required power amount is likely to be larger than the predicted required power amount, the shortage will be supplemented with commercial power to ensure more stable power supply. Can be made.

Further, in supplying power to the load, commercial power may be used as a backup while mainizing the power stored in the power storage unit. For example,
This power supply system supplies power to both a large variable load and a small variable load that fluctuate relatively little within a working time of a day.
There is a specific aspect in which the supply unit supplies power stored in the power storage unit to the large variable load and supplies commercial power to the small variable load.

  Examples of large fluctuation loads here include loads that depend on weather conditions such as air conditioning equipment and ventilation equipment, power that is repeatedly operated and stopped, and examples of small fluctuation loads. Examples include personal computers and control devices. In addition, lighting fixtures correspond to an example of the above-mentioned large fluctuation load under the operation that is used at night and in the daytime when the amount of solar radiation is low and not used during the daytime when the amount of solar radiation is high. This corresponds to an example of the small fluctuation load under the operation to be used. Further, in this specific aspect, the supply unit may supply only the electric power stored in the power storage unit without always supplying commercial power to the large variable load. Commercial power may be supplied. For example, the supply unit first supplies the stored power stored in the power storage unit to the highly variable load, and when the stored power disappears or falls below a predetermined level, Instead, the commercial power may be supplied, or the commercial power may be simultaneously supplied to the large fluctuation load together with the stored power. When supplying the stored power and commercial power at the same time, it is preferable to increase the stored power supply rate higher than the commercial power supply rate, so that the stored power can be used up completely. The ratio may be the same, or conversely, the supply ratio of commercial power may be higher than the supply ratio of stored power. The supply unit may supply only the commercial power without always supplying the stored power to the small variation load, but may supply the stored power also to the small variation load.

  At present, a fixed charge, which is called a basic charge, of the electricity charge for commercial power is determined by contract power (maximum demand power throughout the year). Therefore, in order to reduce the electricity bill, it is conceivable to reduce the amount of contract power in addition to reducing the amount of power used. According to this specific aspect, by supplying the power stored in the power storage unit to the large variable load, it is possible to reduce the amount of contract power as well as the amount of power used while realizing stable power supply. .

  The power supply system of the present invention may further include a mode setting unit that sets the power supply system to a mode according to the season from a plurality of modes having different target levels.

  In summer, the required electric energy is the highest during the season due to the demand for electric power for cooling, and the required electric energy tends to be the lowest during the season, such as spring and autumn. For this reason, even if the mode is set using this tendency, the cost of purchasing commercial power can be suppressed, and the energy saving effect is further exhibited.

A first power supply method of the present invention that solves the above object is a power supply method for supplying power to a load.
A primary charging step of obtaining power using natural energy and charging the power to a power storage unit having one or more cells;
A supply step of supplying the power stored in the power storage unit to the load;
A determination step of determining whether or not the power storage unit charged by the primary charging system is charged to a target level;
A secondary charging step of charging the power storage unit to the target level using commercial power when it is determined that the power storage unit is not charged to the target level by executing the determination step. It is characterized by.

  The first power supply method of the present invention is implemented by the first power supply system of the present invention, and can perform stable power supply while using natural energy.

  Further, in the first power supply method of the present invention, the secondary charging step is a step of charging the power storage unit using the commercial power in a time zone in which the commercial power usage fee is the cheapest within a day. Preferably there is.

  Furthermore, in the first power supply method of the present invention, the supplying step is performed by storing power in a power storage unit that is being charged by at least one of the primary charging system and the secondary charging system. It is also preferable that the power is supplied to the load.

A second power supply method of the present invention that solves the above-described object is a power supply method for supplying power to a load.
A primary charging step of obtaining electric power using natural energy and charging the electric power to a plurality of power storage units having one or more cells;
A supply step of supplying power stored in a power storage unit charged to a target level to the load among the plurality of power storage units;
The primary charging step is a step of charging a power storage unit different from the power storage unit supplying power to the load,
Further, in the power supply method, a determination step of determining whether or not the power storage unit charged by the primary charging system is charged to the target level;
A secondary charging step of charging the power storage unit to the target level using commercial power when it is determined that the power storage unit is not charged to the target level by executing the determination step. It is characterized by.

  The second power supply method of the present invention is implemented by the second power supply system of the present invention, and can perform stable power supply while using natural energy.

  In the second power supply method of the present invention, when the secondary charging step charges the power storage unit that has not been charged to the target level with commercial power to the target level, It is preferable that the charging is performed using commercial power in a time zone in which the power usage fee is the cheapest.

Furthermore, in the power supply method of the present invention, before supplying the power stored in the power storage unit to the load, weather information acquisition for acquiring weather information of a scheduled supply time zone for supplying the power to the load Steps,
From the weather information acquired by executing the weather information acquisition step, a required power amount prediction step of predicting the required power amount of the load in the scheduled supply time zone,
A mode having a level setting step of setting the target level based on the required power amount predicted by executing the required power amount prediction step is also preferable.

  Moreover, you may decide to have the mode setting step which sets to the mode according to a season from the several mode from which the said target level differs.

Furthermore, in the power supply method according to the present invention, the power supply method uses both a large variable load whose power consumption is relatively large and a small variable load which is relatively small within an operating time of one day. A method of supplying power to
It is also preferable that the supplying step is a step of supplying electric power stored in the power storage unit to the large fluctuation load and supplying commercial electric power to the small fluctuation load.

The third power supply system of the present invention that solves the above-mentioned object is
An electricity storage unit having one or more cells;
A primary charging system that obtains electric power using natural energy and charges the electric storage unit with the electric power;
And a supply unit that supplies DC power stored in the power storage unit to a load driven by DC power among the loads.

  Here, the primary charging system may obtain direct current power or obtain alternating current power using natural energy. Moreover, the said primary charging system may have a rectifier which converts the alternating current power obtained using natural energy into direct current power.

  According to the third power supply system of the present invention, conversion from DC power to AC power becomes unnecessary, and conversion loss does not occur. For this reason, in the 3rd electric power supply system of this invention, the electric power obtained using natural energy can be efficiently supplied to a load even a little.

In the third power supply system of the present invention, the primary charging system obtains DC power using natural energy, and charges the DC power to the power storage unit.
The supply unit may supply the DC power to the DC load before charging the power storage unit with DC power obtained by the primary charging system using natural energy.

  Further, in the third power supply system of the present invention, the supply unit supplies the DC power stored in the power storage unit to the DC load, and among the loads, to the AC load driven by AC power, DC power may be converted into AC power and supplied.

  Furthermore, the third power supply system of the present invention further includes a secondary charging system that charges, using commercial power, a power storage unit that is charged to the target level despite being charged by the primary charging system. It is preferable.

  According to the present invention, a power supply system and a power supply method capable of performing stable power supply while using natural energy, and supplying power obtained using natural energy to a load as efficiently as possible. A power supply system is provided.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing a schematic configuration of an embodiment in a power supply system of the present invention.

  The power supply system 1 illustrated in FIG. 1 includes two power storage units 111 and 112, a solar power generation panel 12, a wind power generation unit 13, a natural energy charging circuit 14, and a control unit 15. The two power storage units 111 and 112 are both sodium sulfur batteries (NaS batteries) and have three small cells 1111 and 1121, but the power storage units are not limited to NaS batteries, Moreover, it may consist of one large cell. Hereinafter, when it is necessary to distinguish each of these two power storage units 111 and 112, the power storage unit shown on the left side of FIG. 1 is referred to as the first power storage unit 111, and the power storage unit shown on the right side is the second power storage unit. It will be referred to as 112. The photovoltaic power generation panel 12 directly converts solar light energy into electric energy by the photovoltaic effect to obtain electric power. In addition, the wind power generation unit 13 is for obtaining electric power by turning a generator by wind power. Although these solar power generation panel 12 and the wind power generation unit 13 are comparatively small things which can be installed in a building, they are not limited to a magnitude | size. In addition to the solar power generation panel 12 and the wind power generation unit 13, a wave power generation unit, a geothermal power generation unit, or the like may be used.

  The natural energy charging circuit 14 controls current and voltage. Open / close switches 141 and 142 are provided on paths connecting the natural energy charging circuit 14 and the two power storage units 111 and 112, respectively. The electric power obtained by the solar power generation panel 12 and the wind power generation unit 13 is stored in a desired power storage unit by the control unit 15 turning on / off these open / close switches 141 and 142. Accordingly, the combination of the solar power generation panel 12, the wind power generation unit 13, the natural energy charging circuit 14, the open / close switches 141 and 142, and the control unit 15 corresponds to an example of the primary charging system according to the present invention.

The power supply system 1 shown in FIG. 1 also includes a commercial power charging circuit 16.
Here, in each power storage unit 111, 112, a level of 80% with respect to the full charge level is set as the target level. However, in the power supply system 1 of the present embodiment, power is obtained using natural energy that depends on weather conditions such as sunlight and wind power, and thus the amount of power generation is easily affected by weather conditions. For this reason, in the power supply system 1, the power storage units 111 and 112 are not necessarily charged to the target level with power obtained using natural energy. Therefore, in the power supply system 1 shown in FIG. 1, the storage of electric power obtained using natural energy is performed according to the weather conditions, and purchased from the electric power company as a backup for charging the two power storage units 111 and 112. So-called commercial power is used. At present, commercial power usage charges are the lowest during the midnight hours of the day. In this power supply system 1, when a power storage unit that has been charged using natural energy in the daytime is not charged to the target level, the power storage unit is charged to the target level using commercial power during midnight. To do. The commercial power charging circuit 16 shown in FIG. 1 transforms the power storage units 111 and 112 into a voltage that can be charged, converts an AC voltage into a DC voltage, and further prevents the current storage units 111 and 112 from being overcharged. Control the voltage. Open / close switches 161 and 162 are also provided on paths connecting the commercial power charging circuit 16 and the two power storage units 111 and 112, respectively, and the control unit 15 turns on / off the open / close switches 161 and 162. As a result, midnight power is charged in the desired power storage unit. Therefore, the combination of the commercial power charging circuit 16, the open / close switches 161 and 162, and the control unit 15 corresponds to an example of the secondary charging system according to the present invention.

  The control unit 15 includes a prediction unit 151 and a level setting unit 152, which will be described later.

  Furthermore, the power supply system 1 shown in FIG. 1 also includes a power adjustment circuit 17 and a switchboard 18. The power adjustment circuit 17 converts a DC voltage into an AC voltage and boosts the voltage. Open / close switches 171 and 172 are also provided on the paths connecting the power adjustment circuit 17 and the two power storage units 111 and 112, and the control unit 15 turns the open / close switches 171 and 172 on and off. Two types of power, that is, power adjusted by the power adjustment circuit 17, that is, power stored in the power storage units 111 and 112, and commercial power are transmitted to the switchboard 18. The switchboard 18 supplies power stored in the power storage units 111 and 112 to the large fluctuation load 21 and supplies commercial power to the small fluctuation load 22. That is, when the control unit 15 turns on the open / close switches 171 and 172, the electric power stored in the power storage units 111 and 112 is adjusted by the power adjustment circuit 17 and supplied from the switchboard 18 to the large fluctuation load 21. Therefore, the combination of the power adjustment circuit 17, the open / close switches 171, 172, the switchboard 18 and the control unit 15 corresponds to an example of the supply unit referred to in the present invention. The large fluctuation load 21 is a load in which the power consumption fluctuates relatively greatly within the operation time of one day. Examples of the large variable load 21 include a load whose electric power consumption is influenced by weather conditions such as air conditioning equipment and ventilation equipment, and power that is repeatedly operated and stopped (for example, a lift for lifting a car in an automobile maintenance shop). Etc. On the other hand, the small variation load 22 is a load such as a personal computer or a control device, in which the amount of power used varies relatively little within the operation time of one day. It should be noted that the luminaire is equivalent to the large variable load 21 under the operation that is used at night and in the daytime when the amount of solar radiation is small and not used during the daytime when the amount of solar radiation is large. This corresponds to the small fluctuation load 22 under the continuous operation. At present, a fixed charge, which is called a basic charge, of the electricity charge for commercial power is determined by contract power (maximum demand power throughout the year). Therefore, in order to reduce the electricity bill, it is conceivable to reduce the amount of contract power in addition to reducing the amount of power used. According to the power supply system of the present embodiment, by supplying the power stored in the power storage units 111 and 112 to the large variable load 21, while realizing stable power supply, the amount of contract power as well as the amount of power used. Can also be lowered.

  Note that commercial power may also be supplied to the large fluctuation load 21. For example, when the stored power stored in the power storage units 111 and 112 is first supplied to the large fluctuation load 21 and the stored power disappears or falls below a predetermined level, the large fluctuation load 21 is replaced with the commercial power instead of the stored power. Electric power may be supplied, or commercial power may be simultaneously supplied to the large fluctuation load 21 together with the stored electric power. When supplying stored power and commercial power at the same time, it is preferable to increase the stored power supply ratio higher than the commercial power supply ratio so that the stored power can be used up completely. May be the same, and conversely, the supply rate of commercial power may be higher than the supply rate of stored power.

  Furthermore, initially, the stored power is supplied from the power storage units 111 and 112 to both the large variable load 21 and the small variable load 22, and the power storage level of the power storage units 111 and 112 is lowered to a predetermined lower limit level (including zero level). Then, from that point of time, commercial power may be supplied to both the large variable load 21 and the small variable load 22 or only to the small variable load 22. Similarly, initially, the stored power is supplied to both loads (21, 22), and when the amount of power supply per hour, in other words, the required amount of power per hour exceeds a predetermined value, commercial power is supplied to both loads ( 21, 22) or only the small fluctuation load 22 may be supplied.

  Next, how the power supply system 1 shown in FIG. 1 is operated over several days will be described.

  FIG. 2 is a diagram showing a time schedule of the power supply system shown in FIG. 1 for several days.

  The time schedule shown in FIG. 2 is a schedule for supplying power to an office with business hours from 9:00 am to 6:00 pm. Here, 8:00 am, one hour before the start of business, is set as the time when the large variable load 21 shown in FIG. In addition, the business end is at 6:00 pm, but considering the overtime, 8:00 pm is set as the time when the large variable load 21 finishes operation. As shown in FIG. 2, the electric power stored in the first power storage unit 111 is large for 12 hours from 8:00 am to 8:00 pm on the first day (this 12 hours is referred to as a large variable load operating time zone). It is supplied to the variable load 21. It should be noted that the setting can be changed in this large variable load operating time zone. Then, after the lapse of 24 hours from 8:00 pm, the first time until the midnight time zone (here from 1 am to 4 am) where the usage charge of commercial power is the cheapest has arrived The power storage unit 111 is charged using natural energy such as sunlight and wind power (hereinafter, charging using natural energy is referred to as primary charging). That is, the first power storage unit 111 is primarily charged for 29 hours. Here, primary charging by both sunlight and wind power is possible in the daytime, but primary charging is performed only by wind power at night. Note that, for some reason, the large variable load 21 is before 8:00 am set as the time when the large variable load 21 starts operation or after 8:00 pm when the large variable load 21 ends operation. When is operated, commercial power is supplied.

  Even if the first power storage unit 111 is primarily charged for 29 hours, if it is not charged to a target level corresponding to 80% of the fully charged level, charging using commercial power during the midnight time period ( Hereinafter, charging using commercial power is referred to as secondary charging). If the first power storage unit 111 is charged to the target level by the secondary charging, the secondary charging is terminated, and the first power storage unit 111 is started early in the morning (am 4 o'clock). Thus, according to the electric power supply system of this embodiment, the electrical storage unit charged to the target level is made up. When supplying power obtained using natural energy in real time, the unstable part where the power generation amount fluctuates cannot be used for power supply. By doing so, it is possible to effectively use nearly 100% of the electric power obtained using natural energy, although there is some loss due to natural discharge. Then, after the arrival of 8:00 am, which is the operation start time of the large variable load 21 on that day (third day), electric power is supplied from the first power storage unit 111 to the large variable load 21.

  Note that if secondary charging is performed during the above-mentioned midnight time period, commercial power can be purchased at a low cost. However, the time period during which secondary charging is performed does not necessarily have to be the midnight time period. What is necessary is just to be able to equalize the amount of power purchased. In the example shown in FIG.

  On the other hand, the second power storage unit 112 is primarily charged during a large variable load operating time period in which the first power storage unit 111 supplies power, and the first power storage unit 111 is charged with a large fluctuation. Electric power is supplied during the load operating hours. That is, as shown in FIG. 2, the second power storage unit 112 is primarily charged during the first and third day large fluctuation load operating hours during which the first power storage unit 111 supplies power. In addition, electric power is supplied during the large variable load operating time zone on the second day when the first power storage unit 111 is charged. In the night of the first day and the night of the second day, the first power storage unit 111 and the second power storage unit 112 are simultaneously primary charged at the same time (from 8:00 pm to 1:00 am on the next day). However, in this time zone, the controller 15 shown in FIG. 1 turns on the two open / close switches 141 and 142 so that the two power storage units 111 and 112 are simultaneously primary charged. The In the example shown in FIG. 2, even when the second power storage unit 112 is primarily charged for 29 hours, it is not charged to the target level but is charged to the target level by secondary charging.

  As described above, in the power supply system 1 of the present embodiment, a plurality of power storage units are prepared, and the timing of power supply (discharge) and power storage (charge) is not overlapped in one power storage unit. If it sees, the electrical storage to an electrical storage unit and the electric power supply from an electrical storage unit will be performed simultaneously. In addition, the storage of electric power obtained using natural energy is performed within the time allowed by the succession of weather conditions, and the shortage with respect to the target level is compensated by charging with midnight electric power. For this reason, the power storage unit is charged to the target level by the time when the load starts operation, and the minimum required power storage amount is secured. Therefore, in the power supply system of the present embodiment, stable power supply can be performed while using natural energy.

  Next, a power supply method by the power supply system 1 shown in FIG. 1 will be described.

  FIG. 3 is a flowchart showing a method of charging the first power storage unit by the power supply system shown in FIG. 1 and supplying power from the first power storage unit.

  The power supply method described here is a power supply method according to the time chart shown in FIG. 2, and the time chart is stored in the control unit 15 shown in FIG. 1.

  The control unit 15 shown in FIG. 1 has a clocking function, and when the time when the large variable load 21 finishes operating (8 pm on the first day shown in FIG. 2) arrives, The open / close switch 141 provided in the path connecting the energy charging circuit 14 and the first power storage unit 111 is turned on, and the first power storage unit 111 starts primary charging (step S1_1). The controller 15 determines whether or not 29 hours have elapsed since the start of primary charging (step S1_2), and maintains the open / close switch 141 in an on state until 29 hours have elapsed. By doing so, the first power storage unit 111 is primarily charged for 29 hours. Although not shown in FIG. 1, in the power supply system 1, when the first power storage unit 111 is charged to the full charge level due to a large amount of sunlight irradiation or strong wind, Electric power obtained by the photovoltaic power generation panel 12 and the wind power generation unit 13 is configured to be charged to the second power storage unit 112 through the first power storage unit 111. When 29 hours have elapsed since the start of the primary charging, the control unit 15 switches the open / close switch 141 in the on state to the off state, and the primary charging to the first power storage unit 111 ends ( Step S1_3). The time when the primary charging ends in this way is 1:00 am, which is the start time of the midnight time zone in which the commercial power usage fee is the cheapest in the day. These steps S1_1 to S1_3 correspond to an example of the primary charging step according to the present invention.

  Next, the prediction part 151 provided in the control part 15 shown in FIG. 1 performs a weather information acquisition step. That is, the prediction unit 151 acquires weather information from 8:00 am to 8:00 pm that day, which is the latest as of 1:00 am, through a communication line such as the Internet (step S1_4). Here, during the time period from 8:00 am to 8:00 pm on the day when the weather information is acquired, the supply schedule is scheduled to supply power to the large variable load 21 from the first power storage unit 111 that has been primarily charged so far. Corresponds to the time zone. Subsequently, the prediction unit 151 executes a necessary power amount prediction step (step S1_5) for predicting the necessary power amount necessary for operating the large variable load 21 in the scheduled supply time period from the acquired weather information. . That is, the prediction unit 151 obtains the outside temperature, the amount of solar radiation, and the like in the scheduled supply time period from the acquired weather information, and from the outside temperature, the amount of solar radiation, etc., how much the large variable load 21 operates and how much power. Calculate how much is needed. In addition, the difference of the required electric energy calculated here depending on the day depends on the day of the required electric energy for the load of the air conditioning equipment or the ventilation equipment, etc. in which the electric power consumption is influenced by the weather condition in the large fluctuation load 21. This is due to the difference. When the prediction unit 151 finishes the prediction of the required power amount in step S1_5, the level setting unit 152 provided in the control unit 15 now selects the target of the first power storage unit 111 based on the predicted required power amount. A level setting step (step S1_6) for setting the level is executed. The target level is a charge level of the first power storage unit 111 that can supplement all of the necessary power predicted in step S1_5, and priority is given to using up the power stored in the first power storage unit 111. The level may be set to be the same as or slightly lower than the required power predicted in step S1_5, but may be set slightly higher in some cases. Here, the target level is set to 80% of the fully charged level of the first power storage unit 111. If the acquired weather information shows that the outside temperature is very high and the amount of solar radiation is very large, the target level may be 90% or more of the full charge level. If the amount of solar radiation is very low, the target level may be 70% or less.

  When the target level is set, the control unit 15 executes a determination step (step S1_7) for determining whether or not the first power storage unit 111 that has been primarily charged up to now is charged to the target level. . If the first power storage unit 111 is not charged to the target level, the control unit 15 turns on the open / close switch 161 provided on the path connecting the commercial power charging circuit 16 and the first power storage unit 111, and This time, secondary charging is started for one power storage unit 111 (step S1_8). Thereafter, the control unit 15 periodically determines whether the first power storage unit 111 has been charged to the target level (step S1_9), and the open / close switch 161 until the first power storage unit 111 is charged to the target level. Is kept on. By doing so, the first power storage unit 111 continues to be secondary charged. When the first power storage unit 111 is secondarily charged to the target level in this way, the control unit 15 switches the open / close switch 161 in the on state to the off state, and the second charging to the first power storage unit 111 is completed. (Step S1_10). These steps S1_8 to S1_10 correspond to an example of the secondary charging step according to the present invention. At the latest, the secondary charging ends at 4 am, which is the end time of the midnight time zone in which the commercial power usage fee is the cheapest in the day. The storage capacities of both the first and second power storage units 111 and 112 are capacities that are completely charged by secondary charging even if the first power storage unit 111 is not charged at all by primary charging. As described above, by using the weather information in the power supply scheduled time zone, it is possible to reduce the cost of purchasing commercial power, and the energy saving effect is further exhibited.

  Subsequently, the control unit 15 determines whether or not the time (8 am on the third day shown in FIG. 2) when the large variable load 21 starts operation has been reached using the time measuring function (step S1_11). The power supply system 1 is in a standby state until 8 am arrives. If it is determined in step S1_7 that the first power storage unit 111 is charged to the target level, step S1_11 is executed without performing secondary charging.

  When 8:00 am arrives, the control unit 15 turns on the open / close switch 171 provided in the path connecting the power adjustment circuit 17 and the first power storage unit 111, and starts the large fluctuation load 21 from the first power storage unit 111. The power supply to is started (step S1_12). This time, the control unit 15 determines whether or not the time (8 pm on the third day shown in FIG. 2) when the large variable load 21 finishes operation has arrived using the time measuring function (step S1_13). Until 8:00 p.m. arrives, power continues to be supplied from the first power storage unit 111 to the catastrophic load 21. When 8:00 p.m. arrives, the control unit 15 switches the open / close switch 171 in the on state to the off state, and the power supply from the first power storage unit 111 to the large variable load 21 ends (step S1_14). Returning to step S1_1, primary charging of the first power storage unit 111 is started again. These steps S1_12 to S1_14 correspond to an example of the supplying step according to the present invention.

  Although there are two power storage units, three or more power storage units may be used. Even if there are three or more energy storage units, the primary charge is performed by charging one energy storage unit to the full charge level and then shifting to the next energy storage unit. The more the capacity is increased, the more the power storage units are primary charged during one primary charge depending on the weather conditions. The stored power storage unit can be preferably used as a power storage unit as stock. In addition, if the number of power storage units is increased and the charging capacity per time of secondary charging is increased to simultaneously perform secondary charging to a plurality of power storage units, and the supply amount of commercial power is further increased to some extent, the power supply system of the present invention Can also be applied to loads operating continuously for 24 hours.

  Also, in this explanation, the target level is set after the arrival of the start time of the midnight time zone when the commercial power usage fee is the cheapest in the day, but at a time earlier than that time. Also good. However, it is generally preferable to set the target level at a time as close as possible to the scheduled supply time period because the accuracy of weather information generally increases.

  In addition, during the primary charging, the control unit 15 monitors the charge level of the first power storage unit 111. When the first power storage unit 111 is charged to the full charge level, the control unit 15 is turned on at that time. The on / off switch 141 in the state may be switched to the off state, and the primary charging may be stopped. Furthermore, the other on / off switch 142 that has been in the off state until now, that is, the natural energy charging circuit 14 The opening / closing switch 142 provided in the path connecting the second power storage unit 112 may be turned on to start primary charging of the second power storage unit 112. Further, the second power storage unit 112 may be sold instead of being primarily charged.

  Next, a second embodiment of the power supply system of the present invention will be described. In the power supply system of the second embodiment, mode setting is used without using weather information. In the following description, the same components as those described so far are denoted by the same reference numerals, and the description will focus on matters specific to the second embodiment.

  The configuration of the power supply system of the second embodiment is the same as the configuration of the power supply system shown in FIG. 1 except for the control unit, and the detailed configuration other than the control unit will not be described.

  FIG. 4 is a diagram illustrating a configuration of a control unit in the power supply system of the second embodiment.

  The control unit 15 ′ illustrated in FIG. 4 includes a mode table 153 and a mode setting unit 154. In the mode table 153, three modes having different target levels as charging targets for the two power storage units 111 and 112 are prepared. This target level is determined as follows. First, when the outside air temperature becomes considerably high, the required power amount (maximum power amount) supplied by the power supply system is calculated in order to keep the room temperature at a desired temperature, and the calculated maximum power amount is set to 100%. To do. For example, when the outside air temperature reaches 35.5 ° C., the maximum amount of electric power required to keep the room temperature at 28 ° C. is calculated, and the maximum electric energy is set to 100%. The power storage capacities of the two power storage units 111 and 112 are equal to or greater than the maximum power amount, and even if the first power storage unit 111 is not charged at all by primary charging, it is fully charged by secondary charging. Capacity. The target level is determined by what percentage each of the two power storage units 111 and 112 is charged with respect to the maximum electric energy. As shown in FIG. 4, the mode has three season modes: a summer mode, a winter mode, and a spring / autumn mode. The summer mode is a mode in which the target level is set to 80% from June 15 to September 14, and the winter mode is set to 60% from December 15 to March 14. This is the determined mode. The spring / autumn mode is a mode in which the target level is set to 50% from March 15 to June 14 and from September 15 to December 14. The mode setting unit 154 counts the date by the time measuring function, and sets the power supply system to a mode according to the season from among these three modes.

  FIG. 5 is a flowchart showing a method of charging the first power storage unit and supplying power from the first power storage unit by the power supply system of the second embodiment.

  In the flowchart shown in FIG. 5, instead of the three steps of step S1_4 for acquiring the weather information shown in FIG. 3, step S1_5 for predicting the required electric energy from the acquired weather information, and step S1_6 for setting the target level. A mode setting step (step S2_1) for setting the mode is provided. That is, the mode setting unit 154 provided in the control unit 15 ′ shown in FIG. 4 before the primary charging of the first power storage unit 111 is started in the same manner as in step S1_1 shown in FIG. 3 (step S2_2) The mode corresponding to the current date is selected from the three modes prepared in the mode table 153, and the power supply system is set to the selected mode (step S2_1). By doing so, the power supply system of the second embodiment is set to a mode according to the season, and the target level is 80% of the maximum power amount from June 15 to September 14. From December 15th to March 14th, it will be 60% of the maximum power, and from March 15th to June 14th and from September 15th to December 14th 50% of the maximum power amount.

  Each step after step S2_3 shown in FIG. 5 is the same as each of step S1_2, step S1_3, and steps S1_7 to S1_14 shown in FIG. 3, so that the description thereof is omitted here. Even in the power supply system, stable power supply can be performed while using natural energy. Also, with this power supply system, the cost for purchasing commercial power can be reduced by setting the mode according to the season, and the energy saving effect is further exhibited.

  In addition, while performing the mode setting as described above, the weather information is acquired as described with reference to FIG. 3, the required power amount is predicted from the weather information, and the target level determined by the mode is set to the required power. You may make it correct based on quantity.

  In addition, the target level is fixed throughout the year (for example, the full charge level of the power storage unit is always set) instead of setting the target level by predicting the required power amount from weather information or using the target level determined by the mode. It may be fixed as a target level).

  Then, 3rd Embodiment of the electric power supply system of this invention is described. In the power supply system of the third embodiment, power is continuously supplied for 24 hours using one power storage unit. The power supply system of the third embodiment can be realized by changing the operation of the power supply system of the first embodiment shown in FIG. In the following, with reference to FIG. 1, the same components as those described so far are denoted by the same reference numerals, and description will be made focusing on matters specific to the third embodiment.

  In the power supply system 1 of the third embodiment, only the first power storage unit 111 is used among the two power storage units 111 and 112. For this reason, each open / close switch 142, 162, 172 provided in the path connected to the second power storage unit 112 is always in an off state. The control unit 15 turns on / off the respective open / close switches 141, 161, 171 provided on the path connected to the first power storage unit 111.

  FIG. 6 is a diagram showing a time schedule of the power supply system of the third embodiment for several days.

  The time schedule shown in FIG. 6 is a schedule for continuously supplying power to a 24-hour shop or a 24-hour factory. As shown in FIG. 6, power supply from the first power storage unit 111 is performed continuously for 24 hours. Further, primary charging, which is charging using natural energy, is also continuously performed. That is, wind power generation is performed for 24 hours, and solar power generation is performed only during the time zone in which sunlight is irradiated (time zone centered on daytime). The first power storage unit 111 is continuously charged for 24 hours by such primary charging while continuing to supply power for 24 hours. The control unit 15 in the present embodiment performs the same process as the process of step S1_7 illustrated in FIG. 3 at 1:00 am, which is the start of the midnight time zone in which the commercial power usage fee is the cheapest in the day. That is, it is determined whether or not the first power storage unit 111 that has been primarily charged up to now is charged to the target level. If the first power storage unit 111 is not charged to the target level, the control unit 15 3, the open / close switch 161 provided in the path connecting the commercial power charging circuit 16 and the first power storage unit 111 is turned on in the same manner as the process of step S1_8 shown in FIG. This time, secondary charging is started. The first power storage unit 111 is charged by wind power generation at midnight, but continues to supply power. For this reason, the control unit 15 periodically monitors whether the charge level (power storage level) of the first power storage unit 111 is below the target level, and when the charge level exceeds the target level, the open / close switch 161 To turn off the secondary charging. On the other hand, while the charge level of the first power storage unit 111 is below the target level, the control unit 15 maintains the open / close switch 161 in the on state and continues secondary charging. Moreover, even if the charge level of the 1st electrical storage unit 111 reaches a target level once, if the charge level falls below a target level again, the control part 15 will restart secondary charge.

  In addition, when the wind power generation unit 13 is removed and the primary charging depends only on the solar power generation, the primary charging is performed only in the time zone centering on the daytime, and is necessary in the midnight time zone. Accordingly, only secondary charging is performed.

  Then, 4th Embodiment in the electric power supply system of this invention is described. In the following description, differences from the power supply system of the first embodiment shown in FIG. 1 will be mainly described, and a description overlapping with the power supply system of the first embodiment will be omitted. Further, the same constituent elements as those described so far will be described using the same reference numerals as those used so far.

  FIG. 7 is a diagram showing a schematic configuration of the fourth embodiment in the power supply system of the present invention.

  The power supply system 1 ′ shown in FIG. 7 supplies power to two types of loads. The power supply system 1 ′ is connected to an AC load 25 that is driven by AC power and a DC load 26 that is driven by DC power. Examples of the AC load 25 include the above-described air-conditioning equipment, ventilation equipment, lifts, personal computers, and general household electric appliances such as fluorescent lamps. Since commercial power supplied via a transmission line is AC power, many electric products in the world based on the premise of being driven by this commercial power are AC loads. On the other hand, examples of the DC load 26 include a light emitting diode (LED), a high-intensity discharge lamp (HID), a display device using organic electroluminescence, an audio (speaker, etc.), and the like.

  The photovoltaic power generation panel 12 directly converts solar light energy into electrical energy by the photovoltaic effect to obtain direct current power. Moreover, the wind power generation unit 13 rotates a generator with wind power to obtain AC power. Although not shown in FIG. 1, the wind power generation unit 13 is provided with a rectifier 131. AC power obtained by turning the generator is converted into DC power by the rectifier 131. Therefore, the power output from the solar power generation panel 12 and the wind power generation unit 13 is DC power. Each of the two power storage units 111 and 112 stores DC power.

  In addition, an AC switchboard 181 is provided in the power supply system 1 ′ illustrated in FIG. 7. The DC power stored in the power storage units 111 and 112 is converted into AC power by the power adjustment circuit 17 and the voltage is boosted and supplied to the AC load 25 by the AC switchboard 181.

  Further, the power supply system 1 ′ is provided with a DC switchboard 182 that supplies DC power to the DC load 26 and a voltage adjustment circuit 192 that boosts the voltage of the DC power. In addition, an open / close switch 145 for power storage is provided on a path connecting the solar power generation panel 12 and the wind power generation unit 13 and the natural energy charging circuit 14. In addition, an open / close switch 191 for direct current power transmission is provided on a path branched from the path and connected to the voltage adjustment circuit 192. Further, a discharge open / close switch 175 is provided on a path connecting the two power storage units 111 and 112 and the voltage adjustment circuit 192. The controller 15 turns on / off these open / close switches 145, 191 and 175.

  When the control unit 15 turns on the open / close switch 175 for discharging, the DC power stored in the power storage units 111 and 112 is boosted by the voltage adjustment circuit 192 and transmitted to the DC switchboard 182 as DC. The DC switchboard 182 supplies the DC power that has been transmitted to the DC load 25. Therefore, the combination of the voltage adjustment circuit 192, the open / close switch 175, the DC switchboard 182 and the control unit 15 corresponds to an example of the supply unit in the third power supply system of the present invention. When power is supplied to the DC load 25 in this way, conversion from AC power to DC power becomes unnecessary and conversion loss does not occur. Therefore, according to the power supply system 1 ′ of the fourth embodiment, the power obtained by using natural energy can be efficiently supplied to the DC load 26 even a little.

  Further, the DC power output from the solar power generation panel 12 or the wind power generation unit 13 is generated when the control unit 15 turns off the power storage on / off switch 145 and turns on the DC power transmission on / off switch 191. The power is transmitted to the DC switchboard 182 via 192 and supplied to the DC load 25. Again, conversion from AC power to DC power is no longer necessary, conversion loss does not occur, and power obtained using natural energy can be efficiently supplied to the DC load 26 as little as possible.

  On the contrary, when the controller 15 turns on the open / close switch 145 for power storage and turns off the open / close switch 191 for direct current power transmission, the DC power output from the solar power generation panel 12 and the wind power generation unit 13 is natural energy. The charging circuit 14 stores the direct current power in the power storage unit 111.

  In addition, when the power generation amount of the solar power generation panel 12 or the wind power generation unit 13 is large or the like, the control unit 15 turns on both the open / close switch 145 for power storage and the open / close switch 191 for direct current power transmission. The DC power output from the power generation panel 12 and the wind power generation unit 13 is supplied to the DC load 25 and also stored in the power storage unit 111.

  Further, in the power supply system 1 ′ shown in FIG. 7, when the control unit 15 turns on the opening / closing switch 175 for discharge and simultaneously turns on the opening / closing switches 171, 172, the electricity is stored in the power storage units 111, 112. The DC power is supplied to the DC load 26 and is also converted to AC power by the power adjustment circuit 17 and then supplied to the AC load 25.

  Furthermore, also in this power supply system 1 ′, assuming that each power storage unit 111, 112 is not charged to a predetermined target level by DC power obtained using natural energy, two power storage units A commercial power charging circuit 16 is provided to use commercial power as a backup for charging to 111 and 112.

It is a figure which shows schematic structure of one Embodiment in the electric power supply system of this invention. It is a figure which shows the time schedule of the electric power supply system shown in FIG. 1 in several days. It is a flowchart which shows the method of charging a 1st electrical storage unit with the electric power supply system shown in FIG. 1, and supplying electric power from the 1st electrical storage unit. It is a figure which shows the structure of the control part in the electric power supply system of 2nd Embodiment. It is a flowchart which shows the method of charging a 1st electrical storage unit with the power supply system of 2nd Embodiment, and supplying electric power from the 1st electrical storage unit. It is a figure which shows the time schedule of the power supply system of 3rd Embodiment in several days. It is a figure which shows schematic structure of 4th Embodiment in the electric power supply system of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric power supply system 111,112 Power storage unit 1111,1121 Cell 12 Solar power generation panel 13 Wind power generation unit 14 Natural energy charging circuit 141,142 Open / close switch 15 Control part 151 Prediction part 152 Level setting part 153 Mode table 154 Mode setting part 16 Commercial power charging circuit 161, 162 Open / close switch 17 Power adjustment circuit 171, 172 Open / close switch 18 Switchboard 21 Large variable load 22 Small variable load 25 AC load 26 DC load 145 Storage switch 175 Discharge open / close switch 182 DC switchboard 191 Open / close switch for DC power transmission 192 Voltage adjustment circuit

Claims (18)

In a power supply system that supplies power to a load,
An electricity storage unit having one or more cells;
A primary charging system for obtaining electric power using natural energy and charging the electric storage unit with the electric power;
A supply unit for supplying the power stored in the power storage unit to the load;
A power supply system comprising: a secondary charging system that uses commercial power to charge a power storage unit that has been charged by the primary charging system but has not been charged to a target level.   2. The power supply according to claim 1, wherein the secondary charging system is configured to charge the power storage unit using the commercial power in a time zone in which the usage charge of the commercial power is the cheapest in one day. system.   The supply unit supplies power stored in a power storage unit being charged by at least one of the primary charging system and the secondary charging system to the load. The power supply system according to claim 1, wherein: In a power supply system that supplies power to a load,
A plurality of power storage units having one or a plurality of cells;
A primary charging system for obtaining electric power using natural energy and charging the electric power to the plurality of power storage units;
A supply unit that supplies, to the load, the power stored in the power storage unit that has been charged to a target level among the plurality of power storage units;
The primary charging system charges a power storage unit different from the power storage unit supplying power to the load,
The power supply system further includes a secondary charging system that charges the power storage unit that has been charged by the primary charging system but has not been charged to the target level using commercial power to the target level. Power supply system characterized by Before supplying the electric power stored in the electric storage unit to the load, the weather information of the scheduled supply time zone scheduled to supply the electric power to the load is acquired, and the load in the scheduled supply time zone is obtained from the weather information A prediction unit for predicting the required power amount of
The power supply system according to claim 1, further comprising: a level setting unit that sets the target level based on the required power amount predicted by the prediction unit.   5. The power supply system according to claim 1, further comprising a mode setting unit configured to set the power supply system to a mode according to a season from a plurality of modes having different target levels. This power supply system supplies power to both a large variable load and a small variable load that fluctuate relatively little within a working time of a day.
5. The power supply system according to claim 1, wherein the supply unit supplies power stored in the power storage unit to the large variable load and supplies commercial power to the small variable load. 6. . In a power supply method for supplying power to a load,
A primary charging step of obtaining power using natural energy and charging the power to a power storage unit having one or more cells;
Supplying a power stored in the power storage unit to the load;
A determination step of determining whether or not the power storage unit charged by the primary charging system is charged to a target level;
And a secondary charging step of charging the power storage unit with commercial power when it is determined that the power storage unit is not charged to the target level by executing the determination step. Power supply method.   9. The power supply according to claim 8, wherein the secondary charging step is a step of charging the power storage unit using the commercial power in a time zone in which the usage charge of the commercial power is the cheapest within a day. Method.   The supplying step is a step of supplying electric power stored in a power storage unit being charged by at least one of the primary charging system and the secondary charging system to the load. The power supply method according to claim 8, wherein: In a power supply method for supplying power to a load,
A primary charging step of obtaining power using natural energy and charging the power to a plurality of power storage units having one or a plurality of cells;
A supply step of supplying, to the load, the power stored in the power storage unit charged to a target level among the plurality of power storage units;
The primary charging step is a step of charging a power storage unit different from the power storage unit supplying power to the load;
Further, in the power supply method, a determination step of determining whether or not the power storage unit charged by the primary charging system is charged to the target level;
A secondary charging step of charging the power storage unit to the target level using commercial power when it is determined that the power storage unit is not charged to the target level by executing the determination step. A power supply method characterized by the above. A weather information acquisition step of acquiring weather information of a scheduled supply time zone scheduled to supply the power to the load before supplying the power stored in the power storage unit to the load;
From the weather information acquired by executing the weather information acquisition step, a required power amount prediction step of predicting the required power amount of the load in the scheduled supply time zone,
The power supply method according to claim 8, further comprising a level setting step of setting the target level based on a required power amount predicted by executing the required power amount prediction step.   12. The power supply method according to claim 8, further comprising a mode setting step of setting a mode according to a season from a plurality of modes having different target levels. This power supply method is a method of supplying power to both a large-variable load and a small-variable load that fluctuate relatively little within a working time of a day.
12. The power supply method according to claim 8, wherein the supplying step is a step of supplying electric power stored in the power storage unit to the large variable load and supplying commercial power to the small variable load. . An electricity storage unit having one or more cells;
A primary charging system for obtaining electric power using natural energy and charging the electric storage unit with the electric power;
A power supply system comprising: a supply unit configured to supply DC power stored in the power storage unit to a load driven by DC power among the loads. The primary charging system obtains DC power using natural energy, and charges the power storage unit with the DC power.
The said supply part supplies this DC power to the said DC load, before charging the said electrical storage unit with the DC power obtained by the said primary charging system using natural energy. 15. The power supply system according to 15.   The supply unit supplies the DC power stored in the power storage unit to the DC load, and converts the DC power into AC power to be supplied to the AC load driven by AC power among the loads. The power supply system according to claim 15, wherein the power supply system is provided.   16. The power supply system according to claim 15, further comprising a secondary charging system that uses commercial power to charge a power storage unit that has been charged by the primary charging system but has not been charged to a target level. .

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