JP2016025799A - System supervisory control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce inconvenience of a user as well as prevent overload at the time of power return.SOLUTION: A calculation unit, on the basis of information on a plurality of transfer switches, determines a plurality of transfer path candidates, each of which is a candidate for a transfer path including a transfer switch between a power return section and a power distribution line other than a specific power distribution line of a plurality of power distribution lines; calculates, for each transfer path candidate of the plurality of transfer path candidates, preparation power, which is an amount of power capable of being increased in addition to power being supplied to the transfer path candidate; calculates, as demand power, the sum of power consumption of loads before an accident in the power return section; and selects, as a transfer path, a transfer path candidate having preparation power larger than the demand power from the plurality of transfer path candidates. A communication unit transmits a switch-on instruction to a transfer switch included in the selected transfer path to transfer power to the power return section through the transfer path.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a system monitoring control technique for monitoring and controlling a distribution system.

  In a power distribution system in which a load and a distributed power source such as a photovoltaic power generation facility coexist, when a power failure occurs due to an accident, the distributed power source automatically stops for safety. After that, even if an accident recovery operation is performed, it takes time to start the distributed power supply. Therefore, there is a risk of a power failure due to an overload at the moment of the accident recovery operation.

  Patent Document 1 discloses a power distribution system that restores an accident by inserting a distribution line breaker of a distribution line in which a distributed power source exists in a state where the load of a specific consumer is interrupted so that the distribution line does not become overloaded. A supervisory control device is described.

Japanese Patent No. 4711651

  In the technique of Patent Document 1, since the load of the specific customer is not linked until the distributed power source is restored, the power outage state of the specific customer is prolonged and inconvenience is imposed. A small distributed power supply for which the automatic recovery function is effective can be recovered in a few minutes. However, since a large distributed power supply is manually recovered by an administrator, a power outage state of a specific consumer may take several hours. An object of the present invention is to provide a power interchange means for evenly restoring power to each consumer when a power outage due to an accident occurs in a power distribution system in which a load and a distributed power source such as a photovoltaic power generation facility coexist. To do.

  In order to solve the above-described problem, a system monitoring and control device according to the present invention is a versatile switch in which each of a plurality of distribution lines is connected to a power system, and is normally opened between the plurality of distribution lines. System monitoring control for monitoring and controlling the plurality of distribution lines, each of which includes a plurality of sections that can be divided by a plurality of distribution switches that are normally inserted. A communication unit that receives power consumption of a load connected to a section in the plurality of distribution lines and generated power of a distributed power source connected to a section in the plurality of distribution lines; When an accident in the plurality of distribution lines is detected, a calculation unit that identifies the section in which the accident has occurred as an accident section, and selects a section other than the accident section as a power recovery section in the distribution line including the accident section And comprising. The communication unit disconnects between the accident section and the power recovery section by transmitting an opening instruction to a switch for distribution between the accident section and the power recovery section, A plurality of candidates for an accommodation path including an accommodation switch between a distribution line other than the specific distribution line and the power recovery section in the plurality of distribution lines based on information on the plurality of exchange switches And determining a reserve capacity that is an increase in power supplied to the accommodation path candidate for each of the accommodation path candidates of the plurality of accommodation path candidates. The total power consumption of the load in the power recovery section is calculated as demand power, and an accommodation path candidate having reserve capacity larger than the demand power is selected as an accommodation path among the plurality of accommodation path candidates, and the communication unit The switch for accommodation included in the accommodation path By transmitting an indication of the input, to interchange power from the interchange path to the power recovery section.

  ADVANTAGE OF THE INVENTION According to this invention, while preventing the overload at the time of a power recovery, the inconvenience of the consumer by a power failure can be reduced.

The structure of the power distribution system of an Example is shown. The function structure of the power distribution system monitoring and control apparatus 500 is shown. The operation of the power interchange method calculation means 505 is shown. A power interchange route candidate list 614 is shown. The operation of the power monitoring means 511 during power interchange is shown. The relationship between power interchange, demand control and power generation control is shown. A first specific example of the maximum power generation possible power grasping means 507 will be shown. A second specific example of the maximum power generation possible power grasping means 507 will be shown. A third specific example of the maximum power generation possible power grasping means 507 will be shown. The timing chart of a 1st case is shown. The timing chart of a 2nd case is shown.

  The present invention may be expressed by the following terms. The power system corresponds to the substation 301, the distribution substations 302, 303, and 304. The interchangeable switch corresponds to the air switches 351, 352, 352, 354, 355, 356, and the like. The power distribution switch corresponds to the air switches 311, 312, 313, and 314. The accommodation path corresponds to a power accommodation route or the like. The accommodation route candidate corresponds to a power accommodation route candidate or the like. The reserve power corresponds to the total reserve power Y1 + Y2. The system monitoring control device corresponds to the distribution system monitoring control device 500 and the like. The communication unit corresponds to the communication unit 553 and the like. The calculation unit corresponds to the calculation unit 552, the storage unit 551, and the like.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a configuration of a power distribution system of the embodiment.

  The substation 301 is connected to the upper substation and the distribution substations 302, 303, and 304. The voltage from the upper substation is lowered to 66 kV and transmitted to the distribution substations 302 to 304. In the following description, the upstream from the distribution substation 302-304 may be referred to as a power system, and the downstream from it may be referred to as a distribution system.

  The distribution substation 302 is connected to the upper substation and the distribution line, and further reduces the voltage to 6.6 kV and transmits power to the distribution line 802. On the distribution line 802, air switches 311 to 314 for distribution are installed in places. The air switches 311 to 314 are normally ON (turned on), but limit the power outage section to the minimum section when a power outage occurs. The distribution line 802 is connected downstream of the air switch 311 through a pole transformer 321 to a load of a general household in the area 401 and a small-sized photovoltaic power generation apparatus of less than 50 kW. A large-scale photovoltaic power generation apparatus 101 of 50 kW or more and less than 2 MW in the area 402 is connected to the downstream side of the air switch 312 in the distribution line 802 through the power receiving cubicle 111. Out of the distribution line 802, ordinary household loads 201, 202, 203 and small solar power generation devices 102, 103 in the area 403 are connected to the downstream of the air switch 313 through a pole transformer 322. Yes. Note that the number of general households and photovoltaic power generation devices connected to one pole transformer is usually larger than the number shown in this figure, but is omitted here.

  The distribution substation 303 is connected to the upper substation and the distribution line, and transmits the power to the distribution line 803 by reducing the voltage to 6.6 kV. A large load 204 such as a large photovoltaic power generation device 104 or a factory in the area 404 is connected to the distribution line 803 through the power receiving cubicle 112. The downstream distribution line 803 is connected to a general household load in the area 405 and small solar power generation devices 105 and 106 through a pole transformer 323.

  The distribution substation 304 is connected to the upper substation and the distribution line, and transmits the power to the distribution line 804 with the voltage lowered to 6.6 kV.

  The distribution lines 802 and 803 are connected by air switches 351 and 352 for power interchange. The distribution lines 803 and 804 are connected by air switches 353 and 356 for power interchange. The distribution lines 802 and 804 are connected by an air switch 355 for power interchange. The distribution line 802 and another distribution line (not shown) are connected by an air switch 354 for power interchange. The air switches 351, 352, 353, 354, 355, and 356 are normally in an OFF (open) state, and the distribution lines are disconnected. As described above, since each distribution line (branch line) is independent in normal times, there is an advantage that a power outage point at the time of a power outage can be quickly identified.

  The distribution system monitoring and control device 500 may be provided for each substation 301 at a business site that manages the substation 301 or may be provided at a central power supply command station. The distribution system monitoring control device 500 is connected to the substation 301 via the communication network 800. The distribution system monitoring and control device 500 is further connected to a distribution substation 302, 302, 304, an air switch in the downstream, a general household, a solar power generation device, a power receiving cubicle, a solar power generation device, etc. via a communication network 800. It is connected to the. The communication network 800 may be provided together with a power line, or may be another communication line such as the Internet or a wireless communication line.

  The distribution system monitoring and control device 500 receives measured values from loads and generators in the distribution lines 802, 803, and 804 under management, and detects an accident based on the measured values. Furthermore, the distribution system monitoring and control device 500 controls these by transmitting commands to the air switch, solar power generation device, and load when an accident is detected or recovered. The solar power generation device includes a solar power generation panel and a PCS (Power Conditioning Subsystem) that converts electric power generated by the solar power generation panel. The PCS receives a command from the distribution system monitoring and control device 500, controls the power output to the distribution line according to the command, and transmits a measurement value related to the power to the distribution system monitoring and control device 500.

  When a large number of solar power generation devices are used, the output of the solar power generation device may be suppressed in order to reduce changes in the voltage of the distribution line and the frequency of the entire power system. In the present embodiment, the power distribution system monitoring and control device 500 suppresses the output of the solar power generation device by transmitting the power generation suppression rate as a command to the solar power generation device.

  When the distribution system monitoring and control apparatus 500 detects an accident based on the voltage of the distribution line 802, it turns off all the air switches 311, 312, 313, and 314 on the distribution line 802. After that, the power distribution system monitoring and control device 500 adds the section to which power is supplied again by turning it on in order from the upstream air switch, and when an accident is detected again, the added section is the power outage section. Identified as (accident section).

  FIG. 2 shows a configuration of the power distribution system monitoring and control apparatus 500.

  The distribution system monitoring control device 500 is, for example, a computer, and includes a storage unit 551 such as a memory, a calculation unit 552 such as a CPU (Central Processing Unit), and a communication unit 553 such as a NIC (Network Interface Card). The storage unit 551 stores a program and data for the distribution system monitoring control function. The calculation unit 552 executes the distribution system monitoring control function according to the program and data stored in the storage unit 551. The communication unit 553 communicates with the communication network 800 in accordance with instructions from the calculation unit 552. A program for the distribution system monitoring control function may be stored in a computer-readable storage medium, and the computer may read the program from the storage medium.

  The distribution system monitoring and control device 500 functions as a power consumption monitoring unit 501, a distributed power generation power monitoring unit 502, a section power calculation unit 503, a section power database 504, a power interchange method calculation unit 505, and a maximum power generation. It includes a possible power grasping means 507, a switch operating means 508, a power generation suppression rate setting means 509, a demand restraint rate notification means 510, a power interchangeable power monitoring means 511, and a maximum transmittable power grasping means 512.

  The power consumption monitoring unit 501 receives measured values of power consumption via the communication network 800 and the communication unit 553 from loads in all sections under management such as the loads 201, 202, and 203. The distributed power generation power monitoring means 502 generates power from the distributed power source via the communication network 800 and the communication unit 553 from the distributed power sources of all sections under management such as the solar power generation devices 101, 102, 103, 104, 105, 106. Receive power measurements. The section power calculation means 503 calculates, for each section, the total power consumption that is the sum of the power consumption of the loads in the section, calculates the total generated power that is the sum of the generated power of the distributed power sources in the section, and the total consumption The value obtained by subtracting the total generated power from the power is calculated as demand power. In other words, the demand power in a certain section is the power that the section receives from outside the section. The section power calculation means 503 records the total power consumption, the total generated power, and the demand power in the section power database 504.

  The operations of the power consumption monitoring unit 501, the distributed power generation power monitoring unit 502, and the section power calculation unit 503 are always measured at regular intervals regardless of the occurrence of a power failure, and the section power database 504 is updated.

  The section power database 504 further stores an air switch in the distribution line and information on the air switch between the distribution lines.

  Maximum transmittable power grasping means 512 receives measured values of the maximum transmittable power and the current transmitted power from each of distribution substations 302, 303, and 304 via communication network 800 and communication unit 553. . The administrator may input the maximum transmittable power and the transmitted power notified from the power company or the like to the maximum transmittable power grasping means 512. The maximum power generation possible power grasping means 507 acquires the maximum power generation possible power that is the power that can be generated by the distributed power source via the communication network 800 and the communication unit 553. Details of the maximum power generation possible power grasping means 507 will be described later.

  When performing power accommodation, the power accommodation method calculation unit 505 reads the total power consumption immediately before a power failure in the power recovery section, which is a section subject to power recovery by power accommodation, from the section power database 504. In a case where a short circuit 801 occurs between the distribution line 802 and the pole transformer 321, the power recovery section is a section between the air switches 312 and 314 and includes areas 402 and 403. The power interchange method calculating unit 505 obtains the maximum transmittable power from the power system and the transmitted power from the maximum transmittable power grasping unit 512. Further, the power accommodation method calculation unit 505 obtains the maximum power that can be generated to the power recovery section from the maximum power generation grasping unit 507 and obtains the generated power of the distributed power source from the distributed power generation power monitoring unit 502. . The power accommodation method calculation means 505 selects a power accommodation route from these data. The switch operating means 508 executes power interchange by operating the air switch via the communication network 800 and the communication unit 553 according to the selected power interchange route. As a result, the conductive power increases from the electric power system to the distribution source distribution line, so that the power generation suppression rate setting means 509 is connected to the solar power generation device in the distribution source distribution line via the communication network 800 and the communication unit 553. An instruction to reduce the power generation suppression rate is transmitted. Further, when the power in the power recovery section cannot be covered only by power interchange, the demand restraint rate notifying unit 510 sends the load in the power recovery section or the distribution source power line via the communication network 800 and the communication unit 553. An instruction for suppressing power consumption of the connected load is transmitted.

  When the processing of the power interchange method calculation unit 505 is finished, the power monitoring unit 511 during power interchange starts its operation. The power interchanged power monitoring unit 511 monitors the total power consumption and the total generated power during power interchange, and uses the power generation suppression rate setting unit 509 and the demand suppression rate notification unit 510 to determine the distribution source and distribution destination distribution lines. Adjustment is performed so that the voltage is within a predetermined voltage range. Further, when it is determined that the power to be interchanged can be reduced, the power monitoring unit 511 during power interchange returns the processing to the power interchange method calculation unit 505 to reset the power interchange route.

  Hereinafter, the operation of the power interchange method calculation means 505 performed when an accident is detected will be described.

  FIG. 3 shows the operation of the power interchange method calculation means 505.

  In step 601, the power interchange method calculation unit 505 starts operation in response to the occurrence of an accident.

  In step 602, the power interchange method calculation means 505 identifies the location of the power outage, turns off the air switches 311 and 312 before and after the power outage section, and switches the upstream of the air switches 311 and 312 in the distribution line 802. If it exists, turn it ON. In step 603, the power interchange method calculation means 505 selects a power interchange route candidate that is a candidate for a power interchange route to the power recovery section based on the information in the air switch, and creates a power interchange route candidate list 614. Then, one power interchange route is selected from the power interchange route candidates.

  FIG. 4 shows a power interchange route candidate list 614.

  The power interchange route candidate list 614 has an entry for each power interchange route candidate. The entry of a certain power interchange route candidate includes a candidate number indicating a power interchange route candidate, a switch number indicating an air switch that is closed to connect the power interchange route candidate, and a power interchange from the power system. A system reserve Y1 [MW], which is a reserve, a distributed power reserve Y2 [MW], which is a reserve for power interchange from a distributed power supply, and a total reserve Y1 + Y2 [MW] are shown. The reserve capacity with the power system or distributed power source as the supply source is obtained by subtracting the power supplied from the supply source to the power interchange route candidate from the maximum power that can be supplied from the supply source to the power interchange route candidate. This is a value that can be increased from the supply source to the power interchange route candidate. The total reserve capacity of the power interchange route candidate is an increase of the power supplied to the power interchange route candidate. This total reserve capacity can be used for electric power to be accommodated from the power interchange route candidate to the power recovery section.

  The power interchange method calculation unit 505 calculates, for each power interchange route candidate, a value obtained by subtracting the transmitted power from the maximum transmittable power obtained by the maximum transmittable power grasping unit 512 as the system reserve power Y1. The power accommodation method calculation means 505 is a value obtained by subtracting the generated power obtained by the distributed power generation power monitoring means 502 from the maximum power available power obtained by the maximum power generation available power grasping means 507 of the distributed power source for each power accommodation route candidate. Is calculated as the distributed power reserve Y2. The power interchange method calculation means 505 calculates the sum of the system reserve Y1 and the distributed power reserve Y2 as the total reserve for each power interchange route candidate.

  For example, in step 603, the power accommodation method calculation means 505 selects a power accommodation route candidate having the smallest total reserve capacity from the power accommodation route candidate list 614 as the power accommodation route, and proceeds to the next step. In step 604, the power accommodation method calculation means 505 obtains the demand power D1 of the power recovery section that is the accommodation destination from the section power database 504. Here, the power interchange method calculation means 505 assumes that the load in the power recovery section has been restored and the distributed power source in the power recovery section has not been restored, and the total power consumption in the power recovery section is calculated as the total power consumption before the power failure. And the total generated power in the power recovery section is zero. Therefore, the demand power D1 here is equal to the total power consumption in the power recovery section before the power failure. In step 605, the power accommodation method calculation means 505 reads the system reserve Y1 corresponding to the power accommodation route from the power accommodation route candidate list 614, and in step 606, reads the distributed power reserve Y2 corresponding to the power accommodation route to obtain the total reserve. The force Y1 + Y2 is calculated. In step 607, the power interchange method calculation means 505 compares the demand power D1 in the power recovery section with the total reserve capacity Y1 + Y2.

  If it is determined in step 607 that D1 <Y1 + Y2 (YES), since the power demand in the power recovery section is smaller than the total reserve capacity (supply capability) of the power interchange route, the power interchange method calculation means 505 in step 612 The power generation suppression rate of the distributed power source of the distribution line 803 of the interchange source is reset so that the voltage at each point 803 falls within a predetermined voltage range. Thereby, the power accommodation method calculation means 505 suppresses the power generation of the distributed power source of the accommodation source according to the demand power in the power recovery section. Thereafter, in step 613, the power accommodation method calculation unit 505 operates the switch according to the power accommodation route, and ends the operation. At this time, the switch operating means 508 transmits an instruction to turn ON to the air switch for power accommodation according to the power accommodation route.

  When it is determined in step 607 that D1 ≧ Y1 + Y2 (NO), since the power demand in the power recovery section is equal to or greater than the total reserve capacity of the power accommodation route, in step 608, the power accommodation method calculation unit 505 determines the power accommodation route candidate list. In 614, it is determined whether there is a power interchange route candidate having a total reserve capacity larger than that of the power interchange route. When it is determined in step 607 that there is a power interchange route candidate with a large total reserve capacity (YES), in step 609, the power interchange method calculation means 505 calculates the sum after the power interchange route among other power interchange route candidates. A power accommodation route candidate having a large reserve capacity is selected as a new power accommodation route, and the process returns to step 605. When it is determined in step 607 that there is no power accommodation route candidate with a large total reserve capacity (NO), the power accommodation method calculation unit 505 determines that the total reserve capacity cannot be increased any more, and suppresses demand. The target of demand suppression may be limited to the power recovery section of the accommodation destination or may include the distribution line of the accommodation source.

  When the demand suppression target is a power recovery section, in step 610, the power accommodation method calculation unit 505 sets the demand suppression rate R of the demand suppression target to satisfy D1 * R <Y1 + Y2, and in step 611, the demand suppression rate The notification means 510 notifies the demand suppression target consumer of a demand suppression rate or a demand suppression instruction. Priorities may be set in advance for each load or for each customer. In this case, for example, the power accommodation method calculation unit 505 selects the demand suppression target based on the demand suppression rate or the demand suppression amount, in order from the load with the highest priority until the received power becomes smaller than the total reserve capacity. Thereafter, the power interchange method calculation means 505 executes the above-described steps 612 and 613 and ends the operation.

  The customer who is notified of the demand restraint rate restrains demand. Note that the demand suppression rate notifying unit 510 may directly control the load based on a contract with a consumer.

  The above is the operation of the power interchange method calculation means 505.

  According to the operation of the power interchange method calculation means 505, this calculates the power that can be supplied to the power recovery section by the distribution source distribution line for each power interchange route candidate, and calculates the demand power in the power recovery section. Thus, it is possible to determine the power accommodation route based on the supply capacity of the accommodation source and the demand of the accommodation destination and prevent overload. In addition, when the supply capacity of the accommodation source is excessive, the supply capacity can be reduced by suppressing power generation. In addition, when the supply capacity of the accommodation source is insufficient, the demand can be reduced by suppressing the demand. In addition, the number of distribution lines that can be accommodated can be kept as small as possible while preventing overload. In order to identify a new power outage section, it is desirable to keep the distribution lines that are not necessary as an interchange source independent. Therefore, it is desirable that the number of interchangeable distribution lines is small. Further, the reserve capacity of the distribution lines other than the managed interchange source and the interchange destination can be kept to the maximum, and the reserve capacity can be used for power interchange to the power recovery section of a new accident.

  The operation of the power interchange power monitoring means 511 performed during power interchange will be described below.

  FIG. 5 shows the operation of the power monitoring means 511 during power interchange.

  In step 702, the power interchange power monitoring means 511 reads the current total power consumption of the power recovery section from the section power database 504 and calculates the demand power D1 of the power recovery section. In step 703, the power accommodation power monitoring unit 511 determines whether the total reserve capacity of the power accommodation route is the maximum value of the total reserve capacity in the power accommodation route candidate list 614.

  When it is determined in step 703 that the total reserve capacity of the power interchange route is the maximum value (YES), in step 704, the power interchange power monitoring means 511 determines whether the demand power D1 in the power recovery section and the total reserve capacity Y1 + Y2 are large or small. Make a comparison.

  If it is determined in step 704 that D1 ≧ Y1 + Y2 (NO), since the power demand in the power recovery section is equal to or greater than the total reserve capacity of the power interchange route, the power monitoring means 511 during power interchange suppresses the demand in step 705. The rate R is set so as to satisfy the condition D1 * R <Y1 + Y2, and the customer whose demand is to be suppressed is notified in step 706. If it is determined in step 704 that D1 <Y1 + Y2 (YES), since the power demand in the power recovery section is smaller than the total reserve capacity of the power interchange route, in step 707 the power interchange power monitoring means 511 displays the total reserve capacity. It is determined whether it is possible to select a power interchange route that reduces the power consumption. When it is determined in step 707 that setting is possible (YES), in step 708, the power accommodation power monitoring unit 511 newly selects a power accommodation route candidate for reducing the total reserve capacity from the power accommodation route candidate list 614. Re-select as a suitable power interchange route and return to the start. At this time, the switch operating means 508 transmits an instruction to change the state to the air switch for power accommodation in accordance with the reselected power accommodation route. When it is determined in step 707 that the setting is impossible (NO), the power interchange power monitoring unit 511 returns the process to the start. The power monitoring means 511 during power interchange operates from the start at regular intervals.

  When it is determined in step 703 that the total reserve capacity of the power interchange route is not the maximum value (NO), in step 709, the power interchange power monitoring means 511 compares the demand power D1 in the power recovery section with the total reserve capacity Y1 + Y2. I do.

  If it is determined in step 709 that D1 <Y1 + Y2 (YES), since the power demand in the power recovery section is smaller than the total reserve capacity of the power accommodation route, the power monitoring means 511 during power accommodation in step 710 determines the power accommodation route. Is determined to be the minimum value of the total reserve capacity in the power interchange route candidate list 614.

  When it is determined in step 710 that the total reserve capacity of the power accommodation route is the minimum value (YES), the power monitoring means 511 during power accommodation cannot further reduce the total reserve capacity in step 711, so The power generation suppression rate of the distributed power source in the distribution line 803 is reset, and the process is returned to the start.

  When it is determined in step 710 that the total reserve capacity of the power accommodation route is not the minimum value (YES), the power monitoring means 511 during power accommodation moves the process to step 707.

  If it is determined in step 709 that D1 ≧ Y1 + Y2 (NO), since the power demand in the power recovery section is greater than or equal to the total reserve capacity of the power interchange route, the power monitoring means 511 during power interchange in step 712 The power interchange route candidate that expands the total reserve capacity from the route candidate list 614 is reselected as a new power interchange route, and the process is returned to the start. At this time, the switch operating means 508 transmits an instruction to change the state to the air switch for power accommodation according to the reselected power accommodation route.

  When it is detected that the power failure section has been restored, the power interchange power monitoring means 511 terminates the operation, and the switch operating means 508 turns on the air switches 311 and 312 to turn the power failure section and power recovery section on. Connect and terminate power interchange.

  According to the operation of the power interchange means 511 described above, when the distributed power source is restored after the start of the power interchange during the power interchange, or when the generated power of the distributed power source changes as in solar power generation. Even if it exists, according to the change of the generated electric power of a distributed power supply, an electric power interchange route, a power generation suppression rate, and a demand suppression rate can be changed.

  Hereinafter, the relationship between power accommodation, demand restraint, and power generation restraint determined by the power accommodation method calculating means 505 and the power interchange during power monitoring means 511 will be described.

  FIG. 6 shows the relationship between power interchange, demand suppression, and power generation suppression.

  Each row in this figure indicates a combination of a demand suppression rate determined by the power interchange method calculation unit 505 and the power interchange in-progress power monitoring unit 511, the total reserve capacity of power interchange route candidates, and the power generation suppression rate. As the line goes up, the power shortage, which is a value (D1− (Y1 + Y2)) obtained by subtracting the total reserve capacity of the power interchange route from the power demand in the power recovery section, is larger. Here, it is assumed that five power interchange route candidates are determined, and total reserve powers of five levels of maximum, large, medium, small, and minimum are respectively calculated. Assume that four levels of values of large, medium, small, and none are set as the demand suppression rate. Assume that four levels of values of large, medium, small, and none are set as the power generation suppression rate.

  When the power demand in the power recovery section is larger than the maximum total reserve capacity among the power interchange route candidates, the distribution system monitoring and control device 500 selects the power interchange route having the maximum total reserve capacity from the power interchange route candidates. In addition to power interchange, demand is suppressed according to the difference between the demand power in the power recovery section and the total reserve capacity of the power interchange route, and power generation is not suppressed. In this case, the power shortage becomes positive, and the power distribution monitoring and control device 500 increases the demand suppression rate as the power shortage increases.

  When the power demand in the power recovery section is smaller than the maximum total reserve capacity in the power interchange route candidate and the power demand in the power recovery section is greater than the minimum total reserve capacity in the power interchange route candidate, the distribution system monitoring control The device 500 selects a power accommodation route according to the demand power in the power recovery section, performs power accommodation, and does not perform demand suppression and power generation suppression. In this case, the power distribution system monitoring and control apparatus 500 selects a power accommodation route having a minimum total reserve capacity that is equal to or greater than the power demand in the power recovery section, from among the power accommodation route candidates.

  When the power demand in the power recovery section is smaller than the minimum total reserve capacity in the power interchange route candidates, the distribution system monitoring and control device 500 selects the power interchange route having the minimum total reserve capacity from the power interchange route candidates. In addition to power accommodation, power generation is suppressed according to the difference between the total reserve capacity of the power accommodation route and the demand power in the power recovery section, and demand is not suppressed. In this case, the power shortage becomes negative, and the power distribution suppression monitoring device 500 increases the power generation suppression rate as the power shortage decreases.

  Hereinafter, the maximum power generation possible power grasping means 507 will be described.

  Most of the current solar power generation devices generate electricity with maximum power and perform reverse power flow in the system. In the future, when a large number of solar power generation devices are widely used in the distribution system, it is assumed that the generated power of the solar power generation device is suppressed for the purpose of system protection. It is generally difficult to know the maximum power that can be generated (= maximum power that can be generated) during power generation suppression operation. Hereinafter, some specific examples for grasping the maximum power that can be generated by the distributed power source will be described.

  FIG. 7 shows a first specific example of the maximum power generation possible power grasping means 507.

  Here, a case where the distributed power source 900 is a solar power generation device will be described. In the first specific example, the distributed power source 900 includes a photovoltaic power generation panel 901, a PCS 902 that controls the photovoltaic power generation panel 901 and power conversion, a communication device 903 connected to the communication network 800, a distribution system, and a distributed system. And a power meter 904 that indicates power transmitted and received between the power sources 900. The communication device 903 transmits the generated power of the distributed power source measured by the power meter and the maximum power that can be generated by the distributed power source calculated by the PCS 902 to the distribution system monitoring control device 500. In the distribution system monitoring and control apparatus 500, the distributed power generation power monitoring means 502 receives the generated power from each distributed power supply 900, and the maximum power generation possible power grasping means 507 receives the maximum power generation possible power from each distributed power supply 900.

  The distributed power supply 900 may further include a solar radiation meter 906 and an EMS (Energy Management System) 905 connected to the solar radiation meter 906 and the communication device 903. In this case, the EMS 905 calculates the maximum power that can be generated based on the amount of solar radiation.

  The distributed power supply 900 may include a computing device 907 connected between the PCS 902 and the communication device 903. In this case, the calculation device 907 calculates the maximum power that can be generated.

  FIG. 8 shows a second specific example of the maximum power generation possible power grasping means 507.

  In the second specific example, the distributed power supply 900 includes a solar power generation panel 901, a PCS 902, and a communication device 903. The communication device 903 transmits the operating voltage and current of the PCS 902, the panel temperature of the photovoltaic power generation panel 901, and the like to the distribution system monitoring control device 500. The distribution system monitoring and control device 500 calculates the maximum power that can be generated based on the operating voltage, current, and panel temperature.

  The relationship between the amount of solar radiation and the maximum power that can be generated is determined in advance for each panel temperature. The greater the amount of solar radiation, the greater the maximum power that can be generated. Also, the lower the panel temperature, the greater the maximum power that can be generated.

  In addition, for each amount of solar radiation, the relationship between the operating voltage applied to the photovoltaic power generation panel 901 by the PCS 902 and the current flowing through the photovoltaic power generation panel 901 is determined in advance. According to this relationship, the generated power is maximized at a specific operating voltage. The generated power can be changed by setting the generated power at this time as the maximum power that can be generated and changing the operating voltage of the PCS 902 according to the power generation suppression rate.

  Therefore, the maximum power generation possible power grasping means 507 can calculate the maximum power generation possible power and the generated power from the operating voltage, current, and panel temperature.

  FIG. 9 shows a third specific example of the maximum power generation possible power grasping means 507.

  In the third specific example, a communication device 913 connected to the communication network 800 and a solar radiation meter 916 are provided in each area under the management of the distribution system monitoring control device 500. The communication device 913 transmits information on the amount of solar radiation measured by the solar radiation meter 916 to the distribution system monitoring control device 500. The maximum power generation possible power grasping means 507 of the distribution system monitoring control device 500 calculates the maximum power generation possible power of each area based on the received information on the amount of solar radiation.

  According to the operation of the first case, even when a large number of photovoltaic power generation devices are widely used, the power distribution system monitoring and control device 500 does not cause an overload after a power failure and inconveniences a specific consumer. Without power recovery.

  Hereinafter, two cases will be described as specific examples of the operation of the distribution system monitoring and control apparatus 500.

  As a first case, it is assumed that a short circuit 801 occurs between the distribution line 802 and the pole transformer 321 and the distribution line 802 is out of power. Since the distribution system monitoring and control device 500 turns off all the air switches 311, 312, 313, and 314 on the distribution line 802 and turns on the air switches 311, the power switch is again turned on. The section between 311 and 312 is specified as the power outage section. The distribution system monitoring control device 500 turns off the air switch 311 again. In this state, in the distribution line 802, the section between the air switches 312 and 314 other than the power outage section remains blacked out, so the distribution system monitoring and control device 500 sets this section as the power recovery section. The distribution system monitoring and control device 500 keeps the air switch 312 immediately downstream of the power outage section OFF, turns on the air switches 313 and 314 downstream of the air switch 312 and turns on the air switches 352 for power interchange, By turning ON 353, power is accommodated from the distribution source distribution lines 803 and 804 to the power return section of the distribution destination distribution line 802, as indicated by the dashed arrows in FIG.

  FIG. 10 shows a timing chart of the first case.

  This figure shows the demand power in the power recovery section, the power generation suppression rate of the solar power generation devices 101, 102, 104, 105, 106, and the air switches 311, 312, 313, 314, 314, 352, 353, respectively. The time change with ON / OFF state is shown.

  The period from time 0 to t1 represents a normal time. The total power consumption of the loads 201, 202, and 203, which are loads in the power recovery section at this time, is P1. The power demand P2 in the power recovery section is a value obtained by subtracting the total generated power G1 of the photovoltaic power generation apparatuses 101, 102, and 103 in the power recovery section from P1, and is supplied from the distribution substation 302 via the distribution line 802. This is the power received by the power recovery section. The power demand in the power recovery section is measured by the measured values in the air switches 312 and 314. At this time, the power generation suppression rates of the solar power generation apparatuses 101, 102, and 103 are set to 50%.

  When the short circuit 801 occurs at time t1, the power distribution system monitoring and control device 500 identifies the power outage section, and selects the power interchange route and calculates the relaxation amount of the power generation suppression rate at the interchange source. At this time, since the distributed power supply in the power recovery section has not been restored, the demand power P1 in the power recovery section is equal to the power consumption P1 before the power failure. It is assumed that a power interchange route from the distribution lines 803 and 804 to the distribution line 802 is selected. In this case, the power generation suppression rate of the photovoltaic power generation apparatuses 104, 105, and 106 of the distribution line 803 serving as the accommodation source is reduced.

  At time t <b> 2, the distribution system monitoring and control device 500 determines a power accommodation route based on the information of each distribution line, and turns on the air switches 313, 314, 352, and 353 according to the decided power accommodation route. Thus, power is supplied again to the power recovery section by power interchange from the distribution lines 803 and 804 (power recovery). The distribution system monitoring and control apparatus 500 sets a route from the distribution lines 803 and 804 to the distribution line 802 as a power interchange route candidate, calculates the total reserve capacity of the power interchange route candidate, and the total reserve capacity is larger than the demand power in the power recovery section. A power interchange route candidate is selected as a power interchange route. Here, the power interchange route from the distribution lines 803 and 804 to the power recovery section is selected. Since the demand for the distribution line 803 from the distribution substation 303 is increased due to the start of the power interchange, the distribution system monitoring and control device 500 is connected to the distribution line 803 by the photovoltaic power generation apparatuses 104, 105, and 106. The generated power is increased by relaxing (decreasing) the power generation suppression rate. In this case, the power generation suppression rate is relaxed from 50% to 0% (no suppression).

  At time t3, the small photovoltaic power generators 102 and 103 automatically recover, and the power generation in the power recovery section increases, so that the power demand in the power recovery section decreases. At this time, the distribution system monitoring and control device 500 obtains the power generation suppression rate of the solar power generation devices 104, 105, and 106 so that the voltage downstream of the distribution line 803 does not deviate from the predetermined voltage range. In this case, the distribution system monitoring and control device 500 gradually increases the power generation suppression rate of the solar power generation devices 104, 105, and 106 to 10% and 20% in response to the return of the solar power generation devices 102 and 103. Go. Here, the distribution system monitoring and control device 500 also adjusts the power generation suppression rate of the solar power generation devices 102 and 103 to the solar power generation devices 104, 105, and 106.

  When the large-scale photovoltaic power generation apparatus 101 returns at time t4, the power demand in the power recovery section is greatly reduced. The distribution system monitoring and control apparatus 500 calculates the total reserve capacity of power interchange route candidates from the distribution line 803 to the distribution line 802 that do not use the distribution line 804. When the power demand in the power recovery section falls below the total reserve capacity of this power interchange route candidate, the distribution system monitoring and control device 500 selects this power interchange route candidate as the power interchange route and turns off the air switch 353. By doing so, the power interchange from the distribution line 804 to the distribution line 802 is stopped, and only the power interchange from the distribution line 803 to the distribution line 802 is continued. At this time, the power distribution system monitoring and control apparatus 500 generates power from the solar power generation apparatuses 101, 102, 103, 104, 105, and 106 so that the voltage at each place in the distribution line 803 that is the source of the supply does not deviate from a predetermined voltage range. Find the inhibition rate. In this case, the power distribution system monitoring control device 500 maintains these power generation suppression rates at 20%.

  When power is interchanged from the distribution lines 803 and 804 to the distribution line 802, or when power is interchanged from the distribution line 804 to the distribution line 803, the distribution system monitoring and control device 500 turns on the air switch 356 for power interchange. Anyway. In the case where power is passed from the distribution line 804 to the distribution line 802 and power is not passed from the distribution line 803 to the distribution line 802, the distribution system monitoring and control device 500 turns on the air switch 355 for power accommodation. good. In the distribution line 802, when there is a power outage section upstream of the air switch 311, the power distribution system monitoring and control device 500 may turn on the air switch 351 for power interchange.

  According to the operation of the first case described above, when a short circuit 801 occurs in the distribution line 802, power is exchanged from the distribution lines 803 and 804 of the interchange source to the return section of the interchange destination. While preventing the load state, the time from power failure to power recovery in the power recovery section can be shortened.

  The second case is a case where a short circuit 801 similar to the first case occurs and the power consumption in the power recovery section before the power failure is larger than the first case. The distribution system monitoring and control device 500 turns on the air switches 352, 353, and 354 for power interchange when power is restored, and performs power interchange from the distribution lines 803 and 804 and an external distribution line to the distribution line 802.

  FIG. 11 shows a timing chart of the second case.

  The process is the same as in the first case until time t2.

  Even if the air switches 313, 314, 352, 353, and 354 are turned on at time t2, the demand power in the power recovery section exceeds the total reserve capacity of the power interchange route, and thus demand suppression is required. In this case, areas 402 and 403 that are power recovery sections are targeted for demand suppression, but the entire section (accommodation source and accommodation destination) related to the power accommodation route may be targeted for suppression. Since the power demand in the power recovery section is zero when a power failure occurs, the demand suppression rate is expressed as 100%. At time t2, the distribution system monitoring control device 500 sets the demand suppression rate in the power recovery section to 50% to prevent overload. The distribution system monitoring and control device 500 stores the priority set by the customer for each load under management. The distribution system monitoring and control device 500 selects loads as demand suppression targets in descending order of priority until the demand suppression rate is satisfied. The power distribution system monitoring and control apparatus 500 may directly control the demand suppression target to reduce the power consumption of the demand suppression target. Moreover, the power distribution system monitoring and control apparatus 500 may notify the consumer of the demand suppression target notification, and the consumer may set the suppression rate of the demand suppression target according to the notification.

  At time t3, the small photovoltaic power generators 102 and 103 automatically return, and the generated power in the power recovery section increases. Along with this, the distribution system monitoring and control device 500 reduces the demand suppression rate in the power recovery section.

  When the large-scale photovoltaic power generation apparatus 101 returns at time t4, the power demand in the power recovery section is greatly reduced. When the power demand in the power recovery section falls below the total reserve capacity of the power interchange route candidates from the distribution line 803 to the distribution line 802, the distribution system monitoring and control device 500 turns off the air switch 354 to The power interchange from the distribution line to the distribution line 802 is stopped via the air switch 354, and only the power interchange from the distribution line 803 to the distribution line 802 is continued. At this time, the power distribution system monitoring and control apparatus 500 generates power from the solar power generation apparatuses 101, 102, 103, 104, 105, and 106 so that the voltage at each place in the distribution line 803 that is the source of the supply does not deviate from a predetermined voltage range. Find the inhibition rate. In this case, the distribution system monitoring control device 500 sets these power generation suppression rates to 10%.

  According to the operation of the second case described above, power can be restored after a power failure without causing an overload and minimizing the inconvenience of consumers.

  The present invention is not limited to the above embodiments, and can be modified in various other forms without departing from the spirit of the present invention.

101, 102, 103, 104, 105 ... Solar power generation devices 111, 112 ... Power receiving cubicles 201, 202, 203, 204 ... Loads 301 ... Substations 302, 303, 304 ... Distribution substations 311, 312, 313 ... Air Middle switch 321, 322, 323 ... pole transformer 351, 352, 353, 354, 355, 356 ... air switch 500 ... distribution system monitoring and control device 800 ... communication network 802, 803, 804 ... distribution line

Claims (6)

Each of the plurality of distribution lines is connected to an electric power system, and an interchangeable switch that is normally opened is provided between the plurality of distribution lines, and each of the plurality of distribution lines is normally connected. A system monitoring and control device that includes a plurality of sections that can be divided by a plurality of distribution switches that are charged, and that monitors and controls the plurality of distribution lines,
A communication unit that receives power consumption of a load connected to a section in the plurality of distribution lines, and generated power of a distributed power source connected to a section in the plurality of distribution lines,
When an accident in the plurality of distribution lines is detected, a calculation unit that identifies the section in which the accident has occurred as an accident section, and selects a section other than the accident section as a power recovery section in the distribution line including the accident section When,
With
The communication unit disconnects between the accident section and the power recovery section by transmitting an opening instruction to a switch for distribution between the accident section and the power recovery section,
The arithmetic unit includes an accommodation switch including an accommodation switch between a distribution line other than the specific distribution line and the power recovery section in the plurality of distribution lines based on information of the plurality of accommodation switches. A plurality of accommodation route candidates that are route candidates are determined, and a reserve capacity that is an increase in power supplied to the accommodation route candidate is calculated for each accommodation route candidate of the plurality of accommodation route candidates. Calculating the total power consumption of the load in the power recovery section before the accident as demand power, and selecting an accommodation path candidate having reserve capacity larger than the demand power as the accommodation path among the plurality of accommodation path candidates And
The communication unit transmits power from the accommodation path to the power recovery section by transmitting an input instruction to the accommodation switch included in the accommodation path.
System monitoring and control device. During the accommodation, the calculation unit calculates, as the demand power, a value obtained by subtracting the total generated power of the distributed power sources in the power recovery section from the total power consumption of the load in the power recovery section, However, when it is determined that the reserve capacity of the accommodation path is smaller than the demand power and there is a first accommodation path candidate having a reserve capacity larger than the demand power among the plurality of accommodation path candidates, the calculation unit Changes the first accommodation path candidate as the accommodation path, and the communication unit transmits an instruction to the accommodation switch related to the change of the accommodation path to the power recovery section using the accommodation path. To accommodate power,
The system monitoring control apparatus according to claim 1. During the accommodation, when the calculation unit determines that there is a second accommodation path candidate having a reserve capacity smaller than the reserve capacity of the accommodation path and larger than the demand power among the plurality of accommodation path candidates, the calculation The unit changes the second accommodation route candidate as the accommodation route, and the communication unit transmits an instruction to the accommodation switch related to the change of the accommodation route to the power recovery section using the accommodation route. To accommodate power,
The system monitoring control apparatus according to claim 2. During the accommodation, when the computing unit determines that the accommodation route has a minimum reserve power among the plurality of accommodation route candidates, the computing unit may be placed in either the power recovery section or the accommodation route. Select a target distributed power source from among the connected distributed power sources, calculate a control value indicating the generated power of the target distributed power source required according to the reserve capacity of the accommodation path and the demand power, the communication unit , By reducing the generated power of the target distributed power supply by transmitting an instruction including the control value to the target distributed power supply,
The system monitoring control apparatus according to claim 3. When the calculation unit determines that the reserve capacity of the accommodation path is smaller than the demand power and the accommodation path has the maximum reserve capacity among the plurality of accommodation path candidates, the calculation section The load that is connected to either the power recovery section or the accommodation path is calculated based on the demand restriction amount so that the power is less than the reserve capacity of the accommodation path. The target load is selected from the above, and the communication unit reduces the demand power by transmitting an instruction indicating demand suppression to the customer facility having the target load.
During the accommodation, when the arithmetic unit determines that the reserve capacity of the accommodation path is larger than the demand power, the communication unit transmits an instruction to release the demand suppression to the customer facility having the target load. To
The system monitoring control apparatus according to claim 4. The calculation unit supplies, to each of the plurality of accommodation path candidates, transmission power that is power supplied from the power system to the accommodation path candidates, and supply from the power system to the accommodation path candidates. Obtaining the maximum transmittable power, which is the maximum possible power, calculating a value obtained by subtracting the transmitted power from the maximum transmittable power as the system reserve, and supplying it from the flexible source distributed power source to the flexible route candidate The generated power that is the generated power and the maximum power that can be generated that is the maximum power that can be supplied from the accommodation source distributed power source to the accommodation path candidate, and the generated power is subtracted from the maximum power that can be generated A value is calculated as the distributed power reserve, and the sum of the system reserve and the distributed power reserve is calculated as the reserve.
The system monitoring control apparatus according to any one of claims 1 to 5.

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