JP2009071889A - Operation management method for distribution system, system, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To carry out cooperation control between voltage rationalization control with a voltage control apparatus set on the high voltage system side of a distribution system and voltage-rise suppression control with a distributed power supply linked to the low voltage system side of the distribution system. <P>SOLUTION: A centralized control target voltage, as the upper limit value of the voltage rationalization control with the voltage control apparatus such as a loop controller or the like, is so set as to be a value between the control start voltage of the distributed power supply and the control release voltage. Then, the voltage-rise suppression control with the distributed power supply is started, allowing the voltage control apparatus such as the loop controller or the like to continue voltage rationalization control, in a condition that the voltage-rise suppression control is not released. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a distribution system operation management method, system, and program. More specifically, the present invention relates to an operation management method, system, and program suitable for voltage control in a distribution system in which a distributed power source is connected to the low voltage system side and a voltage control device such as a loop controller is installed on the high voltage system side.

  In recent years, there is a concern about the influence on the distribution system in a situation where the connection to the system of the distributed power source is progressing. In order to cope with this, when a distributed power source is grid-connected, measures are taken in accordance with the “system grid technical regulations” (Non-patent Document 1). The countermeasure to suppress the voltage increase of the conventional distribution system according to the “system interconnection technical regulations” is that the distributed power source itself first controls the phase advance reactive power, and if this does not provide a sufficient suppression effect, the output is effective. The power is reduced.

  Furthermore, as a method of controlling such a distributed power source, an upper limit value of an appropriate voltage is set, and when the detected voltage exceeds the upper limit value, the driving power factor is decreased to advance the phase reactive power. Has been proposed to increase the power generation output and the operating power factor to recover the phase-advanced power when the voltage rise is suppressed by a large amount and the output voltage is greatly below the upper limit. Non-patent document 2).

  On the other hand, a power electronics device called a loop controller (LPC) is installed at a normally open point of an existing dendritic power distribution system, and a configuration of a demand point system that enables loop mesh operation is used to concentrate the high voltage system. Research is being conducted to increase the amount of distributed power sources that could be limited by controlling the side voltage.

  The loop controller is an AC / DC converter (BTB system) applied to a semiconductor power conversion technology that is DC-linked as shown in FIG. 10. One of the three-phase AC is once converted into DC by a transformer and an AC / DC converter, Again, it is returned to AC by the orthogonal transformer and transformer, and output from the other, and the current flowing through the loop controller and the active power and reactive power of each line are controlled arbitrarily by the control of the AC / DC converter and the orthogonal transformer. Is possible. According to this loop controller, not only between distribution lines of the same distribution substation transformer, but also between distribution lines of different distribution substation transformers with different phases and voltages, between distribution lines of different distribution substation transformers It is also possible to make a loop. In addition, power control between looped lines and voltage control at both ends by controlling reactive power can be achieved at the same time. In the event of a distribution line fault, the characteristics of the AC / DC converter can be used to prevent the passage of fault current. Is something that can be made possible.

  For operation management in the demand area system using this loop controller, the operation management system in the demand area system collects each information in the system, and the optimal control amount of the active power and reactive power of the loop controller is determined by calculation. A system for controlling each device in a system including a loop controller has been proposed (Non-Patent Document 3). In the demand system, detailed voltage management is possible by monitoring the voltage and current at each point with a switch with sensor and operation program, and enabling voltage control by local reactive power injection by the loop controller. To do. In this case, voltage management by pole transformer taps is not performed, but management is performed by control of transformer substation taps and loop control, so it is possible to manage by managing the voltage on the high voltage side with a certain tolerance. .

  In this specification, the term “centralized control” means that a specific device in the system centrally collects information in the system, and causes the device to calculate control values of other devices in the system. This means a control method that controls the entire system. The “control start voltage” is the voltage value at which the distributed power supply starts the voltage rise suppression control, and the “voltage release voltage” is the voltage rise suppression control. It means the voltage value to be released. Furthermore, “hysteresis-like control” is a control method in which the voltage at the connection point is monitored by a distributed power source as in Non-Patent Document 2, and the voltage value at which voltage rise suppression control is started is different from the voltage value to be released. Means.

"Rules for grid interconnection" NEC Association Grid interconnection specialist group (JEAC 9701-2006), 2006 Takashi Ishikawa, Kosuke Kurokawa et al. “Evaluation of operating characteristics when multiple photovoltaic power generation systems are linked” Proceedings of the IEEJ New Energy and Environment Study Group (2001/02/21) Satoshi Uemura, Katsuhiro Matsuda: “Proposal of operation management method for demand system-Development of optimal control amount determination program”, Central Research Institute of Electric Power, Research report, T01059, 2001

  However, even though the distributed power supply itself has a voltage rise suppression function, it is not possible to optimize the voltage of the entire system, and when the distributed power supply is connected in large quantities or distribution lines If the power distribution system is biased, the voltage management of the distribution line becomes difficult, and there is a problem that the amount of connection is limited, that is, the amount of introduction of the distributed power source is limited, or the connection point is due to their reverse power flow. In some distributed power sources, there is a possibility that the power generation output is reduced, and in some cases, the operation may be continued at a low output.

  On the other hand, although these problems can be solved by installing a voltage control device such as a loop controller on the high voltage system side to make a demand area system in which the dendritic distribution line is looped, the loop controller etc. If voltage control is to be performed using only the voltage control device, there is a problem that the required capacity of the loop controller and the like increases and the cost increases. In addition, at present, voltage optimization is performed by the voltage rise suppression function provided in the distributed power supply. Therefore, the voltage fluctuation of the entire system can be optimized only by taking measures on the high voltage side, ignoring this. Implementing is not the best measure.

  Accordingly, the present invention provides an operation management method, system, and program for a distribution system that can reduce the capacity of a voltage control device such as a loop controller by controlling the above two controls in a coordinated manner. With the goal.

  In order to achieve this object, the operation management method for the distribution system according to claim 1 is a distribution system in which a distributed power source is connected to the low voltage system side and a voltage control device is installed on the high voltage system side. The operation management system that performs centralized control has a control start voltage that is a voltage value at which the distributed power source starts voltage rise suppression control, and a voltage value that is equal to or lower than the control start voltage and at which the distributed power source cancels the voltage rise suppression control. The voltage value between a certain control release voltage is the centralized control target voltage that is the upper limit value of the voltage optimization control by the voltage control device, and the voltage control device outputs the centralized control target voltage to suppress the voltage in the distribution system. The amount of reactive power output is controlled.

  Therefore, the voltage optimization control by the voltage control device is continued in a state where the voltage rise suppression control by the distributed power source is started and not released.

  The operation management method for the distribution system according to claim 2 is an operation management for centralized control of the distribution system in a distribution system in which a distributed power source is connected to the low voltage system side and a voltage control device is installed on the high voltage system side. The system receives the power generation amount of the distributed power source and the measured value of the load amount of all consumers as customer information from the supply and demand interface, and demands the centralized control target voltage, which is the upper limit value of voltage optimization control of voltage control equipment, as demand. The voltage at which the distributed power supply cancels the voltage rise suppression control when the power flow is calculated based on the house information and the voltage is below the control start voltage and the control start voltage, which is the voltage value at which the distributed power supply starts the voltage rise suppression control. It is calculated as a value between the control release voltage, which is a value, and the output amount of reactive power from the voltage control device is controlled so as to suppress the voltage in the distribution system to the central control target voltage.

  According to a third aspect of the present invention, in the operation management method for the distribution system according to the first aspect, the central control target voltage is approximated to the control release voltage. Therefore, the voltage optimization control by the voltage control device is performed at a low voltage value that is closer to the control release voltage.

  According to a fourth aspect of the present invention, in the operation management method for a power distribution system according to any one of the first to third aspects, the voltage control device is a loop controller, and the central control target voltage is included in the power distribution system. The output amounts of active power and reactive power from the loop controller are transmitted to the control device of the loop controller so as to suppress the voltage.

  The power distribution system operation management system according to claim 5 is an operation management system in which a distributed power source is connected to the low voltage system side, a voltage control device is installed on the high voltage system side, and centralized control in the system is performed. And a distribution system in which the supply and demand interface is connected via a communication network, the operation management system receives customer power information from the supply and demand interface and the measured values of the loads of all consumers as customer information. And the centralized control target voltage, which is the upper limit of voltage optimization control of the voltage control device, calculates the power flow based on the customer information, and the distributed power source previously stored in the storage device performs the voltage rise suppression control. Control start voltage that is a voltage value to be started and control release voltage that is equal to or less than the control start voltage and is a voltage value at which the distributed power source cancels the voltage rise suppression control. A control amount determining means for calculating an output amount of reactive power from the voltage control device for suppressing the voltage in the distribution system to a central control target voltage, and the output amount as a voltage control device or Control amount transmission means for transmitting to the control device of the voltage control device.

  According to a sixth aspect of the present invention, in the power distribution system operation management system according to the fifth aspect of the present invention, the voltage control device is a loop controller, and the control amount determining means is connected to the central control target voltage within the distribution system. The output amounts of the active power and reactive power from the loop controller are calculated so as to suppress the voltage.

  The power distribution system operation management program according to claim 7 is an operation management system in which a distributed power source is connected to the low voltage system side, a voltage control device is installed on the high voltage system side, and centralized control in the system is performed. In a distribution system in which the supply and demand interface is connected through a communication network, the operation management system receives the measured value of the power generation amount of the distributed power source and the load amount of all customers as the customer information from the supply and demand interface. The centralized control target voltage, which is the upper limit value of voltage optimization control for voltage control equipment, is calculated based on customer information, and the distributed power source stored in advance in the storage device starts voltage rise suppression control. Control release that is equal to or lower than the control start voltage and control solution start voltage that are voltage values that the distributed power supply releases voltage rise suppression control Control amount determination processing for calculating the amount of reactive power output of the voltage control device for causing the central control target voltage to suppress the voltage in the distribution system and the output amount to be the voltage control device or voltage Control amount transmission processing to be transmitted to the control device of the control device is executed.

  Therefore, the centralized control target voltage, which is the upper limit value of the voltage optimization control by the voltage control device, is a value between the control start voltage and the control release voltage of the distributed power source in consideration of the power generation situation of the consumer. By setting so, voltage increase suppression control by the distributed power source is started, and voltage optimization control by the voltage control device is continued in a state where it is not released.

  According to the operation management method, system, and program of the power distribution system according to the present invention, since voltage rise suppression control by the distributed power source is started and not released, voltage optimization control by the voltage control device is continued. The voltage suppression function of the distributed power supply can be utilized, so that the required capacity of voltage control equipment such as a loop controller can be reduced, and the power equipment cost can be reduced. In addition, centralized management on the high-voltage distribution side facilitates voltage management of distribution lines when distributed power sources are connected in large quantities or are biased and connected to distribution lines, and does not limit the amount of connection. .

  Moreover, since the power generation amount of the distributed power source, which has been limited in the past, can be increased, the effective use of energy can be promoted.

  In addition, according to the operation management method for the power distribution system according to the third aspect, it is possible to further reduce the required capacity of the voltage control device such as the loop controller.

  Hereinafter, the configuration of the present invention will be described in detail based on embodiments shown in the drawings.

  FIG. 1 schematically shows an embodiment of a demand point system to which an operation management method and system of a power distribution system of the present invention using a loop controller is applied. Since the system configuration and the function of the entire operation management of the demand point system are publicly known, detailed description thereof will be omitted (Reference 1: Non-Patent Document 3, Reference 2: Satoshi Uemura, Katsuhiro Matsuda “ Examination of operation management method of demand area system-control effect of demand area system component equipment "Central Research Institute of Electric Power, research report T02037).

  In the demand area system according to the present embodiment, a distributed power source is connected to the low-voltage system side, and a loop controller 2 is installed at a normally open point of the dendritic distribution system on the high-voltage system side, enabling loop mesh operation. An operation management system 1 that performs centralized control in the system, a loop controller (hereinafter also referred to as LPC) 2, an operation management subsystem 3 and a supply and demand interface (hereinafter referred to as supply and demand IF. Not shown in FIG. 1) 11, which is indicated by reference numeral 4 in FIG. 11) through the communication network 12. Moreover, as control object apparatus, there exist a division switch, the transformer 5 of a substation, the circuit breaker 6, etc., for example. Further, as shown in FIG. 10, each loop controller 2 includes a loop controller terminal (not shown in FIG. 1 but indicated by reference numeral 11 in FIG. 10) as a loop controller control device. The loop controller 2 is controlled via the terminal. Of course, the loop controller terminal only needs to include a means for causing the loop controller 2 to output the control amount calculated by the control amount determination means 21, for example, the operation management system 1 or the operation management subsystem 3 includes the means. Alternatively, the means may be provided in the loop controller 2 itself.

  Here, the operation management system 1 relays information between the host system and the supply and demand IF, while exchanging information such as consignment status information between operation management systems of other demand point systems, It controls the power flow and voltage in the demand area system, and performs recovery control in the event of an accident. In this embodiment, the voltage control by the operation management system 1 performs the power flow calculation using the power generation amount of the distributed power source and the load amount of the customer as input values during normal operation, and the effective power necessary for the installation point of each supply and demand IF This is realized by creating reactive power (hereinafter referred to as system information), setting a centralized control target voltage instructing each LPC 2, determining a control output of LPC 2 based on this value, and transmitting it to each LPC terminal. The

  The operation management system 1 is realized, for example, by causing a computer 30 (computer) to execute an operation management program for the distribution system illustrated in FIG. The operation management program is input with the configuration of the distribution system to be managed, for example, the impedance of the line, the connection status, the connection position of the customer, the installation position of the LPC, etc. before starting the operation. Is stored in the storage device. The operation management program first performs customer information acquisition processing (S1). In this process, the operation management system 1 receives customer information from the supply and demand IF at every collection interval, and stores it in the storage device 33. Next, a control amount determination process (S2) is performed. In this process, the system information, the control start voltage, the control release voltage, and the customer information stored in the preprocess are stored in advance in the auxiliary storage device 33, the central control target voltage of the LPC 2 is determined by power flow calculation, and The control amount of the LPC 2 is determined so that the voltage at the point becomes the central control target voltage, and is stored in the storage device 33. Further, a control amount comparison process (S3) is performed. In this process, the control amount calculated in the control amount determination process (S2) and the predicted control amount information calculated in advance in the “operation plan” stored in advance in the auxiliary storage device 33 are read and compared. If not (S3; No), the process proceeds to a control amount transmission process (S4), and the calculated control amount is transmitted to the loop controller terminal. The loop controller controls the output to be constant according to the command value sent. This operation is performed at regular intervals, and the voltage is always optimized. On the other hand, when the calculated control amount matches the predicted control amount stored in advance (S3; Yes), the voltage optimization control only needs to be performed based on the predicted control amount information. It does not perform quantity transmission processing (S4) and waits until the next customer information acquisition. The control amount comparison process in step 3 may be omitted in some cases, and the loop controller may be controlled by the control amount calculated each time.

  In order to determine whether or not they match, a threshold value is set in advance, and if there is a change greater than or equal to the threshold value, it may be determined that they match, and if not, it may be determined that they do not match. The threshold may be set as appropriate by the system administrator according to the purpose of system control.

  As shown in FIG. 2, for example, the computer 30 (computer) executes the customer information acquisition process (S1) for receiving customer information from the supply and demand IF by executing the above distribution system operation management program. The central control target voltage of the loop controller 2 is determined based on the information acquisition means 20, the received customer information and the pre-stored control start voltage and control release voltage of the distributed power source, and the voltage at each point Control amount determination means 21 for executing a control amount determination process (S2) for determining a control amount (referred to as an output amount of active power / reactive power) of the loop controller 2 so that becomes a centralized control target voltage, and control amount determination A control amount comparison means 22 for executing a control amount comparison process (S3) for comparing the control amount calculated in the means 21 with the predicted control amount information stored in advance; Operation management system 1 the calculated control amount comprises at least a control amount transmitting means 23 for performing control amount of transmission processing for transmission to the loop controller terminal (S4) in means 21 is realized.

  Then, the operation management system 1 receives, as customer information, the power generation amount of the distributed power source 8 and the actual load values of all the consumers from the supply and demand interface, and the concentration that is the upper limit value of the voltage optimization control of the loop controller 2 The control target voltage is calculated based on the customer information and the power flow is calculated, and the distributed power source is below the control start voltage and the control start voltage at which the distributed power source starts the voltage rise suppression control, and the distributed power source releases the voltage rise suppression control. It calculates as a value between the control release voltage, calculates the output amount of active power and reactive power from the loop controller 2 for suppressing the voltage in the distribution system to the central control target voltage, and outputs the output amount to the loop controller 2 To the control device. In the tidal current calculation, it can be understood from the information of each point and the distribution system configuration information how much the loop controller 2 gives active power and reactive power, and how much the voltage at each point becomes. The output of the loop controller 2 can be determined so as to be the target voltage.

  On the other hand, the operation management subsystem 3 is a device that monitors the section in which the distribution lines are divided into several parts, and performs information monitoring and control of the switch, recovery processing in the event of an accident, and the like. The supply and demand IF is a device that monitors and controls each customer or a group of customers that are a group of several customers. Reference numeral 7 is a line switch, reference numeral 8 is a distributed power source using an inverter such as photovoltaic power generation, reference numeral 9 is a load that consumes electric power in a consumer, reference numeral 10 is a rotating machine type dispersion such as cogeneration, wind power, etc. Each power source is shown.

  As shown in FIG. 3, for example, the computer 30 for realizing the operation management system 1 includes a central processing unit (CPU) 31, a main storage device (memory) 32 such as a RAM, an auxiliary storage device 33 such as a hard disk, and a keyboard. An input device 34 such as a mouse, an output device 35 such as a display or a printer, a data reader 36 such as a disk drive for reading data recorded on a medium such as an FD, CD, or DVD, or a communication interface for communicating with the outside Hardware resources such as 37 are connected by a bus 38. The main storage device 32 and the auxiliary storage device 33 are also simply referred to as a storage device.

  The auxiliary storage device 33 stores a distribution system operation management program 39 according to the present invention. When the program is executed on the computer 30, the computer executes the distribution system operation management system 1. It functions as each means.

  Furthermore, the auxiliary storage device 33 stores in advance various data 40 such as control start voltage, control release voltage, predicted control amount information calculated by pre-calculation, system information, and the like. Note that the predicted control amount information is calculated by executing the “operation plan” process and updated daily.

  Each device such as the operation management subsystem 3 and the loop controller terminal is also realized by an existing or new computer that executes the corresponding operation program and control program, as in the operation management system 1.

  The distributed power source refers to solar power generation, wind power generation, small hydropower generation, waste power generation, biomass power generation, micro gas turbine, fuel cell, and the like. Hereinafter, in the present embodiment, the control of the photovoltaic inverter will be described as an example. However, the type of the distributed power source to which the present invention can be applied is not particularly limited as long as it performs hysteresis-like control.

  These devices are connected to each other through a communication network 12 such as an optical fiber. In normal operation, the operation management system 1 mainly provides various commands and data to the LPC 2 and the supply and demand IF to optimize the voltage. Is realized. Also, depending on the situation, the supply and demand IF controls the distributed power source autonomously and performs services such as harmonic suppression and reactive power adjustment in the local area.

  According to the operation management system 1 and the demand point system configured as described above, the power generation amount of the distributed power source and the actual load value of the customer (hereinafter referred to as the customer) collected from each supply and demand IF. The optimum control amount for voltage optimization of the loop controller 2 is determined based on the information). The collection interval of customer information depends on the scale of the demand place system, and may be an optimum collection interval (for example, 30 minutes) according to the scale of the demand place system. For example, when the scale is large, the amount of data to be collected increases, and the calculation time for determining the control amount also increases. Therefore, it is preferable to increase the collection interval.

  Here, as an index for voltage optimization (suppression of the voltage fluctuation range) of the loop controller 2, the maximum value and the minimum value are extracted from the voltages of the boundaries (nodes) of all the sections, and the difference between them is extracted. The obtained value can be used as an evaluation index for voltage optimization.

More specifically, based on the demand place system explanatory diagram shown in FIG.
(1) First, before starting operation, the configuration of the distribution system to be managed, for example, the impedance of the line, the connection status, the connection position of the customer, the installation position of the LPC, etc. are input to the operation management program, It is stored in the storage device as configuration information.
(2) Next, the power supply / demand interface 4 measures the power consumption (active power) and reactive power of all the consumers including those who do not have a distributed power source, and transmits them to the operation management system 1.
(3) The power consumption and reactive power sent from all points are input to the operation management program.
(4) Next, the operation program changes the outputs (active power and two reactive powers) 2 of all the loop controllers (LPC1 to 5 in the above figure) 2 at a constant interval to derive all combinations.
For example, it is performed as shown in an example in which combinations are derived in increments of 10 in the range of 0 to 50 shown below.
LPC1 LPC2 LPC3 LPC4 LPC5
Valid invalid 1 Invalid 2 Valid invalid 1 Invalid 2 Valid invalid 1 Invalid 2 Valid invalid 1 Invalid 2 Valid invalid 1 Invalid 2
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
10 0 0 0 0 0 0 0 0 0 0 0 0 0 0
20 0 0 0 0 0 0 0 0 0 0 0 0 0 0
30 0 0 0 0 0 0 0 0 0 0 0 0 0 0
40 0 0 0 0 0 0 0 0 0 0 0 0 0 0
50 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 10 0 0 0 0 0 0 0 0 0 0 0 0 0
10 10 0 0 0 0 0 0 0 0 0 0 0 0 0
20 10 0 0 0 0 0 0 0 0 0 0 0 0 0
30 10 0 0 0 0 0 0 0 0 0 0 0 0 0
40 10 0 0 0 0 0 0 0 0 0 0 0 0 0
50 10 0 0 0 0 0 0 0 0 0 0 0 0 0
0 20 0 0 0 0 0 0 0 0 0 0 0 0 0
10 20 0 0 0 0 0 0 0 0 0 0 0 0 0
20 20 0 0 0 0 0 0 0 0 0 0 0 0 0
30 20 0 0 0 0 0 0 0 0 0 0 0 0 0
40 20 0 0 0 0 0 0 0 0 0 0 0 0 0
50 20 0 0 0 0 0 0 0 0 0 0 0 0 0
0 30 0 0 0 0 0 0 0 0 0 0 0 0 0
10 30 0 0 0 0 0 0 0 0 0 0 0 0 0
20 30 0 0 0 0 0 0 0 0 0 0 0 0 0
30 30 0 0 0 0 0 0 0 0 0 0 0 0 0
40 30 0 0 0 0 0 0 0 0 0 0 0 0 0
50 30 0 0 0 0 0 0 0 0 0 0 0 0 0
0 40 0 0 0 0 0 0 0 0 0 0 0 0 0
10 40 0 0 0 0 0 0 0 0 0 0 0 0 0
20 40 0 0 0 0 0 0 0 0 0 0 0 0 0
30 40 0 0 0 0 0 0 0 0 0 0 0 0 0
40 40 0 0 0 0 0 0 0 0 0 0 0 0 0
50 40 0 0 0 0 0 0 0 0 0 0 0 0 0
0 50 0 0 0 0 0 0 0 0 0 0 0 0 0
10 50 0 0 0 0 0 0 0 0 0 0 0 0 0
20 50 0 0 0 0 0 0 0 0 0 0 0 0 0
30 50 0 0 0 0 0 0 0 0 0 0 0 0 0
40 50 0 0 0 0 0 0 0 0 0 0 0 0 0
50 50 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 10 0 0 0 0 0 0 0 0 0 0 0 0
10 0 10 0 0 0 0 0 0 0 0 0 0 0 0
20 0 10 0 0 0 0 0 0 0 0 0 0 0 0
30 0 10 0 0 0 0 0 0 0 0 0 0 0 0
40 0 10 0 0 0 0 0 0 0 0 0 0 0 0
50 0 10 0 0 0 0 0 0 0 0 0 0 0 0
0 0 20 0 0 0 0 0 0 0 0 0 0 0 0
10 0 20 0 0 0 0 0 0 0 0 0 0 0 0
20 0 20 0 0 0 0 0 0 0 0 0 0 0 0
30 0 20 0 0 0 0 0 0 0 0 0 0 0 0
40 0 20 0 0 0 0 0 0 0 0 0 0 0 0
50 0 20 0 0 0 0 0 0 0 0 0 0 0 0
・
・
・
50 50 50 50 50 50 50 50 50 50 50 50 50 50 50

(5) Then, for each case described above, the tidal current calculation included in the operation program is performed, and the voltages (V1) at all points in FIG. 11, that is, the connection points of customers, the connection points of distributed power sources, and the connection points of LPCs. ~ VN).
(6) Further, for each case, V _all is calculated from the calculation result of (5) using Formula 1 as an evaluation item, and the maximum value and the minimum value are searched from among the voltages at all points to obtain a difference. Implement all cases.
(7) The case (optimum case) which becomes Formula 2 among all cases is searched.
At this time, the central control target voltage (upper limit value) is between the control start voltage and the control release voltage at all points.
The relationship.
(8) The control output (active power and reactive power) of all LPCs in the optimal case obtained in (7) above is sent from the operation management system to all LPCs. For example, it becomes the following numerical values.
LPC1 LPC2 LPC3 LPC4 LPC5
Valid Invalid 1 Invalid 2 Valid Invalid 1 Invalid 2 Valid Invalid 1 Invalid 2 Valid Invalid 1 Invalid 2 Valid Invalid 1 Invalid 2
10 20 30 30 20 10 50 40 30 20 10 20 30 40 50
(9) By implementing (2) to (8) at regular time intervals, voltage optimization of the distribution system is realized (refer to demand area system analysis program, LPC and LDC control amount determination program, non-patent document 3). . For the tidal current calculation, for example, a tidal current calculation based on the Newton-Raphson method can be used, but the tidal current calculation method is not particularly limited.

  Note that the optimal control amount obtained is compared with the predicted control amount information calculated in advance, and if they match, the information is not transmitted to the LPC 2, the transformer 5 of the substation, and the supply and demand IF 4, but they are different. Only in this case, the control amount and power flow / voltage information obtained for each device may be transmitted.

  As described above, the operation related to the voltage control of the demand place system that performs the loop mesh operation via the loop controller 2 is the operation management system that performs the centralized control of the distribution system, and the distributed power source starts the voltage rise suppression control. The voltage value between the control start voltage, which is a voltage value, and the control release voltage, which is equal to or lower than the control start voltage and is the voltage value at which the distributed power supply cancels the voltage rise suppression control, is determined by the loop controller. The central control target voltage that is the upper limit value is set, and the output amounts of the active power and reactive power from the loop controller are controlled so as to suppress the voltage in the distribution system to the central control target voltage.

  First, a case where voltage optimization control in the system is performed only by the loop controller 2 will be described. As described above, the voltage optimization by the LPC 2 is an upper limit value for each point of the high-voltage system based on the system information stored in the auxiliary storage device 33 in advance by the operation management system 1 and the customer information received from the supply-demand IF 4. (Centralized control target voltage) is set, and when this value is exceeded, the output amount of active power and reactive power injected from the LPC2 is controlled so that the centralized control target voltage is suppressed, and the centralized control target voltage is maintained. This is because the injection amount is controlled so as to be possible. That is, voltage optimization by LPC2 considers the increase in the low-voltage system uniformly, sets an upper limit value for each point of the high-voltage system, and suppresses the upper limit value or less when this upper limit value is exceeded. Control is performed. The control timing of the loop controller 2 is discrete, and the control interval is not particularly limited and can be determined as appropriate by the system operator. For example, at an interval of about 10 seconds to 3 minutes. Preferably it is done.

  As shown in FIG. 4A, the voltage optimization by the loop controller 2 increases the voltage due to power generation, and the voltage at each point of the high voltage system (each node on the power flow calculation system data) is the central control target of the LPC2. When the voltage is exceeded (indicated by arrow a, the same applies hereinafter), when the next LPC 2 control timing is reached (arrow b), voltage optimization control is started and the voltage is lowered to the central control target voltage (arrow c). , That value is maintained (arrow d).

  Next, the case where the voltage rise suppression control of the photovoltaic power generation inverter is performed only by the reactive power control will be described. Voltage rise suppression control sets an upper limit value (control start voltage) for the voltage at the connection point of the low-voltage system, and when it exceeds that, injects (outputs) reactive power and controls it below the upper limit value. Therefore, the reactive power output is kept constant. When the voltage further decreases from that state and becomes equal to or lower than the lower limit value (control release voltage) of the increase suppression function, the reactive power output is decreased until the voltage becomes equal to or higher than the control release voltage value. In addition, for suppressing the voltage increase of the inverter for photovoltaic power generation, for example, a method of performing active power control and a control method using a power factor as a determination criterion are conceivable. As long as this is performed, the voltage control method is not particularly limited. It is necessary to determine each set value so that the voltage value of the low voltage system when the high voltage system side is limited to the upper limit value or less by the LPC 2 is between the upper limit value and the release voltage value of the voltage rise suppression function. At this time, the control output of the LPC 2, that is, the LPC capacity can be reduced.

  The control start voltage and the control release voltage can be arbitrarily set by the consumer, and the set values differ for each consumer. However, the upper limit of the control start voltage of the distributed power supply is determined (up to 107V), and setting the control release voltage low will reduce the power generation efficiency and disadvantage for the consumer, so the range of that value Is limited and can be treated as a general value.

  Moreover, the inverter for photovoltaic power generation is controlled continuously while the control by the loop controller 2 is discrete. Therefore, when both controls are performed within the same system, the photovoltaic power generation output always precedes and controls the low-voltage side voltage, and then the LPC 2 performs the high-voltage side control.

  Based on the above characteristics of voltage optimization by the loop controller 2 and voltage rise suppression control by the inverter for photovoltaic power generation, the inventors of the present application have made various studies. As described below, the centralized control target voltage of the loop controller 2 is as follows. It was newly found that cooperative control is possible by setting. Hereinafter, the set values of the centralized control target voltage of the loop controller 2 and the control start voltage and control release voltage of the photovoltaic power generation inverter for coordinating these two controls will be described with reference to FIG.

  First, as shown in FIG. 5A, if the centralized control target voltage is set higher than the control start voltage, the voltage optimization control of the loop controller 2 will not work. That is, when the voltage rises due to power generation and becomes equal to or higher than the central control target voltage (arrow a), voltage rise control by the photovoltaic power generation inverter and voltage control by LPC2 work (arrow b). Since the control of the LPC 2 is discrete, in practice, only the control of the inverter for photovoltaic power generation actually works. However, when the voltage drops below the central control target voltage, the control by the LPC 2 is canceled, so only the voltage increase suppression control by the inverter for photovoltaic power generation is performed (arrow c), and both controls are not coordinated.

  On the other hand, as shown in FIG. 5B, if the centralized control target voltage is set lower than the control release voltage, the voltage increase suppression control of the inverter for photovoltaic power generation does not work. That is, when the voltage rises due to power generation and becomes equal to or higher than the centralized control target voltage (arrow a), voltage rise suppression control by the photovoltaic power generation inverter and voltage optimization control by LPC2 work (arrow b). Accordingly, the cooperative control is in a state up to the control release voltage. However, since the voltage increase suppression control is released when the control release voltage is lower than the control release voltage, the control is performed only by the LPC 2 (arrow c). As a result, the voltage is suppressed and maintained up to the central control target voltage by the LPC 2 (arrow d). That is, the cooperative control is performed temporarily, and only the voltage optimization control of the LPC 2 works. As described above, when only the voltage optimization control by the LPC 2 is activated, the required capacity of the LPC 2 is increased and the cost is increased.

  However, when the high-voltage system side is controlled below the upper limit value by the LPC2, the voltage value of the low-voltage system is between the upper limit value and the release voltage value of the voltage rise suppression function, in other words, the central control target voltage is controlled. By setting between the start voltage and the control release voltage, the control by the inverter for photovoltaic power generation and the control by the LPC 2 can be coordinated.

  That is, in the voltage optimization control of the LPC2, the control amounts of the active power and reactive power of each LPC2 may be determined so that the centralized control target voltage is set in the range of the control start voltage and control release voltage of the distributed power source. . In the operation of voltage optimization, the operation management system has already configured the configuration of the target system based on the load and power generation information of each customer collected from the supply and demand interface installed for each customer or customer group. The active power / reactive power command value of each loop controller that meets the above conditions is determined and transmitted. The loop controller performs an operation of controlling the output at a constant interval according to the command value sent.

  In this case, as shown in FIG. 5 (c), when the voltage rises due to power generation and becomes equal to or higher than the central control target voltage (arrow a), voltage rise suppression control by the inverter for photovoltaic power generation and voltage optimization control by LPC2 are performed. In operation (arrow b), the voltage is maintained to the central control target voltage by the LPC 2 (arrow c). In this case, since the voltage rise suppression control is not released, the two controls are in a coordinated state.

  Here, there is a certain range between the control start voltage and the control release voltage, but the value for the central control target voltage between them is the purpose of system control in addition to system information and customer information. It is preferable that the system administrator decides arbitrarily according to.

  For example, it is desirable that the central control target voltage is as close to the control release voltage as possible in that the voltage of the entire system can be kept low. However, keeping the voltage of the LPC 2 low leads to an increase in the operation cost of the LPC 2, so that the operation in consideration of the cost is required to determine the central control target voltage.

  According to the operation method of the power distribution system of the present embodiment described above, cooperative control of the photovoltaic power generation inverter and the LPC 2 is enabled, and the control output of the LPC 2 can be reduced. In addition, since it is not necessary to send a direct command to the distributed power supply, and the control is to send a direct command only to the LPC 2, the amount of communication compared to a configuration in which the command is directly sent to all the distributed power sources. Can be greatly reduced, and the communication load can be reduced.

  The above-described embodiment is a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without departing from the gist of the present invention. For example, in the present embodiment, the power distribution system has been described as an example of a distribution system in which a distributed power source is connected to the low-voltage system side and a voltage control device is installed on the high-voltage system side. The present invention is not limited to a distribution system, and can be applied to any distribution system in which a distributed power source that performs at least hysteresis-like control and a voltage control device that is a target of centralized control are installed. In addition, although the loop controller has been mainly described as an example of the voltage control device that is the target of centralized control, it is not limited to this, and the voltage control device is not limited to this. You may make it use the voltage control apparatus in which voltage optimization control is possible. Further, the centralized control target voltage can be set as a fixed value for operation. In this case, since voltage optimization according to the load amount and power generation amount of the consumer is not made, as a result, the required capacity of the LPC 2 is smaller than when the control amount is calculated and reflected every time the customer information is received. The control system can be simplified though it increases.

  In the above-described embodiment, the output amount is transmitted from the operation management system 1 to the loop controller control terminal 11 that controls the loop controller 2. However, voltage control of a static reactive power compensator or the like is performed. When autonomously controlling based on the output amount of reactive power received by the device, the operation management system 1 may transmit the output amount directly to the voltage control device, The output amount may be transmitted to the control device. In addition, when the voltage control device targeted for centralized control performs voltage optimization control only by reactive power output, the amount of reactive power output is controlled, and when voltage optimization control is performed by active power and reactive power output, The output amounts of active power and reactive power may be used as control amounts.

Example 1
Using the distribution system model shown in FIG. 7, an experiment was conducted to confirm the effectiveness of the distribution system operation management system of the present invention.

  A distributed power source 10 (50 kW) simulating solar power generation is connected, the system voltage is increased, and the control of both the LPC 2 and the distributed power source 10 that operate the demand point system is operated in response to this increase. While confirming the effectiveness of the operation management system of the power distribution system of the present invention, it was compared with the case where only one of them was controlled.

  The control amount of the inverter type power supplies 8a to 8c and the control amount of the LPC 2 are shown in FIG. 8, and the voltage at the interconnection point is shown in FIG. As shown in FIG. 9, when the voltage at the interconnection point of the inverter 8c is seen, it can be seen that there is almost no difference between the case of both controls and the case of only the control of the LPC2. On the other hand, as shown in FIG. 8, the inverter power supplies 8a, 8b, and 8c do not change for both control amounts, but when the cooperative control is performed by the operation management system of the distribution system of the present invention, the control of the loop controller 2 It was confirmed that the output was reduced by about 10 kVA.

  From the above, it can be seen that both controls are coordinated while maintaining the control effect. According to this experiment, the effectiveness of the present invention can be confirmed. In this embodiment, the voltage rise suppression control of the photovoltaic inverter is controlled only by the reactive power control. However, the effectiveness of other control methods was confirmed in the same manner.

It is a figure which shows an example of a structure of the operation management system of a power distribution system. It is an example of the functional block diagram of the operation management system of the power distribution system of this embodiment. It is a figure which shows an example of the hardware constitutions of the operation management system of the power distribution system of this embodiment. (A) It is a figure for demonstrating the case where the voltage optimization of a system | strain is performed only by the loop controller. (B) It is a figure for demonstrating the case where the voltage rise suppression control of a distributed power supply is performed. The horizontal axis represents time, and the vertical axis represents voltage. (A) It is a figure for demonstrating the case where centralized control target voltage is set higher than control start voltage. (B) It is a figure for demonstrating the case where centralized control target voltage is set lower than control cancellation | release voltage. (C) It is a figure for demonstrating the case where the voltage optimization control by a loop controller and the voltage rise suppression control by a distributed power supply cooperate. The horizontal axis represents time, and the vertical axis represents voltage. It is a flowchart which shows an example of the process which the operation management program of the power distribution system of this invention performs. 1 is a model diagram of a power distribution system in Example 1. FIG. 6 is a graph illustrating an example of a result of a control amount of an inverter type power source and a control amount of a loop in Example 1. 3 is a graph showing a voltage at a connection point in Example 1. It is a figure which shows an example of a loop controller. It is explanatory drawing which shows embodiment of a more specific demand place system.

Explanation of symbols

1 Operation management system 2 Loop controller (LPC)
3 Operation Management Subsystem 4 Supply / Demand Interface 11 Loop Controller Terminal 20 Customer Information Acquisition Unit 21 Control Amount Determination Unit 22 Control Amount Determination Unit 23 Control Amount Transmission Unit

Claims (7)

  In a distribution system in which a distributed power source is connected to the low-voltage system side and a voltage control device is installed on the high-voltage system side, an operation management system that performs centralized control of the distribution system, the distributed power source performs voltage rise suppression control. A voltage value between a control start voltage that is a voltage value to be started and a control release voltage that is equal to or less than the control start voltage and that is a voltage value at which the distributed power source cancels the voltage rise suppression control; A centralized control target voltage that is an upper limit value of the voltage optimization control by the control, and the amount of reactive power output from the voltage control device is controlled to suppress the voltage in the distribution system to the centralized control target voltage, Operation management method for the distribution system.   In a distribution system in which a distributed power source is connected to the low-voltage system side and a voltage control device is installed on the high-voltage system side, an operation management system that performs centralized control of the distribution system is configured to generate power from the distributed power source through a supply-demand interface. And the actual load values of all consumers are received as customer information, and the central control target voltage, which is the upper limit value of voltage optimization control of the voltage control device, is calculated based on the customer information. And a control start voltage that is a voltage value at which the distributed power source starts voltage rise suppression control, and a control release voltage that is equal to or lower than the control start voltage and that is a voltage value at which the distributed power source releases voltage rise suppression control. And the amount of reactive power output from the voltage control device is controlled so as to suppress the voltage in the distribution system to the central control target voltage. Operations management method of the system.   The power distribution system operation management method according to claim 1, wherein the centralized control target voltage is made to approach the control release voltage.   The voltage control device is a loop controller, and transmits the output amounts of active power and reactive power from the loop controller to the control device of the loop controller so as to suppress the voltage in the distribution system to the central control target voltage. The power distribution system operation management method according to any one of claims 1 to 3, wherein:   In a distribution system in which a distributed power source is connected to the low-voltage system side, a voltage control device is installed on the high-voltage system side, and an operation management system that performs centralized control in the system and a supply-demand interface are connected through a communication network The management system receives from the supply and demand interface the power generation amount of the distributed power source and the measured value of the load amount of all consumers as customer information, and an upper limit of voltage optimization control of the voltage control device A control start voltage that is a voltage value at which the distributed power source that has been stored in the storage device and starts the voltage rise suppression control is calculated based on the customer information, and the centralized control target voltage that is a value is calculated. Calculated as a value between the control start voltage and a control release voltage that is a voltage value at which the distributed power source releases the voltage rise suppression control. Control amount determination means for calculating an output amount of reactive power from the voltage control device for suppressing the voltage in the distribution system to the centralized control target voltage, and the output amount to the voltage control device or the voltage An operation management system for a distribution system, comprising: a control amount transmission unit that transmits the control device to a control device.   The voltage control device is a loop controller, and the control amount determination means calculates the output amounts of active power and reactive power from the loop controller so as to suppress the voltage in the distribution system to the central control target voltage. The power distribution system operation management system according to claim 5.   In a distribution system in which a distributed power source is connected to the low-voltage system side, a voltage control device is installed on the high-voltage system side, and an operation management system that performs centralized control in the system and a supply-demand interface are connected through a communication network A consumer information reception process for causing the management system to receive the actual power generation amount of the distributed power source and the measured value of the load amount of all consumers as customer information from the supply and demand interface, the upper limit value of voltage optimization control of the voltage control device A control start voltage that is a voltage value at which the distributed power source, which is stored in a storage device in advance, starts a voltage increase suppression control, and the centralized control target voltage is a power flow calculation based on the customer information Calculated as a value between a control solution start voltage and a control release voltage that is a voltage value at which the distributed power supply releases the voltage rise suppression control. Control amount determination processing for calculating the output amount of the reactive power of the voltage control device for suppressing the voltage in the distribution system to the centralized control target voltage and the output amount to the voltage control device or the voltage control device An operation management program for a power distribution system that executes control amount transmission processing to be transmitted to the control device.