Energy management device, energy management system, energy management method and energy management program

Abstract

To provide an energy management device capable of providing a stable supply of electricity across the entire power transmission and distribution network even when a distributed energy resource area is disconnected or grid-connected.SOLUTION: An energy management device includes: a communication unit which performs communications with a trunk energy resource management device that manages a trunk energy resource connected to a power transmission and distribution network and communications with a distributed energy resource management device in each of first and second distributed energy resource areas which have one or a plurality of distributed energy resources, respectively; and a control unit which, when disconnection or grid-connection of the first distributed energy resource area to the power transmission and distribution network is notified, calculates a power demand-supply difference that is a difference between power demand and power supply in the power transmission and distribution network after the disconnection or the grid-connection. The communication unit notifies first information indicating a change of supply power for dissolving the power demand-supply difference to at least one of the trunk energy resource management device and the distributed energy resource management device in the second distributed energy resource area grid-connected to the power transmission and distribution network.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an energy management device, an energy management system, an energy management method, and an energy management program. [Background technology]

[0002] In recent years, a power supply system called a microgrid has been attracting attention (see Patent Document 1, etc.). A microgrid has distributed power sources, including renewable energy power generation, and can be configured to be energy self-sufficient within an area even when disconnected from the power transmission and distribution network. Therefore, it can be a power supply system that is resilient to disasters and other emergencies by efficiently utilizing renewable energy during normal times and operating independently from the power transmission and distribution network in emergencies. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2022-525567 Summary of the Invention [Problem to be solved by the invention]

[0004] Distributed power supply areas with distributed power sources, such as so-called microgrids, are typically interconnected (connected) to a power grid provided by a bulk power source with a power generating device using a synchronous generator, such as an internal combustion engine (thermal power), and the balance of power supply and demand is maintained across the entire power transmission and distribution network. Therefore, if a distributed power supply area is placed in a state similar to that when it is disconnected (isolated) from the power transmission and distribution network due to a power outage or emergency independent operation, it may have a significant impact on the frequency and voltage of the power grid of the power transmission and distribution network. Furthermore, when a distributed power supply area that has been disconnected is reconnected to the grid, it may also have a significant impact on the frequency and voltage of the power grid of the power transmission and distribution network. Such a significant impact on the power grid of the power transmission and distribution network could lead to a power outage or other system accident across the entire power transmission and distribution network.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide an energy management device, an energy management system, an energy management method, and an energy management program that can provide a stable supply of power to the entire transmission and distribution network even when a distributed power source area connected to the transmission and distribution network is disconnected due to a power outage or independent operation, or when it is subsequently reconnected to the grid due to a request for reconnection, etc. [Means for solving the problem]

[0006] The energy management device disclosed herein includes a communication unit that communicates with a core power management unit that manages a core power source connected to a power transmission and distribution network, and with each of the distributed power management units in first and second distributed power source areas, each of which has one or more distributed power sources; and a control unit that, when notified of the disconnection or grid connection of the first distributed power source area to the power transmission and distribution network, derives a power supply and demand difference, which is the difference between the power demand and power supply in the power transmission and distribution network after the disconnection or grid connection, and the communication unit is an energy management device that notifies at least one of the core power management unit and the distributed power management unit in the second distributed power source area connected to the power transmission and distribution network of first information indicating a change in supply power that will eliminate the power supply and demand difference.

[0007] The energy management system of the present disclosure is an energy management system including the above-mentioned energy management device, a distributed power supply management device that manages the distributed power supplies in at least the second distributed power supply area, and a core power supply management device that manages the core power supply.

[0008] The energy management method disclosed herein communicates with a core power management device that manages a core power source connected to a power transmission and distribution network, and with each of the distributed power management devices in first and second distributed power source areas connected to the power transmission and distribution network, and when notified of disconnection or grid connection of the first distributed power source area to the power transmission and distribution network, derives a power supply and demand gap, which is the difference between the demand and supply of power in the power transmission and distribution network after the disconnection or grid connection, and notifies at least one of the core power management device and the distributed power management device in the second distributed power source area of ​​first information indicating a change in supply power that will eliminate the power supply and demand gap.

[0009] The energy management program disclosed herein is an energy management program that causes a computer to execute the following operations: communicating with a core power management device that manages a core power source connected to a power transmission and distribution network; communicating with each of the distributed power management devices in the first and second distributed power source areas connected to the power transmission and distribution network; when notified of disconnection or grid connection of the first distributed power source area to the power transmission and distribution network, deriving a power supply and demand difference that is the difference between the power demand and power supply in the power transmission and distribution network after the disconnection or grid connection; and notifying at least one of the core power management device and the distributed power management device in the second distributed power source area of ​​first information indicating a change in supply power that will eliminate the power supply and demand difference. [Effects of the Invention]

[0010] According to the energy management device, energy management system, energy management method, and energy management program disclosed herein, even if a distributed power source area connected to a power transmission and distribution network is disconnected due to a power outage or independent operation, or if it is subsequently reconnected due to a request for reconnection, a stable supply of power can be provided to the entire power transmission and distribution network. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of an energy management system. [Figure 2] FIG. 2 is a diagram illustrating an example of a hardware configuration of an energy management device. [Figure 3] FIG. 1 is a diagram schematically illustrating a configuration example of a solar power generation device. [Figure 4] FIG. 1 is a diagram schematically illustrating a configuration example of a power storage device. [Figure 5] FIG. 1 is a diagram schematically illustrating an example of the configuration of an emergency generator. [Figure 6] FIG. 10 is a sequence diagram illustrating an example of operation when the first distributed power source area is disconnected. [Figure 7] 10 is a flowchart of an operation plan change process. [Figure 8] 10 is a flowchart showing a change process when there is a supply shortage during parallel-off. [Figure 9] 10 is a flowchart showing a change process when there is an excess supply during parallel-off. [Figure 10] 10 is a flowchart showing a process for changing the number of operating synchronous generators. [Figure 11] FIG. 10 is a sequence diagram illustrating an example of operation when the first distributed power source area is interconnected with the grid. [Figure 12] 10 is a flowchart showing a change process when there is a supply shortage during grid interconnection. [Figure 13] 10 is a flowchart showing a change process when there is an excess supply during grid interconnection. [Figure 14] FIG. 10 is a diagram illustrating a modified example of the energy management system. [Figure 15] FIG. 10 is a diagram illustrating a modified example of the energy management system. DETAILED DESCRIPTION OF THE INVENTION

[0012] An energy management device, an energy management system, an energy management method, and an energy management program according to embodiments of the present disclosure will be described with reference to the drawings. In the description, like elements are designated by like reference numerals, and duplicate descriptions will be omitted as appropriate.

[0013] 1 is a diagram illustrating an example configuration of an energy management system 1 according to an embodiment of the present disclosure. As shown in FIG. 1, the energy management system 1 includes an energy management device 2, a main power source 3, a first distributed power source area 4, a second distributed power source area 5, a power transmission and distribution network 6, and a communication network 7.

[0014] FIG. 2 is a diagram illustrating an example of a hardware configuration of the energy management device 2. As illustrated in this diagram, the energy management device 2 includes a control unit 21 and a communication unit 22. The energy management device 2 may be a so-called information processing device configured mainly with electronic circuits using semiconductor circuit elements. For example, the control unit 21 may include a central processing unit (CPU) 211, a volatile storage unit 212 such as a random access memory (RAM), and a non-volatile storage unit 213 such as a flash memory or a hard disk. The communication unit 22 connects to a communication network 7 to perform communication. The energy management device 2 may be configured with multiple server devices or may have a similar configuration as a virtual server. The information processing performed by the control unit 21 and the communication performed by the communication unit 22 may be realized by the hardware illustrated in FIG. 2 operating in conjunction with programs and data stored in the volatile storage unit 212 and the non-volatile storage unit 213.

[0015] The communication unit 22 of the energy management device 2 can communicate with a core power management device 31 that manages a core power source 3 connected to the power transmission and distribution network 6, and with each of the distributed power management devices in the first distributed power source area 4 and the second distributed power source area 5, each of which has one or more distributed power sources. Furthermore, when the control unit 21 is notified of the disconnection or grid connection of the first distributed power source area 4 to the power transmission and distribution network 6, it can derive a power supply and demand difference, which is the difference between the demand and supply of power in the power transmission and distribution network 6 after the disconnection or grid connection. Furthermore, the communication unit 22 can notify at least one of the core power management device 31 and the second distributed power source area management device 51 in the second distributed power source area 5 connected to the power transmission and distribution network 6 of first information indicating a change in supply power that eliminates the power supply and demand difference. In the following description, the processing of the energy management device 2 can be processing that is performed in conjunction with the control unit 21 and the communication unit 22.

[0016] The first distributed power supply area 4 and the second distributed power supply area 5 may each be a single distributed power supply area, or may include multiple distributed power supply areas. The notification to the bulk power supply 3 and the notification to the second distributed power supply area 5, etc. may be to devices that manage the bulk power supply 3 and the second distributed power supply area 5, etc., respectively, or may be to devices that directly control each distributed power source. Here, the first information may be an updated operation plan. This allows for a stable supply of power to the entire power transmission and distribution network 6, even if a distributed power supply area connected to the grid experiences a power outage or enters isolated operation, or is subsequently re-connected to the grid.

[0017] The bulk power source 3 is composed of power supply devices that supply power to the power transmission and distribution network 6. In the sense that the output power can be adjusted, the bulk power source 3 is primarily assumed to include power generation devices that generate power using synchronous generators 32, such as internal combustion engines (thermal power). However, the synchronous generators 32 may include generators that generate power by rotating turbines using hydroelectric, thermal, nuclear, or other power sources in addition to internal combustion engines. Hydroelectric and nuclear power generation devices may also be included. Furthermore, power generation devices that constitute distributed power sources, as described below, may also be included. In the present disclosure, the bulk power source 3 includes one or more synchronous generators 32, synchronous generator switchgears 33 that control the connection of each synchronous generator 32 to the power transmission and distribution network 6, and a bulk power management device 31. The bulk power management device 31 may control the start and stop of each synchronous generator 32, the increase and decrease of output, the synchronous generator switchgears 33, and the like, via a communication line 34. It may also manage the overall power supplied to the power transmission and distribution network 6 and the operation plans related to the power supplied to the power transmission and distribution network 6. The operation plan may be configured to plan the amount of power generated by each power generation device so that there is neither a surplus nor a deficiency in power supply and demand, based on the power demand forecast, the power generation forecast from renewable energy, the charge state of the power storage device, and the capacity of each power generation device. The operation plan may also be modified as appropriate based on changes in the demand and supply situation. The core power supply management device 31 may control the synchronous generator 32, the synchronous generator switch 33, etc., based on the operation plan. The core power supply management device 31 may be configured as part of a so-called power distribution system. The hardware configuration of the core power supply management device 31 may be the same as that of the energy management device 2 described in FIG. 2, and redundant description will be omitted. The core power source 3 is not limited to this configuration, and may be configured to supply power to the power transmission and distribution network 6.

[0018] The first distributed power source area 4 includes distributed energy resources (DERs). Distributed power sources are typically relatively small-scale power generation devices compared to the power generation devices that make up core power sources, and can include renewable energy power generation devices, fuel-powered power generation devices, and battery (BT) storage devices. Here, renewable energy power generation devices can include power generation devices such as photovoltaic (PV) power generation, wind power generation, small hydroelectric power generation, biomass power generation, and geothermal power generation. Fuel-powered power generation devices can include power generation devices such as diesel engines (DGs), gas engines, and gas turbines. Power storage devices can include household storage batteries, industrial storage batteries, and electric vehicle storage batteries. Furthermore, distributed power sources can include fuel cells and engines that use hydrogen. In the present disclosure, the first distributed power source area 4 has, as distributed power sources, a photovoltaic power generation device ("DER (PV)" in FIG. 1) 42, a power storage device ("DER (BT)" in FIG. 1) 43, and an emergency power generator ("DER (compact DG)" in FIG. 1) 44. However, the distributed power sources may be other distributed power sources instead of these, or may include other distributed power sources in addition to these. Furthermore, there may be one or more of each of the distributed power sources.

[0019] The first distributed power supply area 4 may further include a load 45, a first distributed power supply power line 49, a first distributed power supply area switch 47, and a first distributed power supply area management device 41. The first distributed power supply power line 49 is a power line for supplying power (forward flow) to each of the distributed power sources 42 to 44 and the load 45, or for supplying power (reverse flow) from each of the distributed power sources 42 to 44 to the power transmission and distribution network 6. The first distributed power supply power line 49 can be connected to the power transmission and distribution network 6 via the first distributed power supply area switch 47. The load 45 is a load that consumes power supplied from the distributed power sources 42 to 44 or the power transmission and distribution network 6, and may be a home or a business. The first distributed power supply area management device 41 may communicate with control devices 422, 432, and 442 of the photovoltaic power generation device 42, the power storage device 43, and the emergency power generator 44, respectively, which will be described later, via a communication network 48. This communication makes it possible to acquire the status of each of the photovoltaic power generation device 42, the power storage device 43, and the emergency power generator 44, and to control the operation of each of them. In addition, the first distributed power source area management device 41 may also control a load switch 451 that controls the connection between the load 45 and the first distributed power source power line 49, and a first distributed power source area switch 47.

[0020] The distributed power sources 42-44 and the load 45 in the first distributed power supply area 4 do not need to be located in the same area, as long as they are connectable by a first distributed power supply power line 49. The communication network 48 may be a network using a dedicated line or a public network such as the Internet. The first distributed power supply area management device 41 may be a server device such as a cloud server connected to the Internet as long as it can communicate with the control devices 422, 432, and 442. The core power supply management device 31 may be configured as part of a so-called power distribution system. The hardware configuration of the first distributed power supply area management device 41 may be the same as that of the energy management device 2 described in FIG. 2, and redundant description will be omitted. The first distributed power supply area management device 41 may be configured as a device referred to as a distributed energy resource management system (DERMS).

[0021] By having distributed power sources, the first distributed power source area 4 can be an area having a power system that integrates power supply and power consumption within the area. It can also receive power from the main power source 3. Here, the first distributed power source area 4 may be a microgrid or a regional independent system. However, the first distributed power source area 4 is not limited to this configuration, and may have any configuration as long as it has at least one distributed power source that can be interconnected to the power transmission and distribution network 6 and a control device that is connected to the communication network 7 and controls the distributed power source.

[0022] FIG. 3 is a diagram schematically illustrating an example configuration of a solar power generation system 42. As shown in this diagram, the solar power generation system 42 may include a PV control device 422, a solar power generation panel 423, a PV inverter 424, and a PV switch 421. The solar power generation panel 423 receives light such as sunlight and generates electricity. The PV inverter 424 converts DC power generated by the solar power generation panel 423 into AC power and outputs the AC power. The PV control device 422 controls the output power of the PV inverter 424 and controls the connection between the output power line of the PV inverter 424 and the first distributed power source power line 49 via the PV switch 421. The PV control device 422 communicates with the first distributed power source area management device 41 via a communication network 48. Through this communication, the PV control device 422 can notify the first distributed power source area management device 41 of the power generation status of the solar power generation panel 423. Furthermore, through this communication, the PV control device 422 may control the output of the PV inverter 424 and control the connection between the PV inverter 424 and the first distributed power source power line 49 by the PV switch 421, based on instructions from the first distributed power source area management device 41. Note that the first distributed power source area management device 41 may issue instructions directly to the PV inverter 424, or may issue instructions via an information processing device other than the PV control device 422. Note that the hardware configuration of the PV control device 422 may be the same as that of the energy management device 2 described in FIG. 2, and redundant description will be omitted.

[0023] FIG. 4 is a diagram schematically illustrating an example configuration of the power storage device 43. As shown in this diagram, the power storage device 43 may include a BT control device 432, a storage battery 433, a BT inverter 434, and a BT switch 431. The storage battery 433 can be in any one of the following states: charging (storing supplied power), discharging (supplying power), or neither charging nor discharging. The BT inverter 434 can convert DC power discharged by the storage battery 433 into AC power and output the converted AC power. The BT inverter 434 can also convert AC power into DC power to charge the storage battery 433. The BT control device 432 may control the output power of the BT inverter 434 and the BT switch 431 to control the connection between the input / output power line of the BT inverter 434 and the first distributed power source power line 49, thereby controlling switching between charging and discharging the storage battery 433. The BT control device 432 communicates with the first distributed power source area management device 41 via a communication network 48. Through this communication, the BT control device 432 can notify the first distributed power source area management device 41 of the state of charge (SOC) of the storage battery 433. Furthermore, through this communication, the BT control device 432 may control the input / output of the BT inverter 434, switch the charge / discharge state, and control the connection between the BT inverter 434 and the first distributed power source power line 49 by the BT switch 431, based on instructions from the first distributed power source area management device 41. Note that the first distributed power source area management device 41 may issue instructions directly to the BT inverter 434, or may issue instructions via an information processing device other than the BT control device 432. Note that the hardware configuration of the BT control device 432 can be the same as that of the energy management device 2 described in FIG. 2, and therefore a duplicated description will be omitted.

[0024] FIG. 5 is a diagram schematically illustrating an example configuration of the emergency generator 44. As shown in this diagram, the emergency generator 44 may include a DG control device 442, a small diesel generator 443, a DG power conversion unit 444, and a DG switch 441. The small diesel generator 443 may be an emergency generator that generates power using an internal combustion engine that uses diesel fuel, for example. The DG power conversion unit 444 converts the AC power generated by the small diesel generator 443 into AC power that can be supplied to the first distributed power source power line 49 and outputs the converted power. The DG control device 442 controls the output power of the DG power conversion unit 444 and controls the connection between the output power line of the DG power conversion unit 444 and the first distributed power source power line 49 using the DG switch 441. The DG control device 442 may also control the amount of power generated by the small diesel generator 443. The DG control device 442 communicates with the first distributed power source area management device 41 via a communication network 48. Through this communication, the DG control device 442 can notify the first distributed power source area management device 41 of the power generation status of the small diesel generator 443. Furthermore, through this communication, the DG control device 442 may control the power generation of the small diesel generator 443, control the output of the DG power conversion unit 444, and control the connection between the DG power conversion unit 444 and the first distributed power source power line 49 by the DG switch 441, based on instructions from the first distributed power source area management device 41. Note that the first distributed power source area management device 41 may issue instructions to the DG power conversion unit 444 directly, or may issue instructions via an information processing device other than the DG control device 442. Note that the hardware configuration of the DG control device 442 may be the same as that of the energy management device 2 described in FIG. 2, and therefore a redundant description will be omitted.

[0025] The second distributed power supply area 5, like the first distributed power supply area 4, may have a photovoltaic power generation device ("DER (PV)" in FIG. 1) 52, a power storage device ("DER (BT)" in FIG. 1) 53, and an emergency power generator ("DER (compact DG)" in FIG. 1) 54. The second distributed power supply area 5 may also have a load 55, a second distributed power supply power line 59, a second distributed power supply area switch 57, and a second distributed power supply area management device 51, like the first distributed power supply area 4. The configuration of the second distributed power supply area 5 is the same as that of the first distributed power supply area 4 described using FIG. 1 and FIGS. 2 to 5, and therefore a duplicated description will be omitted.

[0026] 6 is a sequence diagram illustrating an operation example S100 when the first distributed power supply area 4 is disconnected in the energy management system 1 according to the present disclosure. As shown in this diagram, first, in step S101, the bulk power supply 3, the first distributed power supply area 4, and the second distributed power supply area 5 in the energy management system 1 are each connected to the power transmission and distribution network 6 and are operating based on an initial operation plan. Subsequently, the energy management device 2 receives a notification from the first distributed power supply area management device 41 that the first distributed power supply area 4 will be disconnected (decoupled) from the power transmission and distribution network 6 (step S102). Here, the disconnection of the first distributed power supply area 4 includes disconnection from the power transmission and distribution network 6 due to the independent operation of the first distributed power supply area 4 and disconnection due to a power outage of the first distributed power supply area 4, but may also be disconnection due to other causes. If the power outage is due to the first distributed power supply area 4, there may be no notification of parallel-off as in step S102. In that case, the energy management device 2 may directly or indirectly detect that the first distributed power supply area 4 has been parallel-off, or may receive a notification of the detection. The notification of parallel-off may include such detection or notification of the detection. When the notification of parallel-off is received, the operation plan change process S200 is executed.

[0027] FIG. 7 is a flowchart of the operation plan change process S200 in the energy management device 2. In the operation plan change process S200, first, it is determined whether the request is for parallel-off of the distributed power source area or for grid connection. In the above example, since the first distributed power source area 4 has notified the user of parallel-off, the case of a parallel-off request will be described. In the case of a parallel-off request, the process proceeds to step S202, where the difference between power supply and demand in the power transmission and distribution network 6 after parallel-off is calculated as the power supply and demand difference to determine whether there is a power supply and demand difference. If there is a power supply and demand difference, it is determined whether there is a power shortage or an excess. Here, if the first distributed power source area 4 has supplied power to the power transmission and distribution network 6, there is a power supply shortage. Conversely, if the first distributed power source area 4 has received power from the power transmission and distribution network 6, there is an excess power supply. Note that if it is known that the power supply and demand states of the bulk power source 3 and the second distributed power source area 5 differ in the prior operation plan, the calculation may take into account the change in the power supply and demand state.

[0028] In cases such as when the first distributed power source area 4 is neither supplying nor receiving power to the power transmission and distribution network 6, the supply and demand match, so there is no power supply and demand difference (step S202: supply and demand match), and there is no change to the operation plan (step S203), so the operation plan change process S200 ends. Here, when there is no power supply and demand difference, a predetermined range (error) may be included. For example, the predetermined range may be 1 to several percent of the total power supplied to the power transmission and distribution network 6. If the power supply and demand difference is determined to result in a power supply shortage (step S202: supply shortage), the change process S400 for supply shortage at time of parallel-off is started. On the other hand, if the power supply and demand difference is determined to result in a power supply excess (step S202: supply excess), the change process S500 for supply excess at time of parallel-off is started.

[0029] 8 is a flowchart showing the change process S400 in the energy management device 2 when there is a supply shortage during parallel-off. As shown in this flowchart, first, in step S401, the energy management device 2 sets a change to increase the output of the synchronous generator 32 in operation, and in step S402, determines whether the increase in the output of the synchronous generator 32 in operation is sufficient. If it is determined that the increase is sufficient (step S402: Yes), the change process S400 when there is a supply shortage during parallel-off ends. On the other hand, if it is not determined that the increase is sufficient (step S402: No), the process proceeds to step S403.

[0030] In step S403, a change to increase the output of the power storage device 43 is set, and in step S404, it is determined whether the increase in the output increase settings of the synchronous generator 32 and the power storage device 43 is sufficient. If it is determined that the increase is sufficient (step S404: Yes), the change process for supply shortage at parallel-off S400 is terminated. On the other hand, if it is not determined that the increase is sufficient (step S404: No), the process proceeds to step S405.

[0031] In step S405, a change is set to increase the output of the emergency generator 54 in the second distributed power source area 5, and in step S406, it is determined whether the increase in the output of the synchronous generator 32, the power storage device 43, and the emergency generator 54 is sufficient. If it is determined that the increase is sufficient (step S406: Yes), the change process for supply shortage at parallel-off S400 is terminated. On the other hand, if it is not determined that the increase is sufficient (step S406: No), the process proceeds to step S407. In step S407, a setting is made to later execute the process for changing the number of operating synchronous generators S300, which will be described later. This setting can be, for example, setting a flag for executing the process for changing the number of operating synchronous generators S300, which will be described later. Note that the increase in the output of the emergency generator 54 may include starting operation of the emergency generator 54.

[0032] This change process S400 in the event of a supply shortage during parallel-off can be applied by omitting the process for the distributed power sources that do not include either the power storage device 53 or the emergency generator 54, even if the distributed power source area 4 does not include either the power storage device 53 or the emergency generator 54. When the first distributed power source area 4 is parallel-off and the difference between power supply and demand indicates a supply shortage, the control unit 21 may include a command to allocate the required output increase amount to the operating synchronous generators 32 in the main power source 3, the power storage device 43, and the emergency generator 44, in that order. In this case, the allocated output increase amount can be equal to or less than the upper limit output of each. Note that it is not necessary to set an increase in the number of operating synchronous generators 32.

[0033] Here, the operating synchronous generator 32, the power storage device 53, and the emergency generator 54 in the main power source 3 are power supply devices that can quickly increase output power. Therefore, even if the first distributed power source area 4 in the power transmission and distribution network 6 is suddenly disconnected, the balance between power supply and demand can be quickly and efficiently improved.

[0034] 9 is a flowchart showing the change process S500 in the energy management device 2 when there is an excess supply during parallel-off. As shown in this flowchart, first, in step S501, the energy management device 2 sets a change to reduce the output of the synchronous generator 32 in operation, and in step S502, determines whether the output reduction setting of the synchronous generator 32 in operation is sufficient. If it is determined that the reduction amount is sufficient (step S502: Yes), the change process S500 in the event of an excess supply during parallel-off is terminated. On the other hand, if it is not determined that the reduction amount is sufficient (step S502: No), the process proceeds to step S503.

[0035] In step S503, a change to reduce the output of the power storage device 53 is set, and in step S504, it is determined whether the amount of reduction is sufficient with the output reduction settings of the synchronous generator 32 and the power storage device 53. If it is determined that the amount of reduction is sufficient (step S504: Yes), the change processing S500 for excessive supply during parallel-off is terminated. On the other hand, if it is not determined that the amount of reduction is sufficient (step S504: No), the process proceeds to step S505.

[0036] In step S505, a change to reduce the output of the photovoltaic power generation device 52 is set, and in step S506, it is determined whether the output reduction settings of the synchronous generator 32, the power storage device 53, and the photovoltaic power generation device 52 result in a sufficient reduction amount. If it is determined that the reduction amount is sufficient (step S506: Yes), the change process S500 for excessive supply at parallel-off is terminated. On the other hand, if it is not determined that the reduction amount is sufficient (step S506: No), the process proceeds to step S507. In step S507, a setting is made to later execute the process S300 to change the number of operating synchronous generators, which will be described later. This setting can be, for example, setting a flag for executing the process S300 to change the number of operating synchronous generators, which will be described later.

[0037] The change process S500 for excessive supply during parallel-off can be applied by omitting the process for the distributed power sources that do not include either the power storage device 53 or the photovoltaic power generation device 52, even if the distributed power source area 4 does not include either the power storage device 53 or the photovoltaic power generation device 52. When the first distributed power source area 4 is parallel-off and the difference between power supply and demand indicates an excess supply, the control unit 21 may include the first information allocating the required output reduction amount to the operating synchronous generators 32 in the main power source 3, the power storage device 53, and the photovoltaic power generation device 52, in that order. In this case, the allocated output reduction amount can be equal to or greater than the lower limit output for the synchronous generators 32 and equal to or less than the upper limit charge amount per hour for the power storage device 53. Note that it is not necessary to set a reduction in the number of operating synchronous generators 32.

[0038] Here, the lower limit output of the synchronous generator 32 can be set to a lower limit output (for example, 50% of the maximum output) within a range that does not cause the operating synchronous generator 32 to stop. In the case of the power storage device 53, the meanings of "output reduction," "output reduction," and "output reduction amount" include not only reduction of discharge output, but also switching from discharge to charge and increasing the charge amount. The operating synchronous generator 32 and the solar power generation device 52 in the main power source 3 are power supply devices that can quickly reduce their output power, and the power storage device 53 can input and store power by switching to a charge mode. Therefore, even if the first distributed power source area 4 is suddenly disconnected in the power transmission and distribution network 6, the balance between power supply and demand can be quickly and efficiently improved.

[0039] Returning to the operation example S100 when the first distributed power supply area 4 is disconnected in FIG. 6 , when the operation plan change process S200 is completed, it is determined in step S104 whether or not there has been a change to the operation plan. Here, if it is determined that supply and demand do not match in the calculation of the difference between power supply and demand after disconnection in the operation plan change process S200 (step S202), a change to the operation plan will occur. If it is determined that there has been no change to the operation plan, the process ends (step S104: No). If it is determined that there has been a change to the operation plan, the energy management device 2 can transmit first information indicating the change to the operation plan to the core power management device 31 and the second distributed power supply area management device 51 in step S105.

[0040] In step S111, the core power source management device 31 that has received the first information can start operation of the synchronous generator 32 based on the content of the first information. In step S113, the second distributed power source area management device 51 that has received the first information can start operation of the distributed power sources 52 to 54 based on the content of the first information. If the parallel-off notification in step S102 indicates that the first distributed power source area 4 is in a controllable state, such as by starting independent operation, the first information in step S105 can also be sent to the first distributed power source area management device 41. In this case, the timing of the start of independent operation in the first distributed power source area 4 (step S112) can be synchronized with the timing of the start of operation of the core power source 3 and the second distributed power source area 5 based on the content of the first information. Synchronizing the timing shortens the period during which there is a risk of a gap in power supply and demand, enabling a more stable power supply to the entire power transmission and distribution network 6.

[0041] Subsequently, in step S115, the energy management device 2 determines whether a request to change the number of operating synchronous generators 32 (setting in the operation plan change process S300) has been made in the operation plan change process S200, or whether an abnormality in the state of charge (SOC) of the power storage device 53 has been notified. Here, in step S115, it may be additionally determined whether operation based on the first information has continued for a long period of time. Here, a long period of time may be defined as, for example, 30 minutes or 60 minutes. The notification of an abnormality in the state of charge (SOC) is not limited to an abnormality notification. Alternatively, it may be determined that an abnormality has been notified when the notified state of charge (SOC) is a fully charged state close to 100% (e.g., 90%) during charging, or an empty state close to 0% (e.g., 10%) during discharging. If it is not determined that a request to change the number of operating synchronous generators 32 has been made or an abnormality in the state of charge (SOC) of the power storage device 53 has been notified (step S115: No), the process of step S115 may be repeated. If it is determined that there has been a request to change the number of operating synchronous generators 32, or that an abnormality in the state of charge (SOC) of the storage device 53 has been notified (step S115: Yes), the process proceeds to the number of operating synchronous generators change process S300.

[0042] FIG. 10 is a flowchart showing the process S300 for changing the number of operating synchronous generators in the energy management device 2. As shown in this flowchart, first, in step S301, the energy management device 2 acquires the state of charge (SOC) of the power storage device 53. Note that if information on the power storage device 53 to be considered and the state of charge (SOC) is already available, the process of step S301 may be omitted. Subsequently, in step S302, an increase or decrease in the number of operating synchronous generators 32 is determined taking into consideration the current power supply and demand situation in the power transmission and distribution network 6 and the like and the state of charge (SOC) of the power storage device 53. In step S303, an operation plan after changing the number of operating synchronous generators 32 is created as the content of the second information, and the process ends. Here, the operation plan after changing the number of operating synchronous generators 32 may include outputs for charging / discharging the power storage devices 53 that are discharged / charged based on the first information. Furthermore, the control unit 21 can create an operation plan that instructs each distributed power supply device in the second distributed power supply area 5 to operate according to the operation plan that was in effect before the notification of the first information, when the main power supply 3 implements the content of the second information. As a result, for example, if the operation based on the first information was an emergency response, the operation based on the second information can be a continuous response that involves returning to the previous operation plan. As a result, the operation based on the first information can be an operation that can respond quickly to sudden parallel-off of the first distributed power supply area 4, etc. Furthermore, even if the operation based on the first information cannot be a continuous response, for example, the operation based on the second information can be a continuous response, including changing the number of operating synchronous generators 32, which requires a preparation period.

[0043] Returning to the operation example S100 when the first distributed power supply area 4 is paralleled off in FIG. 6 , when the process S300 for changing the number of operating synchronous generators is completed, the energy management device 2 can transmit second information, which is an instruction to change the operation plan, to the core power supply management device 31 and the second distributed power supply area management device 51 in step S121. Having received the second information, the core power supply management device 31 can prepare to start or stop the operation of the synchronous generator 32 based on the content of the second information in step S122. Furthermore, in step S123, the core power supply management device 31 can start or stop the operation of the synchronous generator 32 at the instructed timing. Furthermore, in step S124, the second distributed power supply area management device 51 can start the operation of the distributed power sources 52 to 54 based on the content of the second information at the instructed timing for starting or stopping the operation of the synchronous generator 32. By synchronizing the timing, the period in which there is a risk of a difference in power supply and demand is reduced, thereby enabling a more stable power supply to the entire power transmission and distribution network 6.

[0044] In this way, when the first information regarding a power supply shortage includes allocating increased output to the storage device 43 or the emergency generator 44, the control unit 21 can notify the main power source 3 of second information that further includes increasing the number of operating synchronous generators 32.

[0045] Here, the second information may be notified when the difference between power supply and demand indicates a supply shortage even during operation based on the first information. The second information may be notified when operation based on the first information continues for a predetermined time or more, such as 30 minutes or more, or when the state of charge (SOC) of the power storage device 43 that is to be discharged based on the first information is determined to be in an empty state. Here, the second information may be provided by updating the operation plan. As a result, even if the response based on the first information in the power transmission and distribution network 6 is an emergency response, the operation based on the second information can efficiently improve the balance of power supply and demand as a more continuous response.

[0046] Furthermore, the output of the synchronous generator 32 based on the second information for the main power source 3 can include an output increase for charging the power storage device 43 that is discharging based on the first information. As a result, for example, the power storage device 43 that was undergoing emergency discharging based on the first information can be returned to a normal charging state by applying the contents of the second information.

[0047] Furthermore, when the first information regarding an excess power supply includes an allocation of output reduction to the power storage device 43 or the solar power generation device 42, the control unit 21 can notify the main power source 3 of second information for further reducing the number of operating synchronous generators 32.

[0048] Here, the second information can be notified when the difference between power supply and demand indicates an oversupply even during operation based on the first information. Furthermore, the second information can be notified when operation based on the first information continues for a predetermined time or more, such as 30 minutes or more, or when the state of charge (SOC) of the power storage device 43 that is to be charged based on the first information is determined to be fully charged. Here, the second information can be an updated operation plan. This allows the second instruction to be a more continuous response in the power transmission and distribution network 6, thereby efficiently improving the balance between power supply and demand.

[0049] Furthermore, the output of the synchronous generator 32 based on the second information for the main power source 3 can include an output reduction that takes into account the discharge of the power storage device 43 that is charged based on the first information. As a result, for example, the power storage device 43 that was being charged temporarily based on the first information can be returned to a normal charging state by applying the second information.

[0050] 11 is a sequence diagram illustrating an operation example S800 when the first distributed power supply area 4 is connected to the grid in the energy management system 1 according to the present disclosure. As shown in this diagram, first, in step S801, the first distributed power supply area 4 in the energy management system 1 is disconnected from the power transmission and distribution network 6 and is operating independently. Subsequently, the energy management device 2 (controller 21 thereof) receives a notification of a grid connection request for connecting the first distributed power supply area 4 to the power transmission and distribution network 6 from the first distributed power supply area management device 41 (step S802). Here, grid connection of the first distributed power supply area 4 includes reconnection to the power transmission and distribution network 6 from a state in which it has been disconnected due to parallel-off. The grid connection may be caused by the following reasons: the state of charge (SOC) of the power storage device 43 in the first distributed power source area 4, which has been operating independently, is fully charged and close to 100% (e.g., 90%); the state of charge (SOC) of the power storage device 43 is fully charged and close to 0% (e.g., 10%); the state of charge (SOC) of the power storage device 43 in the first distributed power source area 4 is fully discharged and close to 0% (e.g., 10%); or the first distributed power source area 4 has been restored from a power outage; or other reasons may be involved. Upon receiving the notification of grid connection, in steps S803 and S804, the state of charge (SOC) of the power storage device 43 in the first distributed power source area 4 and the state of charge (SOC) of the power storage device 53 in the second distributed power source area 5 after grid connection is received. If information on the state of charge (SOC) of the power storage device 43 or 53 to be considered is already available, steps S803 and S804 may be omitted, or either one of steps S803 and S804 may be performed. Subsequently, the operation plan change process S200 is performed.

[0051] Returning to FIG. 7 , the case of a grid interconnection request in the operation plan change process S200 will be described. As shown in this sequence diagram, in step S201, it is determined whether the request is for parallel-off of the distributed power source area or for grid interconnection, and it is determined that the request is for grid interconnection (step S201: grid interconnection request). In this case, the process proceeds to step S205, where the difference between power supply and demand in the power transmission and distribution network 6 after parallel-off is calculated as the power supply and demand difference, and it is determined whether there is a power supply and demand difference. In this calculation, when the power storage device 43 in the first distributed power source area 4 is in a fully charged state, the power storage device 43 may be calculated as discharging, and when the power storage device 43 is in an empty charge state, the power storage device 43 may be calculated as charging. Furthermore, when the power storage device 53 in the second distributed power source area 5 is in a fully charged state, the power storage device 53 may be calculated as discharging, and when the power storage device 53 is in an empty charge state, the power storage device 53 may be calculated as charging. As a result, in the change process S600 or S700 described below, even if the charge state of the storage device 43 or 53 is in a fully charged state or an empty charged state in a disconnected state such as standalone operation or a power outage, the state can be canceled after grid connection.

[0052] If there is no difference between power supply and demand (step S205: supply and demand match), there is no change to the operation plan (step S206), and the operation plan change process S200 ends. The predetermined range in which there is no difference between power supply and demand is the same as in the case of parallel-off, so a duplicated explanation will be omitted. If the power supply and demand difference is determined to result in a power supply shortage (step S205: supply shortage), the change process S600 for when there is a supply shortage during grid connection is started. On the other hand, if the power supply and demand difference is determined to result in an excess power supply (step S205: supply shortage), the change process S700 for when there is an excess power supply during grid connection is started.

[0053] 12 is a flowchart showing the change processing S600 in the energy management device 2 when there is a shortage of supply during grid connection. As shown in this flowchart, first, in step S601, the energy management device 2 sets a change to increase the output of the synchronous generator 32 in operation, and in step S602, determines whether the increase in the output increase setting of the synchronous generator 32 in operation is sufficient. If it is determined that the increase is sufficient (step S602: Yes), the change processing S600 when there is a shortage of supply during grid connection is terminated. On the other hand, if it is not determined that the increase is sufficient (step S602: No), the process proceeds to step S603.

[0054] In step S603, a change to increase the output of the power storage device 43 is set, and in step S604, it is determined whether the increase in the output increase settings of the synchronous generator 32 and the power storage device 43 is sufficient. If it is determined that the increase is sufficient (step S604: Yes), the change processing S600 for when there is a supply shortage during grid connection is terminated. On the other hand, if it is not determined that the increase is sufficient (step S604: No), the process proceeds to step S605.

[0055] In step S605, a change is set to increase the output of the emergency generator 54 in the second distributed power source area 5, and in step S606, it is determined whether the increase in the output of the synchronous generator 32, the power storage device 43, and the emergency generator 54 is sufficient. If it is determined that the increase is sufficient (step S606: Yes), the change process S600 for when there is a supply shortage during grid connection is terminated. On the other hand, if it is not determined that the increase is sufficient (step S606: No), the process proceeds to step S607. In step S607, it is set to increase the number of operating synchronous generators 32. Note that the increase in the output of the emergency generator 54 may include starting operation of the emergency generator 54.

[0056] The change process S600 for grid-connected supply shortage can be applied even when either the power storage device 53 or the emergency generator 54 is not included, or when neither is included, by omitting the process for the distributed power source that does not include the power storage device 53 or the emergency generator 54. The power supply-demand difference may be calculated by assuming that the power storage device 43 is discharging when the power storage device 43 in the grid-connected first distributed power source area 4 is fully charged, and by assuming that the power storage device 43 is charging when the power storage device 43 is empty. Furthermore, when the power supply-demand difference indicates a supply shortage, the control unit 21 may use the first information as the required output increase amount to allocate the required output to the operating synchronous generators 32, the power storage device 43, and the emergency generator 44 in that order, at or below their respective upper limit outputs. Note that the setting for increasing the number of operating synchronous generators 32 may not be required.

[0057] Here, the operating synchronous generators 32, the power storage devices 53, and the emergency generators 54 in the main power source 3 are power supply devices that can increase their output power quickly. Therefore, the balance between power supply and demand can be improved quickly and efficiently. Furthermore, when the allocation does not achieve the required output increase amount, the control unit 21 may include the first information further including an increase in the number of operating synchronous generators 32. This allows the balance between power supply and demand to be improved efficiently. Here, when calculating the difference between power supply and demand, if the power storage device 53 in the second distributed power source area 5 is fully charged, the calculation may be performed assuming that the power storage device 53 is discharging, and if the charge state of the power storage device 53 is insufficient, the calculation may be performed assuming that the power storage device 53 is charging.

[0058] 13 is a flowchart showing the change processing S700 in the energy management device 2 when there is an excess supply during grid connection. As shown in this flowchart, first, in step S701, the energy management device 2 sets a change to reduce the output of the synchronous generator 32 in operation, and in step S702, determines whether the output reduction setting of the synchronous generator 32 in operation is sufficient. If it is determined that the reduction amount is sufficient (step S702: Yes), the change processing S700 in the event of an excess supply during grid connection is terminated. On the other hand, if it is not determined that the reduction amount is sufficient (step S702: No), the process proceeds to step S703.

[0059] In step S703, a change to reduce the output of the power storage device 53 is set, and in step S704, it is determined whether the amount of reduction is sufficient with the output reduction settings of the synchronous generator 32 and the power storage device 53. If it is determined that the amount of reduction is sufficient (step S704: Yes), the change processing S700 for when there is an excess supply during grid connection is terminated. On the other hand, if it is not determined that the amount of reduction is sufficient (step S704: No), the process proceeds to step S705.

[0060] In step S705, a change to reduce the output of the photovoltaic power generation device 52 is set, and in step S706, it is determined whether the output reduction settings of the synchronous generator 32, the power storage device 53, and the photovoltaic power generation device 52 result in a sufficient reduction amount. If it is determined that the reduction amount is sufficient (step S706: Yes), the change processing S700 for grid-connected oversupply is terminated. On the other hand, if it is not determined that the reduction amount is sufficient (step S706: No), the process proceeds to step S707. In step S707, a reduction in the number of operating synchronous generators 32 is set.

[0061] The change process S700 for grid-connected oversupply can be applied even when either the power storage device 53 or the photovoltaic power generation device 52 is not included, or when neither is included, by omitting the process for the distributed power source that does not include the power storage device 53 or the photovoltaic power generation device 52. The power supply-demand difference may be calculated by assuming that the power storage device 43 is discharging when the power storage device 43 in the grid-connected first distributed power source area 4 is fully charged, and by assuming that the power storage device 43 is charging when the power storage device 43 is empty. When the power supply-demand difference is oversupply, the control unit 21 may use first information that allocates the required output reduction amount to the synchronous generator 32, the power storage device 43, and the photovoltaic power generation device 42 in operation in this order. The synchronous generator 32 may be allocated a lower limit output or more, and the power storage device 43 may be allocated an upper limit charge amount per hour or less. Note that the setting for reducing the number of operating synchronous generators 32 may not be required.

[0062] Here, the lower limit output of the synchronous generator 32 can be set to a lower limit output (for example, 50% of the maximum output) within a range that does not cause the synchronous generator 32 in operation to stop. In the case of the power storage device 43, the meanings of "output reduction," "output reduction," and "output reduction amount" include not only reduction of discharge output, but also switching from discharge to charge and increasing the charge amount. The synchronous generator 32 and the solar power generation device 42 in operation in the main power source 3 are power supply devices that can quickly reduce their output power, and the power storage device 43 can input and store power by switching to a charge mode. This makes it possible to quickly and efficiently improve the balance between power supply and demand.

[0063] When the allocation does not achieve the required output reduction amount, the control unit 21 can include in the first information a further reduction in the number of operating synchronous generators 32. This makes it possible to efficiently improve the balance between power supply and demand.

[0064] When the first information includes a change in the number of operating synchronous generators 32, the control unit 21 can connect the first distributed power supply area 4 to the grid at the timing when the number of operating synchronous generators 32 changes. The instruction to connect the first distributed power supply area 4 to the grid can be sent to a device that manages the first distributed power supply area switch 47 for connecting the first distributed power supply area 4 to the grid. The instruction to connect the first distributed power supply area 4 to the grid can be sent by directly notifying the first distributed power supply area switch 47 of the opening and closing timing, or by a management device for the first distributed power supply area 4 or the bulk power supply 3 that manages the first distributed power supply area switch 47. Here, the instruction to connect the first distributed power supply area 4 to the grid can be sent by updating the operation plan. When a change in the number of operating synchronous generators 32 is included, it may take time to start or stop the synchronous generators 32. Therefore, by connecting the first distributed power source area 4 to the grid at a time when the difference between power supply and demand can be eliminated, the first distributed power source area 4 can be connected to the grid more safely to the power transmission and distribution network 6.

[0065] As described above, the energy management device 2 can determine the amount of increase or decrease in output of the operating synchronous generator 32 in order to eliminate the difference between power supply and demand after the first distributed power source area 4 is disconnected or connected to the grid, as shown in Figures 8, 9, 12, and 13.

[0066] 8, 9, 12, and 13, the energy management device 2 can determine the amount of output increase or reduction of the power storage device 53 after determining the amount of output increase or reduction of the synchronous generator 32. Here, the amount of output reduction of the power storage device 53 can include the amount of output reduction due to an increase in the charge amount. Furthermore, after determining the amount of output increase or reduction of the synchronous generator 32 that is in operation, the amount of output increase or reduction of the power storage device 53 may be determined before or after the amount of output increase or reduction of the power storage device 53.

[0067] 8 and 12, the energy management device 2 can determine the amount of output increase or reduction of the emergency generator 54 after determining the amount of output increase or reduction of the synchronous generator 32. Furthermore, after determining the amount of output increase or reduction of the synchronous generator 32 that is in operation, the amount of output increase or reduction of another power supply device (or power consuming device) may be determined before determining the amount of output increase or reduction of the emergency generator 54.

[0068] 9 and 13, the energy management device 2 can determine the output reduction amount of the photovoltaic power generation device 52 after determining the output increase amount or output reduction amount of the synchronous generator 32. Furthermore, after determining the output increase amount or output reduction amount of the synchronous generator 32 that is in operation, the output increase amount or output reduction amount of another power supply device (or power consuming device) may be determined before determining the output reduction amount of the photovoltaic power generation device 52.

[0069] 8, 9, 12, and 13, the energy management device 2 can determine an increase or decrease in the number of operating synchronous generators 32 after determining the amount of output increase or decrease of the synchronous generators 32. Furthermore, after determining the amount of output increase or decrease of the synchronous generators 32 currently in operation, the energy management device 2 may determine the amount of output increase or decrease of another power supply device (or power consuming device) between the determination of the increase or decrease in the number of operating synchronous generators 32.

[0070] 8, 9, 12, and 13, the energy management device 2 can determine the amount of output increase or reduction of the power storage device 53 in order to eliminate the difference between power supply and demand after the first distributed power source area 4 is disconnected or connected to the grid. Here, the amount of output reduction of the power storage device 53 can include the amount of output reduction due to an increase in the amount of charge.

[0071] 8 and 12, the energy management device 2 can determine the output increase amount of the emergency generator 54 after determining the output increase amount or output reduction amount of the power storage device 53. Furthermore, after determining the output increase amount or output reduction amount of the power storage device 53, the output increase amount or output reduction amount of another power supply device (or power consuming device) may be determined before determining the output increase amount of the emergency generator 54.

[0072] 9 and 13, the energy management device 2 can determine the output reduction amount of the solar power generation device 52 after determining the output increase amount or output reduction amount of the power storage device 53. Furthermore, after determining the output increase amount or output reduction amount of the power storage device 53, the output increase amount or output reduction amount of another power supply device (or power consuming device) may be determined before determining the output reduction amount of the solar power generation device 52.

[0073] 8, 9, 12, and 13, the energy management device 2 can determine an increase or decrease in the number of operating synchronous generators 32 after determining the amount of output increase or decrease of the power storage device 53. Furthermore, after determining the amount of output increase or decrease of the power storage device 53, the amount of output increase or decrease of the power storage device 53 may be determined before or after determining the amount of output increase or decrease of the power storage device 53.

[0074] 8 and 12, the energy management device 2 can determine the amount of increase in output of the emergency generator 54 in order to eliminate the difference between power supply and demand after parallel-off or grid connection in the first distributed power source area 4. After determining the amount of increase in output of the emergency generator 54, the energy management device 2 can decide to increase or reduce the number of operating synchronous generators 32. After determining the amount of increase in output of the emergency generator 54, the amount of increase or reduction in output of another power supply device (or power consuming device) may be determined between the decision to increase or reduce the number of operating synchronous generators 32.

[0075] 9 and 13, the energy management device 2 can determine the amount of output reduction of the photovoltaic power generation device 52 in order to eliminate the difference between power supply and demand after the first distributed power source area 4 is disconnected or connected to the grid. After determining the amount of output reduction of the photovoltaic power generation device 52, the energy management device 2 can determine an increase or decrease in the number of operating synchronous generators 32. After determining the amount of output reduction of the photovoltaic power generation device 52, the amount of output increase or decrease of another power supply device (or power consuming device) may be determined between the determination of the increase or decrease in the number of operating synchronous generators 32.

[0076] In the above disclosure, one distributed power supply area management device is provided in each distributed power supply area, but the configuration of the energy management system 1 is not limited to this. For example, as shown in the energy management system 1 of FIG. 14 , a distributed power supply area management device 41A can communicate with one or more second distributed power supply areas 5 as well as a first distributed power supply area 4 where parallel-off and grid connection are performed. In this case, the distributed power supply area management device 41A may control the operation of the distributed power sources, etc. included in the first distributed power supply area 4, and also control the operation of the distributed power sources, etc. included in the second distributed power supply area 5. In this case, the energy management device 2 can calculate the power supply and demand difference by communicating with the distributed power supply area management device 41A, taking into account the power supply and demand for the power transmission and distribution network 6 in each second distributed power supply area 5 and the power supply and demand of the distributed power sources (PV, BT, DG, etc.) in each second distributed power supply area 5. In addition, by communicating with the distributed power source area management device 41A, the difference between power supply and demand can be calculated taking into account the supply and demand of power to the power transmission and distribution network 6 in each first distributed power source area 4 and the supply and demand of power of distributed power sources (PV, BT, DG, etc.) within each first distributed power source area 4.

[0077] In this case, the distributed power supply area management device 41A can have the functions of both the first distributed power supply area management device 41 and the second distributed power supply area management device 51 described above, and can communicate with the energy management device 2 related to both functions.

[0078] 15 , the energy management device 2 may have a second distributed power source area management device 51 that manages multiple second distributed power source areas 5. In this case, the energy management device 2 can calculate the difference between power supply and demand, taking into account the supply and demand of power to the power transmission and distribution network 6 in each second distributed power source area 5 and the supply and demand of power of distributed power sources (PV, BT, DG, etc.) in each second distributed power source area 5.

[0079] Although the main power source 3 in the above disclosure is described as having a plurality of synchronous generators 32, there may be one or more synchronous generators 32. As described above, the energy management device 2, energy management system 1, energy management method, and energy management program of the present disclosure can provide a stable supply of power to the entire power transmission and distribution network 6 even when a distributed power source area connected to the power transmission and distribution network 6 is disconnected due to a power outage or isolated operation, or when the area is subsequently reconnected due to a request for reconnection, etc.

[0080] The operational flows and operational examples in the above-described embodiments do not necessarily have to be executed in chronological order according to the order depicted in the flow diagrams or sequence diagrams. For example, steps in the operations may be executed in an order different from that depicted in the flow diagrams or sequence diagrams, or may be executed in parallel. Some steps in the operations may be deleted, or additional steps may be added to the processing. The operational flows and operational examples in the above-described embodiments may be executed independently, or two or more operational flows and operational examples may be combined and executed. For example, some steps in one operational flow may be added to another operational flow, or some steps in one operational flow may be replaced with some steps in another operational flow.

[0081] A program may be provided that causes a computer to execute the operations according to the above-described embodiments. The program may be recorded on a computer-readable medium. The computer-readable medium can be used to install the program on a computer. Here, the computer-readable medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, and may be, for example, a recording medium such as a CD-ROM or a DVD-ROM.

[0082] As used in this disclosure, the terms "based on" and "depending on" do not mean "based only on" or "depending only on," unless expressly stated otherwise. The term "based on" means both "based only on" and "based at least in part on." Similarly, the term "depending on" means both "depending only on" and "depending at least in part on." Furthermore, the terms "include," "comprise," and variations thereof do not mean including only the listed items, but may include only the listed items, or may include additional items in addition to the listed items. Furthermore, the term "or" as used in this disclosure is not intended to mean an exclusive or. In this disclosure, when articles are added by translation, such as a, an, and the in English, these articles are intended to include the plural unless the context clearly indicates otherwise.

[0083] The above describes the embodiments in detail with reference to the drawings, but the specific configuration is not limited to that described above, and various design changes can be made within the scope that does not deviate from the gist of the invention.

[0084] The following additional notes are about the features of the above-described embodiment.

[0085] (Appendix 1) a communication unit that communicates with a trunk power management device that manages a trunk power source connected to the power transmission and distribution network, and communicates with each of the distributed power management devices in the first and second distributed power source areas, each of which has one or more distributed power sources; a control unit that, when notified of the disconnection or grid connection of a first distributed power source area to the power transmission and distribution network, derives a power supply and demand difference that is a difference between power demand and power supply in the power transmission and distribution network after the disconnection or grid connection; The communication unit notifies at least one of the core power management device and the distributed power management device of the second distributed power area that is grid-connected to the power transmission and distribution network of first information indicating a change in the supply of power that will eliminate the difference in power supply and demand.

[0086] (Appendix 2) The notification of parallel-off or grid connection is a notification of parallel-off, the second distributed power supply area has at least one distributed power supply device selected from a power storage device and an emergency power generator, When the difference between power supply and demand indicates a supply shortage, the first information includes allocating a required output increase amount to an operating synchronous generator in the main power source, the power storage device, and the emergency generator in that order, at an output equal to or less than an upper limit output of each of the synchronous generators. 10. The energy management device of claim 1.

[0087] (Appendix 3) When the first information includes allocating an increased output to the power storage device or the emergency generator, the control unit notifies the main power source of second information, which further includes increasing the number of operating synchronous generators. 3. The energy management device according to claim 1 or 2.

[0088] (Appendix 4) In the second information for the main power supply, the output of the synchronous generator includes an output increase for charging the power storage device that is discharging based on the first information. 4. An energy management device according to any one of claims 1 to 3.

[0089] (Appendix 5) The notification of parallel-off or grid connection is a notification of parallel-off, the second distributed power supply area has at least one distributed power supply device selected from a power storage device and a solar power generation device, When the difference between power supply and demand indicates an oversupply, the first information includes allocating a required output reduction amount to a synchronous generator in operation in the main power source, the power storage device, and the solar power generation device in that order, with the synchronous generator being at or above a lower limit output and the power storage device being at or below an upper limit charge amount per hour. 5. An energy management device according to any one of claims 1 to 4.

[0090] (Appendix 6) 6. The energy management device according to any one of appendixes 1 to 5, wherein, when the first information includes allocating an output reduction to the power storage device or the solar power generation device, the control unit notifies the main power source of second information, which further includes reducing the number of operating synchronous generators.

[0091] (Appendix 7) In the second information for the main power source, the output of the synchronous generator includes an output reduction taking into account the discharge amount of the power storage device that is charged based on the first information. 7. An energy management device according to any one of claims 1 to 6.

[0092] (Appendix 8) the control unit causes each distributed power supply device in the second distributed power supply area to operate according to an operation plan that was in place prior to the notification of the first information, at a timing when the main power supply implements the content of the second information. 8. An energy management device according to any one of appendices 3, 4, 6 and 7.

[0093] (Appendix 9) The notification of parallel-off or grid connection is a notification of grid connection, the second distributed power supply area has at least one distributed power supply device selected from a power storage device and an emergency power generator, the power supply and demand difference is derived as a power storage device that is discharging when the power storage device in the first distributed power source area is in a fully charged state, and as a power storage device that is charging when the power storage device is in an empty-charge state; When the difference between power supply and demand indicates a supply shortage, the first information includes allocating a required output increase amount to an operating synchronous generator in the main power source, the power storage device, and the emergency generator in that order, at an output equal to or less than an upper limit output of each of the synchronous generators. 9. An energy management device according to any one of claims 1 to 8.

[0094] (Appendix 10) When the allocation does not satisfy the required output increase amount, the first information further includes increasing the number of operating synchronous generators. 10. An energy management device according to any one of claims 1 to 9.

[0095] (Appendix 11) The notification of parallel-off or grid connection is a notification of grid connection, the second distributed power supply area has at least one distributed power supply device selected from a power storage device and a solar power generation device, the power supply and demand difference is derived as a power storage device that is discharging when the power storage device in the first distributed power source area is in a fully charged state, and as a power storage device that is charging when the power storage device is in an empty-charge state; When the difference between power supply and demand indicates an oversupply, the first information includes allocating a required output reduction amount to a synchronous generator in operation in the main power source, the power storage device, and the solar power generation device in that order, with the synchronous generator being at or above a lower limit output and the power storage device being at or below an upper limit charge amount per hour. 11. An energy management device according to any one of claims 1 to 10.

[0096] (Appendix 12) When the allocation does not satisfy the required output reduction amount, the first information further includes reducing the number of operating synchronous generators. 12. The energy management device of claim 11.

[0097] (Appendix 13) 13. The energy management device according to claim 10, wherein, when the first information includes a change in the number of operating synchronous generators, the first distributed power supply area is connected to a grid at the time when the number of operating synchronous generators changes.

[0098] (Appendix 14) An energy management device according to any one of Supplementary Notes 1 to 13; a distributed power supply management device that manages the distributed power supplies in at least the second distributed power supply area; and a core power supply management device that manages the core power supply.

[0099] (Appendix 15) communicates with a core power management device that manages a core power source connected to the power transmission and distribution network, and communicates with each of the distributed power management devices in the first and second distributed power source areas, each of which has one or more distributed power sources; When the disconnection or grid connection of the first distributed power source area to the power transmission and distribution network is notified, a power supply and demand difference is calculated, which is the difference between the demand and supply of power in the power transmission and distribution network after the disconnection or grid connection; The energy management method, wherein the communication notifies at least one of the core power management device and the distributed power management device of the second distributed power area that is grid-connected to the power transmission and distribution network of first information indicating a change in power supply that will eliminate the difference between power supply and demand.

[0100] (Appendix 16) communicating with a trunk power management device that manages a trunk power source connected to the power transmission and distribution network, and communicating with respective distributed power management devices in first and second distributed power source areas each having one or more distributed power sources; When the disconnection or grid connection of the first distributed power source area to the power transmission and distribution network is notified, deriving a power supply and demand difference that is the difference between the demand and supply of power in the power transmission and distribution network after the disconnection or grid connection; The communication includes notifying at least one of the core power management device and a distributed power management device of the second distributed power area that is grid-connected to the transmission and distribution network of first information indicating a change in power supply that will eliminate the difference in power supply and demand. [Explanation of symbols]

[0101] 1 Energy Management System 2 Energy management device 21 Control Unit 211 CPU 212 Volatile memory unit 213 Non-volatile memory unit 22 Communications Department 3. Main power source 31 Core power management device 32 Synchronous generator 33 Synchronous generator switch 34 Communication lines 4. Distributed Power Source Area 1 41 First Distributed Power Supply Area Management Device 42 Solar power generation equipment 421 PV switch 422 PV control device 423 Solar Panels 424 PV inverter 43 Energy storage device 431 BT Switch 432 BT control device 433 Storage Battery 434 BT inverter 44 Emergency generator 441 DG switch 442 DG control device 443 Small Diesel Generator 444 DG power conversion section 45 Load 451 Load switch 47 First Distributed Power Supply Area Switch 48 Communication Networks 49 1st distributed power supply power line 5. Second Distributed Power Source Area 51 Second distributed power supply area control device 52 Solar power generation equipment 53 Energy storage device 54 Emergency generator 55 Load 551 Load switch 57 Second distributed power supply area switch 58 Communication Networks 59 2nd distributed power supply power line 6. Power transmission and distribution network 7. Communication Networks

Claims

1. a communication unit that communicates with a trunk power management device that manages a trunk power source connected to the power transmission and distribution network, and communicates with each of the distributed power management devices in the first and second distributed power source areas, each of which has one or more distributed power sources; a control unit that, when notified of the disconnection or grid connection of the first distributed power source area to the power transmission and distribution network, derives a power supply and demand difference that is a difference between power demand and power supply in the power transmission and distribution network after the disconnection or grid connection; The communication unit notifies at least one of the core power management device and the distributed power management device in the second distributed power source area that is grid-connected to the power transmission and distribution network of first information indicating a change in the supply of power that will eliminate the difference in power supply and demand.

2. The notification of parallel-off or grid connection is a notification of parallel-off, the second distributed power supply area has at least one distributed power supply device selected from a power storage device and an emergency power generator, When the difference between power supply and demand indicates a supply shortage, the first information includes allocating a required output increase amount to an operating synchronous generator in the main power source, the power storage device, and the emergency generator in that order, at an amount equal to or less than an upper limit output of each of the synchronous generators. The energy management device of claim 1 .

3. When the first information includes allocating an increased output to the power storage device or the emergency generator, the control unit notifies the main power source of second information that further includes increasing the number of operating synchronous generators. The energy management device of claim 2 .

4. the second information for the main power supply includes an output increase for the synchronous generator to charge the power storage device that is discharging based on the first information; The energy management device of claim 3 .

5. The notification of parallel-off or grid connection is a notification of parallel-off, the second distributed power supply area has at least one distributed power supply device selected from a power storage device and a solar power generation device, When the difference between power supply and demand indicates an oversupply, the first information includes allocating a required output reduction amount to a synchronous generator in operation in the main power source, the power storage device, and the solar power generation device in that order, with the synchronous generator being allocated an output equal to or greater than a lower limit, and the power storage device being allocated an amount equal to or less than an upper limit charge amount per hour. The energy management device of claim 1 .

6. 6. The energy management device according to claim 5, wherein, when the first information includes allocating an output reduction to the power storage device or the solar power generation device, the control unit notifies the main power source of second information further including reducing the number of operating synchronous generators.

7. In the second information for the main power source, the output of the synchronous generator includes an output reduction taking into account the discharge amount of the power storage device that is charged based on the first information. The energy management device of claim 6 .

8. the control unit causes each distributed power supply device in the second distributed power supply area to operate according to an operation plan that was in place prior to the notification of the first information, at a timing when the main power supply implements the content of the second information.

8. An energy management device according to any one of claims 3, 4, 6 and 7.

9. The notification of parallel-off or grid connection is a notification of grid connection, the second distributed power supply area has at least one distributed power supply device selected from a power storage device and an emergency power generator, the power supply and demand difference is derived as a power storage device that is discharging when the power storage device in the first distributed power source area is in a fully charged state, and as a power storage device that is charging when the power storage device is in an empty-charge state; When the difference between power supply and demand indicates a supply shortage, the first information includes allocating a required output increase amount to an operating synchronous generator in the main power source, the power storage device, and the emergency generator in that order, at an amount equal to or less than an upper limit output of each of the synchronous generators. The energy management device of claim 1 .

10. When the allocation does not satisfy the required output increase amount, the first information further includes increasing the number of operating synchronous generators. The energy management device of claim 9.

11. The notification of parallel-off or grid connection is a notification of grid connection, the second distributed power supply area has at least one distributed power supply device selected from a power storage device and a solar power generation device, the power supply and demand difference is derived as a power storage device that is discharging when the power storage device in the first distributed power source area is in a fully charged state, and as a power storage device that is charging when the power storage device is in an empty-charge state; When the difference between power supply and demand indicates an oversupply, the first information includes allocating a required output reduction amount to a synchronous generator in operation in the main power source, the power storage device, and the solar power generation device in that order, with the synchronous generator being allocated an output equal to or greater than a lower limit, and the power storage device being allocated an amount equal to or less than an upper limit charge amount per hour. The energy management device of claim 1 .

12. When the allocation does not satisfy the required output reduction amount, the first information further includes reducing the number of operating synchronous generators. The energy management device of claim 11.

13. 13. The energy management device according to claim 10, wherein, when the first information includes a change in the number of operating synchronous generators, the first distributed power source area is connected to a grid at a timing when the number of operating synchronous generators changes.

14. a trunk power supply management device that manages a trunk power supply connected to the power transmission and distribution network; a distributed power supply management device for each of first and second distributed power supply areas, each of which has one or more distributed power supplies; an energy management device including a communication unit that communicates with the core power management device and the distributed power management device, and a control unit that, when notified of disconnection or grid connection of the first distributed power source area to the power transmission and distribution network, derives a power supply and demand difference that is the difference between power demand and power supply in the power transmission and distribution network after the disconnection or grid connection; an energy management system in which the energy management device notifies at least one of the core power management device and the distributed power management device in the second distributed power source area that is grid-connected to the power transmission and distribution network of first information indicating a change in the supply of power that will eliminate the difference in power supply and demand.

15. communicates with a core power management device that manages a core power source connected to the power transmission and distribution network, and communicates with each of the distributed power management devices in first and second distributed power source areas, each of which has one or more distributed power sources; When the disconnection or grid connection of the first distributed power source area to the power transmission and distribution network is notified, a power supply and demand difference is derived, which is the difference between the demand and supply of power in the power transmission and distribution network after the disconnection or grid connection; An energy management method in which the communication notifies at least one of the core power management device and the distributed power management device in the second distributed power source area that is grid-connected to the power transmission and distribution network of first information indicating a change in power supply that will eliminate the difference between power supply and demand.

16. communicating with a trunk power management device that manages a trunk power source connected to the power transmission and distribution network, and communicating with respective distributed power management devices in first and second distributed power source areas each having one or more distributed power sources; When the disconnection or grid connection of the first distributed power source area to the power transmission and distribution network is notified, deriving a power supply and demand difference that is a difference between power demand and power supply in the power transmission and distribution network after the disconnection or grid connection; The communication includes notifying at least one of the core power management device and the distributed power management device in the second distributed power source area that is grid-connected to the transmission and distribution network of first information indicating a change in power supply that will eliminate the difference in power supply and demand.

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