JP2000314752A - Power monitoring system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To be able to visually monitor the instantaneous value and integrated value of DC power generation and AC power consumption at home in real time and visually. SOLUTION: A residential distribution board 60 with a power monitoring function for obtaining an instantaneous value and an integrated value of DC power generated by a solar cell module 10 and an instantaneous value and an integrated value of AC power consumption supplied from a commercial AC power line. And a power monitor 80 for displaying the instantaneous value and the integrated value in real time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention monitors the amount of DC power generated by a photovoltaic power generator installed in a house or the like and the amount of AC power consumed in a house or the like. The present invention relates to a power monitoring system in which an energy consumer voluntarily controls a load of an electric device or the like so that an indirect load control for energy saving is promoted.

[0002]

2. Description of the Related Art In recent years, attention has been paid to energy saving as one means for solving environmental problems, and considerable efforts have been made in national policies. As a result, considerable energy saving has been achieved in the industrial and transportation sectors. .

[0003] However, in the consumer sector, power consumption tends to increase year by year, and in particular, power consumption in commercial buildings and houses has increased significantly. In order to avoid investment, energy conservation measures are being demanded.

In response to such environmental and energy problems,
Attention has been focused on the introduction of a photovoltaic power generation system into a home as a specific approach that can be taken in a general home.

In this system, as shown in FIG. 4, a solar cell module 201 is mounted on a gantry on a roof of a house, and DC power is generated there by sunlight. The power is supplied to an inverter 204 via a switch 203 and converted into AC power there.
Further, via the protection device 205 and the generated power meter 206,
The residential distribution board 207 is linked to a conventional AC commercial power supply. The AC power supplied from the commercial power cable 208 is supplied to the purchased power meter 209 and the AC-side switch 210.
Is input to the distribution board for house 207 via the. The power generated by the photovoltaic power generation, domestic lighting equipment, air conditioners,
It is also supplied to electric equipment such as a television set, but if there is excess, it may be purchased by a power supply company. The power sale amount at this time is measured by the power sale electricity meter 211.

However, in the system of FIG. 4, devices such as a solar cell module 201, a purchased power meter 209, a sold power meter 211, a generated power meter 206, a distribution board 207 for a house, and many other devices are used. Needed and costly. Regarding the introduction cost of the current photovoltaic power generation system, it is said that the amount of power generation reaches 3,000,000 yen to 4,000,000 yen for a 3KW type, which is a heavy burden on consumers.

In addition, the measurement of the amount of DC power generated by the photovoltaic power generation system and the amount of AC power consumption at home is performed on a monthly basis in order to collect fees, so that consumers are conscious of energy consumption. Never before.

[0008]

As described above, due to the high cost of the photovoltaic power generation system and the low awareness of energy saving, the photovoltaic power generation system has not spread, and it is difficult to practice energy saving at home. Although difficult, energy savings can be further promoted if energy consumers themselves implement indirect load control to control power consumption loads.

Therefore, the measurement (monitoring) of the electric energy is expected to be promising. 1 when an average home photovoltaic system (3KW) is installed in an average detached house
Daily DC power generation (□) and AC power consumption (×)
Is shown in FIG. As is clear from this figure, in each of the winter, middle and summer periods, the AC power consumption is concentrated almost in the morning and night, and the DC power generation is concentrated in the daytime.

However, such household power monitoring for grasping the absolute values of the DC power consumption and the AC power consumption and the correlation between the two in real time has not been established as a system.

The only opportunity for the consumer to confirm the amount of AC power consumption is when checking the bill from the power supply company once a month, and visually grasp the DC power generation and AC power consumption in real time. It is difficult to do.

The present invention has been made in view of the above points, and an object of the present invention is to enable a consumer to grasp the amount of DC power generation and the amount of AC power consumption in real time and visually. Accordingly, it is an object of the present invention to provide a power monitoring system which facilitates the above-described indirect load control and promotes energy saving.

[0013]

According to a first aspect of the present invention, there is provided a power monitoring system comprising: an instantaneous value and an integrated value of DC power generated by a photovoltaic power generation means; and an instantaneous value of AC power consumption. A distribution board provided with a means for obtaining an integrated value, and a power monitoring device for displaying each instantaneous value and the integrated value obtained by the distribution board in real time are provided.

[0014] In a second aspect based on the first aspect, the distribution board includes means for transmitting the integrated value data to a communication line.

In a third aspect based on the second aspect, the distribution board includes an AC power consumption detection unit, an AC power signal detected by the AC power detection unit, and a DC power signal detected by the DC power generation detection unit. An input conversion IFU that captures a power signal, a control device that captures a signal from the input conversion IFU, sends the instantaneous value and the integrated value display signal to the power monitoring device, and creates a transmission data signal of the integrated value; And a modem for periodically transmitting the transmission data of the integrated value created by the control device to the communication line.

[0016]

1 is a block diagram of an in-house power monitoring system according to an embodiment of the present invention, FIG. 2 is a system diagram of the in-house power monitoring system, and FIG. 3 is installed in a plurality of detached houses A1 to An. 1 is a system diagram of the entire power monitoring system.

1 to 3, reference numeral 10 denotes a detached house A.
1 to An solar cell module installed on a roof or the like, and its generated DC output is collected in a junction box 20 having a switch (not shown), and then DC generated power detection including a DC power meter 31 is performed. The power is individually transmitted to the collective inverter 40 via the unit 30, converted into AC power there, and transmitted to the power load 50.

The DC power meter 31 has, for example, a rated voltage of 20.
0V, rated current 30A, power detection range is 0-6K
W and its operating voltage range is up to 350V. In the DC power meter 31, the instantaneous value of the DC power is detected and measured, and the external output is frequency-converted into a pulse signal. The accuracy is, for example, a voltage of 150 V, 250 V, 35
At 0 V, ± 2.0% at a current of 1/5 or more of the rated current.

Reference numeral 60 denotes a residential power distribution panel having a power monitoring function. As shown in detail in FIG. 1, the distribution board 60 is connected to a single-phase three-wire AC power line 70 in addition to a normal branching unit (not shown) that distributes power to various home electric appliances and home outlets. An AC power consumption detection unit 61 for detecting the consumption of the supplied AC power, an instantaneous value signal of the power consumption detected by the AC power consumption detection unit 61, and an instantaneous value of the DC power generation detected by the DC power meter 31 Input conversion IFU that takes in signals and calculates each integrated value
(Interface unit) 62, its input conversion IF
A control device (CP) which takes in the output signal of U62 and temporarily stores it in a memory, sends a display signal to a power monitoring device 80 including a personal computer or other display device, processes transmission data and sends it to an analog modem 63
PLC with U: Programmable Logic Controller)
64, a line call detection / switching unit 65 connected to the communication line 90, and various power supply circuits (not shown) for each circuit and for backup.

In the AC power detecting unit 61 shown in FIG. 1, the voltage detecting unit 61a is connected to the N line of the AC power line 70 and L2
The voltage between the lines (100V) is detected, and the current detection unit 61b detects the currents of the L1 line and the L2 line of the power line 70 through the external current transformer 7
The current signals (for example, pulse signals) from 1, 72 are taken in and detected. The current signals detected by the current transformers 71 and 72 are added by an adder 61c. Then, the voltage detector 6
An instantaneous value of power consumption is obtained by calculating the voltage value detected in 1a and the current value added in the adding unit 61c in the calculating unit 61d. The detection range of the instantaneous power value is, for example, 0 to 20K.
The accuracy is set to ± 5% in W. The detected instantaneous value signal of the electric power is sent to the VF converter 61e, where it is converted into a frequency signal (pulse signal). This VF converter 61e
Is taken into a photocoupler 61f for insulation, and is output therefrom to the input conversion IFU 62 described above.

The AC power line 70 and the communication line 90 are
As shown in FIG. 2, it is introduced into the relay pole 100 and is buried underground through a meter box 110 equipped with a general AC wattmeter, a drop-in switch, a communication line protector, etc., and is drawn into the house. . The DC power generated by the solar cell module 10 is transmitted to the collective inverter 40 via the DC power line 120 passing through the meter box 110 and the relay pole 100.

In the power monitoring system of the present invention, a frequency signal (pulse signal) indicating the instantaneous value (KW) of the DC power detected and measured by the DC power meter 31 and the AC power consumption detection unit 61 detect and measure. Signal (pulse signal) indicating the instantaneous value (KW) of the consumed AC power
Is taken into the input conversion IFU 62, where it is sampled, for example, every 4 seconds, and the average power per hour in the past,
That is, the integrated value (KWh) is calculated.

The instantaneous value of the DC power and the integrated value per hour in the past, and the instantaneous value of the AC power consumption and the integrated value per hour in the past are taken into the control device 64, and the integrated value is It is temporarily stored in a memory and processed into transmission data.

The power monitoring device 80 displays the instantaneous value and the integrated value sent from the control device 64. In this display mode, for example, in the case of a digital numerical display, the instantaneous value is displayed in real time as "XXKW" and the integrated value is displayed as "XXKWh" in real time. Are sequentially updated and displayed as “○ month portion ○ KWh”, but it is also possible to separately or simultaneously display an analog graph.

The transmission data processed by the control device 64 is transmitted to the analog modem 63 and transmitted from the communication line 90 via the line communication detection / switching device 65 to the energy management center 130 as shown in FIG. The data for transmission is, for example, 50 samples per day. That is, the integrated value of DC power generation and AC power consumption every hour (total of 48 samples) and the integrated value of DC power generation and AC power consumption per day (2 samples). The format is, for example, "date + time +
Power data (four digits) + user ID ". Modem 63
Is transmitted from the control device 64 after transmission.
Is erased from the memory.

As one example, the communication line 90 connecting the modem 63 is an analog public telephone line or an ISDN line (via TA), and the line selection signal system is DP (1
0, 20 pps) Signaling method, data transmission method is toll-free scheduled transmission method, data signal method is V.32 QMA method, and data signal speed is 14.4 kbps (maximum).

As described above, the integrated data of the DC power generation and AC power consumption of each home is stored in the energy management center 130.
Automatically at regular intervals, the statistics are collected at the energy management center 130, and if the contents are developed on the Internet etc., each consumer home can check the Web screen to check the DC power generation and AC power consumption. It is easy to compare one's own home with other homes and ordinary homes, and it is possible to promote indirect load control for self-load control and energy saving. Note that, as shown in FIG.
The TV station 140 may notify each home via the CATV line 150.

As described above, the power monitoring system of the present invention uses the power monitoring device 80 to monitor the instantaneous and integrated values of the DC power generated by the solar cell module 10 and the AC power consumption of the entire house as a user function. It has a power monitoring function to display and an automatic alarm function to automatically alarm the integrated value data of DC power generation and AC power consumption from the modem 63 to the energy management center 130 at regular intervals.

The system functions include, in addition to the functions described above, a power failure backup function for maintaining a sampling value of DC generated power and accumulation of information during a commercial AC power failure (including an instantaneous interruption) and an AC commercial power failure. Automatic power generation at power failure recovery, which automatically reports the integrated value data of DC power generation and AC power consumption that could not be transmitted at the time of power failure recovery, construction and adjustment, daily power data upload, power recovery after power failure, etc. Clock adjustment function to synchronize time
It is desirable to provide a transmission data collation function or the like that can check whether the data transferred to the energy management center 130 is correct.

In the embodiment described above, the integrated value of the power is calculated by the input conversion IFU 62. However, the input conversion IFU 62 may simply calculate an interface and calculate by the control device 64. Although the DC power detection unit 30 and the AC power consumption detection unit 61 output only a signal of the instantaneous value of the power, a signal of the power integration value of the past hour may be output together with the signal. . In this case, the input conversion IFU 62 and the control device 64
It is not necessary to calculate the integrated value by. In the above description, the DC power is not directly consumed in the home, but is sent to the collective inverter 40. However, as described in the conventional example, the inverter is provided in the home and converted into AC there. Of course, it is possible to take it into the distribution board at home, and it is also possible to sell power.

[0031]

As described above, according to the present invention, the instantaneous value and integrated value of DC power generation and AC power consumption can be grasped by a power monitoring device in real time and visually. Since it can be developed so that it can be compared with that of a home or a general home, there is an advantage that it is easy to realize indirect load control based on the consumer's awareness, and it is possible to promote energy saving.

[Brief description of the drawings]

FIG. 1 is a block diagram of a home power monitoring system according to an embodiment of the present invention.

FIG. 2 is a system diagram of a power monitoring system in a house.

FIG. 3 is an overall system diagram of the power monitoring system.

FIG. 4 is an explanatory diagram of a conventional residential solar power generation system.

FIG. 5 is a characteristic diagram showing a temporal pattern of a power generation amount of a solar power generation system and a power consumption amount of a single-family house.

[Explanation of symbols]

10: solar cell module, 20: junction box, 30: DC power detection unit, 31: DC power meter, 40: batch inverter, 50: power load, 60: residential distribution board with power monitoring function, 61: AC power consumption detection unit, 61a: voltage detection unit, 61b: current detection unit, 61
c: adder, 61d: calculator, 61e: VF converter,
61f: photo coupler, 62: input conversion IFU, 63:
Analog modem, 64: control device (PLC), 65: line communication detection / switching unit, 70: single-phase three-wire AC power line,
80: Power monitoring device, 90: Communication line, 100: Relay pole, 110: Meter box, 120: DC power line, 130: Energy management center, 140: CATV
Office, 150: CATV line.

Continued on the front page (72) Inventor Toshio Matsushima 3-19-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Japan Telegraph and Telephone Co., Ltd. (72) Inventor Taketaka Obama 3-192-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Japan Within Telegraph and Telephone Co., Ltd. (72) Inventor Kazuyuki Yamamoto 1048 Kadoma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Works, Ltd. (72) Inventor Kazuhisa Takahashi 1048 Kadoma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd.

Claims (3)

[Claims] 1. A distribution board provided with means for obtaining an instantaneous value and an integrated value of DC power generated by a photovoltaic power generation means and an instantaneous value and an integrated value of AC power consumption, and a distribution board obtained by the distribution board. A power monitoring system comprising: a power monitoring device that displays each instantaneous value and an integrated value in real time. 2. The power monitoring system according to claim 1, wherein the distribution board includes means for transmitting the integrated value data to a communication line. 3. An input conversion IFU for receiving an AC power consumption detection unit, an AC power signal detected by the AC power detection unit, and a DC power signal detected by the DC power generation detection unit. A control unit that takes in a signal from the conversion IFU, sends a signal for displaying the instantaneous value and the integrated value to the power monitoring device, and creates a data signal for transmitting the integrated value; and an integrated value created by the control device. 3. The power monitoring system according to claim 2, further comprising a modem for transmitting the transmission data to the communication line on a regular basis.