JP2015006044A - Power supply apparatus and power supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply apparatus and a power supply system, in which an autonomous operation switcher can be introduced to an existing dwelling easily and additionally.SOLUTION: A power supply apparatus supplies power to a load in a dwelling by using power supplied from a power system and power stored in a storage battery, while interconnecting the power system, and when the power system is interrupted, can continuously supply power to the load in the dwelling in use during the interconnection with the power system. The power supply apparatus includes, in one housing, a first terminal to which the power system is connected via a home distribution board, a second terminal to which the load in the dwelling is connected via the home distribution board, power system voltage monitoring means for monitoring a voltage of the power system, an electromagnetic contactor for separating between the first terminal and the second terminal during interruption of power supply, bidirectional power conversion means connected to the storage battery, for charging and discharging the storage battery, a current transformer for detecting an inverse load flow from a side of the bidirectional power conversion means to a side of the first terminal, and control means for controlling the electromagnetic contactor and the bidirectional power conversion means on the basis of the monitoring result by the power system voltage monitoring means and the detection result by the current transformer.

Description

  The present invention relates to a power supply device and a power supply system.

  In recent years, a system that uses natural energy such as solar power generation, and that charges low-cost electric power to the storage battery and discharges the electric energy charged in the storage battery to the load in the house during the day has become widespread. It's getting on. When a commercial power failure occurs, the power stored in these storage batteries can be supplied to a load in the house, and home appliances can be used even during a power failure. In case of independent operation when a commercial power failure occurs, two mechanical switching points or one switching point and one manual switching point are installed in accordance with the grid connection regulations (JEAC 9701-2012 NEC). There is a need to.

  In these systems, power is supplied only to a specific load during a self-sustaining operation during a power failure. On the other hand, a system that supplies power to the same load in a house that was used during grid connection during a power failure has been proposed.

  In Patent Document 1, when a commercial power supply source fails in a power supply system, the system interconnection relay is changed from “closed” to “open”, the commercial power supply source is disconnected, and the power storage unit is operated independently. In addition, it is described that the photovoltaic power generation unit and the fuel cell power generation unit are interconnected using the power source of the power storage unit as a reference power source. Thereby, according to patent document 1, it is supposed that a solar power generation part and a fuel cell power generation part can perform electric power generation similarly to the time of grid connection also in independent operation.

JP 2011-188607 A

  In the technique described in Patent Literature 1, it is considered that large-scale construction is required when an additional switch for independent operation is introduced into an existing house.

  For example, in the technology described in Patent Document 1, a storage battery is usually placed outdoors in a house, and a case of a power storage unit including a bidirectional converter that charges and discharges power to the storage battery and a control device is also installed outdoors. It is thought that it is almost done. At this time, in the technique described in Patent Document 1, a large number of wirings must be connected between the power storage unit and the distribution board, so that the wiring work is complicated and miswiring is likely to occur.

  For example, in the power supply system described in Patent Document 1, a voltage detection sensor for detecting whether the system is normal or a power failure in order to perform grid-connected operation when the system is normal and autonomous operation when the system is power failure. Is installed on the distribution board. The signal wiring for outputting the detection result of the voltage detection sensor needs to be routed to the system voltage monitoring unit of the power storage unit. In addition, in order to disconnect from the system during independent operation, the signal wiring for operating the switch (usually using an electromagnetic contactor) installed on the distribution board as well as the voltage detection sensor is connected to the power storage unit. It is also necessary to route to the column command section. Although not shown in Patent Document 1, since power from the power storage unit cannot flow backward to the grid side, a current transformer for detecting reverse power flow is installed on the distribution board, and the current The signal wiring for transmitting the output of the battery must be routed to the power storage unit control device of the power storage unit.

  These signal wirings become longer as the distance between the housing of the power storage unit installed outdoors and the distribution board of the power receiving unit becomes longer, which makes the signal wiring more susceptible to noise and power supply. The system may malfunction. Also, in order to reduce the influence of noise on the signal wiring, the main circuit wiring and the signal wiring are securely separated, and the use of shielded wires and other labor and costs for wiring work are large. It becomes. In addition, many signal wires, such as system voltage detection, disconnection switch operation, and reverse current detection, must be provided between the storage unit housing and the distribution board. There is a concern that the power supply system may not operate normally due to incorrect connection.

  For example, in the technique described in Patent Document 1, it is necessary to connect a self-sustained operation switching device mainly composed of a disconnection switch in a residential standard distribution board. For this reason, in the existing distribution board, it is necessary to incorporate a self-sustained operation switching device between the main earth leakage circuit breaker receiving power from the power company and the branch breaker that distributes power to the load in the house. Therefore, it is necessary to reconstruct the distribution board, and there is a possibility of spending a large amount of money and time for remodeling the existing distribution board.

  Further, in the technique described in Patent Document 1, a system voltage monitoring unit for detecting the occurrence of a power failure and a subsequent power recovery in the self-sustained operation switching device and an electromagnetic for disconnecting the commercial system during the self-sustaining operation. A disconnection command unit that opens and closes the contactor is provided, and although not shown, the wiring for monitoring the system voltage is a signal wiring that is different from the main circuit wiring. Therefore, a small-capacity breaker or fuse is required to protect the battery, and the size and mass of the self-sustained operation switching device tend to increase. Therefore, there is a possibility that a sufficient wall area for installing the self-sustaining operation switching device in the vicinity of the distribution board cannot be secured, and that the wall material cannot withstand the overload of the self-sustaining operation switching device. is there.

  This invention is made | formed in view of the above, Comprising: It aims at obtaining the electric power supply apparatus and electric power supply system which can introduce a self-sustained operation switching device easily into the existing house.

  In order to solve the above-described problems and achieve the object, an electric power supply device according to one aspect of the present invention uses electric power supplied from the system and electric power stored in a storage battery while connecting to the system. A power supply device capable of continuously supplying power to the in-house load being used during grid connection when the grid is interrupted and power is supplied to the in-house load. A first terminal to which the system is connected via an electrical panel; a second terminal to which the residential load is connected via the residential distribution panel; and a system voltage monitor for monitoring the voltage of the system. Means, an electromagnetic contactor separating between the first terminal and the second terminal at the time of a power failure, bidirectional power conversion means connected to the storage battery and charging / discharging the storage battery, Detecting reverse power flow from the bidirectional power conversion means side to the first terminal side A current transformer and a control means for controlling the electromagnetic contactor and the bidirectional power conversion means based on the monitoring result of the system voltage monitoring means and the detection result of the current transformer are housed in one housing. It is characterized by that.

  According to the present invention, it is possible to easily introduce a self-sustained operation switching device into a house.

FIG. 1 is a diagram illustrating a configuration of a power supply system according to an embodiment. FIG. 2 is a diagram showing internal wiring of the residential distribution board in the embodiment. FIG. 3 is a diagram illustrating a configuration of a power supply system according to a modification of the embodiment. FIG. 4 is a diagram illustrating a configuration of a power supply system according to a basic form.

  Hereinafter, embodiments of a power supply system according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment.
A power supply system 100 according to an embodiment will be described with reference to FIG. FIG. 1 is a diagram illustrating a configuration of the power supply system 100.

  The power supply system 100 is provided in a house, for example, and is connected to the commercial system 1 and uses the power supplied from the commercial system 1 and the power stored in the storage battery 11 to load in the house 19-1 to 19-. Supply power to k. For example, when solar power generation is performed during the daytime, the power supply system 100 stores excess power from the natural energy such as the solar power generation unit 6 to the residential loads 19-1 to 19-k. 11, the storage battery 11 is also charged from the commercial system 1, and power is supplied from the storage battery 11 to the in-house loads 19-1 to 19-k. For example, when solar power generation is not performed such as at night, the power supply system 100 charges the storage battery 11 from the commercial system 1 and supplies power from the storage battery 11 to the loads 19-1 to 19-k in the house.

  Further, in the power supply system 100, when the commercial system 1 fails, the electromagnetic contactors 5a and 5b, which are disconnecting switches in the power supply device 10, are disconnected from the commercial system 1 side, and the storage battery 11 and the like are connected. It uses and carries out the self-sustained operation which can supply electric power continuously to the load 19 in the house same as the time of grid connection among the loads 19-1 to 19-k in the house.

  In this way, the power supply system 100 is a system that uses natural energy and the storage battery 11, and continuously supplies power to the load in the same house that was used during grid connection during a self-sustaining operation in the event of a power failure. it can.

  Here, let us consider a power supply system 900 in which a part of a self-sustained operation switch 903 is incorporated in a residential distribution board 918 as shown in FIG. The power supply system 900 includes a commercial system 901, a solar power generation unit 906, a fuel cell power generation unit 908, a power storage unit 910, and a residential distribution board 918. In addition, the power supply system 900 includes a self-sustained operation switching device 903 that is partly incorporated in the residential distribution board 918 and the remaining part is incorporated in the power storage unit 910.

  The solar power generation unit 906 generates power using sunlight. The fuel cell power generation unit 908 generates power using the fuel cell. The power storage unit 910 includes a storage battery 911, a bidirectional converter 912, and a power storage unit control device 915. The bidirectional converter 912 has a function of charging the storage battery 911 with power supplied from the solar power generation unit 906 and the fuel cell power generation unit 908 and discharging the charged power. The power storage unit control device 915 controls the bidirectional converter 912 so that power is charged in the storage battery 911 or power is discharged from the storage battery 911.

  The electric power of the commercial system 901, the solar power generation unit 906, the fuel cell power generation unit 908, and the power storage unit 910 can be switched so as to flow electrically in the residential distribution board 918. To the in-house loads 19-1 to 19-k. Moreover, when the power consumption of the residential loads 19-1 to 19-k is small, the surplus power of the solar power generation unit 906 may flow backward to the commercial system 901 side.

  In order to supply power to the in-house loads 19-1 to 19-k as a self-sustained operation even when the commercial system 901 has a power failure, the presence or absence of the system voltage is detected by the sensor 927 in the residential distribution board 918 at the time of the power failure. . The system voltage monitoring unit 916 acquires the detection value of the sensor 927 and monitors the presence or absence of the system voltage according to the acquired detection value. When system voltage monitoring unit 916 recognizes that there is no system voltage, that is, that a power failure has occurred, it notifies power storage unit control device 915 of the occurrence of the power failure. In response to the notification of the occurrence of a power failure, the power storage unit control device 915 controls the disconnection command unit 917 so that the disconnection command unit 917 changes the electromagnetic contactors 905a and 905b from “closed” to “open”. As a result, the electromagnetic contactors 905a and 905b are the main circuit of the power storage unit 910 including the storage battery 911 and the bidirectional converter 912, the photovoltaic power generation unit, at two mechanical opening and closing points as defined by the grid connection regulations. 906, the electrical connection between the residential load 19 side including the fuel cell power generation unit 908 and the commercial system 901 side is cut off and disconnected. Therefore, even during a power failure, the power storage unit 910, the solar power generation unit 906, and the fuel cell power generation unit 908 can supply power to the same in-house load 19 that was used before the power failure.

  However, in the power supply system 900, since it is necessary to incorporate a part of the self-sustained operation switch 903 in the residential distribution board 918, when the self-sustained operation switch 903 is additionally introduced into an existing house, a large scale is required. Construction is considered necessary.

  For example, in the power supply system 900, the storage battery 911 is usually placed outdoors in a house, and a case of the power storage unit 910 including a bidirectional converter 912 that charges and discharges power to the storage battery 911, a power storage unit control device 915, and the like. It is considered that most of them are installed outdoors. At this time, in the power supply system 900, since a large number of signal lines L901 to L908 and the main circuit line L909 must be connected between the power storage unit 910 and the residential distribution board 918, wiring work is complicated. Yes, miswiring is likely to occur.

  For example, in the power supply system 900, for commercial grid connection operation when the commercial system 901 is normal, and for the commercial system 901 to perform independent operation during a power failure, voltage detection for detecting whether the commercial system 901 is normal or a power failure The sensor 927 is installed in the residential distribution board 918. The signal wiring L902 for outputting the detection result of the voltage detection sensor 927 needs to be routed to the system voltage monitoring unit 916 of the power storage unit 910 for wiring. Also, in order to disconnect from the commercial system 901 during the independent operation, switches 905a and 905b (usually electromagnetic contactors are used) installed in the residential distribution board 918 as well as the voltage detection sensor 927 are provided. It is also necessary to route the signal wirings L903 and L904 to be operated to the disconnection command unit 917 of the power storage unit 910. In addition, since the power from the power storage unit 910 cannot reversely flow to the grid side, a current transformer 914 for detecting the reverse power flow is installed in the residential distribution board 918 to detect the power of the power receiving unit. A current transformer 923, a current transformer 924 for detecting the power of the solar power generation unit 906, and signal wirings L 905 to L 908 for transmitting the output of the current transformer 925 for detecting the power of the fuel cell power generation unit 908, It is necessary to route and wire to the power storage unit control device 915 of 910.

  Since these signal wirings L901 to L908 become longer as the distance between the housing of the power storage unit 910 installed outdoors and the residential distribution board 918 of the power receiving unit becomes longer, the signal wirings L901 to L908 become longer. There is a possibility that the power supply system 900 may malfunction due to noise. Further, in order to reduce the influence of noise on the signal wirings L901 to L908, it is necessary to separate the main circuit wiring L909 and the signal wirings L901 to L908 from each other and to use a shielded wire. And the cost is large. Furthermore, it is necessary to provide a large number of signal wirings L901 to L908 between the housing of the power storage unit 910 and the residential distribution board 918, such as system voltage detection, disconnection switch operation, and reverse flow current detection. Therefore, there is a concern that the power supply system 900 may not operate normally due to incorrect connection during wiring work.

  In addition, for example, in an existing residential distribution board 18, a main circuit breaker (ELCB for power reception) 21 that receives power from an electric power company and a branch breaker 20 that distributes power to residential loads 19-1 to 19-k. It is necessary to incorporate a part (sensor 927 and electromagnetic contactors 905a and 905b) of the self-sustained operation switching unit 903 between −1 and 20-k.

  That is, as shown in FIG. 2, the standard residential distribution board 18 has a single-phase, three-wire electrical system drawn from the power company, and the main circuit breaker (power leakage circuit breaker) 21. The load side terminals 21a to 21c are connected to the power source side terminals 20a to 20c of the branch breakers 20-1 to 20-k, and are distributed to the outlets in each room. A single-phase three-wire neutral wire 32b and one of the remaining two lines 32a and 32c supply a voltage of 100V, and two lines 32a and 32c other than the neutral wire 32b supply 200V. The power supply side terminals 20a to 20c are connected to the branch breakers 20-1 to 20-k by BUS bars 31a to 31c made of copper.

  For example, the neutral wire 32b is connected to the N terminals of the branch breakers 20-1 to 20-k by a BUS bar (neutral phase copper bar) 31b via the power supply side terminal 20b. The line 32a is connected to the L terminals of the branch breakers 20-2, 20-4,..., 20-k by the BUS bar 31a through the power supply side terminal 20a. The line 32c is connected to the L terminals of the branch breakers 20-1, 20-3,..., 20- (k−1) by the BUS bar 31c via the power supply side terminal 20c.

  The load side terminals 21a to 21c shown in FIG. 2 correspond to the load side terminal 21d shown in FIG. 1, and the power supply side terminals 20a to 20c shown in FIG. 2 are connected to the power supply side terminal 20d shown in FIG. It corresponds.

  Since the load side terminals 21a to 21c of the main earth leakage circuit breaker 21 and the BUS bars 31a to 31c are connected by electric wires 33a to 33c, this wiring (electric wires 33a to 33c) is removed, and a part of the autonomous operation switching device 903 is removed. A mechanical remodeling work for enlarging the casing 18a is necessary so that the sensors 927 and the magnetic contactors 905a and 905b can be arranged.

  Further, in the power supply system 900 shown in FIG. 4, the respective power conversion devices of the solar power generation unit 906, the fuel cell power generation unit 908, and the power storage unit 910 are connected within the residential distribution board 918. In order to connect to these power generation units, it is necessary to install a breaker for protecting the wiring in the residential distribution board 918.

  Further, in the power supply system 900 shown in FIG. 4, it is not preferable that the power of the fuel cell power generation unit 908 and the power storage unit 910 flow backward to the commercial system 901 side, so a current transformer for detecting the reverse flow current It is necessary to install 914 in the residential distribution board 918.

  However, as shown in FIG. 2, in the existing residential distribution board 18, the casing 18a is sized according to the main earth leakage breaker 21 and the branch breakers 20-1 to 20-k. Since there is a high possibility that no extra space is provided, it is difficult to secure an empty space for installing a breaker or a current transformer. In other words, in order to secure a space for installing a breaker or a current transformer, it is necessary to remodel the existing residential distribution board 18, which requires a large amount of money for remodeling the existing residential distribution board 18. There is a possibility of spending time.

  Further, in the power supply system 900 shown in FIG. 4, a disconnection between the system voltage monitoring unit 916 for detecting the occurrence of a power failure and the subsequent power recovery and the commercial system 901 during the independent operation is performed in the autonomous operation switching unit 903. A disconnection command unit 917 for “opening” and “closing” the electromagnetic contactors 905a and 905b for performing the operation is provided, and the size of the self-sustained operation switching unit 903 is increased. Therefore, if a large installation area cannot be secured in the vicinity of the residential distribution board 918, it is difficult to install the self-sustained operation switching device 903. Moreover, since the mass of the self-sustaining operation switching device 903 is also heavy, there is a possibility that a problem such as that the wall surface material cannot withstand the excessive weight of the self-sustaining operation switching device 903 may occur.

  Therefore, in the embodiment, as shown in FIG. 1, the self-sustaining operation switching device 3 is incorporated in the housing 10 a of the power supply device 10, and the first terminal T <b> 1 of the power supply device 10 passes through the residential distribution board 18. Is connected to the commercial system 1, and the second terminal T <b> 2 of the power supply device 10 is connected to the residential loads 19-1 to 19-k via the residential distribution board 18, thereby routing the signal. The power supply system 100 can be easily constructed by greatly reducing the number of wiring lines.

  That is, in the power supply device 10, the system voltage monitoring unit 16, the magnetic contactors 5a and 5b, the disconnection command unit 17, the first breaker 7, the second breaker 9, the current transformers 14, 23, 24, 25, The bidirectional power conversion device 12 and the control device 15 are accommodated in one housing 10a. The system voltage monitoring unit 16 monitors the voltage of the commercial system 1. The magnetic contactors 5a and 5b are disconnected from the commercial system 1 during the self-sustaining operation. The disconnection command unit 17 “opens” and “closes” the magnetic contactors 5a and 5b. The breaker 7 protects an excessive current from flowing from the solar power generation unit 6. The breaker 9 protects an excessive current from flowing from the fuel cell power generation unit 8. The current transformer 14 detects a reverse power flow toward the commercial system 1 due to the electric power of the storage battery 11 and the fuel cell power generation unit 8. The bidirectional power converter 12 converts the power transmitted from the commercial grid 1 side to charge the storage battery 11 or converts the power discharged from the storage battery 11 to the residential loads 19-1 to 19-k side. Or bi-directional power conversion. The control device 15 controls each part of the power supply device 10 as a whole. For example, the electromagnetic contactors 5a and 5b and the bidirectional power converter 12 are controlled based on the monitoring result of the system voltage monitoring unit 16 and the detection results of the current transformers 14, 23, 24, and 25.

  Further, the housing 10a of the power supply apparatus 10 is provided with, for example, a first terminal T1 and a second terminal T2. The first terminal T1 is connected to the load side terminal 21d of the main circuit breaker 21 of the residential distribution board 18 via the main circuit wiring L1, and the second terminal T2 is connected to the main circuit wiring L2. The power supply side terminal 20d of the main circuit wiring of the branch breaker 20 is connected. Thereby, it is not necessary to connect the signal wiring between the power supply apparatus 10 and the residential distribution board 18, and it is only necessary to connect the two systems of the main circuit wirings L1 and L2.

  More specifically, the power supply apparatus 10 has a first terminal T1 and a second terminal T2 on the housing 10a. The first terminal T1 is a terminal to be connected to the load side terminal 21d of the main leakage breaker 21 in the residential distribution board 18 to which the commercial system 1 is supplied via the watt hour meter 2. It is arranged on the body 10a. The first terminal T1 is connected to the node N1 in the housing 10a. The second terminal T2 is a terminal for connecting the power supply side terminal 20d of the branch breaker 20 of the residential distribution board 18, and is arranged on the housing 10a. The second terminal T2 is connected to the node N3 in the housing 10a.

  The third terminal T3 is a terminal to which a power conversion device (not shown) of the solar power generation unit 6 is connected, and is arranged on the housing 10a. The third terminal T3 is connected to the node N2 via the first breaker 7 in the housing 10a. Moreover, it may be directly connected to the 1st breaker 7 in the housing | casing 10a from the power converter device (not shown) of the solar power generation part 6. FIG.

  The fourth terminal T4 is a terminal to which a power conversion device (not shown) of the fuel cell power generation unit 8 is connected, and is arranged on the housing 10a. The fourth terminal T4 is connected to the node N3 via the second breaker 9 in the housing 10a. Moreover, the power converter (not shown) of the fuel cell power generation unit 8 may be directly connected to the second breaker 9 in the housing 10a.

  The fifth terminal T5 is a terminal to which the storage battery 11 is connected, and is arranged on the housing 10a. The fifth terminal T5 is connected to the bidirectional power converter 12 in the housing 10a.

  The node N1 to which the first terminal T1 is connected is connected to the node N2 via two electromagnetic contactors 5a and 5b for disconnection installed in series. The node N1 is connected to the system voltage monitoring unit 16 through the signal line 16a, and the system voltage monitoring unit 16 is connected to the control device 15 through the signal line 16b. Thereby, in order to detect the voltage of the commercial system 1, the system voltage monitoring unit 16 detects the voltage of the node N1, and supplies a signal indicating the detection result (the voltage of the node N1) to the control device 15.

  The disconnection command unit 17 is connected to the control terminal of the electromagnetic contactor 5a via the signal line 17a, is connected to the control terminal of the electromagnetic contactor 5b via the signal line 17b, and is connected to the control device 15 via the signal line 17c. Is connected. Thereby, the disconnection command part 17 receives a control signal from the control apparatus 15, and opens and closes the electromagnetic contactors 5a and 5b according to the received control signal.

  The current transformer 14 is configured to detect the current when the power of the storage battery 11 and the power of the fuel cell power generation unit 8 cannot be consumed by the load 19 in the house and reversely flow to the commercial system 1 side. N3 is provided. The current transformer 14 is connected to the control device 15 through a signal line 14 a, and the detected value is supplied to the control device 15.

  The current transformer 23 is provided between the node N1 and the node N2 in order to detect the purchased power from the commercial system 1 or the sold power that is the surplus power of the solar power generation unit 6. The current transformer 23 is connected to the control device 15 through a signal line 23 a, and the detected value is supplied to the control device 15.

  The current transformer 24 detects the power generated by the solar power generation unit 6. For example, the current transformer 24 is provided on a branch line connecting the third terminal T3 and the node N2. The current transformer 24 is connected to the control device 15 through a signal line 24 a, and the detected value is supplied to the control device 15.

  The current transformer 25 detects the power generated by the fuel cell power generation unit 8. For example, the current transformer 25 is provided on the branch line connecting the fourth terminal T4 and the node N3. The current transformer 25 is connected to the control device 15 via a signal line 25 a, and the detected value is supplied to the control device 15.

  The magnetic contactors 5a and 5b for disconnection disconnect the first terminal T1 side that is the commercial system 1 side of the power supply apparatus 10 at the time of a power failure. The electromagnetic contactors 5a and 5b for disconnection receive a command from the disconnection command unit 17, for example, and open and close according to the command. The electromagnetic contactors 5a and 5b for disconnecting are accommodated in the housing 10a.

  The first breaker 7 is connected to the third terminal T3 of the power supply device 10 in order to connect the power conversion device (not shown) of the photovoltaic power generation unit 6 to the commercial system 1, and the housing 10a is used for wiring protection. Is housed inside. The first breaker 7 is normally in a closed state, but opens and closes a connection in accordance with a manual operation of a switch by a user, for example, in a maintenance check.

  The second breaker 9 is connected to the fourth terminal T4 of the power supply device 10 in order to connect the power conversion device (not shown) of the fuel cell power generation unit 8 to the commercial system 1, and the housing 10a is used for wiring protection. Is housed inside. The second breaker 9 is normally in a closed state, but opens and closes a connection in accordance with a manual operation of a switch by a user, for example, in maintenance and inspection.

  The third breaker 13 is housed in the housing 10 a in order to connect the bidirectional power conversion device 12 of the power supply device 10 to the commercial system 1. Although a detailed description is omitted, an earth leakage breaker is installed in the third breaker 13 in order to protect the earth leakage during the independent operation. The third breaker 13 is normally in a closed state, but opens and closes a connection in accordance with a manual operation of a switch by a user, for example, in maintenance and inspection.

  The main earth leakage circuit breaker 21 is housed in the residential distribution board 18 and is connected from the commercial system 1 via the watt-hour meter 2. The main earth leakage circuit breaker 21 is also called a service port device, and also serves as a main switch. Moreover, although not shown in figure, the main earth leakage circuit breaker 21 contains a contract breaker. For example, the main earth leakage breaker 21 is closed at a normal time when no electric leakage occurs, and is autonomously opened when the electric leakage occurs. Moreover, the main earth leakage circuit breaker 21 returns to a closed state, for example according to the manual operation of the switch by a user.

  Next, the operation of the power supply system 100 during normal times (when the commercial system 1 is not out of power) will be described.

  The main earth leakage breaker 21 and all branch breakers 20 (see FIG. 2) in the residential distribution board 18 are normally in the “closed” state. When the commercial system 1 is normal, the control device 15 of the power supply device 10 has the disconnection command unit 17 for the disconnection electromagnetic contactor 5a, The release command unit 17 is controlled so as to output a close command to 5b. The electric power generated by the solar power generator 6 is supplied to the residential load 19 via the residential distribution board 18 via the first breaker 7 in the power supply device 10.

  When the power generated by the solar power generation unit 6 exceeds the power consumed by the load 19 in the house, there is a possibility that surplus power flows backward to the commercial system 1. The electric power generated by the fuel cell power generation unit 8 is supplied to the residential load 19 via the residential distribution board 18 via the second breaker 9 in the power supply device 10. When the power consumption of the load 19 in the house is reduced and the surplus power generated by the fuel cell power generation unit 8 flows backward to the commercial grid 1, the current transformer 14 in the power supply device 10 detects the reverse power flow, The control device 15 that has received the detection result of the reverse power flow stops the power conversion device of the fuel cell power generation unit 8.

  The power supply device 10 charges the storage battery 11 with the electric power of the commercial system 1, the solar power generation unit 6, and the fuel cell power generation unit 8, and supplies electric power from the storage battery 11 to the residential load 19. The device 12 charges and discharges power. Similarly to the fuel cell power generation unit 8, the reverse power flow of the power of the storage battery 11 to the commercial system 1 is not preferable. Therefore, the reverse power flow is detected by the current transformer 14 in the power supply device 10, and the detection result of the reverse power flow is received. The control device 15 controls the discharge power of the bidirectional power converter 12 so as to suppress the reverse power flow (for example, the discharge power is reduced).

  Next, the operation of the power supply system 100 at the time of a power failure (when the commercial system 1 fails) will be described.

  When the commercial system 1 is blacked out, the power conversion device of the solar power generation unit 6, the power conversion device of the fuel cell power generation unit 8, and the bidirectional power conversion device 12 of the power supply device 10 each have no system voltage (power failure state). Usually, the operation is stopped when the grid connection protection function of undervoltage operates. When the system voltage monitoring unit 16 of the power supply device 10 detects that the system voltage has become 0 V due to a power failure, the control device 15 responds to the detection result (monitoring result) and manual operation, or the detection result ( Switch to self-sustaining operation by automatic operation according to the monitoring result. For example, the control device 15 instructs the disconnection command unit 17 to “open” the disconnecting electromagnetic contactors 5 a and 5 b in the power supply device 10 in order to cut off the electrical connection with the commercial system 1. The disconnection command unit 17 is controlled so as to be given. The control device 15 of the power supply device 10 confirms that the power supply device 10 is disconnected from the commercial system 1 by an auxiliary contact signal from the electromagnetic contactors 5a and 5b for disconnection, and then the power supply device 10 and solar power generation. Unit 6 and the fuel cell power generation unit 8 perform self-sustaining operation for supplying power to the load 19 in the house. In order to perform independent operation while a plurality of power generation facilities are operating simultaneously, special control such as phase synchronization is required, but details of the detailed control are omitted.

  By preparing the power supply apparatus 10 described above, it is possible to facilitate the construction when the power supply system 100 is constructed regardless of whether the house is an existing house or a new house.

  For example, in the case of an existing house, in order to construct the power supply system 900 shown in FIG. 4, the main earth leakage circuit breaker 21 also serving as the contract breaker in the residential distribution board 18 shown in FIG. And the wiring (electric wires 33a to 33c) connecting the branch breakers 20-1 to 20-k are removed, and a part of the self-sustaining operation switch 903 (the sensor 927 and the electromagnetic contactors 905a and 905b) is connected during this period. Electrical wiring work is required, and mechanical remodeling work is required to increase the size of the housing 18a so that a part of the self-sustained operation switching device 903 (sensor 927 and electromagnetic contactors 905a and 905b) can be arranged. Become. As described above, a large-scale construction for remodeling the existing residential distribution board 18 is required, and there is a possibility that a large amount of cost and time are spent on the modification work for the existing residential distribution board 18.

  On the other hand, in the embodiment, as shown in FIG. 1, between the load side terminal 21 d of the main earth leakage circuit breaker 21 of the residential distribution board 18 and the power source side terminal 20 d of the main circuit wiring of the branch breaker 20. The power supply system 100 can be easily constructed simply by connecting the casing 10a of the power supply apparatus 10 with the main circuit wires L1 and L2.

  As described above, in the embodiment, in the power supply device 10, the first terminal T1, the second terminal T2, the system voltage monitoring unit 16, the electromagnetic contactors 5a and 5b, the bidirectional power conversion device 12, the current transformation. The containers 14, 23, 24, 25 and the control device 15 are housed in one housing. The commercial system 1 is connected to the first terminal T1 via a residential distribution board 18. A residential load 19 is connected to the second terminal T2 via a residential distribution board 18. The system voltage monitoring unit 16 monitors the voltage of the commercial system 1. The magnetic contactors 5a and 5b disconnect between the first terminal T1 and the second terminal T2 during a power failure. The bidirectional power converter 12 is connected to the storage battery 11 and performs charging / discharging to the storage battery 11. The current transformer 14 detects a reverse power flow from the bidirectional power converter 12 side to the first terminal T1 side. The control device 15 controls the electromagnetic contactors 5a and 5b and the bidirectional power converter 12 based on the monitoring result of the system voltage monitoring unit 16 and the detection results of the current transformers 14, 23, 24, and 25. In the housing 10a of the power supply apparatus 10, the system voltage monitoring unit 16 and the magnetic contactors 5a and 5b are independent operation switching devices for switching the operation of the power supply system 100 to the independent operation when the commercial system 1 fails. 3 can function.

  That is, in the embodiment, the self-sustained operation switching device 3 is mounted in one housing 10a of the power supply device 10 so that the power supply device 10 and the residential use can be compared with the basic configuration (see FIG. 4). The number of wirings to and from the board 18 can be greatly reduced (for example, to two main circuit wirings L1 and L2). As a result, at the time of system construction, in the basic form (see Fig. 4), such as wiring for detecting system voltage, wiring for operating the disconnecting switch, and wiring for connecting the output of the current transformer Various necessary signal wiring work is no longer necessary, so that incorrect wiring can be prevented and the system can be operated reliably. That is, the self-sustained operation switching device 3 can be easily added to an existing house.

  Further, in the embodiment, since various signal lines can be aggregated in one casing 10a of the power supply apparatus 10, various signal lines can be shortened, and main circuit wiring and signal wiring are separated in the casing 10a. Therefore, it is possible to build a high-quality system that is less susceptible to noise due to inadequate wiring work during construction. That is, the reliability of the power supply system 100 including the power supply device 10 can be easily improved.

  Further, in the embodiment, a self-sustained operation switching device having a relatively large volume and mass is provided near the residential distribution board 18 in the power receiving section from the electric power company as compared with the basic mode (see FIG. 4). Since there is no need for installation, it is not necessary to secure installation space and reinforce the walls. Further, the wiring connecting the main earth leakage breaker and the branch breaker of the standard residential distribution board is removed, and only the main circuit wiring is connected to the power supply device 10 from the load side of the main earth leakage breaker and the power supply side of the branch breaker. A system can be constructed simply by connecting to the housing 10a, and the standard residential distribution board 18 can be used without having to be remodeled into a large one. That is, also from this point of view, the independent operation switching device 3 can be easily added to an existing house.

  Further, in the embodiment, since the self-sustained operation switching device 3 is mounted in one housing 10a of the power supply device 10 in the power supply device 10, the self-sustained operation required in the basic mode (see FIG. 4). Since the switch 903 is not required, it is not necessary to secure a wall to which the self-sustained operation switch 903 is attached or to reinforce the wall, and the installation work can be easily performed at a low cost.

  In the embodiment, in the power supply system 100, the load side of the main leakage breaker 21 of the distribution board 18 is connected to the first terminal T1 of the housing 10a, and the power supply of the branch breaker 20 of the distribution board 18 is established. Since the system can be constructed simply by connecting the side to the second terminal T2 of the housing 10a, it is possible to dispense with signal line wiring work during installation.

  In the embodiment, in the power supply device 10, the control device 15 controls the bidirectional power conversion device 12 based on the detection result of the current transformer 14. Thereby, when the reverse power flow from the bidirectional power converter 12 side to the first terminal T1 side (commercial system 1 side) occurs, the power conversion operation of the bidirectional power converter device 12 can be suppressed, and the reverse power flow can be reduced. Can be suppressed.

  In the embodiment, in the power supply device 10, the solar power generation unit 6 is connected to the third terminal T3, and the fuel cell power generation unit 8 is connected to the fourth terminal T4. The power supply device 10 supplies the power input via at least one of the third terminal T3 and the fourth terminal T4 to the load 19 in the house together with the power of the commercial system 1 and the power of the storage battery 11 at the time of grid connection. The power can be supplied, and power can be continuously supplied to the load 19 in the house at the time of a power failure. The current transformer 14 detects a reverse power flow from the bidirectional power converter 12 or the fourth terminal T4 side to the first terminal T1 side. The control device 15 controls the bidirectional power conversion device 12 based on the detection result of the current transformer 14. Thereby, even when a reverse power flow from the fuel cell power generation unit 8 side or the bidirectional power conversion device 12 side to the first terminal T1 side (commercial system 1 side) occurs, the power conversion of the bidirectional power conversion device 12 is performed. Operation can be suppressed and reverse power flow can be suppressed.

  In addition, in embodiment, although the electric power supply source of the electric power supply apparatus 10 is set as the storage battery 11, it is not limited to this. It goes without saying that the same effect can be obtained even if the power supply source is replaced with the storage battery 229 of the electric vehicle 230, which is expected to be spread in the future, as in the power supply system 200 shown in FIG. That is, the bidirectional power conversion device 212 of the power supply device 10 performs power charging / discharging on the storage battery 229 mounted on the electric vehicle 230. For example, when the capacity of the storage battery 229 is larger than that of the storage battery 11, the allowable power of the bidirectional power conversion device 212 may be larger than the allowable power of the bidirectional power conversion device 12. In this case, a large amount of electrical energy that can be stored can be secured.

  In addition, although the characteristic operation | movement was demonstrated separately in each embodiment, each embodiment can be combined freely and it can change and abbreviate | omit each embodiment suitably.

  As described above, the power supply system according to the present invention is a system that uses natural energy and a storage battery. During a self-sustained operation in the event of a power failure, the power supply system continues to power the same house used during grid connection. It is useful for the wiring work of the system that supplies power.

  1,901 Commercial system, 2 Electricity meter, 3,903 Self-sustained operation switcher, 21 Main earth leakage circuit breaker, 5a, 5b, 905a, 905b Magnetic contactor for disconnection, 6,906 Solar power generation unit, 7th 1 breaker, 8,908 fuel cell power generation unit, 9 second breaker, 10,910 power storage unit, 11,911 storage battery, 12,212 bidirectional power converter, 13 third breaker, 14, 23, 24, 25 Current transformer, 15 Control device, 16,916 System voltage monitoring unit, 17, 917 Disconnection command unit, 18,918 Residential distribution board, 19, 19-1 to 19-k Residential load, 20, 20 -1 to 20-k Branch breaker, 100,900 power supply system, 915 power storage unit control device, 912 bidirectional converter.

Claims (4)

While interconnecting with the grid, supplying power to the load in the house using the power supplied from the grid and the power stored in the storage battery, and when the grid fails, the power in use during grid interconnection A power supply device capable of continuously supplying power to a load in a house,
A first terminal to which the system is connected via a residential distribution board;
A second terminal to which the residential load is connected via the residential distribution board;
System voltage monitoring means for monitoring the voltage of the system;
An electromagnetic contactor that disconnects between the first terminal and the second terminal during a power failure;
Bidirectional power conversion means connected to the storage battery and charging / discharging the storage battery;
A current transformer for detecting a reverse power flow from the bidirectional power conversion means side to the first terminal side;
Control means for controlling the electromagnetic contactor and the bidirectional power conversion means based on the monitoring result of the system voltage monitoring means and the detection result of the current transformer;
An electric power supply device characterized in that it is housed in a single casing. A third terminal to which the solar power generation unit is connected;
A fourth terminal to which the fuel cell power generation unit is connected;
Further comprising
The power supply device supplies power input via at least one of the third terminal and the fourth terminal to the load in the house together with the power of the system and the power of the storage battery at the time of grid connection. Is possible, and can continuously supply power to the load in the house at the time of a power failure,
The power supply device according to claim 1, wherein the current transformer detects a reverse power flow from the bidirectional power conversion unit or the fourth terminal side to the first terminal side. A mains earth leakage circuit breaker and a branch breaker, wherein the grid is connected to the power source side of the main earth leakage circuit breaker, and the residential load panel is connected to the load side of the branch breaker;
The power supply device according to claim 1 or 2, wherein a load side of the main leakage breaker is connected to a first terminal, and a power source side of the branch breaker is connected to a second terminal;
A storage battery connected to the power supply device;
A solar power generation unit connected to the power supply device;
A power supply system comprising: The power storage system according to claim 3, wherein the storage battery is a storage battery mounted on an electric vehicle.

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