JP2008104269A - System for managing demand and supply in micro grid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system for managing a demand and a supply in a micro grid which acquires information on a plurality of apparatuses at a time in addition to a condition confirmation, and stabilizes power supplied within the micro grid in comparison with conventional cases. <P>SOLUTION: The system for managing the demand and the supply in the micro grid has an information collectively-acquiring means 81, and a demand/supply controlling means 82. Since the information collectively-acquiring means 81 implements a multicast communication and collectively acquires the information on the apparatuses belonging to a group, the information on a plurality of the apparatuses can be acquired at a time in addition to the condition confirmation. The demand/supply controlling means 82 controls disconnections or connections of loads in each load group by using the multicast communication so as to prevent the magnitude of the loads 60, 61, 62, 63, 64, 65 connected within the micro grid 31 from being large than outputs from a plurality of distributed power supplies. A plurality of the loads are disconnected/connected at a time. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a supply and demand management system for a microgrid that can be connected to a commercial system and manages the supply and demand of a microgrid having a plurality of distributed power sources and a plurality of loads.

  A microgrid is a small-scale system with multiple distributed power sources and multiple loads. The multiple distributed power sources are collectively controlled via a communication network and can be operated independently from existing commercial systems. It is a site-type power supply system. Such a microgrid constitutes a communication network with a load measuring device, a distributed power source control device, a distributed power source output measuring device, and the like. Then, the network setting of each device and the registration to the control device (supply / demand management server) that controls the supply / demand of power within the microgrid are manually performed. The supply and demand control program is also manually customized to match the current load, distributed power supply, and distribution line configuration. In such a method, it is necessary to manually register and change a program each time a load or a distributed power source is introduced or abolished.

In order to reduce the labor required for the above-described registration / program change, a method of applying the technique described in Patent Document 1 to a microgrid can be considered. That is, when a distributed power source or a load is connected to a system in the microgrid, an identification code is automatically acquired, and registration / deletion is performed depending on whether the status check succeeds or fails.
JP 2001-320754 A

  However, in the technology to which the above-described method is applied, in order to obtain information on the distributed power source and the load (for example, the power source capacity and the load capacity), the state confirmation must be accessed separately. It must also be individually connected or disconnected. There are not a few types of distributed power sources (for example, solar cells and wind power generators) that vary greatly depending on weather conditions, and the power that can be supplied may vary greatly. If the load is larger than the capacity of the distributed power supply, the power supply may become unstable throughout the microgrid.

  The present invention has been made in view of the above points, and it is possible not only to check the status but also to obtain information related to a plurality of devices at a time, and to stabilize the power supply in the microgrid as compared with the prior art. An object of the present invention is to provide a microgrid supply and demand management system.

(1) Means for solving a problem (hereinafter simply referred to as “solution means”) 1 is a micro that can be connected to a commercial system and manages the supply and demand of a microgrid having a plurality of distributed power sources and a plurality of loads. A grid supply and demand management system, wherein a plurality of distributed power sources belonging to a power supply group and a plurality of loads grouped into two or more load groups are set with different multicast addresses for each group, Information is obtained from the commercial system based on the information obtained by the information collective acquisition means and the information collective acquisition means for obtaining information of each device belonging to the accessed group collectively by accessing each group by multicast communication The size of the load connected in the state microgrid is the output of the plurality of distributed power sources. Even so it does not increase, and gist and a supply control means for controlling the cut-off or connection of the load for each of the load groups via multicast communication.

  According to the solution 1, the information batch acquisition unit acquires the information of each device belonging to the group in a batch by performing multicast communication with the multicast address. Therefore, it is possible to obtain information related to a plurality of devices at a time in addition to the state confirmation. On the other hand, if the total load connected to the system in the microgrid is larger than the output of the distributed power supply, the supply and demand control means uses a plurality of loads constituting a load group by multicast communication (simultaneous communication) Since the power supply is cut off at a time, the power supply in the microgrid can be stabilized more than in the prior art.

(2) The solving means 2 is the microgrid supply and demand management system described in the solving means 1, in which different priorities are set for two or more load groups, and the supply and demand control means sets a low priority. The gist of the present invention is to perform control for blocking the connection of the load for the load group.

  The priority setting method is arbitrary. For example, it is set according to the magnitude of the load in the load group, or according to the importance of the load (for example, a hospital or a public institution). According to the solving means 2, since the supply and demand control means cuts off the connection from the load group for which the low priority is set, the connection is maintained for the load group for which the high priority is set. Therefore, it is possible to prevent the power supply of the microgrid from becoming unstable while maintaining the connection of a load having a high priority.

  According to the present invention, since a plurality of loads constituting a load group are blocked at a time by multicast communication, the power supply in the microgrid can be stabilized more than before.

  The best mode for carrying out the present invention will be described with reference to FIGS. FIG. 1 schematically shows a configuration example of a microgrid. FIG. 2 is a flowchart showing an example of a procedure for supply and demand control processing. 3 and 4 show an example of the priority list.

  FIG. 1 shows an example in which three microgrids 30, 31, 32 are connected to the commercial system 10. The commercial system 10 and the microgrid 30 are connected by a connection line L1, and a switch 20 (also referred to as a circuit breaker; the same applies hereinafter) 20 is provided in the middle of the connection line L1. Similarly, the commercial system 10 and the microgrids 31 and 32 are connected by connecting lines L2 and L3, respectively, and switches 21 and 22 for connecting / disconnecting are provided in the middle of the connecting lines L2 and L3. The microgrids 30, 31, and 32 are the same in that they have a plurality of distributed power sources and a plurality of loads, but the specific quantities are generally different. Hereinafter, the microgrid 31 will be described as a representative for the sake of simplicity.

  The microgrid 31 shown in FIG. 1 includes three distributed power sources (solar cell 70, wind power generator 71 and fuel cell 72), six loads 60, 61, 62, 63, 64, 65, a supply and demand control server 80, and the like. Have Each distributed power source and load are connected to the private line 40 together with the connecting line L2. However, the load 60 interposes a switch 50 for connecting / disconnecting to / from the private line 40. Similarly, the switches 61, 62, 63, 64, and 65 are provided with switches 51, 52, 53, 54, and 55 for connecting / disconnecting to and from the private line 40.

  The supply and demand control server 80 is a network N (represented by a two-dot chain line in FIG. 1) in order to be able to communicate with each distributed power source and load, as well as the switches 50, 51, 52, 53, 54, and 55. Connecting. This network N is a network capable of multicast communication such as IPv6. The supply and demand control server 80 includes an information acquisition unit 81, a supply and demand control unit 82, a recording unit 90, and the like. A control example of the supply and demand control server 80 will be described later (FIG. 2).

  The information acquisition unit 81 accesses each group by multicast communication, and collectively acquires information on the distributed power source and the load (that is, the constituent elements of the group) belonging to each group. The group corresponds to a power supply group including the solar cell 70, the wind power generator 71, and the fuel cell 72, and a load group in which the loads 60, 61, 62, 63, 64, and 65 are grouped into two or more. The supply and demand control unit 82 performs load blocking or connection control for each load group by multicast communication so that the magnitude of the load connected in the microgrid 31 does not become larger than the output of the power supply group. The recording unit 90 corresponds to, for example, a memory or a disk recording device, and records a priority list in advance in order to set a priority for each load group.

  In the supply and demand control server 80 configured as described above, an example procedure for supply and demand control will be described with reference to FIG. The supply and demand control process shown in FIG. 2 is repeated in real time while the power supply of the supply and demand control server 80 is on.

  Here, different multicast addresses are set in advance for each group. That is, different multicast addresses are set for the power supply group including the solar cell 70, the wind power generator 71, and the fuel cell 72, and each of the load groups divided into two or more groups. More specifically, a multicast address is set for each device (power supply, load, etc.). The grouping method is arbitrary, for example, according to the type of load (for example, industrial or residential use), according to the size of the load, according to the importance of the load (for example, hospital or public institution), etc. Is applicable. In FIG. 1, for example, load group A is represented by “(A)”, load group B is represented by “(B)”, and the like in FIG.

  In addition, the same address as the multicast address set for each load group is set in the switches 50, 51, 52, 53, 54, and 55 interposed between the private line 40 and each load. That is, “2” is set for the switch 50, “3” is set for the switches 51, 52, and 54, and “4” is set for the switches 53 and 55.

  In the supply and demand control process of FIG. 2, first, when performing multicast communication, the multicast address for access is switched [step S10], and the distributed power supply and load information belonging to each group is acquired collectively by the multicast communication [step S11]. This collective acquisition is repeated until all devices in the microgrid 31 are accessible (YES in step S12). In the collective acquisition of information in step S11, the capacity, connection state, operation status (output), etc. are obtained for each device of the distributed power source and the load. That is, not only the status of the apparatus but also information on a plurality of apparatuses can be obtained at a time.

  Based on the information obtained in step S11, if the load applied to the entire load group exceeds the output of the distributed power supply applied to the power supply group (YES in step S13), the distributed power supply applied to the power supply group is determined. It is checked whether the capacity is still sufficient [step S14]. If the capacity of the distributed power supply for the power supply group is still sufficient (YES in step S14), the output of the power supply group is increased [step S15].

  On the other hand, if the capacity of the distributed power supply for the power supply group is not sufficient (NO in step S14), the lowest priority is set among the active load groups according to the priority list recorded in the recording unit 90. A signal by multicast communication is output to the switch in the load group to cut off the load [step S20]. The interruption of the load may be all the loads constituting the target load group, or may be a part of the loads so that the magnitude of the load is within the total capacity of the power supply group.

  Here, an example of the priority list will be described with reference to FIGS. The priority list 91 shown in FIG. 3 is an example set according to the importance of the load, and the priority list 92 shown in FIG. 4 is an example set according to the magnitude of the load in the load group.

  The priority list 91 is grouped into three load groups A, B, and C in order of load importance. In order of importance, the load group A includes only the load 60, the load group B includes the loads 61, 62, and 64, and the load group C includes the loads 63 and 65. The priority is set to 1, 2, and 3 in the order of load groups A, B, and C. For example, when the load group C is shut off in step S20, the supply and demand control server 80 simultaneously outputs a signal for shutting down by multicast communication to the multicast address for which “4” is set.

  The priority list 92 is grouped into four load groups A, B, C, and D so that the total capacity is in descending order. In order from the largest total capacity, load group A is composed of loads 65 and 62, load group B is composed of only load 60, load group C is composed of only load 63, and load group D is composed of loads 61 and 64. The priorities are set to 1, 2, 3, and 4 in the order of load groups B, C, A, and D, respectively.

Returning to FIG. 2, when the load applied to the entire load group does not exceed the output of the distributed power supply applied to the power supply group (NO in step S13), and the load can be added and connected. (YES in step S30), a load group or a load is added within a range not exceeding the output of the distributed power source applied to the power source group [step S31]. How to add is arbitrary. For example, even if the entire load group is added, the entire load group is added if it falls within the range of the total capacity of the power supply group, and if it does not fit, a part of the load group is added. When the power capacity is sufficient, the load to be connected can be increased.
If the load applied to the entire load group does not exceed the output of the distributed power supply applied to the power supply group (NO in step S13) and exceeds the total capacity of the power supply group, an additional load cannot be connected. (NO in step S30), nothing is performed.

  Thereafter, when the supply and demand control is continued (YES in step S16), the process returns to step S10 to continue the execution in order to obtain information on the entire microgrid 31. On the other hand, when the supply and demand control is not continued (NO in step S16), the supply and demand control process is terminated. Thus, the supply and demand control process is executed in real time.

According to the embodiment described above, the following effects can be obtained.
(1) A different multicast address is set for each group (see FIG. 1), and information on distributed power sources and loads belonging to each group is acquired collectively by multicast communication (steps S10 to S12 in FIG. 2; information acquisition) Equivalent to means 81). Therefore, it is possible to obtain information related to a plurality of devices at a time in addition to the state confirmation. Further, when the load 60, 61, 62, 63, 64, 65 connected to the self-supported line 40 in the microgrid 31 is larger than the output of the solar cell 70, the wind power generator 71 and the fuel cell 72 ( 2), a plurality of loads constituting the load group were blocked at once by multicast communication (step S20 in FIG. 2; corresponding to the supply and demand control means 82). Therefore, the power supply in the microgrid 31 can be stabilized more than before.

(2) Since the control is performed so that the connection is cut off from the load group for which the low priority is set (step S20 in FIG. 2; corresponding to the supply and demand control means 82), the load group for which the high priority is set maintains the connection. Is done. Therefore, it is possible to prevent the power supply of the microgrid 31 from becoming unstable while maintaining the connection of a load having a high priority.

[Other Embodiments]
Although the best mode for carrying out the present invention has been described above, the present invention is not limited to this mode. In other words, the present invention can be implemented in various forms without departing from the gist of the present invention. For example, the following forms may be realized.

(1) In the above-described embodiment, the solar cell 70 (that is, the solar power generation device), the wind power generator 71, and the fuel cell 72 are applied as the plurality of distributed power sources (see FIG. 1). Instead of (or in addition to) this form, a micro gas turbine, a power storage device, a biomass power generation device, a wave power generation device, a waste power generation device, or the like is applicable. Although three machines are connected in the example of FIG. 1, it is desirable to connect as many distributed power sources as possible regardless of the type in terms of securing a large capacity of the distributed power sources. As the number of distributed power sources that can be connected increases, the stability of power supply in the microgrid 31 increases.

(2) In embodiment mentioned above, it was set as the structure which connects between the commercial system | strain 10 and the microgrids 30, 31, and 32 by connection line L1, L2, L3, respectively (refer FIG. 1). In addition to this configuration, the microgrids 30, 31, 32 may be directly connected to each other. In this way, power can be exchanged between the microgrids when necessary.

(3) Although the loads are grouped in the above-described embodiment (see FIGS. 3 and 4), the distributed power sources may be grouped. For example, it can be divided into distributed power sources that cannot control output (solar cells, wind power generators, etc.) and distributed power sources that can control output (fuel cells, gas engine cogeneration, etc.). Or for housing), or so that the capacity of the power source is almost equal. In the case of grouping according to whether output control is possible, it is possible to easily identify a power source capable of output control. In addition, the demand control process of FIG. 2 controls the connection / cutoff of the load assuming that the power capacity is constant, but the connection / cutoff of the distributed power supply is assumed assuming that the load is constant in the same manner as this process. Make control. Furthermore, it is desirable to set the priority for each group as in the case of load. If the distributed power sources are grouped in this way, the power source capacity supplied to the private line 40 can be controlled to be substantially constant, or the power source capacity can be adjusted to meet the load demand.

(4) In embodiment mentioned above, it was set as the structure which provided the private line 40 (system | strain, electric power line) and the network N (communication line, communication network) separately (refer FIG. 1). It replaces with this form and the structure which serves as the network N with the private line 40, ie, power line communication (PLC; Power Line Communication), may be comprised. In this way, the cost for constructing the network N can be omitted, and the overall cost can be kept low.

(5) In the above-described embodiment, multicast information is set in advance when acquiring information on distributed power sources and loads belonging to each group by multicast communication (see step S11 in FIG. 2) (see FIG. 2). 1). Instead of this form, the supply and demand control server 80 may include address setting means for setting a multicast address for each device (power supply, load, etc.) based on the identification information. In this way, it is not necessary to set a multicast address in advance for each device, so that the time and effort for setting can be saved.
Specifically, identification information is recorded in advance in the solar cell 70, the wind power generator 71, the fuel cell 72, and the loads 60, 61, 62, 63, 64, 65. This identification information is device-specific data and corresponds to, for example, an IP address or a model number. The supply and demand control server 80 divides the loads 60, 61, 62, 63, 64, 65 into two or more groups based on the identification information, and further multicasts to each device (power supply, load, etc.) so as to have different addresses for each group. Set the address.

It is a figure which represents typically the structural example of a microgrid. It is a flowchart showing the example of a procedure of supply-and-demand control processing. It is a figure showing an example of a priority list. It is a figure showing an example of a priority list.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Commercial system 20, 21, 22 Switch 30, 31, 32 Microgrid 40 Self-supported line 50, 51, 52, 53, 54, 55 Switch 60, 61, 62, 63, 64, 65 Load 70 Solar cell (distribution) Type power supply)
71 Wind power generator (distributed power supply)
72 Fuel cell (distributed power supply)
80 Supply / Demand Control Server 81 Information Acquisition Unit 82 Supply / Demand Control Unit 90 Recording Unit 91, 92 Priority List L1, L2, L3 Connection Line

Claims (2)

A microgrid supply and demand management system that can be connected to a commercial system and manages the supply and demand of a microgrid having a plurality of distributed power sources and a plurality of loads,
A different multicast address is set for each group for the plurality of distributed power sources belonging to the power group and the plurality of loads grouped into two or more load groups,
Information batch acquisition means for accessing each group by multicast communication, and collectively acquiring information of each device belonging to the accessed group;
Based on the information acquired by the information batch acquisition means, so that the size of the load connected in the microgrid in a state disconnected from the commercial system does not become larger than the output of the plurality of distributed power sources, A supply and demand management system for a microgrid, comprising supply and demand control means for controlling load blocking or connection for each load group by multicast communication. A microgrid supply and demand management system according to claim 1,
Set different priorities for two or more load groups,
The supply and demand control means is a microgrid supply and demand management system that performs control to cut off load connection for a load group with a low priority.

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