JP2019208304A - Power control device, power control system, reactive power controller, and power control method - Google Patents

Abstract

To obtain a power control device by which unbalance in the reactive power control amount among reactive power controllers can be suppressed.SOLUTION: The power control device includes a simulation unit 12 that, for each of combinations of setting values for a plurality of reactive power controllers which are installed by consumers and are connected to a power system, calculates a voltage distribution of the power system, a setting value determination unit 13 that determines a setting value for each of the reactive power controllers on the basis of the voltage distribution, and a communication unit 14 that transmits, to the reactive power controller, the setting value determined by the setting value determination unit 13. The setting values are determined at least two different times, and are transmitted to each of the reactive power controllers.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a power control apparatus, a power control system, a reactive power controller, and a power control method for controlling a plurality of reactive power controllers.

  In recent years, distributed power sources such as photovoltaic power generation facilities have increased, and these distributed power sources are often controlled by a power conditioner (PCS). The power conditioner has a function of adjusting a voltage by outputting reactive power. Conventionally, a plurality of power conditioners connected to an electric power system determines whether or not reactive power needs to be controlled based on their own end voltage values. For this reason, since the voltage in the power system is not uniform, the control amount of reactive power is biased depending on the interconnection location that is the position in the power system to which the power conditioner is connected.

  In Patent Document 1, in order to equalize the control amount of reactive power between power conditioners, a difference in the self-end voltage between power conditioners at a certain time is measured, and each power conditioner is based on the measured difference. A technique for setting the settling value is disclosed.

JP 2012-70598 A

  The voltage distribution in the power system changes depending on the operation of a voltage control device such as an SVR (Step Voltage Regulator), a change in load, and the like. However, according to the technique described in Patent Document 1, since the settling value of each power conditioner is set based on the difference in the self-end voltage between the power conditioners at a certain past time, the settling value is set. In some cases, the actual voltage distribution may be different from the actual voltage distribution, and as a result, the amount of reactive power controlled by the power conditioner, which is a reactive power controller, may be uneven.

  This invention is made | formed in view of the above, Comprising: It aims at obtaining the power control apparatus which can suppress the nonuniformity of the control amount of the reactive power between reactive power controllers.

  In order to solve the above-described problems and achieve the object, a power control apparatus according to the present invention is provided for each combination of set values of a plurality of reactive power controllers installed by a consumer and connected to the power system. A voltage distribution calculation unit that calculates the voltage distribution of the power supply, and a settling value determination unit that determines a settling value to be set in the reactive power controller based on the voltage distribution. The power control apparatus includes a communication unit that transmits the set value determined by the set value determination unit to the reactive power controller, and determines the set value and transmits the set value to the reactive power controller at least at two different times. To do.

  According to the present invention, it is possible to suppress unevenness in the amount of reactive power control between reactive power controllers.

The figure which shows the structural example of the power control system concerning Embodiment 1. FIG. The figure which shows the structural example of the central server of Embodiment 1. FIG. The figure which shows the structural example of the power generation equipment of Embodiment 1. The figure which shows the structural example of the computer system which implement | achieves the central server of Embodiment 1. FIG. The flowchart which shows an example of the power control processing procedure in the central server of Embodiment 1. The figure which shows the set value of the reactive power controller of Embodiment 1. The figure which shows the concept of the voltage distribution calculated by the simulation part of Embodiment 1. FIG. 7 is a conceptual diagram showing a set value combination used for calculating the voltage distribution in FIG. The figure which shows an example of the reactive power which the reactive power controller of Embodiment 1 outputs The figure which shows an example of the setting of the time constant in the reactive power controller of Embodiment 1. The figure which shows the structural example of the power control system concerning Embodiment 2. FIG. The figure which shows the structural example of the central server of Embodiment 2. FIG. The flowchart which shows an example of the power control procedure of the central server of Embodiment 2.

  Hereinafter, a power control device, a power control system, a reactive power controller, and a power control method according to embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram of a configuration example of the power control system according to the first embodiment of the present invention. In FIG. 1, an upper system 1, a distribution line 8 connected to the upper system 1, an LRT (Load Ratio control Transformer) 2, and an SVR 3 that controls the voltage of the distribution line 8. The pole transformers 4-1 and 4-2 connected to the distribution line 8 are power system facilities installed by a business operator. The LRT 2 is installed in the substation, transforms the electric power supplied from the host system 1 and outputs it to the distribution line 8. In FIG. 1, one SVR 3 is illustrated, but the number of SVRs connected to the distribution line 8 may be any number. In addition to the SVR 3, an SVC (Static Var Compensator) that controls the voltage in the distribution line 8 may be connected. The number of pole transformers 4-1 and 4-2 is not limited to the example of FIG.

  The SVR 3 is a voltage control device that controls the voltage in the distribution line 8 so that the voltage in the distribution line 8 falls within a predetermined appropriate range. The pole transformers 4-1 and 4-2 convert, for example, a voltage of a high voltage system such as 3300V to 6600V into a voltage supplied to a general consumer, for example, a voltage of a low voltage system such as 100V. Generally, an appropriate range (hereinafter referred to as an appropriate range in a low-voltage system) is defined for the voltage at the power receiving end of general consumers. An appropriate range in the low-voltage system is, for example, 95V to 107V. For example, the appropriate range of the voltage in the distribution line 8 is determined by conversion so that the voltage at the power receiving end in the general consumer falls within the proper range in the low-voltage system.

  Consumer equipment 5-1 and 5-2 are connected to the distribution line 8 of the power system via pole transformers 4-1 and 4-2, respectively. The customer facility 5-1 has a load 6-1 and a power generation facility 7-1 having a function as a reactive power controller capable of outputting reactive power. Similarly to the customer facility 5-1, the customer facility 5-2 includes a load 6-2 and a power generation facility 7-2 having a function as a reactive power controller capable of outputting reactive power. . However, the load 6-1 and the load 6-2 may be different in configuration, power consumption, and the like, and the rated capacity may be different between the power generation equipment 7-1 and the power generation equipment 7-2. Hereinafter, when each of the customer facilities 5-1 and 5-2 is shown without being individually distinguished, it is referred to as a customer facility 5 and each of the loads 6-1 and 6-2 is shown without being individually distinguished. Sometimes, it is described as a load 6, and each power generation facility 7-1, 7-2 is described as a power generation facility 7 when not shown separately.

  The power control system of the present embodiment includes a central server 10 that is a power control device, and a reactive power controller that is controlled by the central server 10. The reactive power controller is, for example, a power conditioner included in the power generation facility 7 as described later. Hereinafter, an example in which the reactive power controller is a power conditioner in a photovoltaic power generation facility will be described. The central server 10 and the reactive power controller controlled by the central server 10 are connected by a communication network. The communication network may be the Internet or a dedicated network, or a part thereof may be a dedicated network and part may be the Internet, and there is no particular limitation on the form of the communication network.

  The number of customer facilities 5 connected to each pole transformer 4-1 and 4-2 is not limited to the example shown in FIG. Moreover, although the distribution line 8 of an electric power system is generally connected with the customer equipment which has a load and is not equipped with power generation equipment via pole transformers 4-1 and 4-2, The illustration of customer facilities is omitted.

  FIG. 2 is a diagram illustrating a configuration example of the central server 10. As illustrated in FIG. 2, the central server 10 includes a prediction unit 11, a simulation unit 12, a set value determination unit 13, a communication unit 14, and a storage unit 15. The prediction unit 11 predicts a load amount and a power generation amount that are power amounts consumed by the load in the power system. Specifically, the prediction unit 11 predicts a load waveform and a PV (PhotoVoltaics) power generation waveform at each point on the distribution line 8. The load waveform indicates the amount of power consumed by the load connected to the distribution line 8 for each time zone, and the PV power generation waveform indicates the amount of power generated by the solar power generation facility connected to the distribution line 8 for each time zone. . That is, the load waveform and the PV power generation waveform are waveforms in which the horizontal axis represents time and the vertical axis represents electric energy. The vertical axis of the load waveform and the PV power generation waveform may be electric power instead of electric energy.

  Based on the load waveform and the PV power generation waveform, the simulation unit 12 performs a simulation for each combination of set values of the reactive power controller to obtain a voltage distribution in the distribution line 8. That is, the simulation unit 12 is a voltage distribution calculation unit that calculates the voltage distribution of the power system for each combination of set values of the plurality of reactive power controllers. The set value determination unit 13 determines the set value of each reactive power controller based on the voltage distribution calculated by the simulation unit 12. The communication unit 14 transmits the set value determined by the set value determining unit 13 to each reactive power controller. The central server 10 according to the present embodiment determines the set value and transmits it to the reactive power controller at at least two different times. The storage unit 15 stores information used for processing by the prediction unit 11, the simulation unit 12, and the settling value determination unit 13. Details of the operation of the central server 10 will be described later.

  FIG. 3 is a diagram illustrating a configuration example of the power generation facility 7. The power generation facility 7 generates power and outputs a DC power obtained by the power generation, and a reactive power control that is a power conditioner that converts the DC power output from the power generation apparatus 20 into AC power and outputs the AC power. And a vessel 21. The reactive power controller 21 is an example of a reactive power controller that is installed by a consumer and connected to the power system. The reactive power controller 21 is connected to the power system. Specifically, the low-voltage distribution line connected to the pole transformer and the distribution line 8 are connected via the pole transformer. The AC power output from the reactive power controller 21 can be used by the load 6 of the customer facility 5. The reactive power controller 21 can also reverse-flow AC power through the power system. The reactive power controller 21 can output active power and reactive power as AC power.

  The reactive power controller 21 includes a power control unit 22, a communication unit 23, and a storage unit 24. The power control unit 22 converts the DC power output from the power generation device 20 into AC power and adjusts the reactive power to be output. The power control unit 22 generally includes a power converter that converts DC power output from the power generation device 20 into AC power, and a control unit that controls the power converter, and the control unit controls the power converter. Thus, the reactive power to be output is controlled. The communication unit 23 communicates with the central server 10. The communication unit 23 passes the set value received from the central server 10 to the power control unit 22. The power control unit 22 controls the reactive power to be output according to the set value received from the central server 10 via the communication unit 23.

  Next, the hardware configuration of the central server 10 will be described. The central server 10 is realized by a computer system, that is, a computer. In the central server 10 of the present embodiment, the computer system functions as the central server 10 by executing a power control program that is a program in which processing in the central server 10 is described on the computer. FIG. 4 is a diagram illustrating a configuration example of a computer system that implements the central server 10 according to the present embodiment. As shown in FIG. 4, the computer system includes a control unit 101, an input unit 102, a storage unit 103, a display unit 104, a communication unit 105, and an output unit 106, which are connected via a system bus 107. Yes.

  In FIG. 4, a control unit 101 is, for example, a CPU (Central Processing Unit) or the like, and executes a power control program in which processing in the central server 10 of the present embodiment is described. The input unit 102 includes, for example, a keyboard and a mouse, and is used by a computer system user to input various information. The storage unit 103 includes various memories such as a RAM (Random Access Memory) and a ROM (Read Only Memory) and a storage device such as a hard disk. The storage unit 103 includes a program to be executed by the control unit 101 and necessary processes obtained in the process. Store data, etc. The storage unit 103 is also used as a temporary storage area for programs. The display unit 104 is configured by an LCD (liquid crystal display panel) or the like, and displays various screens for the user of the computer system. The communication unit 105 is a receiver and a transmitter that perform communication processing. The output unit 106 is a printer or the like. FIG. 4 is an example, and the configuration of the computer system is not limited to the example of FIG.

  Here, an example of the operation of the computer system until the power control program of the present embodiment becomes executable will be described. In the computer system having the above-described configuration, for example, a power control program is stored in a storage unit from a CD-ROM or DVD-ROM set in a CD (Compact Disc) -ROM or DVD (Digital Versatile Disc) -ROM drive (not shown). 103 is installed. When the power control program is executed, the power control program read from the storage unit 103 is stored in the main storage area of the storage unit 103. In this state, the control unit 101 executes processing as the central server 10 according to the present embodiment in accordance with a program stored in the storage unit 103.

  In the above description, a program describing processing in the central server 10 is provided using a CD-ROM or DVD-ROM as a recording medium. However, the present invention is not limited to this. Depending on the capacity, for example, a program provided by a transmission medium such as the Internet via the communication unit 105 may be used.

  The prediction unit 11, the simulation unit 12, and the set value determination unit 13 illustrated in FIG. 2 are realized by the control unit 101 in FIG. Further, the storage unit 103 is also used for realizing the prediction unit 11, the simulation unit 12, and the settling value determination unit 13. 2 is realized by the storage unit 103 shown in FIG. 4, and the communication unit 14 shown in FIG. 2 is realized by the communication unit 105 shown in FIG.

  Of the hardware configuration of the reactive power controller 21, components other than the power converter in the power control unit 22 are realized by a processing circuit. The processing circuit may be the same as the computer system shown in FIG. 4 or may include a dedicated processing circuit. When there are functional units realized by software in the reactive power controller 21, these functional units are executed by the control unit 101 in the same manner as the central server 10 described above. Is realized.

  Next, the operation of the central server 10 of this embodiment will be described. In order to control the reactive power output from each reactive power controller 21 in the power system, the central server 10 of the present embodiment determines the set value of each reactive power controller 21 and sets the set value to each reactive power controller 21. Transmit to reactive power controller 21. That is, the central server 10 according to the present embodiment commands each reactive power controller 21 to set a set value.

  FIG. 5 is a flowchart illustrating an example of a power control processing procedure in the central server 10. As shown in FIG. 5, the prediction unit 11 of the central server 10 predicts a load waveform and a PV power generation waveform (step S1). Specifically, the prediction unit 11 is based on facility information indicating, for example, the connection position and capacity of each facility connected to the distribution line 8, the contracted capacity corresponding to each customer facility connected to the distribution line 8, and the like. Thus, a load waveform and a PV power generation waveform for a certain period in the future at each point of the distribution line 8 are predicted. For example, the fixed period can be set to one day, and the load waveform and the PV power generation waveform can be set to a load amount and a power generation amount every 30 minutes, respectively. The fixed period may be several minutes, several hours, or several days, and any value can be used. The time zone that is the step of the horizontal axis of each waveform is not limited to 30 minutes.

  The prediction unit 11 may acquire the measured past actual load amount and the past PV actual power generation amount, and predict the load waveform and the PV power generation waveform based on these. As the past actual load amount and the past PV actual power generation amount, for example, a measurement value by a smart meter which is a measurement device provided for automatic meter reading can be used. Alternatively, the reactive power controller 21 may notify the central server 10 of the power generation amount, and these power generation amounts may be used as past PV actual power generation amounts. Any method may be used as a method of predicting the load waveform and the PV power generation waveform from the past actual load amount and the past PV actual power generation amount. For example, conditions such as time zone, day of the week, weather, temperature, etc. The past information may be classified according to the condition, the average value of the past information may be calculated for each condition, and the corresponding average value may be used as the predicted value. AI (Artificial Intelligence) technology, data The prediction may be performed using an analysis technique or the like. The prediction unit 11 may predict the PV power generation waveform using a solar radiation amount prediction curve provided by an external organization such as the Japan Meteorological Agency. Furthermore, the prediction unit 11 may individually predict the load waveform and the PV power generation waveform, or may predict the sum of these waveforms. Hereinafter, the prediction result of the load waveform, the PV power generation waveform, and the total of these waveforms is also referred to as a predicted waveform. Note that the prediction unit 11 calculates one or more predicted waveforms. When calculating two or more predicted waveforms, the predicting unit 11 also calculates an occurrence probability corresponding to each predicted waveform.

Next, the simulation part 12 calculates the evaluation value for every set value combination using the prediction waveform estimated by the prediction part 11 (step S2). The set value combination indicates a combination of set values to be set in each reactive power controller 21. FIG. 6 is a diagram illustrating a set value of the reactive power controller 21. The set values are the slopes k ₁ and k ₂ and the control start voltages V _{ref, 1} and V _{ref, 2 shown} in FIG. In FIG. 6, the horizontal axis represents the self-end voltage in each reactive power controller 21, and the vertical axis represents the reactive power output. As shown in FIG. 6, each reactive power controller 21 does not output reactive power while its own end voltage is higher than V _{ref, 2 and} lower than V _{ref, 1} , and its own end voltage is lower than V _{ref, 2.} Then, the reactive power is output according to the slope k _2, and when the local voltage becomes V _{ref, 1} or more, the reactive power is output according to the slope k ₁ . The set value combination is a combination for each reactive power controller 21 of a set value composed of these gradients k ₁ , k ₂ and control start voltages V _{ref, 1} , V _{ref, 2} .

  Specifically, the simulation unit 12 first calculates a voltage distribution that is a first voltage distribution in the distribution line 8 based on a power flow calculation based on the predicted waveform or a simpler voltage calculation method. Thereby, the self-end voltage in each reactive power controller 21 is made. The simulation unit 12 calculates the reactive power output from each reactive power controller 21 based on the local voltage in each reactive power controller 21 and the set set value, and uses the calculated reactive power to calculate the voltage distribution. Is updated to calculate the updated second voltage distribution. Further, the tap position, which is the control amount by SVR3, may be taken into consideration in the simulation, and if it is possible to acquire information on future control related to SVR3, that is, the scheduled tap position to be commanded, it will be commanded. The tap position of may be reflected.

FIG. 7 is a diagram illustrating the concept of the voltage distribution calculated by the simulation unit 12. The example shown in FIG. 7 shows an example in which three predicted waveforms are calculated. Voltage distributions 201, 202, and 203 indicate voltage distributions corresponding to different predicted waveforms. The voltage distributions 201, 202, and 203 are results calculated based on the power flow calculation based on the predicted waveform or a simpler voltage calculation method, and are recalculated based on the reactive power output from each reactive power controller 21. The voltage distribution before is shown. The horizontal axis in FIG. 7 indicates the distance from the substation, and the vertical axis indicates the voltage. V ₁ was V ₂ indicates the lower limit of the proper range of the voltage indicates the upper limit of the proper range of voltages. The voltage on the vertical axis may be a voltage in the low voltage system, or may be a voltage in the distribution line 8, that is, a voltage converted into a voltage in the high voltage system. FIG. 8 is a conceptual diagram showing a set value combination used for calculating the voltage distribution of FIG. Each set value pattern of set value patterns # 1, # 2,... Indicates a set value combination. One set value pattern # 1 corresponds to one set value combination. As shown in FIG. 8, for each voltage distribution, a set value combination set in each of the reactive power controllers # 1, # 2, # 3, and # 4 is shown. Note that the set values set in one reactive power controller are the four values described above. 7 and 8 show an example in which four reactive power controllers 21 of reactive power controllers # 1, # 2, # 3, and # 4 are controlled.

  Note that the set value may be changed within a period during which the simulation is performed. In this case, each set value pattern includes a timing for changing the set value and set values before and after the change.

  Moreover, the simulation part 12 calculates the evaluation value for evaluating equalization of the controlled variable between reactive power controllers based on the voltage distribution for every combination of a set value. As for the evaluation value, an evaluation value that is highly evaluated can be set when unevenness of the control amount of each reactive power controller 21 is suppressed.

For example, the simulation unit 12 selects a voltage distribution that does not deviate from the appropriate voltage among the calculated voltage distributions, and invalidates one of the following (1) to (8) for the selected voltage distribution. Calculation is performed for each power controller 21, and the variation of the calculated values among the reactive power controllers 21 is used as an evaluation value. As the variation, the variance, standard deviation, difference between the maximum value and the minimum value of the total reactive power controller 21 can be used. The smaller the evaluation value, the higher the evaluation. Thereby, the unfairness between consumers, ie, the nonuniformity of the reactive power control amount of the reactive power controller 21, can be suppressed. Note that the simulation unit 12 may consider the deviation amount from the appropriate voltage range as the evaluation value instead of selecting the voltage distribution that does not cause the deviation from the appropriate voltage first.
(1): Reactive power output amount [kVarh] of the reactive power controller 21
FIG. 9 is a diagram illustrating an example of reactive power output by the reactive power controller 21. As shown in FIG. 9, the reactive power output amount is an integrated value of reactive power for one hour when the horizontal axis represents time and the vertical axis represents reactive power output.
(2): Reactive power output amount of the reactive power controller 21 with the rated ratio This value is obtained by dividing the reactive power output amount of the reactive power controller 21 by the rated value of the reactive power controller 21.
(3): Active power output suppression amount [kWh]
This is the amount of active power to be suppressed. Each reactive power controller 21 may suppress the amount of power generation so as not to exceed the capacity. The suppression amount at this time, that is, the suppressed power generation amount is the effective power output suppression amount.
(4): The active power output suppression amount of the rated ratio is a value obtained by dividing the active power output suppression amount of the reactive power controller 21 by the rated value of the reactive power controller 21.
(5): Active power output suppression rate [%]
This is a value obtained by dividing the effective power output suppression amount by the total effective power output suppression amount and multiplying by 100. The total active power output suppression amount is the sum of the active power output suppression amounts of the total reactive power controller 21.
(6): The occurrence probability of each predicted waveform when a plurality of expected value predicted waveforms of the reactive power output amount considering the occurrence probability are prepared. When predicting a waveform such as a load, the prediction waveform # 1 has a probability of 50%, the prediction waveform # 2 has a probability of 30%, the prediction waveform # 3 has a probability of 20%, and so on. There is also a prediction method for predicting the probability of occurrence of the waveform. When a plurality of predicted waveforms are obtained by such a prediction method, the reactive power output amount of the reactive power controller 21 of a certain set value combination is calculated for each predicted waveform. Then, an expected value corresponding to a certain set value combination is calculated by obtaining the sum of all the predicted waveforms obtained by multiplying the reactive power output amount for each predicted waveform by the occurrence probability.
(7): A weight sum of each value obtained by combining any two or more of (1) to (6) above.
(8): Weight sum of any one of the above values (1) to (6) and the total amount of all reactive power controllers 21 corresponding to the value. For example, if (1), the weight sum of the total amount of reactive power output of all reactive power controllers 21 and the amount of reactive power output of reactive power controllers 21.

  When the active power output suppression amount is used in the evaluation value calculation, the central server 10 acquires the active power output suppression amount from each reactive power controller 21. Note that the evaluation value is not limited to the above example, and an item such as a difference in reactive power output amount within a predetermined period of each reactive power controller 21 may be considered as an item.

  In the power conditioner that is the reactive power controller 21, there is generally a restriction between the active power to be output and the reactive power. Therefore, when the output of reactive power increases, it becomes necessary to suppress the output of active power, and the power generated by the customer cannot be used effectively. Therefore, if the reactive power controller 21 of a specific consumer always increases the amount of reactive power control depending on the position where it is connected to the distribution line 8, there is no sense of fairness among the consumers. It is desirable that the reactive power control amount be equalized so as to be as fair as possible among consumers. However, simply making the reactive power control amount itself the same among consumers is not always fair. The rated capacity of the reactive power controller 21 may vary depending on the customer, and the reactive power controller 21 having a large rated capacity and the reactive power controller 21 having a small rated capacity have the effect of outputting the same reactive power control amount. The degree is different. For this reason, it is also conceivable to determine the set value so as to equalize the amount normalized by the rated capacity. As described above, what is equal may vary depending on the situation. Therefore, an evaluation value may be determined as appropriate so that items to be noted at that time are equalized.

  Returning to the description of FIG. 5, next, the set value determination unit 13 determines the set value of each reactive power controller 21 from the simulation result, that is, the set value and the evaluation value for each predicted waveform (step S <b> 3). Next, the communication unit 14 transmits the set value determined by the set value determination unit 13 to each reactive power controller 21 (step S4). The set value is commanded to each reactive power controller 21 by the above processing.

In addition, although it may set how about the set value pattern at the time of performing a simulation, the setting method as shown to the following (1) to (8) can be considered, for example. By adopting any one of methods (1) to (7), the number of settling value patterns can be reduced as compared with (8).
(1) For example, reactive power controllers 21 are grouped such as a group such as upstream, middle stream, and downstream of a power system, or a group of pole transformer units, and the same set value is used in the same group.
(2) The reactive power controller 21 that performs the reactive power control is changed according to the day or the time zone, and the turn system is set.
(3) Reactive power control results of the reactive power controller 21 are collected, and only the set value of the reactive power controller 21 that is unfair, that is, has a large reactive power control amount, is used as a parameter to be changed.
(4) A part of the settling value is fixed. For example, the difference in the reactive power output start voltage between the reactive power controllers 21 is determined based on the difference in the average value of the local voltage values.
(5) A settling value pattern to be considered is determined using a combination optimization method such as a metaheuristic method that can solve a large-scale combination optimization problem with a practical calculation load.
(6) The discrete interval of the settling value to be set is increased to limit the number of candidates.
(7) Which set value pattern should be used in the past is derived for each weather such as sunny and rain, and the set value pattern is determined according to the weather forecast.
(8) A settable set value combination is set as an all-round set value pattern.

  Further, the central server 10 may periodically perform the operation shown in FIG. 5, that is, the process of determining the set value and transmitting it to the reactive power controller, or obtains weather information indicating the weather forecast and the current weather. Then, the operation shown in FIG. 5 may be performed when the weather changes based on the weather information. That is, the central server 10 may determine whether or not to perform the operation illustrated in FIG. 5 based on the weather. The central server 10 may receive a control result from at least one of the reactive power controllers 21 and determine whether to perform the operation shown in FIG. 5 based on the control result. Whether or not to perform the operation shown in FIG. 5 may be determined by a control unit (not shown) or may be performed by the prediction unit 11.

  As described above, the central server 10 according to the present embodiment controls the plurality of reactive power controllers 21 by the above-described power control method. In this power control method, for each combination of set values of the plurality of reactive power controllers 21, a calculation step for calculating the voltage distribution of the power system and a set value to be set in the reactive power controller based on the voltage distribution are determined. A determination step, and a communication step of transmitting the set value determined by the determination step to the reactive power controller. In addition, the calculation step, the determination step, and the communication step are executed at at least two different times.

  In addition, the simulation unit 12 according to the present embodiment calculates the first voltage distribution of the power system based on the load and the power generation amount predicted by the prediction unit 11, and uses the calculated first voltage distribution as a plurality of reactive powers. The second voltage distribution is calculated by updating each combination of the set values of the controller 21. The set value determination unit 13 determines a set value to be set in the reactive power controller 21 based on the second voltage distribution.

  Next, the operation in the reactive power controller 21 will be described. As described above, the reactive power controller 21 operates based on the settling value received from the central server 10. The reactive power controller 21 may be able to set a time constant, that is, a response time. FIG. 10 is a diagram illustrating an example of setting the time constant in the reactive power controller 21. In FIG. 10, the horizontal axis indicates time, and the vertical axis indicates reactive power output. Ts is the time when the reactive power controller 21 starts outputting reactive power. The control target amount indicates a reactive power output that the reactive power controller 21 sets as a control target. As shown in FIG. 10, when the set value is set, the reactive power controller 21 determines the reactive power output, which is the control target amount, by the self-end voltage, but gradually increases the reactive power from Ts. The target amount can be reached over time. For example, the upper limit of the reactive power output to be increased per unit time is determined such that the upper limit of the reactive power output change amount is 100 VarV per second. The upper limit of reactive power output to be increased per unit time is an example of information indicating response time. In this way, the central server 10 determines the response time so as to reach the control target amount, determines information indicating the response time, transmits the information to the reactive power controller 21, and the power control unit of the reactive power controller 21 Hunting avoidance can be suppressed by controlling the reactive power to be output based on the information 22 indicates the response time. In addition, this makes it possible to avoid the reactive power output operation of only the reactive power controller 21 that started the control a little earlier. The central server 10 may determine the response time and transmit it to each reactive power controller 21, or the response time may be set in the reactive power controller 21 in advance.

  The reactive power controller 21 may transmit one or more of the self-end voltage, the reactive power control record, and the active power output suppression amount to the central server 10. When there is a request from the central server 10, the information described above may be transmitted, may be transmitted periodically, or may be transmitted when the amount described above exceeds a reference value.

  When each reactive power controller 21 receives the information indicating the set value and the response time, these reactive power controllers 21 may reflect them immediately or specify the time to be reflected by the central server 10, and each reactive power controller 21 specifies These may be reflected in the scheduled time.

  As described above, in the present embodiment, the voltage distribution is predicted, the set value of each reactive power controller 21 is determined based on the predicted voltage distribution, and is transmitted to each reactive power controller 21. . For this reason, even when there is a change in the voltage distribution, the probability that a set value corresponding to this change is set is increased, and non-uniformity in the amount of reactive power control among the reactive power controllers can be suppressed.

  In the present embodiment, the voltage distribution is predicted and the set value of each reactive power controller 21 is determined based on the predicted voltage distribution. However, the duty system is simply determined without predicting the voltage distribution. Thus, the reactive power controller 21 that outputs reactive power may be changed every day or every time period. Alternatively, the reactive power controllers 21 may be grouped, and a turn system may be used in which the reactive power controllers 21 in the same group operate on the same date and time in groups. Or it is good also as a duty system which the reactive power controller 21 in the same group operate | moves on a respectively different date.

Embodiment 2. FIG.
FIG. 11 is a diagram of a configuration example of the power control system according to the second embodiment of the present invention. In the example shown in FIG. 11, measuring devices 30-1 and 30-2 for measuring the voltage of the distribution line 8 are added in the power system. The power system of the present embodiment is the same as that of the first embodiment except that measurement devices 30-1 and 30-2 are added. The measuring devices 30-1 and 30-2 are, for example, devices called sensor-equipped switches, but are not limited thereto. The power control system of the present embodiment includes a central server 10a instead of the central server 10 of the embodiment. Constituent elements having the same functions as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and redundant description is omitted. Hereinafter, differences from the first embodiment will be mainly described.

  FIG. 12 is a diagram illustrating a configuration example of the central server 10a according to the present embodiment. The central server 10a of the present embodiment is the same as the central server 10 of the first embodiment except that the measurement information collection unit 16 and the simulation unit 12a are provided instead of the prediction unit 11 and the simulation unit 12. In the present embodiment, the measurement information collecting unit 16 collects measurement information that is a measurement result of the voltage of the distribution line from the measurement devices 30-1 and 30-2 via the communication unit 14, and the collected measurement result is a voltage. The distribution is output to the simulation unit 12a. That is, the measurement information collection unit 16 acquires the measurement result of the voltage in the power system. The simulation unit 12a uses the voltage distribution based on the measurement result collected by the measurement information collection unit 16 to recalculate the voltage distribution of each settling value pattern as in the first embodiment, and the voltage distribution for each settling value pattern. Ask for. In other words, in the present embodiment, the simulation unit 12a, which is a voltage distribution calculation unit, calculates the first voltage distribution of the power system based on the measurement result acquired by the measurement information collection unit 16, and a plurality of reactive power controls. The second voltage distribution is calculated by updating the first voltage distribution for each combination of settling values.

  The hardware configuration of the central server 10a is the same as that of the central server 10 of the first embodiment, and the measurement information collection unit 16 and the simulation unit 12a are realized by the control unit 101 illustrated in FIG.

  FIG. 13 is a flowchart illustrating an example of a power control procedure of the central server 10a according to the present embodiment. As illustrated in FIG. 13, the measurement information collection unit 16 collects measurement information that is a measurement result of the voltage of the distribution line 8 from the measurement devices 30-1 and 30-2 (Step S <b> 11). The simulation unit 12a determines the set value of each reactive power controller 21 using the measurement information collected by the measurement information collection unit 16 (step S12). Specifically, the simulation unit 12a calculates an evaluation value by performing simulation for each set value combination based on the voltage distribution that is the measurement result collected by the measurement information collection unit 16, as in the first embodiment. (Step S12). Steps S3 and S4 are the same as in the first embodiment.

  When the measuring devices 30-1 and 30-2 are sensor-equipped switches, the central server 10a can periodically acquire the latest voltage at each point. In the present embodiment, each time the measurement value is updated, or the simulation is performed using the latest measurement information at regular intervals to determine the set value of each reactive power controller 21, the voltage changes over time. Even in this case, the probability that a settling value corresponding to this change is set is increased, and non-uniformity in the amount of reactive power control among the reactive power controllers can be suppressed.

  Further, the central server 10a may perform a process of determining a set value of each reactive power controller 21 by performing a simulation, or may perform this process at a period different from the update period of the measurement information. Further, the process of performing the simulation using the measurement information to determine the set value of each reactive power controller 21 may be performed when the weather changes, as in the first embodiment, or each reactive power This may be performed when it is determined that the setting value needs to be changed based on the control result from the controller 21. The process of performing a simulation using the measurement information to determine the set value of each reactive power controller 21 may be performed by a control unit (not shown) or may be performed by the measurement information collection unit 16.

  The central server 10a may obtain the voltage distribution using both the voltage measured by the measuring devices 30-1 and 30-2 and the load waveform and the PV power generation waveform described in the first embodiment. For example, the points measured by the measuring devices 30-1 and 30-2 use the measurement information, and for the points not measured such as between the measuring device 30-1 and the measuring device 30-2, the measurement information is used as the load waveform. The voltage may be obtained based on the PV power generation waveform. In addition, the central server 10a may obtain the voltage distribution by further using the measurement value obtained by the smart meter. Furthermore, the central server 10a may acquire the self-end voltage measured by the reactive power controller 21, and obtain the voltage distribution by further using the obtained self-end voltage.

  As described above, in the present embodiment, the voltage distribution is obtained using the measured voltage, the set value of each reactive power controller 21 is determined based on the voltage distribution, and transmitted to each reactive power controller 21. I did it. For this reason, even when there is a change in the voltage distribution, the probability that a set value corresponding to this change is set is increased, and non-uniformity in the amount of reactive power control among the reactive power controllers can be suppressed.

  The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

  1 upper system, 2 LRT, 3 SVR, 4-1, 4-2 pole transformer, 5-1, 5-2 consumer equipment, 6-1, 6-2 load, 7, 7-1, 7- 2 Power generation facilities, 10, 10a Central server, 11 Prediction unit, 12, 12a Simulation unit, 13 Settling value determination unit, 14, 23 Communication unit, 15, 24 Storage unit, 20 Power generation device, 21 Reactive power controller, 22 Power Control unit, 30-1, 30-2 measuring device.

Claims (16)

A voltage distribution calculation unit that calculates a voltage distribution of the power system for each combination of set values of a plurality of reactive power controllers that are installed by a consumer and connected to the power system;
A settling value determining unit that determines a settling value to be set in the reactive power controller based on the voltage distribution;
A communication unit that transmits the set value determined by the set value determination unit to the reactive power controller;
With
The power control apparatus, wherein the set value is determined and transmitted to the reactive power controller at at least two different times. A prediction unit for predicting a load and a power generation amount in the power system;
With
The voltage distribution calculation unit calculates a first voltage distribution of the power system based on the load and the power generation amount predicted by the prediction unit, and uses the calculated first voltage distribution as the plurality of reactive powers. The second voltage distribution is calculated by updating for each combination of controller settling values,
The power control apparatus according to claim 1, wherein the set value determination unit determines a set value to be set in the reactive power controller based on the second voltage distribution. A measurement information collection unit for obtaining a measurement result of the voltage in the power system;
With
The voltage distribution calculation unit calculates a first voltage distribution of the power system based on a measurement result acquired by the measurement information collection unit, and for each combination of set values of the plurality of reactive power controllers, Calculating the second voltage distribution by updating the first voltage distribution;
The power control apparatus according to claim 1, wherein the set value determination unit determines a set value to be set in the reactive power controller based on the second voltage distribution.   4. The power control apparatus according to claim 1, wherein a process of determining the set value and transmitting the determined value to the reactive power controller is periodically performed. 5. Receiving a control result from at least one of the plurality of reactive power controllers;
4. The method according to claim 1, wherein it is determined whether to perform a process of determining the set value and transmitting the determined value to the reactive power controller based on the control result. 5. Power control device.   4. The power control according to claim 1, wherein it is determined whether or not to execute a process of determining the set value and transmitting the determined value to the reactive power controller based on weather. 5. apparatus. The voltage distribution calculation unit calculates an evaluation value for evaluating equalization of a control amount between the reactive power controllers based on a voltage distribution for each combination of set values.
The power control apparatus according to any one of claims 1 to 6, wherein the set value determination unit determines a set value to be set in the reactive power controller based on the evaluation value.   The power evaluation apparatus according to claim 7, wherein the evaluation value includes a reactive power output amount of the reactive power controller.   The power evaluation apparatus according to claim 7, wherein the evaluation value includes a value obtained by dividing an amount of reactive power output from the reactive power controller by a rated value of the reactive power controller.   The power control apparatus according to claim 7, wherein the evaluation value includes an active power output suppression amount of the reactive power controller.   11. The set value is determined so that the reactive power controllers are grouped, and the reactive power controllers in the group use the same set value. The power control device described in 1. The settling value determining unit determines a response time of each of the plurality of reactive power controllers;
The power control apparatus according to claim 1, wherein the communication unit transmits information indicating the response time to the reactive power controller. A plurality of reactive power controllers installed by consumers and connected to the power system;
A power control device that controls the plurality of reactive power controllers;
With
The power control device
A voltage distribution calculation unit that calculates a voltage distribution of the power system for each combination of set values of the plurality of reactive power controllers;
A settling value determining unit that determines a settling value to be set in the reactive power controller based on the voltage distribution;
A communication unit that transmits the set value determined by the set value determination unit to the reactive power controller;
With
The power controller determines and transmits the settling value to the reactive power controller at at least two different times;
The reactive power controller controls the reactive power to be output in accordance with the set value received from the power control device. A reactive power controller installed by a consumer and connected to a power system,
In the power control apparatus that determines the set values of the plurality of reactive power controllers connected to the power system based on the voltage distribution of the power system, the communication unit that receives the set values determined at at least two different times When,
In accordance with the set value received by the communication unit, a power control unit that controls reactive power to be output;
A reactive power controller comprising: Receiving information indicating response time determined by the power control device from the power control device;
The reactive power controller according to claim 14, wherein the power control unit controls the reactive power to be output based on information indicating the response time. A power control method in a power control device for controlling a plurality of reactive power controllers installed by a consumer and connected to a power system,
A calculation step of calculating a voltage distribution of the power system for each combination of set values of the plurality of reactive power controllers;
A determining step for determining a set value to be set in the reactive power controller based on the voltage distribution;
A communication step of transmitting the settling value determined by the determining step to the reactive power controller;
Including
A power control method comprising: executing a calculation step, a determination step, and a communication step at least at two different times.

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