WO2013145178A1

WO2013145178A1 - Power supply system

Info

Publication number: WO2013145178A1
Application number: PCT/JP2012/058222
Authority: WO
Inventors: 俊介飯田; 岡田　茂
Original assignee: 三洋電機株式会社
Priority date: 2012-03-28
Filing date: 2012-03-28
Publication date: 2013-10-03

Abstract

[Problem] To provide a power supply system that, when the rates for selling electricity become cheaper than the rates for purchasing electricity, can purchase electricity at a cheaper rate than purchasing electricity from the commercial power grid when purchasing electricity, and can sell electricity at a higher rate than selling electricity to the commercial power grid when selling electricity. [Solution] The present invention is characterized by: being provided with a power quantity detection circuit that, for each consumer (2a-2c), detects a first power quantity, which indicates the quantity of power supplied to the plurality of consumers (2a-2c), and a second power quantity, which indicates the quantity of excess power collected from the consumers (2a-2c); setting the unit price for the electricity rate for the first power quantity and the unit price for the electricity rate for the second power quantity to values between the unit price for the rates for purchasing electricity from and the unit price for the rates for selling electricity to the commercial power grid (3); and being configured in a manner so that it is possible to notify each consumer (2a-2c) of the first power quantity and the electricity rate for the first power quantity calculated on the basis of the unit price for the electricity rate of the first power quantity, and the second power quantity and the electricity rate for the second power quantity calculated on the basis of the unit price for the electricity rate of the second power quantity.

Description

Power supply system

The present invention relates to a power supply system that collects surplus power that is not consumed by a plurality of consumers each having a power generation device and supplies the surplus power to a consumer that requests power.

In recent years, power generation devices using renewable energy such as solar cells have been rapidly spreading to consumers. If this spread proceeds rapidly, the power generation cost by renewable energy will be reduced according to the spread. When the generation cost of renewable energy becomes cheaper, the electric power company generates the electric power generated by the renewable energy at each consumer rather than the price of electricity purchased by the customer from the electric power company (commercial power grid) It is expected that the price for selling to (power selling fee) will be cheaper.

If the power selling fee is cheaper than the power purchasing fee, the cost can be reduced if the generated power is consumed by the load in the consumer rather than selling it to the power company. This is because it is necessary to buy back the sold power at a higher price than the sold price. However, the load of the consumer cannot always consume the generated power, and the generated power that has not been consumed is sold as surplus power to the power company.

By the way, Patent Document 1 collects surplus power that is not consumed by a consumer from a plurality of consumers each having a power generation device by using a power storage device that is common to the plurality of consumers, and surpluses to the consumer requesting power. A power supply system for supplying power is disclosed. Even if the electricity sales fee is cheaper than the electricity purchase fee, using such a power supply system, each consumer can store surplus electricity in a common electricity storage device and later reuse the cheap electricity. We were able to.
JP 2011-135651 A

However, when the power supply system of Patent Document 1 is used, if there is not enough power, the power must be purchased from the commercial power system and returned to the power storage device. There was a problem that would buy.

The present invention is an invention made in view of the above-mentioned problem, and when the power selling fee is cheaper than the power purchasing fee, the fee is lower than the power purchased from the commercial power system when purchasing power. An electric power supply system that can be purchased at a higher price than when selling power to a commercial power system is provided.

In order to achieve the above object, demand is collected from a plurality of consumers each having a power generation device, collecting surplus power that is not consumed by the consumer, supplying the surplus power to the consumer requesting power, and requesting the power In a power supply system that obtains power from a commercial power grid when there is a shortage of power to be supplied to a house, the unit price of the power purchase price for purchasing power from the commercial power grid and the power selling price for selling power to the commercial power grid Electric power for detecting for each consumer an input circuit for inputting a unit price, a first electric energy indicating the amount of electric power supplied to the consumer, and a second electric energy indicating the amount of surplus power collected from the consumer. An amount detection circuit, and sets the unit price of the electricity charge for the first amount of electricity and the unit price of the electricity charge for the second amount of electricity to a value between the unit price of the power purchase fee and the unit price of the power sale fee. , The first electric energy and the The second electric power calculated based on the electric charge of the first electric energy calculated based on the unit price of the electric charge of one electric energy, and the unit price of the electric charge of the second electric energy and the second electric energy. It is characterized by being configured to be able to notify each customer of the amount of electricity bill.

According to the present invention, the actual power purchase fee (unit price of the first electricity amount) and the actual power sale fee (first electricity amount electricity) between a plurality of consumers supplied with power by the power supply system. The unit price of the charge) is determined between the unit price of the commercial power grid purchase price and the unit price of the power sale charge. And it is comprised so that the electricity bill of 1st electric energy and the electricity bill of 2nd electric energy can be notified to each consumer. As a result, when the power selling fee is cheaper than the power purchasing fee, each customer can purchase power at a lower price than the power purchased from the commercial power system. In the case of electricity, it can be sold at a higher charge than selling to the commercial power system.

Moreover, in the above-mentioned invention, when electric power is supplied from the commercial power system to the consumer, the unit price of the electricity charge of the first electric energy is increased.

Moreover, in the above-mentioned invention, when electric power is supplied from the commercial power system to the consumer, the consumer is notified that the unit price of the electricity charge of the first power amount has increased. .

Moreover, in the above-mentioned invention, when the surplus power collected from the plurality of consumers cannot be consumed in the plurality of consumers, the surplus power is sold to a commercial power system, and the second power amount at this time It is characterized by lowering the unit price of electricity charges.

Moreover, in the above-mentioned invention, when selling the surplus power to a commercial power system, the customer is informed that the unit price of the electricity charge of the second power amount is lowered.

According to the present invention, when the power selling fee is cheaper than the power purchasing fee, the power can be purchased at a lower fee than the power purchased from the commercial power system. Provides a power supply system that can sell power at a higher rate than selling power to a commercial power system.

It is a schematic diagram which shows the Example of the installation state of an electric power supply system. FIG. 3 is a diagram illustrating a control flowchart of the power storage device 12. It is the schematic of a display monitor.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing an installation state of the power supply system 1. As shown in this figure, a common power supply system 1 is arranged for a plurality of demands 2a to 2c.

The power supply system 1 includes a power storage device 12, a control circuit 13, a current sensor 14, current sensors 15a to 15c, distribution wirings La to Lc, and commercial wiring L. The commercial wiring L is connected to the commercial power system, and the distribution wirings La to Lc branch from the commercial wiring L. The branch wirings La to Lc are connected to the consumers 2a to 2c, respectively. The power supply system 1 uses the branch wirings La to Lc to collect surplus power that is not consumed by a plurality of consumers 2a to 2c and supplies the collected surplus power to the consumers 2a to 2c that request power. To do.

Each consumer 2a to 2c has solar cells 21a to 21c (power generation devices), distribution boards 22a to 22c, power conditioners 23a to 23c, display monitors 24a to 24c, and a load 25, respectively.

The solar cells 21a to 21c are connected to the input sides of the power conditioners 23a to 23c, respectively, and the DC power generated by the solar cells 21a to 21c is converted into AC power in the power conditioners 23a to 23c. The output sides of the power conditioners 23a to 23c are connected to one of the distribution boards 22a to 22c, and the converted AC power is input to one side of the distribution board. The other of the distribution boards 22a to 22c is connected to the distribution lines La to Lc, and the power supplied from the power supply system 1 is input.

The power input from the power conditioners 23a to 23b to the distribution boards 22a to 22c and the power input from the power supply system 1 to the distribution boards 22a to 22c are superimposed in the distribution boards 22a to 22c. The load 25 in each consumer 2a to 2c is used. At this time, if the generated power of the solar cells 21a to 21c is larger than the power consumed by the loads in the consumers 2a to 2c, the surplus power passes through the distribution wirings La to Lc to store other consumers and It is supplied to the device 12 or the commercial power system 3.

The power storage device 12 incorporates a charge / discharge circuit (not shown), and the charge / discharge of the power storage device 12 is controlled using this charge / discharge circuit. The power storage device 12 is connected to the commercial wiring L on the commercial power system side from the connection point A of the distribution wirings La to Lc.

The power storage device 12 included in the power supply system 1 is used to absorb the difference between the plurality of consumers 2a to 2c when the power demand and supply are not equal. Specifically, the power storage device 12 charges the surplus power of the consumers 2a to 2c so that a reverse power flow does not occur in the commercial power grid 3 when the power supply is larger among the plurality of consumers 2a to 2c. To do. Conversely, the power storage device 12 stores power from the commercial power system 3 to the consumers 2a to 2c so that no tidal current occurs from the commercial power system 3 to the consumers 2a to 2c when the demand for power among the plurality of consumers 2a to 2c is greater. Electric power (surplus power collected from each customer) is discharged. The charge / discharge control of the power storage device 12 will be described in detail later.

The current sensor 14 is disposed closer to the commercial power system than the connection point B between the power storage device 12 and the commercial wiring L, and detects the current I at this position. Here, the state in which power is supplied from the commercial power system 3 to the consumers 2a to 2c is assumed to be positive (current I> 0), and the power is flowing backward from the consumers 2a to 2c to the commercial power system 3 Is negative (current I <0).

Current sensors 15a to 15c are arranged on the branch lines La to Lc, respectively, and detect currents Ia to Ic flowing in the branch lines La to Lc. Here, the current supplied from the power supply system 1 to the consumers 2a to 2c is positive (current Ia to Ic> 0), and the current supplied from the consumers 2a to 2c to the power supply system 1 is negative (current Ia ~ Ic <0).

Current sensor 16 is arranged between power storage device 12 and connection point B, and detects current Ibt (charging current to power storage device 12 or discharging current from power storage device 12) flowing to this position. Here, the current stored in power storage device 12 is positive (current Ibt> 0), and the current discharged from power storage device 12 is negative (current Ibt <0).

The control circuit 13 is composed of a microcomputer or the like, and mainly includes (1) control of the power storage device 12 and (2) a first electric energy charge indicating the amount of power supplied from the power supply system 1 to the consumers 2a to 2c. (2) Determination of the unit price of the second electricity amount indicating the amount of surplus power collected from the consumers 2a to 2c by the power supply system 1, and (3) Electricity calculated based on the determined unit price of the electricity rate Notification of charges.

(1) Control of power storage device 12 Control of the power storage device 12 will be described with reference to the drawings. FIG. 2 is a diagram illustrating a control flowchart of the power storage device 12. Control circuit 13 operates the charging / discharging circuit of power storage device 12 such that current value I obtained from current sensor 16 (here, the instantaneous current execution value is used) becomes zero.

The control circuit 13 detects the current I when the charge / discharge control is started (step S11), and determines whether or not the current I is positive (step S12). When the current I is positive in step S12, the power is supplied from the commercial power system 3 to the consumers 2a to 2c (a state where the demand for power wins the supply between the consumers 2a to 2c). Therefore, the command value Ibt * of the current Ibt flowing between the power storage device 12 and the connection point B is increased (step S13) so that the discharge current from the power storage device 12 increases (or the charging current decreases). To).

Thereafter, it is determined whether or not the command value Ibt * exceeds the current Ibtx that can be discharged by the battery (step S14). When the command value Ibt * exceeds the current Ibtx, the plus command value Ibt * is returned to the original (step S15), and the process proceeds to step S19. If the command value Ibt * does not exceed the current Ibtx, the process proceeds to step S19 as it is.

If the current I is not positive in step S12, the power is being supplied from the consumers 2a to 2c to the commercial power system 3 (the power supply is winning among the consumers 2a to 2c). ), The command value Ibt * of the current Ibt flowing between the power storage device 12 and the connection point B is lowered (step S16) so that the charging current from the power storage device 12 increases (or the discharge current decreases). To be)

Thereafter, it is determined whether or not the command value Ibt * exceeds the current Ibtm that can be charged by the battery (step S17). If the command value Ibt * exceeds the current Ibtm, the minus command value Ibt * is restored (step S18), and the process proceeds to step S19. If the command value Ibt * does not exceed the current Ibtm, the process proceeds to step S19 as it is.

In step S19, the control circuit 13 charges and discharges the power storage device 12 with the set command value Ibt * and returns to step S11. When Ibt * is positive, a discharging operation is performed, and when Ibt * is negative, a charging operation is performed. As described above, the power storage device 12 is operated by repeating Steps S11 to S19, so that a smooth flow does not occur from the commercial power system 3 to the consumers 2a to 2c and a reverse power flow occurs to the consumers 2a to 2c. I am trying not to.

(2) Unit Price Determination of Electricity Charge The control circuit 13 is connected to the Internet 4, and the unit price of the power purchase price when buying power from the commercial power system 3 and the power sale price when selling power to the commercial power system Function as a communication circuit (input circuit) for inputting the unit price. When the control circuit 13 acquires the unit price of the commercial power grid 3 and the unit price of the power sale fee, the unit price of the first power amount and the unit price of the second power amount are set to the unit price of the power purchase rate and the power sale fee Set to a value between For example, when the purchased power is 40 yen / kWh and the sold power is 20 yen / kWh, the unit price of the first power amount and the unit price of the second electricity amount are set to 30 yen / kWh. To do.

When the consumers 2a to 2c cannot cover their loads with the power generated by their solar cells 21a to 21c, they receive power from the power supply system at the unit price of the first power amount. On the contrary, when the generated power of the solar cells 21a to 21c is surplus, the consumers 2a to 2c sell power to the power supply system 1 at the unit price of the second power amount.

The power supply system 1 performs control so that power is not supplied from the commercial power system 3 to the consumers 2a to 2c by the control of the power storage device 12 in (1). However, when the power consumed by the load of the consumers 2a to 2c cannot be covered, the power is supplied from the commercial power system 3 to the consumers 2a to 2c. In this case, the unit price of the first power amount that is currently set may be increased. For example, the unit price of the first power amount in this case is made the same as the unit price of the power purchase fee. In addition, the control circuit 13 is connected to the Internet 4 and informs the display monitors 24a to 24c of the consumers 2a to 2c that are also connected to the Internet that the unit price of the electricity charge of the first electric energy is increasing. .

The power supply system 1 controls the power storage device 12 (1) so that the reverse flow of surplus power does not occur in the commercial power system 3 from the consumers 2a to 2c. Even if the surplus power of the consumers 2a to 2c cannot be absorbed, power flows backward from the consumers 2a to 2c to the commercial power system 3. In this case, the unit price of the second power amount that is currently set may be lowered. For example, the unit price of the second power amount in this case is made the same as the unit price of the power selling fee. In addition, the control circuit 13 notifies the display monitors 24a to 24c of the consumers 2a to 2c via the Internet 4 that the unit price of the electric charge of the second electric energy is decreasing.

(3) Notification of electricity charge The control circuit 13 calculates the electricity charge of the first electric energy and the electricity charge of the second electric energy for a predetermined period (for example, one month), and each demand via the Internet 4 It is configured to be able to display (notify) on display monitors 24a to 24c provided in the houses 2a to 2c. FIG. 3 shows a schematic diagram of the display monitor.

The display monitors 24a to 24c have a power display unit 31 and an LED unit 32. The power display unit 31 includes a first power amount for the predetermined period (for example, one month) (power purchased by the consumers 2a to 2c), an electric charge for the first power amount, and a second power amount (the customer 2a). ~ 2c electric power sold), the electric charge of the second electric energy, and the difference between them (the difference between the first electric energy and the second electric energy, and the electric charge of the first electric energy and the electric charge of the second electric energy) Difference) is displayed.

Each customer 2a to 2c confirms these electricity charges using a display monitor, and if the purchased power is larger than the sold power, the difference is paid. Also, if the purchased power is less than the sold power, the difference amount is received.

The LED unit 32 is turned on when receiving a notification from the control circuit 13 that the unit price of the first power amount is increasing or the unit price of the second power amount is decreasing. The lighting is performed when the unit price of the first electric energy is increased, such as lighting when the unit price of the first electric energy is increased and blinking when the unit price of the second electric energy is decreased. The unit price is different from the case where the unit price is lowered (the color to be lit may be changed).

The control circuit 13 calculates the first electricity charge based on the first electricity amount and the unit price of the first electricity charge. The first electric energy is obtained as follows. The current sensor 15 samples the currents Ia to Ic flowing from the power supply system 1 to the consumers 2a to 2c and integrates them for a predetermined period. Then, the first electric energy is calculated by multiplying the accumulated current by the voltage of the commercial power system 3 and the sampling time. That is, the control circuit 13 functions as a power amount detection circuit that detects the first power amount for each consumer.

Then, the unit price of the electricity charge of the first electric energy determined in (2) and the obtained first electric energy are integrated. Thereby, the electricity bill of the 1st electric energy can be calculated | required. In addition, when there is a period in which the unit price of the first power amount is increased, the calculation may be performed using the unit price of charges that has increased for the period.

The control circuit 13 calculates the electricity charge for the second electric energy based on the second electric energy and the unit price of the electricity charge for the second electric energy. The second electric energy is obtained as follows. The current sensor 15 samples the currents Ia to Ic flowing from the consumers 2a to 2c to the power supply system 1 and integrates them for a predetermined period. Then, the second electric energy is calculated by multiplying the accumulated current by the voltage of the commercial power system 3 and the sampling time. That is, the control circuit 13 functions as a power amount detection circuit that detects the second power amount for each consumer.

Then, the unit price of the electric charge of the second electric energy determined in (2) and the obtained second electric energy are integrated. Thereby, the electric bill of the 2nd electric energy can be calculated | required. In addition, when there is a period in which the unit price of the second electric energy is reduced, the calculation may be performed using the unit price of the charge that has decreased for the period.

As described above, the power supply system 1 distributes the surplus power among the plurality of consumers 2a to 2c to the consumers with insufficient power while suppressing the exchange of power with the commercial power system 3. As a result, power purchase and power sale can be performed between the plurality of consumers 2a to 2c via the power supply system 1. At this time, a power purchase fee (unit price of the first electricity amount) and a power sale fee (unit price of the first electricity amount) of the plurality of consumers 2a to 2c to which power is supplied from the power supply system 1 ) Is determined between the unit price of the power purchase fee and the unit price of the power sale fee of the commercial power system. And it is comprised so that the electricity bill of 1st electric energy and the electricity bill of 2nd electric energy can be notified to each consumer. As a result, each customer can purchase power at a lower price than when purchasing power from the commercial power grid when purchasing power, and at a higher price than when selling power to the commercial power system when selling power. You can sell electricity.

In addition, according to the present embodiment, when the electric power is supplied from the commercial power system 3 to the consumers 2a to 2c, the unit price of the electric charge of the first electric energy is increased. Thereby, the charge of the electric power supplied from the commercial power system 3 can be covered.

Further, according to the present embodiment, when power is supplied from the commercial power system 3 to the consumers 2a to 2c, the consumers 2a to 2c are informed that the unit price of the electricity charge of the first power amount has increased. (The LED portions of the display monitors 24a to 24c are lit). As a result, it is possible to confirm that the charges for actually purchasing power are increasing at each of the consumers 2a to 2c, and the consumers 2a to 2c who have confirmed this can save electricity and reduce the cost of the electricity charges. .

Further, according to the present embodiment, when surplus power collected from the plurality of consumers 2a to 2c cannot be consumed in the plurality of consumers 2a to 2c, the surplus power is sold to the commercial power grid 3, The unit price of the electricity charge of the second electric energy at the time is lowered. As a result, it is possible to prevent the charges sold by each of the consumers 2a to 2c from being increased by the amount of power sold to the commercial power system 3 at a low price, and the charges being not paid.

In addition, according to the present embodiment, when power is supplied from the commercial power system 3 to the consumers 2a to 2c, the consumers 2a to 2c are informed that the unit price of the second electricity amount is reduced. (The LED portions of the display monitors 24a to 24c blink). As a result, it is possible to confirm that the price for actually purchasing electricity has decreased at each of the consumers 2a to 2c, and the consumers 2a to 2c who have confirmed this have increased the necessary load and sold the surplus power at a low price. Can be prevented.

As mentioned above, although one embodiment of the present invention was described, the above explanation is for making an understanding of the present invention easy, and does not limit the present invention. It goes without saying that the present invention can be changed and improved without departing from the gist thereof, and that the present invention includes equivalents thereof.

For example, in the present embodiment, the solar cells 21a to 21c are used as the power generation apparatus, but various generators such as a fuel cell, a storage battery, a wind power generator, and an engine generator can be used.

DESCRIPTION OF SYMBOLS 1 Commercial power system 2 Customer 3 Commercial power system 4 Internet 12 Power storage device 13 Control device 14 Ammeter 15 Ammeter 21 Solar cell 22 Distribution board 23 Power conditioner 24 Display monitor 25 Load

Claims

Collecting surplus power that is not consumed by a plurality of consumers each having a power generation device, supplying the surplus power to the consumer that requests power, and insufficient power to supply the consumer that requests power In the case of a power supply system that obtains power from a commercial power system,
An input circuit for inputting a unit price of a power purchase fee for purchasing power from the commercial power system and a unit price of a power sale fee for selling power to the commercial power system;
A power amount detection circuit that detects, for each customer, a first power amount indicating the amount of power supplied to the consumer and a second power amount indicating the amount of surplus power collected from the consumer;
Setting the unit price of the electricity charge for the first amount of electricity and the unit price of the electricity charge for the second amount of electricity to a value between the unit price of the power purchase fee and the unit price of the power sale fee;
Based on the first power amount and the unit price of the first power amount, and the unit price of the first power amount and the unit price of the second power amount and the second power amount. An electric power supply system configured to be able to notify each customer of an electricity charge of the second electric energy calculated based on the electric charge.
2. The power supply system according to claim 1, wherein when power is supplied from the commercial power system to the consumer, a unit price of the electricity charge of the first power amount is increased.
3. The electric power according to claim 2, wherein when the electric power is supplied from the commercial electric power system to the consumer, the customer is notified that the unit price of the electric charge of the first electric power amount is increasing. Supply system.
When the surplus power collected from the plurality of consumers cannot be consumed within the plurality of consumers, the surplus power is sold to the commercial power system, and the unit price of the electric charge of the second power amount at this time is reduced. The power supply system according to any one of claims 1 to 3.
5. The power supply system according to claim 4, wherein when the surplus power is sold to a commercial power system, the consumer is informed that the unit price of the electricity charge of the second power amount is decreasing.