JP2018046662A - Collective power reception/transformation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an operation form in which fuel battery power generation devices are installed in specific dwelling units, some of a plurality of dwelling units, and effects of the power generation devices can be effectively caused and economical merit of a business operator supplying low-voltage power to each dwelling unit can be held, in a collective power reception/transformation system that collectively receives high-voltage power, steps down the power into low-voltage power and then supplies the power to the plurality of dwelling units.SOLUTION: The operation form is configured so that the power generation device regularly performs rated operation and surplus power which has not been used by electric loads of specific dwelling units, of generated power during rated operation is interchanged through a first distribution network with the other dwelling units. The number of the specific dwelling units and rated output are set so that the total of the generated power during rated operation of the power generation device does not surpass a predicted minimum value of total consumed power by the plurality of dwelling units.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a collective power receiving and transforming system that collectively receives high voltage power supplied from a commercial power supply using a power receiving / transforming facility, steps down the voltage to low voltage power, and then separately supplies the power load to a plurality of dwelling units such as an apartment house.

  In recent years, businesses such as power aggregators that effectively bundle energy demands of consumers and effectively provide energy management services have signed high-voltage power receiving contracts with power companies at multiple dwelling units such as apartment buildings, Power supply of the collective high-voltage power receiving system that lowers the high-voltage power (for example, 6600V) supplied from the system power source to low-voltage power (for example, 200V) at the power receiving / transforming facility of the operator and supplies it to each dwelling unit contracted with the operator The form is spreading (see, for example, Patent Document 1 below).

  Here, in the high-voltage contract and low-voltage contract with the electric power company, the unit price of electricity charges is set lower in the high-voltage contract than in the low-voltage contract. By setting the unit price of the electricity charge for the low-voltage contract of the company to be lower than the unit price of the electricity charge for the low-voltage contract with the power company, but higher than the unit price of the electricity charge for the high-voltage contract with the power company Economic benefits for both consumers and consumers of each unit.

  On the other hand, in a plurality of dwelling units such as apartment buildings, a power generation system configured to install a fuel cell power generation device in each dwelling unit, and to supply the power generated by each power generation device and the power from the commercial power supply to the power load of each dwelling The dwelling units equipped with the power generation devices are interconnected by a power line network, and the surplus power exceeding the individual power load of the power generation devices in each dwelling unit is caused to flow backward to the power line network connecting the dwelling units. Thus, attempts have been made to increase the power self-sufficiency rate in a plurality of dwelling units by accommodating the power load of other dwelling units (see, for example, Patent Documents 2 and 3 below).

  However, since the power generation system or power generation control system disclosed in Patent Literatures 2 and 3 functions as a combined heat and power system using waste heat from the fuel cell, the power generation output of the fuel cell is the power demand or heat of each dwelling unit. Based on the electric main operation or the heat main operation to follow the demand, the electric power self-sufficiency rate in the plurality of dwelling units is further controlled.

JP 2013-117484 A JP 2007-128785 A Japanese Patent No. 5842069

A fuel cell power generator that uses city gas (natural gas) as fuel, reforms the fuel to produce hydrogen, and supplies the hydrogen to the fuel electrode of the fuel cell to generate power. It is known that there is no transmission / distribution loss, high power generation efficiency, and large energy saving effect and CO ₂ saving effect. Therefore, if the surplus power of such a distributed generator can be effectively used, the energy saving effect and CO ₂ saving effect in society as a whole are expected to increase, and furthermore, the power demand peak can be supplemented with surplus power. Peak cut effect is also expected.

  Therefore, in order to make the best use of the above-described effects of the fuel cell power generator, it is preferable to perform rated operation with the highest power generation efficiency. However, for example, when a household fuel cell power generator with a rated output of 700 W is constantly operated at rated power, the average power load of a general household of 3 to 4 family members is between about 200 W and about 800 W per day. Therefore, surplus power is generated reliably. For this reason, in the power generation systems disclosed in Patent Documents 2 and 3, when the fuel cell power generator is always rated at all units, the surplus power is reversed outside the area of the plurality of dwelling units, that is, to the power distribution network of the commercial power supply. It will be necessary to make it flow and buy it from commercial power transmission and distribution companies. However, the purchase price from the user of the fuel cell power generation device is kept low so that the power transmission / distribution company does not cause a loss due to the purchase of surplus power of the fuel cell power generation device. For this reason, the user of the fuel cell power generator does not have a cost merit for the surplus power that flows backward out of the area. Therefore, in the power generation systems disclosed in Patent Documents 2 and 3, the power generation output is controlled without performing rated operation so as not to generate surplus power that causes reverse power flow outside the region.

  On the other hand, as disclosed in Patent Documents 2 and 3, a fuel cell power generator is installed in each of a plurality of dwelling units adopting the above-described collective high-voltage power receiving power supply mode, When operation control is performed so as to increase the power self-sufficiency rate, the business merits of the business operator that supplies the power are significantly hindered. In other words, the operator only supplies the deficient power to each dwelling unit with the low-voltage power that has been stepped down by the power receiving / transforming equipment only during the period when the power demand exceeds the rated output of the fuel cell power generator. The economic merit of installing and operating the facilities is impaired.

  The present invention has been made in view of the above-mentioned problems, and its purpose is to collect high-voltage power supplied from a commercial power supply using a power receiving / transforming facility, and reduce the voltage to low-voltage power. In a collective power receiving and transformation system that supplies power to each unit's power load separately, such as a house, there is an economic merit for businesses that install fuel cell power generators in some of the units and supply low-voltage power to each unit. In addition, it is an object of the present invention to provide an operation mode of a fuel cell power generator that can effectively exhibit the effects of the fuel cell power generator.

The collective power receiving / transforming system according to the present invention includes a first power receiving / transforming facility, and a power management company receives the high-voltage power supplied from a commercial power supply in a lump using the first power receiving / transforming facility. After stepping down to low-voltage power, the first low-voltage power is supplied separately to the power loads of a plurality of dwelling units existing in the area managed by the power management company via the first distribution network laid in the area. A collective power receiving / transforming system
One or more specific dwelling units that are a part of the plurality of dwelling units in the area consume fuel supplied from the outside, and have the same voltage, frequency, and electric power as the first low-voltage power. Each has a distributed generator to generate electricity,
Each of the distributed power generators is configured to include a fuel cell, and is set to always operate at a rated value except for a predetermined case in which fuel supply from the outside stops, and the generated power of the distributed power generator Is configured to be able to supply power to the power load of the specific dwelling unit in conjunction with the first low-voltage power, and further, out of the generated power during rated operation of the distributed power generator, of the specific dwelling unit Each of the surplus power that was not consumed by the power load is configured to flow backward to the first distribution network and be accommodated in the power load of the other dwelling units in the area,
The number of units of the specific unit so that the total generated power at the rated operation of the distributed generator installed in the specific unit does not exceed the predicted minimum value of the total power consumption of a plurality of units existing in the area. The first characteristic is that the generated power at the rated operation is set.

According to the collective power receiving and transforming system of the first feature described above, since the distributed power generation device (fuel cell power generation device) installed in the specific dwelling unit is always rated and operated, the power generation device has the energy saving effect, the CO ₂ effect, and Thus, the peak cut effect can be utilized to the maximum, and the social contribution per unit of the fuel cell power generator can be maximized. Furthermore, since the total power generated by the distributed generator does not exceed the predicted minimum power consumption of multiple units, all of the surplus power can be consumed by all the power loads of the units that receive the surplus power. You can avoid the situation. In addition, since the average value of the power generated by the distributed generators consumed per unit of a plurality of dwelling units is predicted to be less than the minimum value of the average power load per unit, It is always covered by the first low-voltage power that has been stepped down by the first power receiving / transforming facility. Therefore, the economic merit of supplying electric power to a plurality of dwelling units using a collective power receiving / transforming system is also ensured for the power management company. In addition, the transformer capacity of the first power receiving / transforming equipment can reduce the total amount of power generated by the distributed power generating equipment as compared to the case where no distributed power generating equipment is provided. There is also a merit that costs for introduction and operation can be reduced.

  Furthermore, in the collective power receiving and transforming system according to the first feature, it is preferable that the fuel cell included in the distributed power generation device is a solid oxide fuel cell.

As a fuel cell power generator for home use installed in a dwelling unit, one using a polymer electrolyte fuel cell (PEFC) and one using a solid oxide fuel cell (SOFC) are in widespread use. PEFC has been developed and commercialized as a home fuel cell earlier than SOFC because it has a low operating temperature of about 80 ° C, so it is easy to start and stop and takes less time to operate. . Since SOFC has higher power generation efficiency than PEFC, the above-mentioned energy saving effect, CO ₂ saving effect, peak cut effect and the like are further improved. Moreover, since SOFC uses ceramics as an electrolyte, SOFC has an operating temperature as high as about 700 ° C. or higher, and is not easily started and stopped. However, this disadvantage does not pose any problem in the always rated operation in the first feature, and the power generation efficiency can be maximized. That is, SOFC can be said to be a fuel cell system more suitable than the PEFC for the collective power receiving and transforming system of the first feature. Although PEFC is generally considered to have lower power generation efficiency than SOFC, it can naturally be used as a distributed power generator for the collective power receiving and transforming system of the first feature. The fuel cell used in the power generation apparatus is not limited to a specific type.

  Furthermore, in the collective power receiving and transforming system according to the first feature, it is preferable that the predicted minimum value is a value obtained by multiplying 200 W by the total number of the plurality of dwelling units.

  As a plurality of dwelling units in the above area, for example, assuming a family apartment with about 3 to 4 family members, the minimum value of the average power load of a general household with 3 to 4 family members is about 200 W. Assuming that the predicted minimum value is 200 W multiplied by the total number of the plurality of dwelling units, the “total power generated during rated operation of the distributed generator is the sum of the plurality of dwelling units present in the region” in the first feature. The condition that the predicted minimum value of total power consumption is not exceeded is satisfied.

  Furthermore, the collective power receiving / transforming system according to the present invention further includes a second power receiving / transforming facility in addition to the first feature, and uses the second power receiving / transforming facility to receive high-voltage power supplied from the commercial power supply. After receiving power and stepping down to a second low-voltage power, supplying the second low-voltage power to a power load of a shared facility shared by residents of the plurality of dwelling units via a second distribution network is second. It is characterized by.

  According to the collective power receiving / transforming system of the second feature, it is possible to supply the second low-voltage power to the power load of the shared facility, and further includes the second power receiving / transforming facility separately from the first power receiving / transforming facility. Thus, the supply of the second low-voltage power is not limited to the power management company that supplies the first low-voltage power, and other power management companies can also supply the second low-voltage power.

  Furthermore, in addition to any of the above-described features, the collective power receiving / transforming system according to the present invention has an end portion on the first power receiving / transforming equipment side of the first power distribution network from the first power receiving / transforming equipment to the first power distribution. The distributed power generation is performed based on an output signal indicating a measured value or the measured value, by measuring the current, power, or the electric energy of the first low-voltage power supplied to the network for each predetermined unit period. A measuring instrument that outputs a control signal for controlling the operation of the apparatus, and at least one of the measuring instrument and the distributed generator is connected by a signal line capable of transmitting the output signal or the control signal; In accordance with the output signal or the control signal, at least one of the distributed generators is configured to stop the rated operation and reduce the output power from the rated output, and to connect the first low-voltage power. At least one of the blocking processes By performing the processing, to perform the control for reducing the surplus power and the third feature.

  According to the collective power receiving and transforming system according to the third feature, the “total power generated during rated operation of the distributed power generator is the sum of the plurality of dwelling units existing in the region” Even if the situation that the predicted total value of total power consumption does not exceed the predicted minimum value is not satisfied afterwards, it is not possible to consume all of the surplus power with all the power loads of the dwelling units receiving surplus power interchange. Can be avoided.

According to the collective power receiving and transforming system according to the present invention, since the distributed power generation device (fuel cell power generation device) installed in a part of the plurality of dwelling units is always rated, the energy saving effect and CO ₂ saving effect of the power generation device. Further, the peak cut effect can be utilized to the maximum, and the social contribution per unit of the fuel cell power generator can be maximized. Furthermore, the economic merit of supplying power by the collective power receiving and transforming system is secured for the power management company that supplies the first low-voltage power to each dwelling unit. As a result, it is promoted that the same power management company applies the collective power receiving / transforming system according to the present invention to many apartment houses, etc., and the constant rated operation of the fuel cell power generation device has spread, and the above-mentioned energy saving effect saving CO ₂ effects, and expansion of social contributions by peak cut effect, etc. can be expected.

The block diagram which shows typically the example of 1 structure in 1st Embodiment of the package receiving / transforming system which concerns on this invention. The block diagram which shows typically the connection example of one structural example of a distributed generator, and the distributed generator in a specific dwelling unit, and its peripheral device. The graph which shows the average power consumption (unit: kWh) per one hour for every hour of the condominium for families. The block diagram which shows typically the example of 1 structure in 2nd Embodiment of the package receiving / transforming system which concerns on this invention. The block diagram which shows typically the example of 1 structure in 3rd Embodiment of the package receiving / transforming system which concerns on this invention. The block diagram which shows typically another structural example in 3rd Embodiment of the package receiving / transforming system which concerns on this invention.

  Embodiments of a collective power receiving and transforming system according to the present invention (hereinafter abbreviated as “the present system” where appropriate) will be described in detail with reference to the drawings.

[First Embodiment]
As shown in FIG. 1, the present system 1 according to the first embodiment includes a first power receiving / transforming facility 10 managed by a power management company (hereinafter referred to as “first company”), and a first company. The first distribution network 11 is laid in the area A to be managed.

  The first power receiving / transforming facility 10 is configured to include a transformer that receives high voltage power supplied from the commercial grid power source S and steps down the voltage to first low voltage power. The first power receiving / transforming equipment 10 is configured to include various instruments, switches, circuit breakers, current transformers, capacitors, relays, etc. in addition to the transformer, as in general power receiving / transforming equipment. Since the specific device configuration is not the gist of the present invention, the description is omitted. The first low-voltage power is applied to each power load ELi (i = 1 to n) of a plurality of dwelling units Hi (i = 1 to n, where n is the total number of dwelling units) existing in the area A managed by the first operator. And supplied separately via the first distribution network 11. The integrated electric energy for each predetermined unit integration period (for example, one month) of the high-voltage power supplied from the commercial power supply S to the first power receiving / transforming facility 10 is measured by the high-voltage first watt-hour meter M1. In the present embodiment, as the high-voltage power, AC power of more than 600 V and 7000 V or less is assumed, and as an example, AC power of 6600 V is assumed. As the first low-voltage power, an AC power of 600 V or less is assumed, and a single-phase three-wire 200 V AC power is assumed as an example. The first watt-hour meter M1 is a watt-hour meter managed and operated by the power company of the commercial power supply S, and is not included in the system 1.

  In each dwelling unit Hi, a predetermined unit integration of the total power of the distribution board 12 and the first low-voltage power supplied from the first distribution network 11 via the distribution board 12 to each power load ELi and surplus power described later. A low-voltage second watt-hour meter M <b> 2 that measures the integrated electric energy for each period (for example, one month) is installed. The second watt-hour meter M <b> 2 is interposed at a pull-in point between the first distribution network 11 and the distribution board 12. The first operator manages the meter reading of the second watt-hour meter M2. The meter reading is a smart meter configured such that the second watt-hour meter M2 transmits predetermined information including the meter reading value to a predetermined server or the like via a wired or wireless communication path, or a constant electric energy In the case of a watt-hour meter with a pulse transmission that transmits a pulse signal once every time (for example, 1 kWh) is integrated, automatic automatic meter reading is possible remotely. May be.

  Furthermore, in this system 1, one or more specific dwelling units HEj (j = 1 to m, m is the number of specific dwelling units, m <n), which are a part of the plurality of dwelling units Hi (i = 1 to n). Is a distributed generator that consumes fuel (city gas, LP gas, etc.) supplied from the outside and generates power of the same voltage, frequency, and electrical method (number of phases and lines) as the first low-voltage power The apparatus 20 is installed separately. In the present embodiment, the distributed power generator 20 is a fuel cell power generator, and as schematically shown in FIG. 2, a desulfurizer 21, a reformer 22, a fuel cell stack 23, an inverter device 24, A heat exchanger 25 and an operation control device 26 that controls these operations are provided. In addition, city gas (natural gas), which is a fuel, is a gas pipe (main branch pipe, supply pipe, etc.) laid outside the area from an external gas supply source G (outside area gas holder, etc.) and a gas laid inside the area A. It is supplied to the distributed power generator 20 of each specific dwelling unit HEj through the pipe 13. The city gas supplied to the distributed generator 20 is desulfurized by the desulfurizer 21 and then reformed by the reformer 22 to generate hydrogen. The hydrogen is supplied to the fuel electrode of the cell stack 23, and DC power is generated in the cell stack 23. The DC power generated by the cell stack 23 is converted by the inverter device 24 into single-phase three-wire 200V AC power that is the same as the first low-voltage power. The AC power output from the inverter device 24 is configured to be able to be supplied to the power load ELj of each dwelling unit HEj in the distribution board 12 in conjunction with the first low-voltage power supplied from the first distribution network 11. Has been. In the present embodiment, the distributed power generator 20 includes a case where the fuel cell is formed of a solid oxide fuel cell (SOFC) cell stack and the rated output Pf of AC power output from the inverter device 24 is 700 W. Suppose.

  A part of the heat energy of the waste heat recovered by the heat exchanger 25 is used as a heat source for the reformer 22, and the other part is used to heat water from the water supply. The high-temperature water heated by the heat exchanger 25 is stored in a hot water storage tank T provided in the distributed power generator 20 and supplied to a hot water supply load HLj such as a bathtub, a hot water shower, a hot water tap, and a hot water heater. With this configuration, the distributed power generation apparatus 20 of the present embodiment functions as a combined heat and power supply apparatus.

  In addition, in the dwelling units Hi other than the specific dwelling unit HEj, it is assumed that the hot water supply of the hot water supply load HLi is performed by the gas water heater 14 or the like installed in each dwelling unit Hi. It is not limited to the container 14.

  Further, in the present system 1, the distributed power generation apparatus 20 is not limited to a predetermined case such as an earthquake or a temporary stop of the city gas supply in a gas meter or the like for safety reasons such as confirmation of gas leakage. It is set to always operate at rated power. For this reason, in the present system 1, surplus power generated when the power consumption in the power load ELj of the specific dwelling unit HEj is lower than the rated output 700 W of the distributed power generation device 20 flows backward to the first distribution network 11 side, The electric power load ELi of another dwelling unit Hi can be accommodated. The other dwelling unit Hi includes a specific dwelling unit HEj that does not generate surplus power in the distributed power generation device 20. Accordingly, the third low-voltage watt-hour meter M3 that measures the integrated power amount for each predetermined unit integration period (for example, one month) of the surplus power that flows backward from each specific unit HEj to the first distribution network 11 side, Each specific dwelling unit HEj is interposed at a pull-in point between the first distribution network 11 and the distribution board 12 of each specific unit HEj.

  Therefore, in each specific dwelling unit HEj, two watt-hour meters, a second watt-hour meter M2 and a third watt-hour meter M3, are installed in series between the first distribution network 11 and the distribution board 12. . However, the second watt-hour meter M2 is configured to calculate the total power of the first low-voltage power supplied from the first distribution network 11 side to the distribution board 12 and surplus power (when it is interchanged from other specific dwelling units HEj). Only the amount of electric power is integrated, and the surplus electric power flowing from the distribution board 12 toward the first distribution network 11 is not measured, that is, is not integrated as a negative electric energy. Conversely, the third watt-hour meter M3 integrates only the amount of surplus power flowing from the distribution board 12 toward the first distribution network 11 side, toward the distribution board 12 from the first distribution network 11 side. The total power of the supplied first low-voltage power and surplus power is not measured. The first business operator may manage the meter reading of the third watt-hour meter M3, but a power management business operator (hereinafter referred to as "second business operator") different from the first business operator. Assume the case to do. The power management business that manages meter reading of the third watt-hour meter M3 is a power management business that purchases or manages surplus power from each specific dwelling unit HEj based on the meter-reading value of the third watt-hour meter M3. The meter reading is a smart meter configured such that the third watt-hour meter M3 transmits predetermined information including the meter reading value to a predetermined server or the like via a wired or wireless communication path, or a constant electric energy In the case of a watt-hour meter with a pulse transmission that transmits a pulse signal once every time (for example, 1 kWh) is integrated, automatic automatic meter reading is possible remotely. May be.

  Further, in the present system 1, the total Pft of the generated power (rated output Pf) at the rated operation of the distributed generator 20 is the total power consumption of the plurality of dwelling units Hi (i = 1 to n) existing in the area A. The number m and the rated output Pf of the specific dwelling unit HEj are set so as not to exceed the predicted minimum value Dmin. In this embodiment, since the rated output Pf is fixed at 700 W, the total Pft of the rated outputs Pf is m times the number of houses of 700 W, and therefore the relationship between the predicted minimum value Dmin (unit: W) and the number of houses m is It is represented by the inequality shown in Equation 1 below.

[Equation 1]
700 × m <Dmin

Here, as a plurality of dwelling units Hi (i = 1 to n) existing in the area A, for example, a family apartment with about 3 to 4 family members is assumed. FIG. 3 is a family number three or four people about, the occupied area of the dwelling unit is 80m ² about Kansai 19 properties in the region of family-friendly condominium, the average power load of 1 units per every hour of the month in 7133 units (1 It is a graph which shows the average power consumption per unit / unit: kW). From FIG. 3, it can be seen that the minimum value of the average power load of a general household of 3 to 4 family members is about 200 W. Thus, in the above assumption, the predicted minimum value Dmin is given by (200W × n) obtained by multiplying 200W by the total number n of the plurality of dwelling units Hi. And the said number 1 is deform | transformed as shown in the following number 2, and the number m of the specific dwelling units HEj needs to be limited to less than 1 / 3.5 of the total number n of the plurality of dwelling units Hi. Here, some of the plurality of dwelling units Hi (i = 1 to n) become vacant houses, power consumption decreases due to a decrease in the number of families, or distributed power generation in the specific dwelling units HEj in dwelling units other than the specific dwelling units HEj Assuming the possibility that the device is introduced and used in power load following operation, etc., the error of the predicted minimum value Dmin, etc. The number m of houses may be set to be less than less than one-third of the total number n of the plurality of dwelling units Hi, and may be set to one quarter or less of the total number n of the plurality of dwelling units Hi.

[Equation 2]
m <n / 3.5

  In addition, when the rated output Pfj of the distributed generator 20 of each specific unit HEj is different depending on the specific unit HEj, the total Pft of the rated output Pf is the sum of the rated output Pfj individually for j = 1 to m. The above formula 1 is expressed by the following formula 3.

[Equation 3]
Σ _{j = 1 to m} (Pfj) <Dmin

  In the present system 1, as described above, since the distributed power generator 20 of each specific dwelling unit HEj is set to always perform rated operation, the operation state of the distributed power generator 20 is constantly monitored, and a plurality of There is no need to constantly control the dwelling unit Hi (i = 1 to n) according to the total power demand of the power load ELi. Furthermore, since the number of houses m and the rated output Pf of the specific dwelling unit HEj are set so that the total Pft of the rated output Pf of the distributed power generator 20 does not exceed the predicted minimum value Dmin, the dwelling unit receiving the surplus power accommodation It is possible to avoid the situation where all the surplus power cannot be consumed by all the power loads ELi of Hi, and it is possible to effectively use all the surplus power without waste in each power load ELi of the plurality of dwelling units Hi in the area A.

  In the present system 1, surplus power is supplied together with the first low-voltage power from the first distribution network 11 to the power load ELi of the dwelling unit Hi via the second wattmeter M2 and the distribution board 12. In the total value of the integrated electric energy of all the dwelling units Hi measured by the second watt-hour meter M2 during the unit integration period, the integrated electric energy of surplus power measured by the third watt-hour meter M3 during the unit integration period The total value of is included. That is, the amount of received high-voltage power received by the first power receiving / transformation facility 10 to supply the first low-voltage power is reduced by a considerable amount to the total value of the accumulated amount of surplus power. Therefore, surplus power is exchanged between the first operator and each specific dwelling unit HEj (j = 1 to m), and surplus power measured by the third watt-hour meter M3 in the same unit integration period. It is necessary to pay directly or indirectly between the first business operator and each specific dwelling unit HEj for the settlement of the power charge related to the accumulated power amount. In the present embodiment, it is assumed that the management of the meter reading of the third watt-hour meter M3 and the like is performed by the second operator, and therefore the second operator has the third electric energy for each specific dwelling unit HEj. The surplus power calculated based on the total value of the meter reading value of the third electricity meter M3 is paid to the first operator by paying a purchase fee of the accumulated amount of surplus power calculated based on the meter reading value of the meter M3. You will be billed for the amount of power you use. In addition, when the 1st provider manages the meter reading of the 3rd electricity meter M3, etc., the 1st operator is based on the meter reading value of the 3rd electricity meter M3 with respect to each specific dwelling unit HEj. The purchase fee of the calculated cumulative amount of surplus power is paid directly.

[Second Embodiment]
As shown in FIG. 4, the system 2 according to the second embodiment includes a second power receiving / transformation facility 30 managed by a second operator and a second power distribution with respect to the system 1 of the first embodiment. It further comprises nets 31 and 32.

  The second power receiving / transforming facility 30 includes a transformer that receives high voltage power supplied from the commercial power supply S and steps down the voltage to second low voltage power. The second power receiving / transforming equipment 30 is configured to include various instruments, switches, circuit breakers, current transformers, capacitors, relays, etc. in addition to the transformer, as in general power receiving / transforming equipment. Since the specific device configuration is not the gist of the present invention, the description is omitted. The second low-voltage power is supplied to the power loads CEL1, CEL2 of the shared facilities 33, 34 shared by the residents of the plurality of dwelling units Hi (i = 1 to n) existing in the area A via the second distribution networks 31, 32. Supplied separately. As the shared equipment 33, lighting and outlets of the shared facility are assumed, and as the shared equipment 34, power equipment such as an elevator or an escalator is assumed.

  In the present embodiment, as in the first embodiment, the high voltage power is assumed to be 600V to 7000V AC power, and as an example, 6600V AC power is assumed. As the second low-voltage power, an AC power of 600 V or less is assumed. As an example, a single-phase three-wire 200 V AC power for the common facility 33 and a three-phase three-wire power source for the common facility 34 are used. Assume 200V AC power. Therefore, in the present embodiment, the second power receiving / transforming equipment 30 is configured to output two types of second low-voltage power, a single-phase three-wire system 200V and a three-phase three-wire system 200V.

  A high-voltage fourth watt-hour meter M4 is interposed between the secondary side of the first watt-hour meter M1 and the primary side of the second power receiving / transforming facility 30. Further, a fifth watt-hour meter M5 for low voltage (single-phase three-wire system 200V) is interposed between the output terminal of the single-phase three-wire system 200V of the second power receiving / transforming equipment 30 and the second distribution network 31, A sixth watt-hour meter M6 for low voltage (three-phase three-wire system 200V) is interposed between the output terminal of the single-phase three-wire system 200V of the second power receiving / transforming facility 30 and the second distribution network 31.

  The integrated electric energy for each predetermined unit integration period (for example, one month) of the high-voltage power supplied from the commercial power supply S to the second power receiving / transforming facility 30 is measured by the fourth watt-hour meter M4. Further, the integrated power amount of the second low-voltage power (single-phase three-wire system 200V) supplied from the second power receiving / transforming facility 30 to the shared facility 33 every predetermined unit integration period (for example, one month) is the fifth power. The integrated electric energy of the second low-voltage power (three-phase three-wire system 200V) measured by the meter M5 and supplied from the second power receiving / transforming facility 30 to the shared facility 34 is measured by the sixth watt-hour meter M6.

  In the present system 2, the high-voltage power supplied from the commercial power supply S branches off on the secondary side of the first watt-hour meter M <b> 1 and is supplied to the first power receiving / transforming equipment 10 and the second power receiving / transforming equipment 30. Therefore, the integrated electric energy of the high-voltage power measured by the first watt-hour meter M1 during a certain unit integration period includes the high-voltage power supplied to the second power receiving / transforming facility 30 and measured by the fourth watt-hour meter M4. The accumulated power is included. Therefore, it is necessary for the second business operator to pay the power fee for the integrated power amount of the high-voltage power measured by the fourth power meter M4 to the first business operator.

  Moreover, in this embodiment, the electric power charge with respect to each integrated electric energy of 2 types of 2nd low voltage electric power measured by the 5th watt-hour meter M5 and the 6th watt-hour meter M6 in a certain unit integration period is 2nd business. The operator makes a charge to a business operator that manages the shared facilities 33 and 34 (for example, an apartment management association).

[Third Embodiment]
As shown in FIGS. 5 and 6, the systems 3 and 4 according to the third embodiment are different from the system 1 according to the first embodiment and the system 2 according to the second embodiment, respectively. An ammeter M7 interposed at the end of the distribution network 11 on the first power receiving / transforming facility 10 side, and a signal line 35 connecting the ammeter M7 and each distributed power generator 20 are further provided. .

  In the present embodiment, the distributed power generation device 20 includes a control function for adjusting the power generation output in accordance with a signal value such as a control signal input from the outside in the operation control device 26 provided in the distributed power generation device 20. Assuming that The ammeter M7 is configured to include a current transformer (current transformer), and measures the current value of the first low-voltage power flowing through the end of the first distribution network 11 on the first power receiving / transforming equipment 10 side. An output signal (current signal) indicating a secondary current value reduced at a constant current ratio with respect to the current value is generated for the number m of the distributed power generators 20 and output.

  Each of the distributed power generation devices 20 receives an output signal indicating the secondary current value from a signal input terminal provided in the operation control device 26. The operation control device 26 reads the secondary current value of the received output signal in real time or at a constant sampling period, and is operating when the read secondary current value is equal to or less than a predetermined reference value I2r. The operation shifts from the rated operation to the operation at a constant intermediate output that is decreased in accordance with the secondary current value from the rated output.

  Since the current value of the first low-voltage power output from the secondary side of the first power receiving / transforming facility 10 decreases as the total amount of surplus power flowing backward from each distributed power generator 20 to the first distribution network 11 increases. When the current value of the first low-voltage power (primary current value of the ammeter M7) decreases to the reference lower limit value I1r before it decreases to zero, the ammeter M7 reduces the primary current value. By detecting as the secondary current value of the reference value I2r, when the surplus power further increases and the primary current value decreases, the distributed power generator 20 shifts from the rated operation to the intermediate output operation. The increased surplus current decreases. The current value of the first low-voltage power increases due to a decrease in surplus current due to the shift to the intermediate output operation or a decrease in surplus current due to an increase in the total power (total power consumption) of the power load ELi, and the ammeter M7 When the secondary side current value exceeds the reference value I2r, the operation control device 26 returns to the rated operation from the intermediate output operation in operation. When the secondary current value of the ammeter M7 is equal to or less than the reference value I2r, the intermediate output operation is maintained with an intermediate output corresponding to the secondary current value at that time. If the surplus power increases due to the return to the rated operation and the secondary current value of the ammeter M7 becomes the reference value I2r or less, the surplus power is transferred again from the rated operation during operation to the intermediate output operation. Decrease. When the period during which the total power (total power consumption) of the power load ELi is at the lowest level has elapsed during the transition between the rated operation and the intermediate output operation, the distributed power generator 20 is stable. Return to rated operation.

  In the present systems 1 to 4, basically, each of the distributed power generation devices 20 is capable of reducing the total power (total power consumption) of the power loads ELi of the plurality of dwelling units Hi (i = 1 to n) to the lowest level. Since the number m of the specific dwelling units HEj is limited in advance so that rated operation is possible, the transition to the intermediate output operation does not normally occur. However, some of the multiple units Hi become vacant houses or long-term absences, power consumption decreases due to a decrease in the number of families, and distributed power generators are introduced in the specific units HEj in units other than the specific units HEj Then, there is a possibility that a situation such as a case where it is used in the power load following operation will occur after the fact. If the number m of the specific dwelling units HEj is set near the upper limit indicated by the above formula 1 or the formula 2 with respect to the initial total number n of the plurality of dwelling units Hi, when such a situation occurs, At a certain time when the total power (total power consumption) of the power load ELi is at the lowest level, by performing control to shift to the above-mentioned intermediate output operation, the surplus power at all power loads of the dwelling unit receiving surplus power accommodation It is possible to avoid a situation where all of the power is not consumed, that is, a situation where the total generated power during the rated operation of the distributed generator 20 exceeds the total power (total power consumption) of the power load ELi.

  In the above description, when the read secondary current value is equal to or less than the predetermined reference value I2r, the operation control device 26 is a constant value that is decreased from the rated output during operation according to the secondary current value. However, as another mode of the transition to the intermediate output operation, the operation may be shifted from the rated operation to the power load following operation.

  Furthermore, although the reference value I2r is set to the same value in each distributed power generation device 20, a different reference value may be used between the distributed power generation devices 20. In this case, each distributed power generator 20 does not shift from the rated operation to the intermediate output operation or the like at the same time, but shifts in stages. Thereby, the rapid fluctuation | variation of surplus electric power can be suppressed.

  The configuration in which the ammeter M7 outputs an output signal (current signal) indicating the secondary current value via the signal line 35 has been described. However, the ammeter M7 converts the secondary current value into a voltage amplitude. A configuration may be adopted in which an analog signal or a digital signal converted into a digital value is output as an output signal. Furthermore, when the operation control device 26 has a control input terminal for receiving a control signal from the outside and has a function of switching operation modes such as rated operation and intermediate output operation in accordance with the input of the control signal, It is good also as a structure which converts the output signal which shows the said secondary current value into the said control signal, and outputs it toward each distributed power generator 20. FIG. In these configurations, a conversion device that converts the output signal indicating the secondary current value into the analog signal, the digital signal, or the control signal is provided inside or outside the ammeter M7. In these configurations, each signal does not necessarily generate the number m of distributed generators 20, but when different reference values are used among the distributed generators 20, depending on how they differ. It suffices to generate the same number. When outputting the digital signal or the control signal, the signal line 35 may be configured using a wireless communication path as a transmission medium for the output signal. For example, when the specific dwelling units HEj are dispersed in a wide area A, it is preferable to use a wireless communication path.

  In the above description, the case where the operation control device 26 shifts from the rated operation to the intermediate output operation in accordance with the output signal or control signal output from the ammeter M7 or the conversion device has been described. Instead of, or in addition to, shifting to the output operation, the switch provided at the output end of the inverter device 24 is opened and connected to the distribution board 12 (that is, connected to the first low-voltage power). The reverse flow of surplus power from the distributed generator 20 to the first distribution network 11 may be stopped by shutting off the system.

  In the distributed generator 20, the distribution board 12 is provided with a current transformer (current transformer), and the operation control device 26 monitors the secondary current of the current transformer to identify the current from the first distribution network 11. There is a case where the current of the power supplied to the power load LEj side of the dwelling unit HEj (in this embodiment, the total power of the first low-voltage power and the surplus power) can be monitored. Furthermore, in such a configuration, as described above, when the control is performed to open the switch and stop the reverse power flow of the surplus power from the distributed power generator 20 to the first distribution network 11, the distributed power generator 20 Since the monitored current is flowing even though the output of the power is stopped, the operation control device 26 determines that it is in an error state and performs a predetermined emergency treatment (such as operation stop of the distributed generator 20). May be set to do. Therefore, in such a case, in order to avoid that the operation control device 26 performs the emergency treatment, at the same time when the switch is opened, the secondary side terminals of the current transformer are short-circuited to virtually monitor. It is preferable that no current is flowing. Here, if the switch provided on the signal line connecting the current transformer and the operation control device 26 is opened, the secondary terminal of the current transformer is opened and a high voltage is generated. Since there is a risk of breakdown such as insulation breakdown, it is necessary to short-circuit between the terminals on the secondary side of the current transformer. Furthermore, it is also preferable to perform a control for shifting the operation of the distributed generator 20 from the rated operation to the idling operation simultaneously with opening the switch.

  Furthermore, instead of the ammeter M7, a wattmeter or a watthour meter that measures the amount of power every predetermined relatively short unit period (for example, 1 to 10 minutes) may be used.

[Another embodiment]
Next, modified examples of the above embodiments will be described.

  <1> In each of the above embodiments, each of the distributed power generation devices 20 is assumed to be a fuel cell power generation device including a cell stack of a solid oxide fuel cell (SOFC). The power generation device is not limited to the SOFC, and may be, for example, a polymer electrolyte fuel cell (PEFC). Further, when the number m of the distributed power generators 20 is plural, the distributed power generators 20 of different types of fuel cells, for example, the SOFC distributed power generator 20 and the PEFC distributed power generator 20 are mixed. Also good.

  Furthermore, although the case where the rated output Pf of the distributed generator 20 is 700 W is assumed, the rated output Pf is not limited to 700 W, and the rated output Pf is distributed among the plurality of distributed generators 20. Need not be common.

  <2> In each of the above-described embodiments, one smart meter, for example, the integrated power amount every 30 minutes of the first low-voltage power supplied from the first distribution network 11 toward the distribution board 12, and the distribution board For example, the accumulated power amount of every 30 minutes of surplus power that flows backward from 12 to the first distribution network 11 is individually measured and stored for a predetermined storage period of one month or longer, for example, at regular intervals (for example, 2), the second watt-hour meter M2 and the third watt-hour meter M3 may be configured by the one smart meter.

  Furthermore, in each said embodiment, the 3rd electricity meter M3 accumulate | stores only the electric energy of the surplus electric power which flows toward the 1st distribution network 11 side from the distribution board 12, and distributes electricity from the 1st distribution network 11 side. Although the case where it was comprised so that the total electric power of the 1st low voltage electric power and surplus electric power supplied toward the board | substrate 12 might not be measured, the provider who manages meter-reading etc. of the 3rd electricity meter M3, When the second operator is different from the first operator who manages the second electricity meter M2, the third electricity meter M3 is supplied from the first distribution network 11 side to the distribution board 12. It is also preferable that the total power amount of the first low-voltage power and surplus power can be separately measured separately from the surplus power amount that flows backward. Thereby, the measurement function similar to the 2nd watt-hour meter M2 can be added to the 3rd watt-hour meter M3, and the 2nd provider also has the electric power supplied to each specific dwelling unit HEj from the 1st power distribution network 11. The amount can be monitored.

  <3> In the collective power receiving dwelling system 4 of the second embodiment, the shared facility 43 is assumed to be lighting and outlets of the shared facility, and the shared facility 44 is assumed to be a power facility such as an elevator or an escalator. Even if both of the shared facilities 43 and 44 are not provided, only one of the shared facilities may be provided.

  In addition, the collective power receiving dwelling system 2 of the first embodiment corresponds to a case where both the shared facilities 43 and 44 are not provided. For example, the case where each of the plurality of dwelling units Hi (i = 1 to n) is a detached house is assumed.

  <4> In each of the above embodiments, in at least a part of the specific dwelling unit HEj, a storage battery is installed, and when the storage battery is not fully charged, a part of the generated surplus power is charged to the storage battery, and the power load When ELj exceeds the rated output (700 W) of the distributed power generator 20, the excess power may be covered by the discharge of the storage battery. As a result, the total amount of surplus power flowing backward to the first distribution network 11 is reduced, but the cumulative amount of first low-voltage power supplied to the specific dwelling unit HEj is also reduced, so the first distribution network There is no change in the total integrated electric energy of the first low-voltage power supplied from 11 to each dwelling unit Hi.

  <5> In each of the above embodiments, a storage battery may be installed by connecting to the first distribution network 11. Here, the storage battery is completely discharged by the first period of 3 to 5 o'clock when the average power consumption shown in Fig. 3 is minimized, and the second period of 20 to 22:00 when the average power consumption is maximized. Charge / discharge control is performed so that the battery is fully charged by the time. According to the charge / discharge control, the total consumption of the plurality of dwelling units Hi (i = 1 to n) is assumed if some of the plurality of dwelling units Hi are vacant or absent, or the number of families is reduced. Even in the case where the predicted minimum electric power value Dmin is lower than the initial prediction, in the first period in which the total value of surplus power is maximum, the total value of the generated power during rated operation is temporarily Even if it exceeds the minimum value of the total power consumption that has fallen below the value Dmin, the excess can be charged into a fully discharged storage battery. In addition, during the second period when the total power consumption of a plurality of dwelling units Hi (i = 1 to n) is likely to be maximized, a part of the peak power demand is covered by the discharge of the fully charged storage battery. Thus, the peak output of the first low-voltage power can be suppressed.

  Furthermore, it becomes possible to reduce the capacity | capacitance of the transformer of the 1st receiving / transforming equipment 10 only 700Wxm by carrying out rated operation of the distributed generator 20 of the specific residence HEj. If the capacity of the transformer of the first power receiving / transforming facility 10 is reduced by 700 W × m, one of the m distributed generators 20 has stopped operation for 24 hours due to maintenance or the like. Then, the supply amount of the first low-voltage power is insufficient for 700 × 24 (Wh) during the 24 hours. Therefore, when the capacity of the storage battery is set to 16.8 kWh or more, the shortage can be covered.

  <6> In each of the above embodiments, it is assumed that the distributed power generator 20 is installed only in the specific dwelling unit HEj, but even if the distributed power generation device is installed in a dwelling unit Hi other than the specific dwelling unit HEj. Good. However, the distributed power generators of the dwelling units Hi other than the specific dwelling unit HEj perform load following operation and do not generate surplus power, or even if generated, charge the storage battery or the like and do not reversely flow to the first distribution network 11 side. It is a condition. In this case, the predicted minimum value Dmin (= 200 W × n) of the total power consumption of the plurality of dwelling units Hi (i = 1 to n) is excluded from the total number n of dwelling units Hi, including the distributed power generators. Need to predict.

  <7> In each of the above embodiments, when the plurality of dwelling units Hi are detached houses, a solar power generation device is installed in a part of the plurality of dwelling units Hi (including the specific dwelling unit HEj), and output from the solar power generation device The AC power thus generated may be configured to be able to be supplied to the power load ELi of the dwelling unit Hi in connection with the first low-voltage power supplied from the first distribution network 11 inside the distribution board 12. Furthermore, the surplus power generated by the solar power generation device may be reversely flowed to the first distribution network 11 side to be accommodated in the power load ELi of another dwelling unit Hi. In this case, the surplus power generated by the solar power generation device is similar to the surplus power of the distributed power generation device 20, at the pull-in point between the first distribution network 11 and the distribution board 12 of the dwelling unit Hi. When the dwelling unit Hi is not the specific dwelling unit HEj through the electricity meter M3, the accumulated power amount of the surplus power of the solar power generation device is measured, and the dwelling unit Hi is the specific dwelling unit HEj. The total integrated power amount of the surplus power of the distributed power generation apparatus 20 and the surplus power of the solar power generation apparatus may be measured. Note that the solar power generation apparatus does not generate power because there is no solar radiation in the time zone in which the total power consumption of the plurality of dwelling units Hi (i = 1 to n) is the lowest, and thus does not affect the prediction of the predicted minimum value Dmin.

  This system can be used for a plurality of dwelling units that receive power supply by the collective high-voltage power receiving method.

1-4: Collective power receiving / transforming system 10: 1st power receiving / transforming equipment 11: 1st power distribution network 12: Distribution board 13: Gas piping 14: Gas water heater 20: Distributed generator 21: Desulfurizer 22: Reformer 23: Cell stack of fuel cell 24: Inverter device 25: Heat exchanger 26: Operation control device 30: Second substation equipment 31, 32: Second distribution network 33, 34: Shared equipment 35: Signal line A: In-area CEL1 , CEL2: Power load of shared equipment EL: Power load G: Gas supply source H: Dwelling unit HE: Specific dwelling unit HL: Hot water supply load M1: First electricity meter M2: Second electricity meter M3: Third electricity meter M4 : 4th electricity meter M5: 5th electricity meter M6: 6th electricity meter M7: Ammeter S: Commercial system power supply T: Hot water storage tank

Claims (5)

The first power receiving / transforming equipment is provided, and the power management company receives the high-voltage power supplied from the commercial power supply using the first power receiving / transforming equipment in a lump and steps down the voltage to the first low-voltage power. A collective power receiving and transforming system that supplies low-voltage power to each of the power loads of a plurality of dwelling units existing in the area to be managed by the power management company through a first distribution network laid in the area,
One or more specific dwelling units that are a part of the plurality of dwelling units in the area consume fuel supplied from the outside, and have the same voltage, frequency, and electric power as the first low-voltage power. Each has a distributed generator to generate electricity,
Each of the distributed power generators is configured to include a fuel cell, and is set to always operate at a rated value except for a predetermined case in which fuel supply from the outside stops, and the generated power of the distributed power generator Is configured to be able to supply power to the power load of the specific dwelling unit in conjunction with the first low-voltage power, and further, out of the generated power during rated operation of the distributed power generator, of the specific dwelling unit Each of the surplus power that was not consumed by the power load is configured to flow backward to the first distribution network and be accommodated in the power load of the other dwelling units in the area,
The number of units of the specific unit so that the total generated power at the rated operation of the distributed generator installed in the specific unit does not exceed the predicted minimum value of the total power consumption of a plurality of units existing in the area. And a power receiving / transforming system characterized in that the generated power during the rated operation is set.   The collective power receiving / transforming system according to claim 1, wherein the fuel cell included in the distributed power generation device is a solid oxide fuel cell.   The collective power receiving / transforming system according to claim 1 or 2, wherein the predicted minimum value is a value obtained by multiplying 200W by the total number of the plurality of dwelling units.   A second power receiving / transforming facility, the second power receiving / transforming facility is used to receive the high-voltage power supplied from the commercial power supply and step down to the second low-voltage power; The collective power receiving / transforming system according to any one of claims 1 to 3, wherein the collective power receiving system is supplied via a second distribution network to a power load of a common facility shared by residents of the dwelling unit. The current of the first low-voltage power supplied from the first power receiving / transforming facility toward the first power distribution network at the end of the first power distribution network on the first power receiving / transforming facility side, or a predetermined power It includes a measuring device that measures the amount of power per unit period, and outputs an output signal indicating the measured value, or a control signal that controls the operation of the distributed power generation device based on the measured value,
Between at least one of the measuring instrument and the distributed power generator is connected by a signal line capable of transmitting the output signal or the control signal,
In accordance with the output signal or the control signal, at least one of the distributed generators is configured to stop the rated operation and reduce the output power from the rated output, and to connect the first low-voltage power. The collective power receiving / transforming system according to any one of claims 1 to 4, wherein control for reducing the surplus power is performed by performing at least one of the processes to be cut off.

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