JPH11178237A - Household power supply system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To use photovoltaic power, midnight power, and general power in the order of lowest cost, and to make full use of the photovoltaic power to achieve significant cost reduction. SOLUTION: The electric power obtained by a solar power generation device 9 is compared with the costs of late-night electric power and general electric power of an external system 1, and electric power with lower cost is preferentially used for the residential electric equipment 3.
Then, the power is supplied to the residential storage battery 5 and the vehicle storage battery 21 of the electric vehicle 20, and the surplus of the solar power is transmitted to the external system 1 and sold, so that a significant cost reduction can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a household power supply system.

[0002]

2. Description of the Related Art Conventionally, as shown in, for example, Japanese Unexamined Patent Publication No. 5-95639, an external power system transmitted from a power company for the purpose of reducing the power consumption cost has been included in a home power supply system. In addition to accumulating late-night power in residential storage batteries to make it possible to use low-cost late-night power, it is also possible to use power obtained by solar power generation equipment that costs nothing other than initial costs. Is known.

[0003]

However, in the above-described system, when the storage battery for a house or the storage battery of an electric vehicle is fully charged, or when the power consumption of the house electrical equipment during the day is small, the angle of the solar battery is low. Even if the power is generated by the photovoltaic power generator, the generated power is not only wasted, but also the power used in the time zone from evening to midnight is large, and the power stored in the residential battery during the day is insufficient. In such a case, the shortage must be compensated for by the late-night power, which eventually increases the late-night power usage fee.

Accordingly, the present invention uses the power obtained by photovoltaic power generation, the late-night power of an external system transmitted from a power company, and general power in the order of the lowest cost to reduce the cost. It is an object of the present invention to provide a household power supply system that can make full use of the power obtained by photovoltaic power generation and realize significant cost reduction.

[0005]

According to the first aspect of the present invention, the cost of the power obtained by photovoltaic power generation, the midnight power of the external system, and the general power of the external system are compared.
Inexpensive power can be preferentially supplied to residential electrical equipment, residential storage batteries and / or vehicle storage batteries for electric vehicles, and surplus power obtained by solar power generation is transmitted to external systems. It is characterized by being able to sell electricity.

According to the second aspect of the present invention, when the surplus of the power obtained by the photovoltaic power generation cannot be sold to an external system, the surplus of the power obtained by the photovoltaic power generation is replaced by
It is characterized in that a storage battery for a house and / or a storage battery for a vehicle of an electric vehicle are charged.

[0007]

According to the first aspect of the present invention, the power obtained by solar power generation, the midnight power of the external system,
Among the general power of the external system, the lowest cost power is used preferentially, so that the cost can be reduced and the surplus of the power obtained by solar power generation is Since power can be transmitted to the grid and sold, significant cost reductions can be realized.

According to the invention described in claim 2, according to claim 1
In addition to the effects of the invention, if the surplus of the power obtained by the solar power generation cannot be sold to an external system for any reason, the surplus of the power obtained by the solar power generation It is used for charging a storage battery for a vehicle and / or a storage battery for a vehicle of an electric vehicle, so that waste of power can be eliminated and cost can be further reduced.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 schematically shows a household power supply system according to the present invention. In FIG. 1, reference numeral 1 denotes an external system power wiring transmitted from a power company.

On the house side, a switchboard 2 connected to the power wiring 1, various house electrical equipments 3 connected to the switchboard 2 by the indoor wiring 8, and overcharging and overcharging also connected to the switchboard 2. A charge / discharge device 4 for preventing discharge, a residential storage battery 5 connected to the charge / discharge device 4, a discharger 6 connected to the indoor wiring 8, a controller 7, a solar power generation device 9, Is provided.

As shown in FIG. 1, the controller 7 is connected to the indoor wiring 8, the respective residential electrical equipment 3, the charging / discharging device 4, the discharging device 6, and the solar power generation device 9. .

The discharger 6 is a discharge connector 10 installed outside the house and connected to an electric vehicle 20 described later.
It has.

The photovoltaic power generation device 9 is installed on the roof of a house mainly using a photovoltaic cell plate, and uses the electric power obtained by the photovoltaic power generation through the indoor wiring 8 for the residential electric equipment 3 and the charging / discharging device. 4, residential storage battery 5, discharger 6, and controller 7 can be supplied.

The electric vehicle 20 includes a vehicle storage battery 21 and an inlet 22 connected to the discharge connector 10 to enable charging of the vehicle storage battery 21.

The above-mentioned controller 7 controls the power obtained by the photovoltaic power generation device 9 (hereinafter referred to as the power obtained by photovoltaic power generation), the late-night power of the external system 1 and the general power of the external system 1. Are controlled so that low-cost electric power can be preferentially supplied to the residential electrical equipment 3 and the residential storage battery 5 and / or the vehicle storage battery 21 of the electric vehicle 20.

Here, the power rate of the external system 1 is generally lower in the case of late-night power transmitted from midnight to early morning than in general power transmitted from daytime to night, and the cost is lower. The power obtained by photovoltaic power generation only costs the initial cost of the photovoltaic power generation device 9 and the power rate is free and lower in cost than late-night power. Description will be made in the order of power obtained by solar power generation, midnight power, and general power.

The controller 7 controls the surplus of the electric power obtained by the photovoltaic power generation to be transmitted to the external system 1 so that the electric power can be sold.

Next, a basic configuration of power supply control by the controller 7 will be described with reference to FIG.

A switch 30 is provided in the output side circuit of the photovoltaic power generator 9.

The switch 30 is provided with a first diode 31 for preventing backflow of current from the load side, and for preventing backflow of a current in a direction opposite to the first diode 31 for preventing backflow. A second diode 32 and a contact 33 provided between the first and second diodes 31, 32 for preventing backflow are provided.

The output side of the first diode 31 is DC / A
An inverter 34 for performing C conversion is connected, and the output side of the inverter 34 is a residential electric facility 3, a residential storage battery 5, a discharger 6, a late-night power rate meter 35 of the external system 1, and a general power rate. It is connected to a total of 36.

The late-night power meter 35 and the general power meter 36 are both connected to the residential electrical equipment 3 and the discharger 6.

The discharger 6 includes a first inverter 37 for performing AC / AC conversion and a second inverter 3 for performing AC / DC conversion.
8 are connected in series, and the first inverter 37 is connected to the discharge connector 10.

The second inverter 38 is connected to the input side of the second diode 32 of the switch 30, and the output side of the second diode 32 is connected to the residential storage battery 5.

The inlet 22 of the electric vehicle 20 has an AC /
Vehicle battery 21 via inverter 39 for performing DC conversion
Connected to

Each of the discharge connector 10 and the inlet 22 is provided with a coil (not shown) constituting a transformer. When the discharge connector 10 and the inlet 22 are connected, the first inverter 37 of the discharger 6 is connected to the electric vehicle by magnetic coupling of these coils. The power is supplied to the 20 inverters 39.

When the discharge connector 10 and the inlet 22 are not connected, the first inverter 3 of the discharger 6
7 is converted into a DC current by a second inverter 38 and supplied to the residential storage battery 5 via the second diode 32 of the switch 30.

In this embodiment, the photovoltaic power generation device 9 includes a power generation control device 40 that controls the power generation by, for example, covering a solar cell plate.

The controller 7 includes a late-night electricity rate meter 35
And the respective power detection signals of the general wattmeter 36, the detection signal of the photovoltaic power generation detection sensor 41 provided in the photovoltaic power generation device 9, the power generation signal of the photovoltaic power generation device 9 from the inverter 34,
A load detection signal of a load sensor 42 provided in the residential storage battery 5, a load detection signal from a load sensor (not shown) of the electric home equipment 3, and a first inverter 37 of the discharger 30.
, A load detection signal from a load sensor (not shown) of the vehicle battery 21 of the electric vehicle 20 is input.

The controller 7 sends a control signal to the switch 30 or the like based on each of the detection signals, and loads the power in the order of the power obtained by the photovoltaic power generation, the midnight power, and the general power. In addition to supplying to the electric equipment for home 3, the storage battery 5 for the house, and the storage battery 21 for the vehicle of the electric vehicle 20, when the power obtained by the solar power generation exceeds the load demand, the surplus power is supplied to the midnight power. Total 3
5, power is transmitted to the external system 1 through the general power meter 36 to sell power, and in some cases, the power generation control device 40 is operated to appropriately suppress the power generation of the solar power generation device 9. .

Next, referring to the control flowchart shown in FIG.
Will be described.

First, in the figure, it is determined whether or not the photovoltaic power generation device 9 can generate power by sunlight based on the detection signal of the photovoltaic power generation detection sensor 41 (step 1).

If (YES) is determined in step 1, the electric power generated by the photovoltaic power generator 9 is detected by a load sensor (not shown) based on the electric power signal input from the inverter 34. It is determined whether the power load is greater than the combined power load of the vehicle and the vehicle storage battery 21, that is, whether a surplus is obtained (step 2).

If the power obtained by the photovoltaic power generation is larger than the used power and (YES) is determined in step 2, the power sales price is determined based on the power sale unit price, the midnight power unit price, the solar power unit price, and the like. It is determined whether or not the power can be sold by determining whether or not the stored power price profit of the storage battery 5 for the house is higher (step 3). If (YES) is determined in the step 3, the inverter 34 shown in FIG. The / AC converted photovoltaic power is transmitted to the external system 1 through the power supply route indicated by the arrow A in the figure to sell the power (step 4).

The power supply contract with the power company has expired, or the external system has failed due to a disaster or the like, and it is determined in step 3 (NO)
Is determined, the surplus power is supplied to the residential storage battery 5 through the power supply route indicated by the arrow B in FIG. 2 to be charged and stored (step 5).

The state of charge of the residential storage battery 5 is detected by the load sensor 42, and it is determined whether or not the residential storage battery 5 is fully charged based on the detected value (step 6).

If (YES) is determined in step 6,
An operation signal is sent to the power generation control device 40 to
0 is operated to suppress the power generation of the photovoltaic power generator 9 (step 7), and conversely, if (NO) is determined in step 6, the battery is charged until the residential storage battery 5 is fully charged (step 8). .

If the power obtained by the photovoltaic power generation has no surplus until the power is sold, and if (NO) is determined in step 2, the photovoltaic power DC / AC converted by the inverter 34 shown in FIG. The generated power is supplied to the residential electric equipment 3 through a power supply route indicated by an arrow C in the same figure, and is supplied to the vehicle storage battery 21 of the electric vehicle 20 when the discharge connector 10 and the inlet 22 are connected. To charge the vehicle storage battery 21 (step 9).

When the power supplied to the load such as the residential electric equipment 3 and the vehicle storage battery 21 is insufficient, it is determined whether or not the stored power remains in the residential storage battery 5 (step 10). If YES is determined, the contact 33 of the switch 30 shown in FIG. 2 is turned on, and the power shortage is performed by the power supply from the storage battery 5 through the power supply route indicated by the arrow D in FIG. 2 (step 11). Conversely, if (NO) is determined in step 10 and no stored power remains in the storage battery 5, the power shortage is supplemented by the supply of general power through the power supply route indicated by the arrow E in FIG. (Step 12).

On the other hand, power generation by the photovoltaic power generator 9 is not possible due to nighttime or rainy weather, etc.
If O) is determined, it is determined whether or not it is in the late-night time zone in which late-night power is supplied (step 13). If (YES) is determined in step 13 in the late-night time zone, it is indicated by arrow F in FIG. Midnight power is supplied to loads such as the residential electrical equipment 3 and the vehicle storage battery 21 through the power supply route (step 14).

Subsequently, it is determined whether or not this late-night electric power is sufficiently larger than the electric power supplied to the residential electric equipment 3 and the vehicle storage battery 21 (step 15).
ES), the surplus of the late-night power AC / AC converted by the first inverter 37 of the discharger 6 shown in FIG.
Is supplied to the residential storage battery 5 through a power supply route indicated by an arrow G passing through the second diode 32 to be charged and stored (step 16).

The state of charge of the residential storage battery 5 is detected by the load sensor 42, and based on the detected value, it is determined whether or not the residential storage battery 5 is fully charged (step 1).
7). If (YES) is determined in step 17, the charging of the residential storage battery 5 is stopped (step 18). Conversely, if (NO) is determined in step 17, the residential storage battery 5 is not charged.
Is charged until the battery is fully charged (step 19).

Residential electrical equipment 3 and vehicle storage battery 21
Etc., the demand for electricity at night is large,
If (NO) is determined in step (3), the contact 33 of the switch 30 shown in FIG.
1 (step 20).

When the power generation by the photovoltaic power generator 9 is not possible except during the midnight hours, that is, the power is not obtained by the photovoltaic power generation due to rain or the like during the day. Is determined, it is determined whether or not the stored power of the storage battery 5 for the house remains (step 21).

If (YES) is determined in the step 21, the contact 33 of the switch 30 shown in FIG. 2 is turned on, and the stored power of the storage battery 5 for the house is stored in the power supply route indicated by the arrow D in FIG. To the loads such as the electrical equipment 3 and the vehicle storage battery 21 (step 22).

Subsequently, it is determined whether or not the stored power of the storage battery 5 for the house has become insufficient due to the power supply (step 23).
If S) is determined, the shortage is supplemented with general power in the power supply route indicated by the arrow E in FIG. 2 (step 24),
Conversely, the stored power is sufficient, and in step 23 (NO)
Is determined, the process returns to step 22.

If the stored power of the storage battery 5 for the house is originally in a shortage state and (NO) is determined in the step 21, the general power is transferred to the house by the power supply route indicated by the arrow E in FIG. Electrical equipment 3 and vehicle storage battery 2
1 (step 25).

The power supply routes A to G based on the above control logic are shown in a pattern diagram in FIG.

As described above, according to the present embodiment, the power obtained by the solar power generation with the lowest cost is given the highest priority, and thereafter, the power is applied to the load in the order of the late-night power of the external system 1 and the general power of the external system 1. Since power can be supplied, the cost can be reduced, and the surplus of the power obtained by photovoltaic power generation can be sent to the external system 1 for sale, thereby achieving a significant cost reduction. can do.

When the surplus of the power obtained by the photovoltaic power generation cannot be sold to the external system 1 for some reason, the surplus of the power obtained by the photovoltaic power generation is transferred to the house. It is used for charging the storage battery 5 or the vehicle storage battery 21 of the electric vehicle 20, so that waste of power can be eliminated and cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing an embodiment of a household power supply system according to the present invention.

FIG. 2 is a block circuit diagram showing a basic configuration of power supply control of the embodiment.

FIG. 3 is a control flowchart of the embodiment.

FIG. 4 is an exemplary diagram showing a pattern of a power supply route according to the power supply control of the embodiment;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power wiring (external system) 3 Residential electric equipment 5 Residential storage battery 7 Controller 9 Solar power generation device 20 Electric vehicle 21 Vehicle storage battery

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Junichi Kasai Nissan Motor Co., Ltd., 2nd Takaracho, Kanagawa-ku, Yokohama, Kanagawa (72) Inventor Hideaki Horie 2nd Takaracho, Kanagawa-ku, Yokohama, Kanagawa 72) Inventor Hirokazu Hirano Nissan Motor Co., Ltd., 2 Takara-cho, Kanagawa-ku, Yokohama-shi, Kanagawa

Claims (2)

[Claims] 1. A method of comparing the cost of electric power obtained by photovoltaic power generation, the cost of late-night electric power of an external system, and the cost of general electric power of an external system, and preferentially giving low-cost electric power to residential electrical equipment and Household storage battery and / or electric vehicle vehicle storage battery, and surplus power obtained by photovoltaic power generation is transmitted to an external system for power sale. Power supply system. 2. If the surplus of the power obtained by the photovoltaic power generation cannot be sold to an external system, the surplus of the power obtained by the photovoltaic power generation is stored in a storage battery for a house and / or a vehicle storage battery for an electric vehicle. The home power supply system according to claim 1, wherein the power is supplied to the home power supply system.