JP2007259598A - Power storage-supply device, and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power storage-supply device and method which can reduce electric bills. <P>SOLUTION: The power storage-supply device classifies loads into a first load 61 operating steadily, and a second load 63 operating on demand. A load controller 80 computes the residual power storage capacity Q(n) of a storage battery 10. Power is supplied from the storage battery 10 to the first load 61 and the second load 63, when the residual power storage capacity Q(n) is sufficient; and when Q(n) is not sufficient, power is supplied only to the first load 61. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power storage / power supply apparatus and method capable of supplying power to a load from a commercial power source and supplying power charged in a storage battery (battery) to the load.

  It has been practiced to provide a storage battery (battery) as an emergency power supply when a commercial power supply fails.

In order to effectively use such a storage battery, a power storage / power supply method is desired in which the storage battery is charged at night when the electricity rate is cheap, and the power stored in the storage battery is supplied to the load during the day when the electricity rate is high. Yes.
Such a demand is not limited to large-scale power facilities as in the past, but also occurs in ordinary households where power consumption is relatively small. For example, even in small-scale facilities such as homes, a power storage / power supply method is desired in which power is stored in a storage battery at night when the power charge is cheap, and the power stored in the storage battery is supplied to the load during the day when the power charge is high. ing.
In such a power storage / power supply device, measures for improving efficiency are taken.

  Japanese Patent Laid-Open No. 2001-8385 discloses a technique for selecting a plurality of load patterns in order to use nighttime power without waste.

  Patent Document 2 (Japanese Patent Application Laid-Open No. 2001-103678) discloses a method of calculating a power consumption of a load by an arithmetic unit by providing a current sensor for each load for the purpose of improving an operating rate of the inverter, and further calculating the power consumption by the arithmetic unit. A switching device that calculates a total value and further switches the load for each load is provided, and a technique for switching the load based on the total value of power consumption calculated by the arithmetic unit is disclosed.

  Patent Document 3 (Patent No. 03621853) is a technique aimed at peak cut by connecting a cooking heater, a room air conditioner (air conditioner), etc., to a power storage device and preferentially feeding a load that maximizes power consumption. Is disclosed.

JP-A-2001-8385 JP-A-2001-103678 Japanese Patent No. 03621853

  Since the technology disclosed in Patent Document 1 is a power supply target, for example, there are various household load patterns, for example, household power storage / power supply devices can handle load patterns. Therefore, there is a problem that the stored power of the storage battery cannot be used effectively.

Since the technique disclosed in Patent Document 2 includes a current sensor and a switching device for each load, there is a problem in that the configuration of the power storage system becomes complicated and the equipment price increases. Raising equipment prices is undesirable for equipment with relatively small loads, such as homes.
Further, since the load is frequently switched, there is a possibility that power may not be instantaneously supplied to the load at the time of switching. In particular, when an electronic device such as a computer is built in the load, it is not preferable that the power supply be momentarily cut off.

Further, regarding the technique described in Patent Document 2, if the load is frequently switched, it is difficult to grasp the connection state of the load, which is not preferable for maintenance.
Furthermore, in the technique disclosed in Patent Document 2, since only the capacity of the inverter is considered and the capacity of the storage battery is not monitored, the storage capacity cannot be effectively used.

  In the technique disclosed in Patent Document 3, the power supply equipment such as an inverter is enlarged, and the equipment is complicated because a switching device is required for each load. As a result, there is a problem that the price of the equipment becomes high.

As described above, the conventional techniques have many problems to be improved in view of the complexity of the configuration of the equipment, the high price of the equipment, and the effective use of the power stored in the storage battery.
As mentioned above, although the electric power storage / power supply device for home use has been mainly described, various problems to be improved have been encountered not only in the home electric power storage / power supply device but also in larger facilities.

The present invention does not increase the size of equipment, increase in price, does not take a complicated configuration, stores nighttime power with a low electricity bill in a storage battery, and effectively uses the stored power to reduce the electricity bill. It is an object of the present invention to provide a power storage and power supply apparatus and method.
Another object of the present invention is to reduce electricity bills by covering standby power with power stored in power consumption.

FIG. 1 shows the results of a survey on household standby power described in the former Ministry of International Trade and Industry, Institute of Industrial Technology, News 1999, No. 12. According to the results of this survey, each household is roughly divided into the amount of power supplied to a load that consumes power almost constantly, such as a refrigerator, standby power required during a predetermined time of day, and other power. I understand that
Of course, this power distribution varies from one household to another, and also varies depending on the season in each household. For example, in summer, the use of room air conditioners (air conditioners) increases, so the power distribution changes.

Furthermore, it is known that power consumption varies depending on the time zone even in the same period (season).
For example, in an ordinary household, as illustrated in FIG. 2, the power consumption usually increases with getting up, and the power consumption continues to peak until going to work or going to school. Thereafter, the power consumption decreases during the daytime, but the power consumption peaks again from the return time to bedtime. In addition, power consumption decreases at night. Such a cycle continues every day.

  What can be inferred from the data illustrated in FIG. 1 and FIG. 2 is (1) a steady load that consumes electric power almost always, such as a refrigerator, but (2) On-demand load that changes depending on the usage time or usage conditions such as lighting fixtures, TV receivers, microwave ovens, cooking heaters, etc. (3) Seasons like winter and summer, for example, air conditioners for air conditioning It can be seen that the load is roughly classified according to the load and used depending on the time zone.

The power consumption of such a load will first be considered in terms of power charges.
Of the regular loads, for the loads with comparatively low power consumption that can be covered by the storage capacity of the storage battery, if the power stored in the storage battery is used for the night power, the electricity charge will be reduced. Of course, it is in the range of the allowable power storage amount of the storage battery because it is desired to avoid the increase in the initial cost due to the large storage battery.
For on-demand loads, if there is surplus power in such a storage battery, the surcharge can be supplied by supplying the surplus power. When there is no surplus power in the storage battery, power supply from a commercial power source is unavoidable.
On the other hand, since it is practically difficult to feed power from a storage battery to a load having a large current capacity and power consumption such as an air conditioner, a commercial power source is used.

Next, we consider from the aspect of equipment.
Assuming maximum daily power consumption (peak power consumption), facilities such as storage batteries, inverters for charging storage batteries (power converters), and converters that convert storage battery storage to commercial frequency alternating current (reverse power) Converter), power supply system, for example, the thickness of the power supply line, the breaking capacity of the changeover switch, etc., increase the scale of these devices and increase the price of the devices. Moreover, since the market price range in which electric power peaks during a day is limited and the ability to use is limited, usage efficiency is low. For example, if it is assumed that a storage battery is prepared for peak power, a very large storage battery is required, which is not realistic.
On the other hand, a storage battery, an inverter / converter, or the like that can supply power to at least a load that is stationary but relatively low in power consumption, such as a refrigerator, or to all or part of the on-demand load described above if possible These facilities are small-scale.

In summary, the load is preferably as shown in FIG. 3, for example, (1) a load that can cover the storage capacity of the storage battery with a steady load such as a refrigerator (this is referred to in the present invention). (Referred to as a first load), (2) a load that is likely to be covered by surplus power of the storage battery among on-demand loads (this is referred to as a second load in the present invention), and (3) stored power of the storage battery. It is difficult or impractical to use, and classify it into a general load other than the above (this is called a general load in the present invention) and separate these power supply systems.
As described above, the second load is fed from the storage battery when the surplus power of the storage battery can be fed, and from the commercial power source when feeding from the storage battery is difficult.
For general loads, power is supplied only from a commercial power source.

The present invention is characterized in that power is supplied to the first load and the second load as follows based on the above technical idea.
The power storage / feed device of the present invention is:
A storage battery, a bidirectional power conversion unit capable of converting a commercial power source into DC power that can be charged to the storage battery, and reversely converting the power charged in the storage battery into substantially the same AC power as the commercial power source, and A current sensor for detecting a charging current and a discharging current for the storage battery; a first load power supply line for guiding output power of the bidirectional power conversion unit to the first load; and a second connected to the second load. A power feed system changeover switch, wherein a load feed line and a first input terminal are connected to the commercial power source, a second input terminal is connected to the first load feed line, and an output terminal is connected to the second load feed line And a load control device,
The load control device includes:
Storing the predicted power amount and power margin of the first load;
Based on the charging current and discharging current detected by the current sensor, the charging power amount and discharging power amount to the storage battery are calculated, and the discharging power amount is subtracted from the storing power amount to calculate the remaining storage capacity of the storage battery. And
The power feeding is performed so that the first load and the second load are fed from the storage battery when the remaining storage capacity of the storage battery is equal to or greater than the sum of the predicted power amount of the first load and the power margin. The system switch is driven, and when the remaining storage capacity of the storage battery is equal to or less than the sum of the predicted power amount of the first load and the power margin, the power is supplied from the storage battery only to the first load. Drive the power feeding system selector switch,
Calculating an integrated value of the electric energy of the second load;
When the remaining storage capacity of the storage battery is equal to or greater than the sum of the predicted power amount of the first load and the integrated value of the power amount of the second load, power is supplied from the storage battery to the first load and the second load. When the power supply system changeover switch is driven and the remaining storage capacity of the storage battery is equal to or less than the sum of the predicted electric energy of the first load and the integrated value of the electric energy of the second load, the first The power feeding system changeover switch is driven so that only the load is fed from the storage battery.

Moreover, the power storage / power feeding method of the present invention for feeding power to the first load and the second load is as follows:
Calculating the amount of stored power to the storage battery, calculating the amount of discharged power from the storage battery, and subtracting the amount of discharged power from the amount of stored power to calculate the remaining storage capacity of the storage battery;
When the remaining storage capacity of the storage battery is greater than or equal to the sum of the predicted power amount of the first load and a preset power margin, the first load and the second load are fed from the storage battery, A power feeding system changeover switch is driven so that only the first load is fed from the storage battery when the remaining storage capacity of the storage battery is equal to or less than the sum of the predicted power amount of the first load and the power margin. , Driving the power feeding system changeover switch,
Calculating an integrated value of the electric energy of the second load;
When the remaining storage capacity of the storage battery is equal to or greater than the sum of the predicted power amount of the first load and the integrated value of the power amount of the second load, power is supplied from the storage battery to the first load and the second load. Driving the power feeding system changeover switch so that the first load when the remaining storage capacity of the storage battery is less than or equal to the sum of the predicted power amount of the first load and the integrated value of the power amount of the second load The power feeding system changeover switch is driven so that power is fed only from the storage battery.

According to the present invention, there is no increase in equipment size, price increase, complicated structure, night electricity with a low electricity bill is stored in the storage battery, and the stored electricity is effectively used to reduce the electricity bill. It becomes possible.
Moreover, according to this invention, it can cover with the electric power which stored little standby electric power among electric power consumption, and can reduce an electricity bill.

First Embodiment A first preferred embodiment of the power storage / feed device of the present invention will be described with reference to FIG.
The power storage / power feeding device 1 includes a storage battery 10, a bidirectional power conversion unit 20, a charging / non-charging / switching switch 41, a power feeding system switching switch 43, a charging timer 50, a first current sensor 71, A second current sensor 73 and a load control device 80 are included.

Load Classification The load unit 60 fed by the power storage / feed device 1 is classified into a first load 61, a second load 63, and a general load 65.
The first load 61, for example, operates almost constantly like a refrigerator at home and needs constant power supply, but its power consumption is relatively small, and sufficient power can be supplied without using the large storage battery 10. This level of load is applicable. The first load 61 can include a plurality of loads in addition to the refrigerator.
The second load 63 does not always operate, but is one or a plurality of loads having a power capacity that can be operated with surplus power of the storage battery 10 among loads (on-demand loads) that operate at a predetermined time zone every day. . The surplus power of the storage battery 10 means surplus power after being supplied to the first load 61.
The general load 65 is used according to the season, for example, like an air conditioner, operates for a relatively long time when used, and uses a large amount of power, and the power stored in the power storage battery 10 is desired. This refers to a load that consumes a large amount of power that cannot be continuously supplied over time. Examples of such a general load 65 include an air conditioner, a device using a heater such as a cooking heater that may be used every day, a microwave oven, and the like.

As described above, when implementing the power storage / feeding device of the present invention, for example, for each household, for each season, and for each day, the power consumption status of various loads is measured or predicted. The first load 61, the second load 63, and the general load 65 are classified according to the capacity of the storage battery 10.
In other words, the storage battery 10 is first selected to have a specification having a power capacity capable of supplying power to the first load 61. Preferably, the capacity of the storage battery 10 is selected so as to have a power capacity capable of supplying power to the second load 63 in addition to the power capacity supplying power to the first load 61.

Power Supply (Distribution) System With such load classification, the power storage / power supply apparatus 1 designs a power supply system as follows.
The power storage / power supply device 1 has a power distribution unit (distribution panel) 90 for branching commercial power supplied from the commercial power source 30 via the main power supply line 91. Separate as above.
Commercial power is directly supplied to the general load 65 from the power distribution unit 90 via the general load power supply line 93. Note that the commercial load is always supplied from the commercial power source 30 via the main power supply line 91 and the general load power supply line 93 to the general load 65, and thus is not subject to control by the load control device 80 described below.
Commercial power obtained by converting the DC voltage of the storage battery 10 in the bidirectional power conversion unit 20 is supplied to the first load 61 via the storage battery storage power feed line 97.
The second load 63 passes through the second load / first feed line 94a and the second load / second feed line 94b when the selection switch of the first feed system changeover switch 43 is selected as the contact A. When commercial power from the commercial power source 30 is supplied and the selection switch is selected as the contact B, the commercial power obtained by converting the DC voltage of the storage battery 10 in the bidirectional power conversion unit 20 is the same as the first load 61. Supplied via the second load / second feeder 94b.

The load control device 80 includes a calculation unit 81, a storage unit 83, and a control unit 85.
The load control device 80 is preferably configured by a computer.

The bidirectional power conversion unit 20 includes an inverter (power converter) and a converter (power reverse converter). In a charging period, for example, a charging period in which the power charge from 11:00 to 7:00 am in the next morning is low (midnight charge), the charging / non-charging / switching switch 41 is closed by the charging timer 50 (in the ON state) ) When charging the storage battery 10, the inverter converts the commercial frequency AC voltage from the commercial power source 30 into a DC voltage. On the other hand, for example, when power is supplied from the storage battery 10 to the first load 61, the converter converts the DC voltage of the storage battery 10 into an AC voltage of commercial frequency.
In the present embodiment, the inverter and the converter are collectively illustrated as the bidirectional power conversion unit 20, but the inverter and the converter may be integrated or separated.

Schematic operation of power storage / power supply device Charging The charging timer 50 closes the charging / non-charging / switching switch 41 during the charging period, for example, during the charging period when the power charge from 11:00 to 7:00 am in the next morning is low (midnight charge). ). Thereby, the path of the commercial power source 30, the charging / non-charging / switching switch 41, the inverter in the bidirectional power conversion unit 20, the current sensor 71, and the storage battery 10 is formed, and the inverter is connected to the commercial frequency from the commercial power source 30. The storage battery 10 is charged by converting the AC voltage into a DC voltage.
At this time, the first current sensor 71 detects the charging current.
The calculating means 81 of the load control device 80 calculates the charging power Qc for the storage battery 10 from the charging current Ic detected by the first current sensor 71 by, for example, a current integrating method, and stores it in the storage means 83.

  Note that the charging timer 50 is deleted, the charging time is managed by, for example, the calculation means 81 in the load control device 80, and the charging period, for example, the control means 85 activates the charging / non-charging / switching switch 41 ( The charging of the storage battery 10 can also be controlled by turning on or off (turning off).

2. Discharge Power is supplied to the first load 61 through the path of the storage battery 10, the first current sensor 71, the converter in the bidirectional power conversion unit 20, and the storage battery storage power supply line 97.
The converter converts the DC voltage of the storage battery 10 into an AC voltage having the same commercial frequency as that of the commercial power source 30, and the converted AC voltage having the commercial frequency is applied to the main power supply line 91.
At this time, the first current sensor 71 detects the discharge current Id flowing from the storage battery 10 to the first load 61.
From the discharge current Id detected by the first current sensor 71 by the calculation means 81 of the load control device 80, for example, the discharge power Qd from the storage battery 10 is calculated and stored in the storage means 83 by a current integration method.
When the detected current value of the first current sensor 71 is positive, it means the charging current Ic, and when it is negative, it means the discharging current Id.

  The calculation means 81 obtains the current storage capacity of the storage battery 10 by subtracting the discharge power Qd from the storage battery 10 from the charge power Qc to the storage battery 10 stored in the storage means 83.

  The first power supply system changeover switch 43 has a contact (contact) selected as the contact A or the contact B in accordance with the first switching signal SW1 from the control means 852 of the load control device 80. When the first power supply system changeover switch 43 is selected as the contact A, the second load 63 is supplied with power from the commercial power source 30. When the contact B is selected, the storage battery 10 and the bidirectional power conversion unit are selected. Power is supplied through 20 converter paths.

Operation of Load Control Device The operation of the load control device 80 will be described with reference to FIG.
FIG. 5 is a flowchart showing the operation of the load control device 80.

Step 1, the update calculation means 81 for the current storage capacity Q (n) of the storage battery 10 calculates the current n storage capacity Q (n) of the storage battery 10 when the charging time has ended, and stores it in the storage means 83. Remember.
As described above, the calculation means 81 integrates the charging power Qc to the storage battery 10 calculated from the charging current Ic detected by the first current sensor 71 during the charging period while the power storage / power supply device is operating. I will do it.
The computing means 81 calculates the remaining storage capacity Q (n) of the storage battery 10 immediately after the end of the charging period by subtracting the discharge power Qd of the previous day from the charging power Qc to the storage battery 10, for example, and the storage means 83 To remember. Of course, the remaining storage capacity Q (n) of the storage battery 10 is within the full charge capacity of the storage battery 10.

Step 2, the prediction calculation means 81 of the first load power amount Q1 predicts the power amount Q1 consumed by the first load 61 within the discharge period of the storage battery 10 today immediately after the end of the charging period.
As illustrated in FIG. 6, the calculation unit 81 measures the actual first load power amount Q <b> 1 within the daily discharge period and stores it in the storage unit 83. The calculation means 81 can predict the power amount Q1 of the first load of today by averaging the actual power amount Q1 of the first load within the plurality of daily discharge periods stored in the storage means 83. Alternatively, the calculation means 81 can also predict the actual first load power amount Q1 within the discharge period of the previous day as the current first load power amount Q1.
Alternatively, by storing an approximate value of the first load power amount Q1 for each season in the storage unit 83 in advance, the first load power amount Q1 is determined as the current predicted first load power amount. It can also be used as Q1.

Step 3: The surplus power comparison calculation means 81 checks whether or not the remaining storage capacity Q (n) of the storage battery 10 is larger than the power amount Q1 of the first load and the power margin Qα.
The power margin Qα is smaller than the total daily energy Q2 of the second load 63, and how much power can be supplied from the storage battery 10 to the second load 63 in addition to the first load 61. This refers to the surplus power that is shown.
The power margin Qα is, for example, a value from 20% or more of the second load power amount Q2 to the second load power amount Q2. Alternatively, the power margin Qα can be set to, for example, 20% of the power amount Q1 of the first load. The power margin Qα is set to, for example, 20% of the second load power amount Q2 or 20% of the first load power amount Q1 by supplying power to the second load 63. This is a margin value for preventing the remaining storage capacity Q (n) of the ten storage batteries 10 from becoming insufficient and supplying power to the first load 61 itself.
In other words, when power is supplied from the storage battery 10 to the second load 63, a certain margin of the remaining storage capacity Q (n) of the storage battery 10 is taken.

Step 4: Only the first load power supply calculating means 81 has the remaining storage capacity Q (n) of the storage battery 10 less than the sum of the power amount Q1 of the predicted first load of the day and the power margin Qα. When it is determined, the control means 85 outputs the first switching signal SW1 so as to select the contact (contact) of the first power feeding system changeover switch 43 as the contact A.
Thereby, the power supply from the storage battery 10 is performed only to the first load 61, and the second load 63 is supplied from the commercial power source 30.

Step 5: The power supply calculating means 81 for the first load and the second load determines that the remaining storage capacity Q (n) of the storage battery 10 is the predicted first-day power amount Q1 and power margin Qα of the first load. When it is determined that there is more power than the sum of the power, the remaining storage capacity Q (n) of the storage battery 10 supplies power to the first load 61, and there is surplus power to supply power to the second load 63. The control means 85 outputs the first switching signal SW1 so that the first power feeding system changeover switch 43 selects the contact B.
Thereby, the power supply from the storage battery 10 is performed to the first load 61 and the second load 63.

Step 6: The measurement calculation means 81 for the power amount Q2 of the second load continuously inputs the discharge current Id detected by the first current sensor 71, integrates the discharge current Id, and calculates the power of the second load. The quantity Q2 is calculated.
In the power storage / feed device 1 illustrated in FIG. 1, the discharge current Id is a discharge current from the storage battery 10 indicating power consumption in the first load 61 and the second load 63, and only the second load 63. The second load power amount Q2 cannot be obtained directly.
However, since the power amount Q1 of the first load is known by prediction, the predicted first load power amount Q1 is subtracted from the discharge power amount of the storage battery 10 obtained by the calculation means 81 integrating the discharge current Id. Then, the electric energy Q2 of the second load can be estimated.
Then, the calculation means 81 integrates the second load power amount Q2 obtained as described above and stores it in the storage means 83.

Step 7: The remaining storage capacity Q (n) check calculation means 81 of the storage battery 10 calculates the second load power amount Q2 obtained by integrating the remaining storage capacity Q (n) of the storage battery 10 with the first load power amount Q1. Check if it is greater than the sum of.
It is checked whether or not the remaining power storage capacity Q (n) of the storage battery 10 is greater than the sum of the first load power amount Q1 and the integrated second load power amount Q2.
When the remaining storage capacity Q (n) of the storage battery 10 is larger than (the sum of the first load power amount Q1 and the integrated second load power amount Q2), the remaining storage capacity Q (n ) Has a margin to supply power to the second load 63, the control means 85 continues the state where the contact of the first power supply system changeover switch 43 selects the contact B.
During this period, the calculation means 81 continues to integrate the power amount Q2 of the second load.

Step 8: The power supply calculating means 81 only for the first load 61 determines that the remaining storage capacity Q (n) of the storage battery 10 is the sum of the first load power amount Q1 and the integrated second load power amount Q2. ), The remaining storage capacity Q (n) of the storage battery 10 is determined to have no room to supply power to the second load 63. Therefore, the control unit 85 outputs the first switching signal SW1 so that the contact of the first power feeding system changeover switch 43 selects the contact B and power is supplied only from the storage battery 10 to the first load 61.

Steps 9 and 10: The discharge end check calculation means 81 checks whether or not the charging time zone has been reached.
When the charging time zone is reached, only the discharge from the storage battery 10 ends.
If the remaining storage capacity becomes close to zero before the end of discharging, the charging / non-charging / switching switch 41 is forcibly turned on by the calculation means 81 or the control means 85 to start charging. . Thereby, the electric power feeding to the 1st load 61 is performed reliably.

Step 11 When the update charging time zone of the remaining storage capacity Q (n) of the storage battery is reached, the charging / non-charging / switching switch 41 is closed by the charging timer 50 or by the calculation means 81. Thereby, the storage battery 10 is charged through the path of the commercial power source 30, the charging / non-charging / switching switch 41, the inverter, the first current sensor 71, and the storage battery 10.
The calculating means 81 calculates the storage capacity of the storage battery 10 by continuously inputting the charging current Ic detected by the first current sensor 71 and integrating the charging current Ic.

The operation described above will be described with reference to FIGS.
FIG. 7 shows a state in which a substantially constant amount of power is supplied to the first load 61. On the other hand, the second load 63 is supplied with power from the storage battery 10 during the first demand operation, and during the second demant operation, it is shown that power is supplied from the storage battery 10 halfway. Thereafter, since the remaining storage capacity Q (n) of the storage battery 10 cannot afford to supply power to the second load 63, power supply from the storage battery 10 to the second load 63 is stopped, and the commercial power source 30 Power is supplied.

FIG. 8 shows the consumption state of the stored power capacity of the storage battery 10 by the first load 61 and the second load 63. The power amount Q1 of the first load increases almost proportionally with the passage of time. The amount of power Q2 of the second load is consumed when power is supplied from the storage battery 10.
From the storage battery 10 within a range in which the total of the first load power amount Q1 and the integrated second load power amount Q2 does not exceed the remaining storage capacity Q (n) of the storage battery 10 in consideration of the power margin Qα. Is consumed.

In this way, the power stored in the storage battery 10 is supplied to the first load 61 and the second load 63 as much as possible during the charging time period (charging period).
Since the power charge during the charging time period is low, the price of the power consumed by the first load 61 and the second load 63 is low.

In the power storage / feed device according to the first embodiment of the present invention, the load unit 60 is classified into a first load 61, a second load 63, and a general load 65. A power distribution system is prepared with the load power supply line 94 (second load / first power supply line 94a, second load / second power supply line 94b) and the storage battery storage power power supply line 97, and a load control device 80 is provided to By performing the control process, the charge of power consumed by the load unit 60 can be reduced.
The configuration of the power storage / power feeding device 1 is also relatively low because only the load control device 80, the first current sensor 71, the second current sensor 73, and the first power feeding system changeover switch 43 are provided.
Furthermore, the storage battery 10 only needs to have the power supply capability of the first load 61 at least, and the power supply to the second load 63 is performed only when surplus power exists in the storage battery 10, so the equipment of the storage battery 10 needs to be enlarged. There is no. Therefore, the bidirectional power conversion unit 20 does not need to have a large capacity. Of course, it is not necessary to increase the current capacity of the wiring from the power distribution unit (distribution panel) 90.

First Modified Embodiment of First Embodiment In the above-described embodiment, the first current sensor 71 measures the discharge current Id fed from the storage battery 10 to the first load 61 and the second load 63. Said. In this case, for example, the electric energy Q2 of the second load in Step 6 could not be directly detected.
In order to improve this and calculate the accurate second load electric energy Q2, as illustrated in FIG. 9, the contact B of the first power supply system changeover switch 43 and the node of the storage battery storage power supply line 97 are used. A third current sensor 75 is provided between N4 and the discharge current flowing from the storage battery 10 to the second load 63, and the discharge current is integrated in the calculation means 81. It is also possible to calculate the amount of power Q2 of the second load supplied to.

Second Modification of the First Embodiment Of course, as illustrated in FIG. 10, the second current sensor 73 is connected between the node N4 and the first load 61, and the third current sensor 75 is connected to the first current sensor 75. If it is connected between the contact point A of the power feeding system changeover switch 43 and the coarse 63 and the current by the second current sensor 73 is integrated in the calculation means 81, the electric energy Q1 of the first load can be calculated. If the current from the third current sensor 75 is integrated, the power amount Q2 of the second load can be calculated.
When two current sensors are used, the power amount Q1 of the first load and the power amount Q2 of the second load can be separated and accurately calculated independently, so the configuration illustrated in FIG. 10 is desirable.

Second Embodiment A second embodiment of the power storage / feeding device of the present invention will be described with reference to FIG.
In the first and second embodiments described above, an example has been described in which the storage battery 10 is assumed to be able to sufficiently supply power to the first load 61.
However, in the initial state of the power storage / power supply device 1, the storage battery 10 does not have sufficient power storage and cannot supply power to the first load 61.
Thus, in order to operate the first load 61 in the initial state, as illustrated in FIG. 11, in the power storage / power feeding device 1 illustrated in FIG. 4, a second power feeding system changeover switch 45 is further provided. The first load 61 can be fed directly from the commercial power source 30.
In addition, by providing the second power feeding system changeover switch 45, the first load 61 can be operated during maintenance of the storage battery 10 in addition to the initial state described above.
In this case, it is desirable to provide a switch 46 that interlocks with the second power feeding system changeover switch 45. Thereby, it is possible to prevent the stored power from flowing back to the system.
Further, these switches 45, 46 are controlled in conjunction with the charging / non-charging / switching switch 41 by the control means 75, for example, and the second power feeding system switching switch 45 is turned on and the switch 46 is turned off during the charging time period. Power can be supplied efficiently without using a converter or inverter.
The third embodiment to which the second power feeding system changeover switch 45 is added can be applied to the power storage / power feeding device 1 illustrated in FIGS. 9 and 10 in addition to the power storage / power feeding device 1 illustrated in FIG. .

The charging of the storage battery 10 according to the third embodiment is possible not only when the electric power from the commercial power source 30 is performed only at night, but also when the battery is charged from a solar battery that is generated by sunlight.
FIG. 12 illustrates such a power storage / feed device 1A.
The power storage / power supply device 1A includes a solar cell unit 110, a DC / DC converter 120, a third power supply system changeover switch 130, and a fourth current sensor 140 in addition to the power storage / power supply device 1 illustrated in FIG. Have been added.
The DC / DC converter 120 converts the DC power generated by the solar cell unit 110 into the voltage level of the storage battery 10. The third power feeding system changeover switch 130 connects the output of the DC / DC converter 120 to the storage battery 10. Thereby, the storage battery 10 is also charged with the electric power generated by the solar cell unit 110.
The fourth current sensor 140 measures the charging current Ic2 at that time.
Although the 3rd electric power feeding system changeover switch 130 is not essential, when the electric power of the solar cell unit 110 is charged to the storage battery 10, it will be in an ON state. The third power feeding system changeover switch 130 can be turned on / off manually or can be turned on / off from the control means 85.

The calculation means 81 of the load control device 80 calculates the charge amount Q4 (n) from the solar cell unit 110 by integrating the charging current Ic2 detected by the fourth current sensor 140. The calculation unit 81 continuously calculates the charge amount Q4 (n).
The calculating means 81 adds the charge amount Q4 (n) to the current storage capacity Q (n) of the storage battery 10 (or the remaining storage capacity Q (n) of the storage battery 10). Thereby, the current remaining storage capacity Q (n) of the storage battery 10 is updated.

In the third embodiment, for example, the storage battery 10 is not only supplied with power from the commercial power source 30 at night when electricity charges are cheap, but also charged from a solar battery that is generated by sunlight, such as in the daytime. The possibility of power feeding to the second load 63 is significantly increased.
Therefore, the range of selection of the second load 63 is widened, for example, a cooking heater, a microwave oven, and the like are more likely to be usable by power supply by the storage battery 10.
Furthermore, as described in the first embodiment, power is supplied to the first load 61 without determining the period such as the charging period and the discharging period, and the remaining storage capacity Q (n As long as there is), power can be supplied to the second load 63.

  The third embodiment in which the solar cell unit 110, the DC / DC converter 120, the third power feeding system changeover switch 130, and the third current sensor 140 are added is not limited to the power storage / power feeding device 1 illustrated in FIG. The present invention can also be applied to the power storage / feed device illustrated in FIGS. 9, 10, and 11.

The implementation of the power storage / feeding device of the present invention is not limited to the above-described embodiment, and various modifications can be made. Of course, the above-described embodiments can be appropriately combined.
In addition, although embodiment mentioned above described the electric power storage and electric power feeding apparatus applied to a household as an example, the electric power storage and electric power feeding apparatus of this invention is not limited to application to a home. It is obvious that the power storage / feeding device of the present invention can be applied to various facilities having an electric load.

FIG. 1 is a graph showing the results of a survey on standby power at home. FIG. 2 is a graph illustrating an exemplary situation of daily power consumption. FIG. 3 is a graph illustrating load classification. FIG. 4 is a configuration diagram of the first embodiment of the power storage / feeding device of the present invention. FIG. 5 is a flowchart showing the processing of the load control device in FIG. FIG. 6 is a graph showing an example of how to obtain the predicted electric energy of the first load by the load control device illustrated in FIG. FIG. 7 is a graph showing an example of a power supply state to a load by the power storage / power supply apparatus illustrated in FIG. FIG. 8 is a graph showing an example of a consumed capacity Q (n) state due to power feeding to a load by the power storage / power feeding device illustrated in FIG. FIG. 9 is a block diagram showing a first modification of the first embodiment of the power storage / feed device of the present invention. FIG. 10 is a block diagram showing a second modification of the first embodiment of the power storage / feed device of the present invention. FIG. 11 is a block diagram showing a second embodiment of the power storage / feeding device of the present invention. FIG. 12 is a block diagram showing a third embodiment of the power storage / feeding device of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A ... Electric power storage and electric power feeder 10 ... Storage battery, 20 ... Bidirectional power conversion unit, 30 ... Commercial power source 41 ... Charging / non-charging / switching switch,
43, 45 ... Feeding system selector switch,
50: Charging timer,
60 ... load section, 61 ... first load, 63 ... second load
65 ... General loads 71, 73, 75 -... Current sensor 80 ... Load control device
81 ... Calculation means, 83 ... Storage means, 85 ... Control means
SW1 ... 1st switching signal 90 ... Power distribution unit (distribution panel)
91 ... Main feed line, 92 ... Split line, 93 ... General load feed line
94 …… Second load feeder line,
94a ... 2nd load and 1st feeder
94b ... second load / second feeder
95 ... Power supply line for charging
95a ... 1st feeder for charge
95b ... Second feed line for charging
96 ... Charge / discharge wire
97 ... Storage battery storage power feeder 110 ... Solar cell unit, 120 ... DC / DC converter 130 ... Third feeding system changeover switch, 140 ... Fourth current sensor Q1 ... First load electric energy Q2 ... Second load Amount of power Q (n): Remaining (current) storage capacity of storage battery Qα: Power margin

Claims (6)

A power storage / feeding device for feeding power to a first load and a second load,
A storage battery,
A bidirectional power conversion unit that converts commercial power into direct-current power that can be charged into the storage battery, and that can reversely convert the power charged in the storage battery into substantially the same alternating-current power as the commercial power supply;
A current sensor for detecting a charging current to the storage battery;
A first load feeder that guides output power of the bidirectional power conversion unit to the first load;
A second load feeder connected to the second load;
A feed system changeover switch having a first input terminal connected to the commercial power source, a second input terminal connected to the first load feed line, and an output terminal connected to the second load feed line;
A load control device,
The load control device includes:
Storing the predicted power amount and power margin of the first load;
Based on the charging current and discharging current detected by the current sensor, the charging power amount and discharging power amount to the storage battery are calculated, and the discharging power amount is subtracted from the charging power amount to calculate the remaining storage capacity of the storage battery. And
The power supply system so that the first load and the second load are fed from the storage battery when the remaining storage capacity of the storage battery is equal to or greater than the sum of the predicted power amount of the first load and the power margin The changeover switch is driven, and when the remaining storage capacity of the storage battery is equal to or less than the sum of the predicted power amount of the first load and the power margin, the power is supplied from the storage battery only to the first load. Drive the power feeding system selector switch,
Calculating an integrated value of the electric energy of the second load;
When the remaining storage capacity of the storage battery is equal to or greater than the sum of the predicted power amount of the first load and the integrated value of the power amount of the second load, power is supplied from the storage battery to the first load and the second load. And when the remaining storage capacity of the storage battery is equal to or less than the sum of the predicted electric energy of the first load and the integrated value of the electric energy of the second load, Driving the power feeding system changeover switch so that only one load is fed from the storage battery;
Power storage / power supply device. The load control device includes:
Subtracting the predicted power amount of the first load from the discharge power amount from the storage battery issued based on the discharge current detected by the current sensor to calculate an integrated value of the power amount of the second load;
The power storage / feeding device according to claim 1. A second current sensor is provided between the storage battery storage power feed line and the second input terminal of the feed system changeover switch;
The load control device calculates an integrated value of the electric energy of the second load based on the current detected by the second current sensor;
The power storage / feeding device according to claim 1. Provided between the commercial power source and the storage battery, and having a charging / non-charging / switching switch for connecting a commercial power source to the bidirectional power conversion unit during a charging period of the storage battery,
The power storage / feeding device according to claim 1. A solar cell unit,
A DC / DC converter that converts electric power generated by the solar cell unit into electric power that can be charged in the storage battery;
A third current sensor for detecting a charging current from the DC / DC converter to the storage battery;
The load control device calculates charging power from the solar cell unit to the storage battery based on a charging current detected by the third current sensor,
The power storage / feeding device according to any one of claims 1 to 4, wherein the calculated storage power from the solar cell unit is added to the remaining storage capacity of the storage battery to be updated as a new remaining storage capacity of the storage battery. A power storage / feeding method for feeding power to a first load and a second load,
Calculating the amount of stored power to the storage battery, calculating the amount of discharged power from the storage battery, and subtracting the amount of discharged power from the amount of stored power to calculate the remaining storage capacity of the storage battery;
When the remaining storage capacity of the storage battery is equal to or greater than the sum of the predicted power amount of the first load and a preset power margin, power is supplied so that power is supplied from the storage battery to the first load and the second load. The system switch is driven, and when the remaining storage capacity of the storage battery is equal to or less than the sum of the predicted power amount of the first load and the power margin, the power is supplied from the storage battery only to the first load. Drive the power feeding system selector switch,
Calculating an integrated value of the electric energy of the second load;
When the remaining storage capacity of the storage battery is equal to or greater than the sum of the predicted electric energy of the first load and the integrated value of the electric energy of the second load, power is supplied from the storage battery to the first load and the second load. When the power supply system changeover switch is driven and the remaining storage capacity of the storage battery is equal to or less than the sum of the predicted electric energy of the first load and the integrated value of the electric energy of the second load, the first Driving the power feeding system changeover switch so that only the load is fed from the storage battery,
Power storage and power supply method.

Images