Power Distribution and Power Supply Systems

Abstract

To provide a power distribution system capable of controlling supply of power when a distributed power supply is connected to one outlet and power is supplied to other outlets from the distributed power supply.SOLUTION: A power distribution system 1 comprises an electromagnetic switch 24. The electromagnetic switch 24 is provided between a trunk breaker 132 and one outlet 3a in a cable way which connects a power system 2 with a plurality of outlets 3 and on which the trunk breaker 132 is provided between the power system 2 and the plurality of outlets 3. The electromagnetic switch 24 controls supply of power to another outlet 3b from a distributed power supply 4 in a closed state of the trunk breaker 132 and in a state in which power from the distributed power supply 4 connected to the one outlet 3a is supplied to the other outlet 3b of the plurality of outlets 3.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a power distribution system and a power supply system. More specifically, the present disclosure relates to a power distribution system capable of inputting power from a distributed power source to one outlet and supplying it to another outlet, and a power supply system including the power distribution system. [Background technology]

[0002] In the energy management system (distribution system) described in Patent Document 1, power from a main power source (a power grid, a storage battery, and a solar power generation device) is branched by a distribution board and supplied to a plurality of outlets. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-61418 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the energy management system described in Patent Document 1, for example, when the main breaker is tripped, the supply of power from the main power source to the multiple outlets is stopped, and the multiple outlets become unusable. In this case, there is a demand to connect a distributed power source to one outlet and supply power from the distributed power source to the other outlets, thereby making the other outlets usable.

[0005] However, in this usage method, the power supplied from the distributed power source to other outlets does not go through the main breaker, so the power supply from the distributed power source to other outlets cannot be controlled, and the system cannot be protected in the event of an abnormal current such as a ground leakage.

[0006] The present disclosure has been made in consideration of the above-mentioned reasons, and has an object to provide a power distribution system that is capable of controlling the supply of power when a distributed power source is connected to one outlet and power is supplied from the distributed power source to another outlet, and a power supply system that is equipped with the power distribution system. [Means for solving the problem]

[0007] A power distribution system according to one aspect of the present disclosure includes a second switch, the second switch being provided between a first switch and one of the outlets in an electric circuit that connects a power system and a plurality of outlets and in which a first switch is provided between the power system and the plurality of outlets. When the first switch is in an open state and power from a distributed power source connected to the one outlet is supplied to an outlet other than the one of the plurality of outlets, the second switch controls the supply of power from the distributed power source to the other outlet. When the first switch is in a closed state and the distributed power source is not connected to the one outlet, the second switch is controlled to a closed state. A power distribution system according to an embodiment of the present disclosure includes a second switch and a connection detection unit. The second switch is provided between a first switch and one of the multiple outlets in an electric circuit that connects a power system and multiple outlets and in which a first switch is provided between the power system and the multiple outlets. The connection detection unit detects whether or not the distributed power source is connected to the one outlet. When the first switch is in an open state and power from the distributed power source connected to the one outlet is supplied to another outlet other than the one outlet among the multiple outlets, the second switch controls the supply of power from the distributed power source to the other outlet. When the first switch is in a closed state and the distributed power source is not connected to the one outlet, the second switch switches from an open state to a closed state.

[0008] A power supply system according to one aspect of the present disclosure includes the power distribution system and the distributed power source. Effect of the Invention

[0009] The present disclosure provides an advantage in that when a distributed power source is connected to one outlet and power is supplied from the distributed power source to another outlet, the power supply can be controlled. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a block diagram including a power distribution system, a grid power distribution system, and a distributed power source according to an embodiment. [Diagram 2] FIG. 2 is a block diagram showing the above-mentioned power distribution system. [Diagram 3]FIG. 3 is an explanatory diagram illustrating an operation of the continuity detection unit of the power distribution system. [Figure 4] FIG. 4 is an explanatory diagram illustrating the operation of the pseudo earth leakage circuit of the power distribution system according to the embodiment of the present invention. [Diagram 5] FIG. 5 is a flowchart illustrating the operation of the above power distribution system. [Figure 6] FIG. 6 is a block diagram including a power distribution system and a grid power distribution system according to the fourth modification. [Figure 7] FIG. 7 is a block diagram of a power distribution system according to the fifth and sixth modifications. [Figure 8] FIG. 8 is a block diagram of a power distribution system according to the seventh modification. [Figure 9] FIG. 9 is a block diagram of a power distribution system according to the eighth modification. [Figure 10] FIG. 10 is a block diagram of a power distribution system according to the ninth modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] (Embodiment) A power distribution system 1 according to the present embodiment will be described with reference to FIGS. 1 to 5. FIG.

[0012] As shown in FIG. 1, the power distribution system 1 is provided in an electric circuit (main electric circuit 11 and branch electric circuit 12) that connects a power system 2 (also called system 2) and a plurality of outlets 3 and has a main breaker 132 (first switch) between the power system 2 and the plurality of outlets 3. More specifically, the power distribution system 1 is provided between the main breaker 132 and one of the plurality of outlets 3a in the above electric circuit. As a result, by connecting a distributed power source 4 to the one outlet 3a, it is possible to supply power from the distributed power source 4 to another outlet 3b other than the one outlet 3a among the plurality of outlets 3. At that time, the power supply can be controlled by the power distribution system 1. As a result, even if the supply of power from the power system 2 is stopped due to a disaster such as an earthquake or a typhoon, it is possible to supply power from the distributed power source 4 to an electric device 5 connected to the other outlet 3b while suppressing accidents due to abnormal current (e.g., leakage current).

[0013] In this embodiment, the electric device 5 can be directly connected to the one outlet 3a, but the distributed power source 4 can be connected via a relay cable 60. The power distribution system 1 will be described in detail below. In the following description, the one outlet 3a will also be referred to as a power receiving outlet 3a.

[0014] First, a description will be given of a grid power distribution system 10 installed in a building before a detailed description of the power distribution system 1. The grid power distribution system 10 is a system that distributes power from a power grid 2 to a plurality of outlets 3 installed in the building.

[0015] The grid power distribution system 10 receives power from the power system 2 via a pole transformer 6. More specifically, the power from the power system 2 is high-voltage (e.g., 6600V) single-phase two-wire AC power. The power system 2 and the pole transformer 6 are connected by two electric paths. The power from the power system 2 is transmitted from the power system 2 to the pole transformer 6 by the two electric paths. The pole transformer 6 steps down the power from the power system 2 to single-phase three-wire AC power of a predetermined voltage (e.g., 100V or 200V). The pole transformer 6 and the grid power distribution system 10 are connected by three electric paths. The power stepped down by the pole transformer 6 is transmitted from the pole transformer 6 to the grid power distribution system 10 by the three electric paths.

[0016] The pole transformer 6 includes a primary coil 61 and a secondary coil 62 wound around an iron core. Two electric circuits from the power grid 2 are connected to both ends of the primary coil 61. Three electric circuits from the power distribution system 10 are connected to both ends and the center of the secondary coil 62. The three electric circuits are an L1-phase electric circuit, an L2-phase electric circuit, and an N-phase electric circuit. The N-phase electric circuit is connected to the center of the secondary coil 62. The branch point B1 of the N-phase electric circuit is grounded at a ground point A1. The electrical resistance at the ground point A1 is, for example, 10Ω or less. The L1-phase electric circuit and the L2-phase electric circuit are each connected to both ends of the secondary coil 62. A voltage of 100V is applied to the L1-phase electric circuit and the L2-phase electric circuit, respectively, with respect to the N-phase electric circuit.

[0017] The grid power distribution system 10 includes a main electric line 11, a plurality of branch electric lines 12, a distribution board 13, a plurality of outlets 3, and a smart meter 14.

[0018] The main electric circuit 11 is an electric circuit that connects the pole transformer 6 and the power distribution system 10, and is drawn into the power distribution system 10. The main electric circuit 11 is made up of the above-mentioned three electric circuits (the L1-phase electric circuit, the L2-phase electric circuit, and the N-phase electric circuit).

[0019] The multiple branch electric circuits 12 are electric circuits branching out from multiple branch points on the main electric circuit 11, and are electric circuits connecting the main electric circuit 11 and the multiple outlets 3. Each of the multiple branch electric circuits 12 is composed of two electric circuits. The multiple outlets 3 include an L1 side outlet 3 and an L2 side outlet 3. The L1 side outlet 3 is connected to the L1 phase electric circuit and the N phase electric circuit of the main electric circuit 11 by the two electric circuits of the branch electric circuit 12. The L2 side outlet 3 is connected to the L2 phase electric circuit and the N phase electric circuit of the main electric circuit 11 by the two electric circuits of the branch electric circuit 12.

[0020] The distribution board 13 is a device that distributes power transmitted from the pole transformer 6 through the main circuit 11 to multiple outlets 3. The distribution board 13 includes a branch circuit 131, a main breaker 132, multiple branch breakers 133, and multiple ground terminals 134.

[0021] The branch circuit 131 is a circuit that distributes the power transmitted through the main electric circuit 11 to a plurality of outlets 3. The branch circuit 131 is composed of the main electric circuit 11 (more specifically, a portion of the main electric circuit 11 that is pulled into the inside of the distribution board 13) and a plurality of branch electric circuits 12.

[0022] The main breaker 132 (first switch) is provided upstream of a plurality of branch points in the main electric circuit 11. The main breaker 132 is provided downstream of the pole transformer 6 in the main electric circuit 11. In this embodiment, the main breaker 132 is provided in the main electric circuit 11, but may be provided at any position in the electric circuit between the power system 2 and the plurality of outlets 3. The main breaker 132 switches between an open state or a closed state depending on whether the amount of current flowing in the main electric circuit 11 exceeds a specified value (i.e., whether the current flowing in the main electric circuit 11 is an overcurrent). The main breaker 132 conducts and cuts off the main electric circuit 11 (the electric circuit between the power system 2 and the plurality of outlets 3) depending on the closed state or the open state. The main breaker 132 conducts and cuts off the power transmitted to the plurality of outlets 3 collectively.

[0023] In addition, when the main breaker 132 cuts off the main electric circuit 11, it means that all three electric circuits that make up the main electric circuit 11 are cut off, and when the main breaker 132 conducts the main electric circuit 11, it means that all three electric circuits that make up the main electric circuit 11 are conducted.

[0024] The main breaker 132 has a leakage current detection circuit 132a. That is, the main breaker 132 has a leakage current detection function. The leakage current detection circuit 132a detects whether or not there is a leakage current in the main circuit 11 via the main breaker 132 (i.e., the current supplied from the power system 2 to the multiple outlets 3). When the leakage current detection circuit 132a does not detect a leakage current, it maintains the main breaker 132 in a closed state to maintain the main circuit 11 in a conductive state. When the leakage current detection circuit 132a detects a leakage current, it switches the main breaker 132 from a closed state to an open state to cut off the main circuit 11. The main breaker 132 can be manually switched to an open state or a closed state. Therefore, when the main breaker 132 is switched from a closed state to an open state, it is possible to manually switch the main breaker 132 from an open state to a closed state to make the main circuit 11 conductive.

[0025] The main breaker 132 controls the supply of power from the power system 2 to the multiple outlets 3 by switching between an open state and a closed state. Note that the above "controlling the supply of power" includes supplying and stopping power. More specifically, the above "controlling the supply of power" includes, as described above, the case where the main circuit 11 is turned on and off depending on whether the current flowing in the main circuit 11 is an abnormal current (overcurrent or leakage current).

[0026] The leakage current detection circuit 132a operates (i.e., starts up) using as its operating voltage the voltage from the power system 2 supplied through the main electric circuit 11. In this embodiment, the leakage current detection circuit 132a operates using as its operating voltage the voltage between the L1-phase electric circuit and the L2-phase electric circuit of the main electric circuit 11 (i.e., 200 V). Therefore, in this embodiment, as will be described later, the output voltage (100 V) of the distributed power source 4 and the applied voltage (e.g., 100 V) at the time of detecting continuity in the power distribution system 1 are insufficient to provide an operating voltage, and therefore the leakage current detection circuit 132a does not operate.

[0027] The branch breakers 133 correspond one-to-one to the branch electric circuits 12 and are provided in the corresponding branch electric circuits 12. The branch breakers 133 switch between an open state and a closed state depending on whether the amount of current flowing through the corresponding branch electric circuit 12 satisfies a predetermined condition, and conduct or cut off the corresponding branch electric circuit 12 depending on the closed state and the open state. The predetermined condition is, for example, a condition that a current of a predetermined value (e.g., 20 A) flows through the branch electric circuit 12 for a predetermined time (e.g., one hour). The branch breakers 133 conduct or cut off the power transmitted to the multiple outlets 3 for each outlet 3. Note that when the branch breaker 133 cuts off the branch electric circuit 12, it means that it cuts off all two electric circuits constituting the branch electric circuit 12, and when the branch breaker 133 conducts the branch electric circuit 12, it means that it makes all two electric circuits constituting the branch electric circuit 12 conductive.

[0028] The plurality of ground terminals 134 are terminals used when grounding an E-phase pole (ground pole) of each outlet 3, which will be described later. Each of the plurality of ground terminals 134 is grounded to a ground point A2. The electrical resistance at the ground point A2 is, for example, 100Ω or less. The E-phase pole of each outlet 3 is connected to the ground terminal 134 via an electric path. The E-phase pole of each outlet 3 is connected to the ground terminal 134, and thereby grounded to the ground point A2.

[0029] The smart meter 14 is provided between the pole transformer 6 and the distribution board 13 in the main electric circuit 11. The smart meter 14 measures the power transmitted from the pole transformer 6 to the distribution board 13 (i.e., the power consumed by the electrical devices 5 in the building). The measurement results of the smart meter 14 can be transmitted to, for example, a power company.

[0030] The multiple outlets 3 are installed inside or outside the building. The multiple outlets 3 are receptacles into which power plugs of electrical devices 5 are inserted, and supply power to the electrical devices 5 via the inserted power plugs. The electrical devices 5 are, for example, lighting fixtures, refrigerators, televisions, etc.

[0031] At least one of the multiple outlets 3 is a three-pole outlet. A three-pole outlet is an outlet having three outlets. A three-pole outlet is an outlet having three sockets corresponding to the three blades (L-phase, N-phase, and E-phase (ground)) of a three-pole plug. A three-pole outlet may further have a two-pole outlet. A two-pole outlet is an outlet having only two sockets corresponding to the two blades (L-phase and N-phase) of a two-pole plug. In this embodiment, of the multiple outlets 3, the outlet 3a is a three-pole outlet, and the remaining outlets 3b and 3c are two-pole outlets. A two-pole outlet is an outlet having only two-pole outlets. All of the multiple outlets 3 may be three-pole outlets.

[0032] In this embodiment, for example, all of the outlets 3c on the L1 side are two-pole outlets. Of the outlets 3 on the L2 side, only the outlet 3a is a three-pole outlet, and the remaining outlets 3b are two-pole outlets. The L-phase pole and the N-phase pole of the two-pole outlet 3c on the L1 side are connected to the L1-phase circuit and the N-phase circuit of the main circuit 11 through two electric circuits of the branch electric circuit 12, respectively. Of the three poles of the three-pole outlet 3a on the L2 side, the L-phase pole and the N-phase pole are connected to the L2-phase circuit and the N-phase circuit of the main circuit 11 through two electric circuits of the branch electric circuit 12, respectively, and the E-phase pole is connected to the ground terminal 134 through the electric circuit 16. The L-phase pole and the N-phase pole of the two-pole outlet 3b on the L2 side are connected to the L2-phase circuit and the N-phase circuit of the main circuit 11 through two electric circuits of the branch electric circuit 12, respectively.

[0033] The multiple outlets 3 include indoor outlets and outdoor outlets. An outdoor outlet is an outlet installed outdoors (for example, on an exterior wall) of a building, and in this embodiment, the three-prong outlet 3a is the outdoor outlet. An indoor outlet is an outlet installed inside a building, and in this embodiment, the outlets 3b and 3c are the indoor outlets. Note that all of the multiple outlets 3 may be indoor outlets or outdoor outlets.

[0034] In this grid power distribution system 10, power (e.g., 6600V) from the power grid 2 is stepped down to a predetermined power (e.g., 100V / 200V, 15A) by the pole transformer 6, and then transmitted to the distribution board 13 through the main circuit 11. The power transmitted to the distribution board 13 passes through a main breaker 132 and is then distributed to a plurality of outlets 3 through a plurality of branch circuits 12. Each outlet 3 can output power of a predetermined standard (e.g., 100V, 15A). The power transmitted to each outlet 3 is supplied to an electric device 5 connected to the outlet 3. The leakage detection circuit 132a of the main breaker 132 operates using the voltage applied to the main circuit 11 as its operating power source, and detects leakage of the current flowing through the main circuit 11. When the leakage detection circuit 132a detects leakage, it switches the main breaker 132 from a closed state to an open state to cut off the main circuit 11. This interruption stops the supply of power from the power system 2 to the multiple outlets 3. It is possible to resume the supply of power from the power system 2 to the multiple outlets 3 by manually switching the main breaker 132 from an open state to a closed state.

[0035] In this embodiment, the power distribution system 1 and the distributed power sources 4 configure a power supply system 70 that supplies power to a grid power distribution system 10 installed in a building.

[0036] Next, the distributed power source 4 will be described in detail with reference to FIG.

[0037] The distributed power source 4 is a power source that outputs AC power and is a power source other than the power system 2. The distributed power source 4 is, for example, a backup power source for the power system 2. A backup power source is a power source that supplies AC power instead of the power system 2 when the power system 2 cannot be used. The distributed power source 4 is, for example, a generator or a solar power generator. The generator is a generator that uses gasoline, LP gas, or the like as fuel. The distributed power source 4 may also be a power output unit (for example, an AC 100V outlet) provided on a hybrid vehicle, an electric vehicle, or the like. The distributed power source 4 has an output unit 4a that outputs power. The output unit 4a is a female type output unit (i.e., a structure having a socket into which a plug is inserted). The output unit 4a is a three-pole output unit having three individual sockets.

[0038] Next, the relay cable 60 will be described in detail with reference to FIG.

[0039] The relay cable 60 is a cable that relays between the power receiving outlet 3a of the power distribution system 10 and the output unit 4a of the distributed power source 4. The relay cable 60 includes two plugs (an input plug 20 and an output plug 21) and a cable 22.

[0040] The input plug 20 is connected to the output section 4a of the distributed power source 4, and inputs the power output from the distributed power source 4. The output plug 21 is connected to the power receiving outlet 3a, and outputs the power from the distributed power source 4 input to the input plug 20 to the power receiving outlet 3a. The two plugs 20, 21 are each a male plug and a three-pole plug. A three-pole plug has three blades (L-phase, N-phase, and E-phase). The three poles of the input plug 20 are connected to the three poles of the outlet 3 so that the same phase poles are connected to each other. The three poles of the output plug 21 are connected to the three poles of the output section 4a of the distributed power source 4 so that the same phase poles are connected to each other. The two plugs 20, 21 are each connected via a cable 22. The input plug 20 is connected to the output section 4a of the distributed power source 4, and the output plug 21 is connected to the power receiving outlet 3a. As a result, the relay cable 60 relays between the power receiving outlet 3a and the output section 4a of the distributed power source 4.

[0041] In this embodiment, the distributed power source 4 is assumed to be a commercially available distributed power source, and therefore the output section 4a of the distributed power source 4 is a female type. Therefore, when connecting the output section 4a of the distributed power source 4 to the power receiving outlet 3a, a relay cable 60 is used. The distributed power source 4 is not limited to a commercially available distributed power source, and may be a distributed power source whose output section 4a has a male plug.

[0042] Next, the power distribution system 1 will be described in detail with reference to FIG.

[0043] First, the main features (feature 1 and feature 2) of the power distribution system 1 will be described.

[0044] In the power distribution system 1, the distributed power source 4 is connected to the power receiving outlet 3a via, for example, a relay cable 60, so that the power from the distributed power source 4 can be supplied to another outlet 3b among the multiple outlets 3. The power receiving outlet 3a is a three-pole outlet including an E-phase pole (ground pole) for the purpose of controlling the opening and closing of the main breaker 132 by the power distribution system 1 as described later. In this embodiment, the power receiving outlet 3a is an outdoor outlet.

[0045] In the following description, the time when the dispersed power source 4 is connected to the power receiving outlet 3a via the relay cable 60 is also simply referred to as "when the dispersed power source 4 is connected." Additionally, the state in which the dispersed power source 4 is connected to the power receiving outlet 3a via the relay cable 60 is also simply referred to as "the connection state of the dispersed power source 4."

[0046] (Feature 1) The power distribution system 1 supplies power from the distributed power source 4 to the other outlet 3b via the distribution board 13 only when the distributed power source 4 is connected and in the connected state and the main breaker 132 is in the open state. This makes it possible to prevent power from the distributed power source 4 from being fed back into the power grid 2 even if the main breaker 132 is in the closed state when the distributed power source 4 is connected and even if the main breaker 132 is manually switched from the open state to the closed state while the distributed power source 4 is connected.

[0047] (Feature 2) If the main breaker 132 is in a closed state when and in a connected state of the distributed power source 4, the power distribution system 1 controls the main breaker 132 to be forcibly changed from a closed state to an open state. This makes it possible to prevent reverse flow of power from the distributed power source 4 to the power grid 2 even if the main breaker 132 is in a closed state when the distributed power source 4 is connected, or even if the main breaker 132 is manually switched from an open state to a closed state while the distributed power source 4 is connected.

[0048] Next, the configuration of the power distribution system 1 will be described in detail with reference to FIGS.

[0049] The power distribution system 1 is connected to the middle of a branch circuit 12 to which a power receiving outlet 3a is connected. The power distribution system 1 is also connected to the middle of an electric circuit 16 connected to a ground terminal 134. The power distribution system 1 outputs power from a distributed power source 4 input to the power receiving outlet 3a to a branch circuit 131 through the branch circuit 12. As a result, power from the distributed power source 4 is supplied from the branch circuit 131 to another outlet 3b.

[0050] The power distribution system 1 includes three first input / output units 71a-71c, three second input / output units 70a-70c, a main circuit 23, an electromagnetic contactor 24 (second contactor), a continuity detection unit 25, a pseudo-earth leakage circuit 26, two voltage detection units (a first voltage detection unit 28 and a second voltage detection unit 29 (connection detection unit)), a power supply unit 30, and a control unit 32.

[0051] The three second input / output units 70a to 70c are respectively connected to three poles (L-phase pole, N-phase pole, and E-phase pole) of the power receiving outlet 3a via electric circuits (two branch electric circuits 12 and one electric circuit 16). The first input / output units 71a and 71b are connected to a branch breaker 133 via two branch electric circuits 12. The first input / output unit 71c is connected to a ground terminal 134 via the electric circuit 16.

[0052] The main electric circuit 23 is an electric circuit that connects the second input / output units 70a to 70c and the first input / output units 71a to 71c (see FIG. 2). The main electric circuit 23 is composed of three electric circuits (an L-phase electric circuit, an N-phase electric circuit, and an E-phase electric circuit). One end of each of the three electric circuits of the main electric circuit 23 is connected to the three second input / output units 70a to 70c. That is, one end of each of the three electric circuits of the main electric circuit 23 is connected to the three electric circuits from the power receiving outlet 3a via the second input / output units 70a to 70c, with the L-phases connected to each other, the N-phases connected to each other, and the E-phases connected to each other. The other end of each of the three electric circuits of the main electric circuit 23 is connected to the first input / output units 71a to 71c. That is, the other ends of the two electric circuits (L-phase and N-phase) of the main electric circuit 23 are connected to the two branch electric circuits 12 from the branch breaker 133 via the first input / output units 71a, 71b, with the L-phase and the N-phase connected. The other end of the E-phase electric circuit of the main electric circuit 23 is connected to the electric circuit 16 from the ground terminal 134 via the first input / output unit 71c.

[0053] The electromagnetic switch 24 (second switch) can be switched between a closed state and an open state, and connects or disconnects the main electric circuit 23 depending on whether the switch is closed or open. This connection and disconnection provides connection and disconnection between the second input / output units 70a-70c and the first input / output units 71a-71c. More specifically, the electromagnetic switch 24 connects or disconnects two of the three electric circuits (the L-phase electric circuit and the N-phase electric circuit) that constitute the main electric circuit 23 individually depending on whether the switch is closed or open.

[0054] When the main breaker 132 is in an open state and power from the distributed power source 4 connected to the power receiving outlet 3a (one outlet) is being supplied to another outlet 3b other than the power receiving outlet 3a among the multiple outlets 3, the electromagnetic switch 24 controls the supply of power from the distributed power source 4 to the other outlet 3b in place of the main breaker 132 (first switch). The electromagnetic switch 24 controls the supply of power from the distributed power source 4 to the other outlet 3b by switching between an open state and a closed state.

[0055] The above phrase "controlling the supply of power" includes supplying and stopping power. Note that when the electromagnetic switch 24 detects an abnormal current (earth leakage current, arc current, or overcurrent) and switches between an open state and a closed state of the electromagnetic switch 24 depending on the detection result, such switching may be included in the above phrase "controlling the supply of power." Also, the above phrase "instead of the main breaker 132" has the following meaning. That is, when the main breaker 132 is in an open state, the power supplied from the distributed power source 4 connected to the power receiving outlet 3a to the other outlet 3b does not flow through the main breaker 132, and therefore cannot be controlled by the main breaker 132. For this reason, the above phrase means that the electromagnetic switch 24 controls the supply of power instead of the main breaker 132.

[0056] The continuity detection unit 25 detects whether the main breaker 132 is open or not based on the continuity of the electric circuit (in other words, the electric circuit including the main electric circuit 11) passing through the main breaker 132 when the distributed power source 4 is connected and in the connected state. More specifically, the continuity detection unit 25 detects the continuity of the electric circuit based on the impedance between the N-phase electric circuit and the E-phase electric circuit of the main electric circuit 23 between the first input / output units 71a to 71c and the electromagnetic switch 24 when the distributed power source 4 is connected and in the connected state. Note that in this embodiment, detecting the impedance between the N-phase electric circuit and the E-phase electric circuit of the main electric circuit 23 is the same as detecting the impedance between the two first input / output units 71b, 71c.

[0057] The pseudo earth leakage circuit 26 causes a pseudo earth leakage current to flow through the main circuit 23 of the power distribution system 1 when the main breaker 132 is in a closed state while the distributed power source 4 is connected. This causes a pseudo earth leakage current to flow through the main circuit 11 (the circuit passing through the main breaker 132) of the distribution board 13. The pseudo earth leakage circuit 26 causes the earth leakage detection circuit 132a of the main breaker 132 to detect the pseudo earth leakage, thereby forcibly controlling the main breaker 132 to change from a closed state to an open state.

[0058] When the distributed power source 4 is connected, the pseudo earth leakage circuit 26 generates a pseudo earth leakage in the current flowing through the main electric circuit 23 by shorting the L-phase electric circuit and the E-phase electric circuit of the main electric circuit 23 between the first input / output units 71a to 71c and the electromagnetic switch 24. The pseudo earth leakage circuit 26 includes a relay 26a and a resistor 26b. The relay 26a and the resistor 26b are connected in series with each other and between the L-phase electric circuit and the E-phase electric circuit of the main electric circuit 23. The L-phase electric circuit and the E-phase electric circuit are connected or disconnected depending on the closed state and open state of the relay 26a, and the L-phase electric circuit and the E-phase electric circuit are short-circuited due to the conduction.

[0059] The first voltage detection unit 28 detects whether or not the voltage input to the first input / output units 71a, 71b (i.e., the voltage from the power system 2) exceeds a predetermined voltage (for example, 0 V). More specifically, the first voltage detection unit 28 detects whether or not the voltage between the L-phase electric circuit and the N-phase electric circuit of the main electric circuit 23 between the electromagnetic switch 24 and the first input / output units 71a to 71c is equal to or higher than a predetermined voltage when the electromagnetic switch 24 is in an open state. This makes it possible to detect whether the power system 2 is experiencing a power outage or has been restored. That is, when the voltage detected by the first voltage detection unit 28 is equal to or lower than the predetermined voltage, it is determined that the power system 2 is experiencing a power outage, and when the voltage detected by the first voltage detection unit 28 exceeds the predetermined voltage, it is determined that the power system 2 is supplying power (including power restoration).

[0060] The second voltage detection unit 29 (connection detection unit) detects whether or not the voltage input to the second input / output units 70a, 70b (i.e., the voltage from the power receiving outlet 3a) exceeds a specified voltage. More specifically, the second voltage detection unit 29 detects whether or not the voltage between the L-phase circuit and the N-phase circuit of the main circuit 23 between the electromagnetic switch 24 and the second input / output units 70a, 70b exceeds a specified voltage when the electromagnetic switch 24 is in an open state. This makes it possible to determine whether or not the distributed power source 4 is connected to the power receiving outlet 3a (i.e., whether the distributed power source 4 is connected or in a connected state). That is, if the detected voltage of the second voltage detection unit 29 exceeds the specified voltage, it is determined that the distributed power source 4 is connected to the power receiving outlet 3a, and if the detected voltage of the second voltage detection unit 29 is equal to or lower than the specified voltage, it is determined that the distributed power source 4 is not connected to the power receiving outlet 3a. Note that the cases where it is determined that the distributed power source 4 is not connected to the power receiving outlet 3a include cases where an electric device 5 is connected to the power receiving outlet 3a.

[0061] In this embodiment, each detection unit (continuity detection unit 25, first voltage detection unit 28, and second voltage detection unit 29) performs the above detection at regular intervals while the dispersed power source 4 is connected. By setting the regular intervals to a relatively short interval (e.g., 1 second), each detection unit can effectively perform the above detection promptly when the dispersed power source 4 is connected.

[0062] The power supply unit 30 functions as a power supply for the power distribution system 1. The power supply unit 30 steps down the output voltage of the distributed power source 4 input to the second input / output units 70a to 70c to a predetermined voltage, and sets it as the operating voltage of the power distribution system 1.

[0063] The control unit 32 controls the electromagnetic switch 24 and the pseudo earth leakage circuit 26 according to the detection results of the respective detection units (continuity detection unit 25, first voltage detection unit 28, and second voltage detection unit 29).

[0064] More specifically, when the main breaker 132 is in a closed state and no distributed power source 4 is connected to the power receiving outlet 3a, the control unit 32 controls the electromagnetic switch 24 to change from an open state to a closed state. This causes power from the power grid 2 to be supplied to the power receiving outlet 3a via the power distribution system 1. As a result, the power receiving outlet 3a can be used as a normal power outlet. That is, when an electric device 5 is connected to the power receiving outlet 3a, power is supplied from the power receiving outlet 3a to the electric device 5.

[0065] Furthermore, when the conductive detection unit 25 detects that the main breaker 132 is in a closed state when the distributed power source 4 is connected or in a connected state, the control unit 32 controls the electromagnetic switch 24 to change from a closed state to an open state. This interrupts the main electric circuit 23 of the power distribution system 1. Therefore, power from the distributed power source 4 is prohibited from being output to the distribution board 13 through the power distribution system 1. As a result, reverse flow of power from the distributed power source 4 to the power system 2 is prevented. In this way, the control unit 32 controls the opening and closing of the electromagnetic switch 24, thereby controlling the output (transmission) of power from the distributed power source 4 to the distribution board 13.

[0066] Furthermore, when the conductive detection unit 25 detects that the main breaker 132 is open when the distributed power source 4 is connected or in the connected state, the control unit 32 controls the electromagnetic switch 24 to change from the open state to the closed state. This brings about conductivity in the main circuit 23 of the power distribution system 1, and power from the distributed power source 4 is output to the distribution board 13 through the main circuit 23. In this manner, with the main breaker 132 in the open state, the control unit 32 outputs power from the distributed power source 4 to the distribution board 13. As a result, power from the distributed power source 4 is supplied from the power receiving outlet 3a to another outlet 3b through the circuit in the distribution board 13.

[0067] Furthermore, when the conductive detection unit 25 detects that the main breaker 132 is in a closed state when the distributed power source 4 is connected or in a connected state, the control unit 32 controls the pseudo earth leakage circuit 26 to be activated (i.e., the relay 26a to be changed from an open state to a closed state). This generates a pseudo earth leakage in the current flowing through the main electric circuit 11 of the distribution board 13. Then, the earth leakage detection circuit 132a of the main breaker 132 detects the pseudo earth leakage, and the main breaker 132 automatically switches from a closed state to an open state. In other words, the control unit 32 activates the pseudo earth leakage circuit 26 to generate a pseudo earth leakage, and causes the earth leakage detection circuit 132a to detect the pseudo earth leakage, thereby forcibly controlling the main breaker 132 to be changed from a closed state to an open state.

[0068] Furthermore, when the continuity detection unit 25 detects that the main breaker 132 is open when the distributed power source 4 is connected or in a connected state, the control unit 32 controls the pseudo earth leakage circuit 26 to be stopped (i.e., to maintain the relay 26a in an open state). This prevents the occurrence of a pseudo earth leakage in the current flowing through the main electric circuit 11 of the distribution board 13.

[0069] More specifically, when the distributed power source 4 is connected or in a connected state, if the continuity detection unit 25 detects that the main breaker 132 is in an open state, the control unit 32 controls the pseudo-earth leakage circuit 26 to be activated if the detected voltage of the first voltage detection unit 28 exceeds a predetermined voltage (e.g., 0 V), and controls the pseudo-earth leakage circuit 26 to be stopped if the detected voltage of the first voltage detection unit 28 is equal to or lower than the predetermined voltage.

[0070] Next, the above-mentioned feature 1 of the power distribution system 1 will be described in detail with reference to FIG.

[0071] In feature 1, the power distribution system 1 supplies power from the distributed power source 4 to another outlet 3b via the distribution board 13 only when the distributed power source 4 is connected and in a connected state and the main breaker 132 is in an open state.

[0072] More specifically, the continuity detection unit 25 detects whether or not the impedance between the N-phase electric circuit and the E-phase electric circuit of the main electric circuit 23 of the power distribution system 1 is equal to or less than a predetermined value (e.g., 200Ω) when the distributed power source 4 is connected or in a connected state. As a result, the continuity detection unit 25 detects whether or not the path T1 shown in Fig. 3 is closed, and determines (detects) whether or not the main breaker 132 is in an open state according to the detection result.

[0073] Path T1 is a path that runs from the continuity detection unit 25, in order, through branch point B2 of the N-phase circuit of the main circuit 23, the first input / output unit 71b, branch point B3 of the N-phase circuit of the main circuit 11, the N-phase side relay of the main breaker 132, branch point B1 of the N-phase circuit, ground point A1, ground point A2, ground terminal 134, the circuit 16, the first input / output unit 71c, and branch point B4 of the E-phase circuit of the main circuit 23, and returns to the continuity detection unit 25.

[0074] When the path T1 is conductive, the impedance detected by the continuity detection unit 25 is roughly the sum of the ground resistances at the two ground points A1 and A2 (for example, 110 Ω). On the other hand, when the path T1 is not conductive, the impedance detected by the continuity detection unit 25 is infinite. Therefore, when the impedance detected by the continuity detection unit 25 is equal to or less than a predetermined value (for example, 200 Ω), the continuity detection unit 25 determines that the path T1 is conductive (i.e., the main breaker 132 is in a closed state). When the impedance detected by the continuity detection unit 25 exceeds the predetermined value, the continuity detection unit 25 determines that the path T1 is not conductive (i.e., the main breaker 132 is in an open state).

[0075] More specifically, the continuity detection unit 25 applies a predetermined voltage (a voltage of about several volts) between the N-phase electric circuit and the E-phase electric circuit of the main electric circuit 23 of the power distribution system 1. The continuity detection unit 25 detects a current flowing between the N-phase electric circuit and the E-phase electric circuit when the voltage is applied. The continuity detection unit 25 detects whether the impedance between the N-phase electric circuit and the E-phase electric circuit of the main electric circuit 23 is equal to or lower than a predetermined value (i.e., whether the electric circuits 11, 23 passing through the main breaker 132 are conductive) based on the detected current. Note that, during this detection, it is desirable that the electromagnetic switch 24 is controlled to an open state by the control unit 32.

[0076] The earth leakage detection circuit 132a of the main breaker 132 is activated by the voltage (200V) between the L1-phase circuit and the L2-phase circuit of the main circuit 11 in the distribution board 13. For this reason, the earth leakage detection circuit 132a is not activated by the voltage applied at the time of detection by the continuity detection unit 25 and the output voltage of the distributed power source 4.

[0077] Furthermore, since the detection by the conductivity detection unit 25 is repeated at relatively short regular intervals (for example, one second intervals), when the main breaker 132 is manually switched from an open state to a closed state, the closed state of the main breaker 132 can be quickly detected.

[0078] If the main breaker 132 is in the closed state, assuming that the electromagnetic switch 24 is in the closed state, there is a possibility that the power from the distributed power source 4 will flow back to the power system 2 in the connection state of the distributed power source 4. For this reason, in this case, the electromagnetic switch 24 is maintained in the open state by the control unit 32. As a result, in the connection state of the distributed power source 4, the power from the distributed power source 4 is blocked from being supplied to the other outlet 3b via the distribution board 13. On the other hand, if the main breaker 132 is in the open state, even if the electromagnetic switch 24 is in the closed state in the connection state of the distributed power source 4, there is no possibility that the power from the distributed power source 4 will flow back to the power system 2. For this reason, in this case, the electromagnetic switch 24 is controlled by the control unit 32 from the open state to the closed state. As a result, in the connection state of the distributed power source 4, the power from the distributed power source 4 is supplied to the other outlet 3b via the distribution board 13.

[0079] Next, the above feature 2 of the power distribution system 1 will be described in detail with reference to FIG.

[0080] In feature 2, when the distributed power source 4 is connected and in the connected state, if the main breaker 132 is in the closed state, the power distribution system 1 controls the main breaker 132 to be forcibly changed from the closed state to the open state.

[0081] For example, when the main breaker 132 is manually switched from an open state to a closed state during power supply from the power system 2 (including after power is restored), the leakage current detection circuit 132a of the main breaker 132 is activated. In this case, the pseudo earth leakage circuit 26 of the power distribution system 1 generates a pseudo earth leakage current flowing through the path T2 (i.e., the electric path via the main breaker 132) shown in FIG. 4, and causes the leakage current detection circuit 132a to detect this pseudo earth leakage current. When the leakage current detection circuit 132a detects the pseudo earth leakage current, the main breaker 132 is automatically switched from a closed state to an open state. In this way, when the leakage current detection circuit 132a is activated, the power distribution system 1 controls the main breaker 132 to be forcibly changed from a closed state to an open state by generating a pseudo earth leakage current using the pseudo earth leakage circuit 26 and causing the leakage current detection circuit 132a to detect the pseudo earth leakage current.

[0082] In addition, path T2 is a path that runs from the lower end B5 of the secondary coil of the pole transformer 6, in this order, to branch point B6 of the L2 phase circuit of the main electric circuit 11, the L side electric circuit of the branch electric circuit 12 connected to branch point B6, the first input / output unit 71a, branch point B7 of the L phase electric circuit of the main electric circuit 23 of the power distribution system 1, resistor 26b, relay 26a, branch point B8 of the E phase electric circuit of the main electric circuit 23, the first input / output unit 71c, the electric circuit 16, ground terminal 134, ground point A2, ground point A1, branch point B1 of the N phase electric circuit of the main electric circuit 11, the center point of the secondary coil 62, and the lower end B5 of the secondary coil 62.

[0083] More specifically, in this embodiment, when the distributed power source 4 is connected and in the connected state, the continuity detection unit 25 detects that the main breaker 132 is in the closed state. Then, in response to this detection result, the control unit 32 controls the pseudo earth leakage circuit 26 to be activated (i.e., to change the relay 26a from the open state to the closed state).

[0084] In this embodiment, as described above, the pseudo earth leakage circuit 26 is activated (operated) according to the detection result of the continuity detection unit 25. However, the pseudo earth leakage circuit 26 may be operated all the time regardless of the detection result of the continuity detection unit 25. That is, the relay 26a may be maintained in a closed state all the time. In this case, when the main breaker 132 is switched from an open state to a closed state during power supply from the power system 2 (including after power recovery) with the distributed power source 4 connected and the electromagnetic switch 24 in a closed state, power supply from the power system 2 and power supply from the distributed power source 4 are performed in parallel. However, when the leakage detection circuit 132a detects a pseudo earth leakage caused by the pseudo earth leakage circuit 26, the main breaker 132 is quickly switched from a closed state to an open state, and the power supply from the power system 2 is cut off.

[0085] In the above case (i.e., when the relay 26a is maintained in a normally closed state and the electromagnetic switch 24 is in a closed state), the potential of the E-phase electric circuit of the main electric circuit 23 of the power distribution system 1 may rise. For this reason, it is desirable to set the value of the resistor 26b so that the potential of the E-phase electric circuit does not exceed a specified potential.

[0086] It is preferable that the relay 26a of the pseudo earth leakage circuit 26 is controlled to an open state when the electromagnetic switch 24 is in an open state.

[0087] Next, the operation of the power distribution system 1 will be described with reference to the flowchart of Fig. 5. In the following description, Sn (n = 1, 2, ...) indicates each step in the flowchart of Fig. 5.

[0088] A power outage occurs in the power system 2 (Yes in S1). In this situation, the user manually switches the main breaker 132 from a closed state to an open state (S2), or leaves the main breaker 132 in a closed state (S3), and then connects the distributed power source 4 to the power receiving outlet 3a via the relay cable 60 (S4). Then, after the distributed power source 4 is connected, the user starts up the distributed power source 4 (S5). As a result, power (voltage) from the distributed power source 4 is input to the power receiving outlet 3a. Then, based on this input voltage, the second voltage detection unit 29 of the power distribution system 1 detects that the distributed power source 4 is connected to the power receiving outlet 3a (S6). More specifically, the second voltage detection unit 29 detects whether or not the voltage between the second input / output units 70a, 70b (i.e., the voltage between the L-phase electric circuit and the N-phase electric circuit of the main electric circuit 23) exceeds a specified voltage when the electromagnetic switch 24 is in an open state. The second voltage detection unit 29 detects that the voltage between the second input / output units 70a, 70b exceeds a specified voltage, thereby detecting that the dispersed power source 4 is connected to the power receiving outlet 3a.

[0089] Then, the continuity detection unit 25 of the power distribution system 1 detects whether the main breaker 132 is in an open state based on the impedance between the N-phase circuit and the E-phase circuit of the main circuit 23 of the power distribution system 1 (S7). If the result of this detection is that the main breaker 132 is in an open state (Yes in S7), the control unit 32 of the power distribution system 1 controls the electromagnetic switch 24 to change from an open state to a closed state (S8). As a result, the power from the distributed power source 4 is output to the distribution board 13 via the power distribution system 1. As a result, the power from the distributed power source 4 flows from the power receiving outlet 3a through the electric circuit inside the distribution board 13 and is supplied to the other outlet 3b. As a result, the power from the distributed power source 4 is supplied to the electric device 5 connected to the other outlet 3b. In this way, even during a power outage in the power system 2, the electric device 5 can be connected to the other outlet 3b and used.

[0090] Then, the second voltage detection unit 29 of the power distribution system 1 detects whether the distributed power source 4 is connected to the power receiving outlet 3a (in other words, whether the distributed power source 4 is removed from the power receiving outlet 3a) (S9). Then, when the user removes the distributed power source 4 from the power receiving outlet 3a, the second voltage detection unit 29 detects the removal (Yes in S9). At this time, if the continuity detection unit 25 of the power distribution system 1 detects the main breaker 132 in a closed state (Yes in S10), the control unit 32 controls the electromagnetic switch 24 to be in a closed state (S11). This allows power from the power system 2 to be output to the power receiving outlet 3a via the power distribution system 1, and the power receiving outlet 3a can be used as a power outlet. This allows the electrical device 5 to be connected to the power receiving outlet 3a and used when the power system 2 is restored (power restored). Then, the process ends.

[0091] On the other hand, if the continuity detection unit 25 detects that the main breaker 132 is open in step S10 (No in S10), the process returns to step S4, and the processes from step S4 onward are executed. On the other hand, if the distributed power source 4 has not been removed from the power receiving outlet 3a in step S9 (No in S9), the process returns to step S7, and the processes from step S7 onward are executed.

[0092] On the other hand, if the detection result in step S7 shows that the main breaker 132 is not in the open state (i.e., in the closed state) (No in S7), the control unit 32 of the power distribution system 1 controls the electromagnetic switch 24 to change from the closed state to the open state (S12). This blocks the output of power from the distributed power source 4 from the power receiving outlet 3a to the distribution board 13. As a result, it is possible to prevent the power from the distributed power source 4 from flowing back to the power system 2 through the main breaker 132.

[0093] Then, the control unit 32 of the power distribution system 1 detects whether the detection result of the first voltage detection unit 28 (the voltage between the first input / output units 71a and 71b) exceeds a predetermined value (S13). Then, when the voltage detected by the first voltage detection unit 28 exceeds the predetermined value (Yes in S13), the control unit 32 determines that the power system 2 is supplying power (including after power recovery) and the leakage detection circuit 132a of the main breaker 132 is activated, and activates the pseudo earth leakage circuit 26. That is, the control unit 32 controls the relay 26a to change from an open state to a closed state (S14). As a result, a pseudo earth leakage occurs in the current flowing through the path T2 shown in FIG. 3, and the leakage detection circuit 132a detects the pseudo earth leakage and controls the main breaker 132 to change from a closed state to an open state. After that, the process proceeds in order to S7 and S8, and the power from the distributed power source 4 is supplied to another outlet 3b. By opening the main breaker 132 in step S14, reverse flow of power from the distributed power sources 4 to the power grid 2 via the main breaker 132 is prevented.

[0094] Also, in step S1, if no power outage has occurred (No in S1), the main breaker 132 is in the closed state, and therefore the control unit 32 of the power distribution system 1 maintains the main breaker 132 in the closed state (S15). Then, the second voltage detection unit 29 of the power distribution system 1 detects whether or not the distributed power source 4 is connected to the power receiving outlet 3a. As a result, if the distributed power source 4 is connected to the power receiving outlet 3a (Yes in S16), the process returns to step S12, and the process from step S12 onward is executed. On the other hand, if the distributed power source 4 is not connected to the power receiving outlet 3a (No in S16), the control unit 32 controls the electromagnetic switch 24 to change from the open state to the closed state (S17). This allows power from the power system 2 to be output to the power receiving outlet 3a via the power distribution system 1, and the power receiving outlet 3a can be used as a power outlet. This allows the electric device 5 to be connected to the power receiving outlet 3a and used. The process ends.

[0095] In this way, when the main breaker 132 is switched from an open state to a closed state (S12), if the voltage detected by the first voltage detection unit 28 exceeds the predetermined value (Yes in S13), the electric power system 2 is supplying power (including after power is restored) and the leakage current detection circuit 132a of the main breaker 132 is activated by the voltage from the electric power system 2. For this reason, the control unit 32 activates the pseudo earth leakage circuit 26 to pass a pseudo earth leakage current, thereby utilizing the function of the leakage current detection circuit 132a of the main breaker 132 to forcibly control the main breaker 132 to be changed from an open state to a closed state.

[0096] Then, the process returns from step S14 to step S7, and the processes after step S7 are executed. As a result, when the continuity detection unit 25 of the power distribution system 1 detects that the main breaker 132 is in the open state (Yes in S7), the control unit 32 of the power distribution system 1 controls the electromagnetic switch 24 to change from the open state to the closed state (S8). This prevents the power from the distributed power source 4 from being fed back to the power grid 2, and the power from the distributed power source 4 is supplied to another outlet 3b via the power distribution system 1 and the distribution board 13.

[0097] On the other hand, in step S13, if the voltage detected by the first voltage detection unit 28 is equal to or lower than the predetermined value (No in S13), the control unit 32 determines that the power system 2 is experiencing a power outage (i.e., power has not been restored). That is, the control unit 32 determines that the switching of the main breaker 132 from the open state to the closed state in step S7 is an erroneous operation by the user. Then, the process returns to step S2, and the processes from step S2 onwards are executed. As a result, after the user manually switches the main breaker 132 from the closed state to the open state (S2), the control unit 32 of the power distribution system 1 controls the electromagnetic switch 24 from the open state to the closed state (S8) through each process (S4 to S7). As a result, the power from the distributed power source 4 is prevented from being fed back to the power system 2, and the power from the distributed power source 4 is supplied to another outlet 3b via the power distribution system 1 and the distribution board 13.

[0098] (Major Effects) As described above, the power distribution system 1 of the present embodiment includes an electromagnetic switch 24 (second switch). The electromagnetic switch 24 is provided between the main breaker 132 (first switch) and the power receiving outlet 3a in an electric circuit that connects the power system 2 and the multiple outlets 3 and in which the main breaker 132 is provided between the power system 2 and the multiple outlets 3. The power receiving outlet 3a is one of the multiple outlets 3. When the main breaker 132 is in an open state and power from the distributed power source 4 connected to the power receiving outlet 3a is supplied to another outlet 3b of the multiple outlets 3 other than the power receiving outlet 3a, the electromagnetic switch 24 controls the supply of power from the distributed power source 4 to the other outlet 3b.

[0099] According to this configuration, when the main breaker 132 is open due to a power outage or the like, the other outlet 3b can be used as a power outlet in the same way as when there is no power outage by connecting the distributed power source 4 to the power receiving outlet 3a and supplying power from the distributed power source 4 to the other outlet 3b. At that time, the supply of power from the distributed power source 4 to the other outlet 3b can be controlled by the electromagnetic switch 24. This makes it possible to prevent accidents caused by abnormal current such as electric leakage.

[0100] (Modification) Modifications of the above embodiment will be described. The modifications described below can be applied in appropriate combination.

[0101] (Variation 1) Although not specifically described in the above embodiment, the power receiving outlet 3a has a housing and accommodates various components (such as three poles) in the housing. The distribution board 13 also has a housing and accommodates various components (such as an open / close contact and a leakage detection circuit 132a) in the housing. In the above embodiment, at least the electromagnetic switch 24 in the power distribution system 1 may be accommodated in the same housing as the power receiving outlet 3a (first outlet), or may be accommodated in the same housing as the main breaker 132 (first breaker). This allows at least the electromagnetic switch 24 in the power distribution system 1 to be built into the power receiving outlet 3a or the main breaker 132.

[0102] (Variation 2) In the above embodiment, the power receiving outlet 3a can be connected to both the distributed power source 4 and the electrical device 5. That is, when an electrical device 5 is connected to the power receiving outlet 3a during a non-power outage (when the main breaker 132 is closed), the power receiving outlet 3a can be used as a power outlet that supplies power to the electrical device 5. On the other hand, when a distributed power source 4 is connected to the power receiving outlet 3a during a power outage (when the main breaker 132 is open), power from the distributed power source 4 is supplied from the power receiving outlet 3a to the other outlet 3b, making it possible to use the other outlet 3b as a power outlet.

[0103] However, the power receiving outlet 3a may be an outlet dedicated to the distributed power source to which only the distributed power source 4 is connected. In this case, when the main breaker 132 is in a closed state (when there is no power outage), the electromagnetic switch 24 is always controlled to an open state by the control unit 32. That is, in this case, the control of the electromagnetic switch 24 is simplified. In this way, when the main breaker 132 is in a closed state (when there is no power outage), the electromagnetic switch 24 is always controlled to an open state by the control unit 32. This makes it possible to prevent reverse power flow from the distributed power source 4 even if the distributed power source 4 is connected to the power receiving outlet 3a when the main breaker 132 is in a closed state (when there is no power outage). However, in this case, even if an electric device 5 is connected to the power receiving outlet 3a when there is no power outage, power is not supplied from the power receiving outlet 3a to the electric device 5. For this reason, when the power receiving outlet 3a is used as an outlet dedicated to the distributed power source, the power receiving outlet 3a cannot be used as a power outlet when there is no power outage.

[0104] (Variation 3) In the above embodiment, the continuity detection unit 25 detects whether the main breaker 132 is in an open state based on whether the impedance between the first input / output units 71b and 71c (i.e., the impedance between the N-phase pole and the E-phase pole of the main electric circuit 23) exceeds a predetermined value. However, the continuity detection unit 25 may detect whether the main breaker 132 is in an open state based on whether the impedance between the first input / output units 71a and 71c (i.e., the impedance between the L-phase pole and the E-phase pole of the main electric circuit 23) exceeds a predetermined value. The continuity detection unit 25 may also detect whether the main breaker 132 is in an open state based on whether the impedance between the first input / output units 71a and 71b (i.e., the impedance between the L-phase pole and the N-phase pole of the main electric circuit 23) exceeds a predetermined value.

[0105] (Variation 4) In the above embodiment, the continuity detection unit 25 detects whether the main breaker 132 is in an open state based on whether the impedance between the first input / output units 71b and 71c (i.e., the impedance between the N-phase pole and the E-phase pole of the main electric circuit 23) exceeds a predetermined value. However, as shown in FIG. 6, the grid power distribution system 10 may include a detector 40 (external device) that detects whether the main breaker 132 is in an open state. In this case, the continuity detection unit 25 may obtain an opening / closing signal indicating whether the main breaker 132 is in an open state from the detector 40, and detect whether the main breaker 132 is in an open state based on the obtained opening / closing signal. In this case, the continuity detection unit 25 and the detector 40 have a communication function for communicating with each other (for example, wireless communication), and transmit and receive the above opening / closing signal using the communication function. Note that in this modification, the above communication function is assumed to perform wireless communication, but wired communication may also be performed.

[0106] (Variation 5) In the above embodiment, the continuity detection unit 25 detects whether the main breaker 132 is in an open state based on whether the impedance between the first input / output units 71b, 71c (i.e., the impedance between the N-phase pole and the E-phase pole of the main electric circuit 23) exceeds a predetermined value. However, as shown in FIG. 7, the power distribution system 1 may include an operation input unit 50 that receives input of switching information by a user. In this case, the continuity detection unit 25 may detect whether the main breaker 132 is in an open state based on the switching information input to the operation input unit 50. The above switching information is information indicating whether the main breaker 132 is in an open state. The operation input unit 50 is disposed in a place where a person can operate it, such as the surface of a wall.

[0107] (Variation 6) In the fifth modification, as shown in FIG. 7, the main electric circuit 23 of the power distribution system 1 may further include a leakage current breaker 33 (protective circuit breaker). The leakage current breaker 33 can be switched between an open state and a closed state, and interrupts and connects the main electric circuit 23 depending on the open state and the closed state. In the example of FIG. 7, the leakage current breaker 33 interrupts and connects two electric circuits (L-phase electric circuit and N-phase electric circuit) included in the main electric circuit 23. Among the main electric circuit 23, the E-phase electric circuit is a grounded wire that is grounded, and the L-phase electric circuit and the N-phase electric circuit are non-grounded wires that are not grounded wires. The leakage current breaker 33 detects a current flowing in the main electric circuit 23 (for example, the L-phase electric circuit or the N-phase electric circuit). Through this detection, the leakage current breaker 33 detects an abnormality (for example, leakage current, short circuit, and ground fault) in the branch electric circuit 12 connected to the power receiving outlet 3a (one outlet). Then, depending on the result of this detection, the earth leakage breaker 33 makes the main electric circuit 23 (electrical circuit) between the second input / output units 70a-70c and the first input / output units 71a-71c conductive or cut off. When a current less than a specified value flows through the main electric circuit 23, the earth leakage breaker 33 closes to make the main electric circuit 23 conductive, and when a current equal to or greater than a specified value (e.g., a ground fault current, an earth leakage current, or a short circuit current) flows through the main electric circuit 23, the earth leakage breaker 33 opens to cut off the main electric circuit 23.

[0108] The earth leakage breaker 33 may be manually switched between an open state and a closed state. The earth leakage breaker 33 is provided, for example, between the electromagnetic switch 24 and the first input / output units 71a to 71c in the main electric circuit 23. The earth leakage breaker 33 individually connects and disconnects the L-phase electric circuit and the E-phase electric circuit among the three electric circuits of the main electric circuit 23. The earth leakage breaker 33 can protect the internal circuit of the electric power distribution system 1 from an earth leakage current or a short-circuit current when an electric leakage or a short circuit occurs inside the grid electric power distribution system 10 with the distributed power source 4 connected.

[0109] Although this modification is applied to the modification 3 as an example, it can also be applied to the above embodiment or other modifications.

[0110] (Variation 7) In the sixth modification, the earth leakage breaker 33 (protective circuit breaker) is provided between the electromagnetic switch 24 and the first input / output units 71a to 71c in the main electric circuit 23. However, as shown in Fig. 8, the earth leakage breaker 33 may be provided between the electromagnetic switch 24 and the second input / output units 70a to 70c in the main electric circuit 23. The earth leakage breaker 33 in this modification is configured similarly to the earth leakage breaker 33 in the fourth modification.

[0111] As shown in FIG. 8, the earth leakage breaker 33 detects an abnormality (e.g., a ground fault) in the branch electric circuit 12 connected to the power receiving outlet 3a (one outlet). Then, the earth leakage breaker 33 makes the main electric circuit 23 (electric circuit) between the first input / output units 71a to 71c and the second input / output units 70a to 70c conductive or cuts off depending on the result of this detection. More specifically, the earth leakage breaker 33 detects an abnormality in the branch electric circuit 12 connected to the power receiving outlet 3a based on the current flowing in the main electric circuit 23 (e.g., an L-phase electric circuit or an N-phase electric circuit). The branch electric circuit 12 is composed of an L-phase electric circuit and an N-phase electric circuit. The earth leakage breaker 33 makes the L-phase electric circuit and the E-phase electric circuit (i.e., a ground wire) included in the main electric circuit 23 conductive or cuts off separately. When a current less than a specified value flows through the main electric circuit 23 (i.e., the earth leakage breaker 33 does not detect a ground fault current), the earth leakage breaker 33 closes to conduct the main electric circuit 23. When a current equal to or greater than a specified value flows through the main electric circuit 23 (i.e., the earth leakage breaker 33 detects a ground fault current), the earth leakage breaker 33 opens to interrupt the main electric circuit 23.

[0112] The dispersed power source 4 has a ground terminal 4b in addition to the three poles of the output section 4a (i.e., an L-phase electrode, an N-phase electrode, and an E-phase electrode) and the AC power source 4c. Of the two output terminals of the AC power source 4c, one output terminal is connected to the L-phase electrode, and the other output terminal is connected to the N-phase electrode and the E-phase electrode. The ground terminal 4b is connected to any one of the three poles of the output section 4a of the dispersed power source 4 (for example, the N-phase electrode and the E-phase electrode). The ground terminal 4b is also grounded.

[0113] Here, in a connected state of the distributed power source 4, a case is considered in which the branch electric circuit 12 (for example, an L-phase electric circuit) connected to the power receiving outlet 3a is grounded through the conductive object 200. For example, a case is considered in which the L-phase electric circuit of the branch electric circuit 12 is grounded by the conductive object 200, which is a living thing, coming into contact with the L-phase electric circuit of the branch electric circuit 12. In this case, as shown in FIG. 8, a ground fault current Ia flows from the L-phase electric circuit of the branch electric circuit 12 connected to the power receiving outlet 3a to the ground through the conductive object 200. This ground fault current Ia flows from the ground through the ground terminal 4b of the distributed power source 4 to the inside of the distributed power source 4. Then, this ground fault current Ia flows from the ground terminal 4b to one of the three electric circuits (for example, an N-phase electrode) in the distributed power source 4, flows through the relay cable 60 connected to the output unit 4a and the power receiving outlet 3a, and flows to the main electric circuit 23 (for example, an N-phase electric circuit) of the power distribution system 1. Note that the electromagnetic switch 24 is closed because power is supplied from the distributed power source 4 to the power receiving outlet 3a.

[0114] When the earth leakage breaker 33 detects a ground fault current Ia flowing in the N-phase circuit of the main circuit 23, it opens and cuts off the main circuit 23 (e.g., the E-phase circuit and the L-phase circuit). This makes it possible to protect the power distribution system 1 from a ground fault (abnormality) occurring in the branch circuit 12 connected to the power receiving outlet 3a.

[0115] In this way, when a ground fault occurs in the branch electric circuit 12 connected to the power receiving outlet 3a, if the ground terminal 4b of the dispersed power source 4 is grounded, the ground fault current Ia flows in the non-grounded wire of the main electric circuit 23 of the power distribution system 1. For this reason, the above-mentioned ground fault can be detected by detecting the ground fault current Ia flowing in the non-grounded wire with the earth leakage breaker 33.

[0116] Note that, like Modification 4, this modification illustrates a case where it is applied to Modification 3, but it can also be applied to the above embodiment or other modifications.

[0117] (Variation 8) In variant example 7, an example is given of a case where a ground fault is detected when the ground terminal 4b of the distributed power source 4 is grounded, whereas in this variant example, an example is given of a case where a ground fault is detected when the ground terminal 4b of the distributed power source 4 is not grounded.

[0118] 9, the power distribution system 1 of this modification further includes a current detection unit 34 in the power distribution system 1 of Modification 7. The current detection unit 34 detects a current flowing in an E-phase electric circuit (ground wire) included in the main electric circuit 23 of the power distribution system 1.

[0119] The earth leakage breaker 33 (protective cut-off unit) of this modification detects an abnormality (e.g., a ground fault) in the branch electric circuit 12 connected to the power receiving outlet 3a (one outlet) based on the detection result of the current detection unit 34, in addition to detecting an abnormality as described in the fifth modification. More specifically, when the detection value of the current detection unit 34 is a current value less than a specified value (i.e., the current detection unit 34 does not detect a ground fault current), the earth leakage breaker 33 is in a closed state to conduct the main electric circuit 23. When the detection value of the current detection unit 34 is a current value equal to or greater than a specified value (i.e., the current detection unit 34 detects a ground fault current), the earth leakage breaker 33 is in an open state to cut off the main electric circuit 23.

[0120] Here, consider a case where the branch electric circuit 12 (e.g., an L-phase electric circuit) connected to the power receiving outlet 3a has a ground fault via a conductive object 200 when the distributed power source 4 is connected. For example, consider a case where the conductive object 200, which is a living thing, comes into contact with the L-phase electric circuit of the branch electric circuit 12, causing a ground fault in the L-phase electric circuit. In this case, as shown in FIG. 9, a ground fault current Ib flows from the L-phase electric circuit of the branch electric circuit 12 to the ground via the conductive object 200. This ground fault current Ib flows from the ground to the E-phase electrode of the power receiving outlet 3a. Then, this ground fault current Ib flows from the E-phase electrode of the power receiving outlet 3a through the second input / output unit 70c of the power distribution system 1 through the E-phase electric circuit of the main electric circuit 23, and flows from the first input / output unit 71c through the electric circuit 16 to the ground terminal 134.

[0121] When the current detection unit 34 detects a ground fault current Ib flowing in the E-phase circuit of the main circuit 23 of the power distribution system 1, the earth leakage breaker 33 opens and interrupts the E-phase circuit and the L-phase circuit of the main circuit 23. This makes it possible to protect the power distribution system 1 from a ground fault (abnormality) occurring in the branch circuit 12 connected to the power receiving outlet 3a.

[0122] In this way, when a ground fault occurs in the branch electric circuit 12 connected to the power receiving outlet 3a, if the ground terminal 4b of the dispersed power source 4 is not grounded, the ground fault current Ib flows through the ground wire of the main electric circuit 23 of the power distribution system 1. For this reason, the above-mentioned ground fault can be detected by detecting the ground fault current Ib flowing through the ground wire with the current detection unit 34.

[0123] (Variation 9) In the seventh and eighth modifications, examples are given of detecting an abnormality occurring in the branch electric circuit 12 connected to the power receiving outlet 3a, but in the seventh modification, as shown in Fig. 10, an example is given of detecting an arc 36 that occurs when the branch electric circuit 12 connected to the power receiving outlet 3a is partially disconnected. Note that a partial disconnection means that one of the two electric circuits is disconnected. The example in Fig. 10 illustrates a case where one of the branch electric circuits 12 (e.g., the L-phase electric circuit) is disconnected and an arc 36 occurs at the disconnected point.

[0124] 10, the power distribution system 1 of this modification includes an arc detection breaker 35 (protective interruption unit) instead of the earth leakage breaker 33 in the power distribution system 1 of the seventh modification. The arc detection breaker 35 detects whether or not the branch electric circuit 12 connected to the power receiving outlet 3a has been partially disconnected and an arc 36 has occurred at the part of the partial disconnection, based on the waveform of the current flowing in the main electric circuit 23 (e.g., an L-phase electric circuit or an N-phase electric circuit) of the power distribution system 1.

[0125] More specifically, when the branch electric circuit 12 is partially broken and an arc 36 occurs at the part of the partial break, the waveform (abnormal waveform) of the current (arc current) flowing through the main electric circuit 23 differs from the waveform (normal waveform) of the current flowing through the main electric circuit 23 when the branch electric circuit 12 is not partially broken. For this reason, the arc detection breaker 35 stores in advance the waveform (abnormal waveform) of the arc current as a reference waveform. Then, when the waveform of the current flowing through the main electric circuit 23 matches the reference waveform (i.e., when the waveform of the current flowing through the main electric circuit 23 is an abnormal waveform), the arc detection breaker 35 detects, based on this match, that the branch electric circuit 12 is partially broken and that an arc 36 has occurred at the part of the break.

[0126] When the waveform of the current flowing in the main electric circuit 23 (e.g., the L-phase electric circuit or the N-phase electric circuit) is normal (i.e., the branch electric circuit 12 is not partially disconnected and an arc 36 is not occurring), the arc detection breaker 35 closes to conduct the main electric circuit 23. When the waveform of the current flowing in the main electric circuit 23 is abnormal (i.e., when an arc 36 occurs), the arc detection breaker 35 opens to shut off the main electric circuit 23. This makes it possible to protect the power distribution system 1 from a partial disconnection of the branch electric circuit 12 connected to the power receiving outlet 3a and an arc occurring at the location of this partial disconnection.

[0127] In this modification, an arc (series arc) that occurs at a partially disconnected portion of the branch electric circuit 12 connected to the power receiving outlet 3a is detected. However, an arc (serial arc) that occurs when a short circuit occurs between two electric circuits (an L-phase electric circuit and an N-phase electric circuit) of the branch electric circuit 12 connected to the power receiving outlet 3a may also be detected.

[0128] In addition, in this modification, the arc detection breaker 35 detects the arc 36 based on the waveform of the current flowing in the main electric circuit 23 , but the arc detection breaker 35 may detect the arc 36 based on the waveform of the voltage generated in the main electric circuit 23 .

[0129] (Variation 10) In the above embodiment, it is assumed that the multiple outlets 3 are all wall outlets provided on the wall of a building. A wall outlet is an outlet that is connected via indoor wiring. The indoor wiring is an electric circuit portion between the branch breaker 133 in the branch electric circuit 12 and the outlets 3. However, the multiple outlets 3 may include a distribution board outlet as an outlet other than a wall outlet. The distribution board outlet is an outlet provided in the distribution board 13, and does not include indoor wiring. In this case, the power distribution system 1 may be built into the distribution board outlet. That is, in this case, the distribution board outlet becomes the power receiving outlet 3a.

[0130] (Other variations) In the above embodiment, the control unit 32 of the power distribution system 1 controls the main breaker 132 from a closed state to an open state to prevent reverse power. However, when the smart meter 14 includes a switch for opening and closing the main electric circuit 11, the control unit 32 may control the switch of the smart meter 14 from a closed state to an open state to prevent reverse power instead of the main breaker 132. In this case, the switch of the smart meter 14 becomes the first switch.

[0131] In the above embodiment, the power distribution system 1 may further include a current detection unit that detects the current input to the second input / output units 70a, 70b (i.e., the output current of the distributed power source 4). In this case, the control unit 32 may determine that the distributed power source 4 is connected to the power receiving outlet 3a when the current detected by the current detection unit exceeds a specified current, and may determine that the distributed power source 4 is not connected to the power receiving outlet 3a when the current detected by the current detection unit does not exceed the specified current.

[0132] (summary) As is apparent from the embodiment and modifications described above, the following aspects are possible.

[0133] The power distribution system (1) of the first embodiment includes a second switch (24). The second switch (24) is provided between the first switch (132) and one of the multiple outlets (3) in an electric circuit (11, 12) that connects the electric power system (2) and the multiple outlets (3) and in which a first switch (132) is provided between the electric power system (2) and the multiple outlets (3). When the first switch (132) is in an open state and power from a distributed power source (4) connected to the one outlet (3a) is supplied to another outlet (3b) other than the one outlet (3a) of the multiple outlets (3), the second switch (24) controls the supply of power from the distributed power source (4) to the other outlet (3b).

[0134] According to this configuration, when power from the distributed power source (4) is input to one outlet (3a) with the first switch (132) in an open state and is supplied to the other outlet (3b), the supply of power from the distributed power source (4) to the other outlet (3b) can be controlled by the second switch (24).

[0135] In the power distribution system (1) of the second embodiment, in the first embodiment, the first switch (132) is in a closed state and the second switch (24) is in an open state.

[0136] According to this configuration, when power is input from the distributed power source (4) to the first outlet (3a) with the first switch (132) in a closed state, the second switch (24) cuts off the input of power from the distributed power source (4). This makes it possible to prevent power supply from the distributed power source (4) and power supply from the power system (2) from occurring simultaneously. In this case, when the first switch (132) is in a closed state (e.g., when there is no power outage), the second switch (24) is in an open state, and therefore the first outlet (3a) cannot be used as a power outlet. Therefore, in this case, the first outlet (3a) becomes an outlet exclusively for the distributed power source.

[0137] The power distribution system (1) of the third aspect includes a connection detection unit (29) that detects whether or not a distributed power source (4) is connected to one of the outlets (3a) in the first aspect. When the first switch (132) is in a closed state and the distributed power source (4) is not connected to the one of the outlets (3a), the second switch (24) is switched from an open state to a closed state.

[0138] According to this configuration, when the first switch (132) is in a closed state and the first outlet (3a) is not connected to the distributed power source (4), the first outlet (3a) can be used as a normal power outlet. Note that a normal power outlet is an outlet that supplies power to an electric device when the electric device is connected to the outlet.

[0139] In the power distribution system (1) of the fourth aspect, in any one of the first to third aspects, the first switch (132) has a function of interrupting the electric circuit (11) when an abnormal current flows through the electric circuit (11).

[0140] According to this configuration, the present invention is applicable when the first switch (132) is a switch with an abnormal current detection function.

[0141] In the power distribution system (1) of the fifth aspect, in any one of the first to fourth aspects, the second switch (24) has a function of interrupting the electric circuit (23) when an abnormal current flows through the electric circuit (23).

[0142] According to this configuration, the second switch (24) controls the power supply from the distributed power source (4) to the other outlet (3b) so that the power supply can be stopped when an abnormal current flows through the electric circuit (23). In other words, the power distribution system (1) can be protected from the abnormal current.

[0143] In the power distribution system (1) of the sixth aspect, in any one of the first to fifth aspects, one outlet (3a) is a three-pole outlet including a ground pole (E phase pole).

[0144] According to this configuration, a distributed power source (4) having a three-pole output section (4a) including a ground electrode can be connected to one outlet (3a).

[0145] In the power distribution system (1) of the seventh aspect, in any one of the first to sixth aspects, the second switch (24) is accommodated in the same housing as one of the outlets (3a).

[0146] According to this configuration, the second switch (24) can be built into one of the outlets (3a).

[0147] The power distribution system (1) of an eighth aspect is any one of the first to seventh aspects, in which the switch is accommodated in the same housing as the second switch (24).

[0148] According to this configuration, the second switch (24) can be built into the first switch (132).

[0149] A power supply system (70) of a ninth aspect includes the power distribution system (1) of any one of the first to eighth aspects and a distributed power source (4).

[0150] According to this configuration, a power supply system (70) including the power distribution system (1) and the distributed power sources (4) can be provided. [Explanation of symbols]

[0151] 1. Power Distribution System 2 Power system 3. Outlets 3a Receiving power outlet (one outlet) 3b Other outlets 4 Distributed power supply 11,23 Main electrical circuit (electrical circuit) 24 Electromagnetic switch (second switch) 29 Second voltage detection unit (connection detection unit) 70 Power System 132 Main breaker (first breaker)

Claims

1. a second switch provided between an electric power system and one of the plurality of outlets in an electric circuit in which a first switch is provided between the electric power system and the plurality of outlets, when the first switch is in an open state and power from a distributed power source connected to the one outlet is supplied to another outlet among the plurality of outlets other than the one outlet, the second switch controls the supply of power from the distributed power source to the other outlet; When the first switch is in a closed state and the distributed power source is not connected to the one outlet, the second switch is controlled to a closed state. Power distribution system.

2. When the first switch is in a closed state, the second switch is in an open state. The electrical power distribution system of claim 1 .

3. An electrical circuit connecting an electric power system and a plurality of outlets, in which a first switch is provided between the electric power system and the plurality of outlets, and a second switch is provided between the first switch and one of the plurality of outlets; a connection detection unit that detects whether a distributed power source is connected to the one outlet, when the first switch is in an open state and when power from the distributed power source connected to the one outlet is being supplied to another outlet among the plurality of outlets other than the one outlet, the second switch controls the supply of power from the distributed power source to the other outlet; When the first switch is in a closed state and the distributed power source is not connected to the one outlet, the second switch is switched from an open state to a closed state. Power distribution system.

4. The first switch has a function of interrupting the electric circuit when an abnormal current flows through the electric circuit. A power distribution system according to any one of claims 1 to 3.

5. The second switch has a function of interrupting the electric circuit when an abnormal current flows through the electric circuit. A power distribution system according to any one of claims 1 to 4.

6. The one outlet is a three-pole outlet including a ground pole. A power distribution system according to any one of claims 1 to 5.

7. The second switch is accommodated in the same housing as the first outlet. A power distribution system according to any one of claims 1 to 6.

8. The first switch is accommodated in the same housing as the second switch. A power distribution system according to any one of claims 1 to 7.

9. A power distribution system according to any one of claims 1 to 8; The distributed power source. Power supply system.

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