JP2019146416A - Setting value determination device, voltage regulating device, and setting value determination method - Google Patents

Abstract

To provide a setting value determination device, voltage regulating device including the same and setting value determination method, capable of autonomously determining a setting value to be set at an apparatus subjected to voltage regulation.SOLUTION: A setting value determination device (1), determining a setting value to be set at a voltage regulating apparatus (3) for regulating a voltage of a transmission and distribution line (110) of a power system (100), includes: an acquisition section for acquiring a physical amount relating to the transmission and distribution line (110) in a time-sequence manner; an analysis section for analyzing a frequency component of a physical amount for a predetermined time acquired by the acquisition section; and a determination section for determining the setting value on the basis of the frequency component analyzed by the analyzing section.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a settling value determining device that determines a settling value to be set in a voltage adjusting device that adjusts the voltage of a transmission / distribution line of a power system, a voltage adjusting device including the settling value determining device, and a settling value determining method.

  Various voltage regulators are installed on the power lines of the power system in order to properly maintain the system voltage. The voltage regulator generally performs autonomous control, and is required to be properly set by the installed system. On the other hand, against the background of global environmental problems in recent years, distributed power sources represented by photovoltaic power generation (PhotoVoltaic: hereinafter referred to as PV) have been widely introduced.

  In a distributed power source that generates power using natural energy, the amount of power generation may fluctuate greatly within a short time, and there is a concern that the frequency and amount of fluctuation of the system voltage may increase due to this. As described above, when the system voltage greatly fluctuates daily due to the distributed power source and the manner of fluctuations diversifies, the set value of the voltage regulator is not appropriate, and unnecessary voltage adjustment may occur frequently.

  When there is a problem with the set value of the voltage regulator, there is generally a situation where a person visits the site to change the set value. On the other hand, Patent Document 1 discloses a technique for performing settling that takes into account some degree of variation based on past measurement data when performing settling. Moreover, as disclosed in Patent Document 2, the master station controls the voltage regulator in real time by performing high-speed communication with the master station that monitors the entire distribution system installed in a substation or the like. Centralized control is also being studied.

JP 2012-182897 A Japanese Patent Laying-Open No. 2006-36252

  However, since it is necessary to process a huge amount of past data in order to perform settling taking into account voltage fluctuations disclosed in Patent Document 1, a large burden is required for data collection, organization, and analysis. For such a burden, it is basically impossible to cope with unexpected fluctuations that have never been seen in the past. Furthermore, when the voltage fluctuation is severe, there is a high possibility that an appropriate settling value cannot be calculated. On the other hand, in order to perform centralized control by the master station disclosed in Patent Document 2, it takes a great deal of cost to develop a communication infrastructure capable of high-speed communication, and the amount of processing required to grasp the entire range of the system Because of the enormous volume, the hurdles for introduction are very high. In addition, when communication with the master station is interrupted, there is a risk that control will fail.

  The present invention has been made in view of such circumstances, and a settling value determining device capable of autonomously determining a settling value to be set in a device that performs voltage adjustment, and a voltage adjustment including the settling value determining device. It is to provide a device and a settling value determination method.

  A settling value determining apparatus according to the present invention is a settling value determining apparatus that determines a settling value to be set in a voltage adjusting device that adjusts a voltage of a power transmission / distribution line in an electric power system. An acquisition unit that acquires serially; an analysis unit that analyzes a frequency component of a physical quantity for a predetermined time acquired by the acquisition unit; and a determination unit that determines the settling value based on the frequency component analyzed by the analysis unit; Is provided.

  A settling value determining method according to the present invention is a settling value determining method for determining a settling value to be set in a voltage adjusting device for adjusting a voltage of a power transmission / distribution line in an electric power system, wherein a physical quantity related to the transmission / distribution line is It includes a step of acquiring in series, a step of analyzing a frequency component of the acquired physical quantity for a predetermined time, and a step of determining the set value based on the analyzed frequency component.

  In the present invention, physical quantities such as the voltage of the transmission and distribution lines and the current flowing in the transmission and distribution lines are acquired in time series, and the frequency components are analyzed by performing a spectrum analysis of the physical quantities acquired in a time window of a predetermined time length. Then, based on the analyzed frequency component, a settling value to be set in the voltage adjusting device for adjusting the voltage of the transmission and distribution line is determined. Thereby, based on the frequency component of the physical quantity related to the power transmission and distribution line measured during the past predetermined time, it is determined whether the set value needs to be changed, and the set value is determined.

  The settling value determination device according to the present invention analyzes the frequency component every time shorter than the predetermined time.

  In the present invention, the spectrum analysis is repeated every time shorter than the time window length of the spectrum analysis. Thereby, even if the time window length is relatively long, the change of the frequency component is grasped for each relatively short time.

  The settling value determining apparatus according to the present invention further includes a calculating unit that calculates a predetermined feature amount based on the frequency component analyzed by the analyzing unit, and the determining unit is based on the feature amount calculated by the calculating unit. Determine the settling value.

  In the present invention, calculation is performed so as to extract a feature quantity that characteristically shows a change in the physical quantity from the frequency component of the physical quantity, and a settling value is determined based on the calculated feature quantity. Thus, the set value is changed when it is indicated from the feature quantity that there is a characteristic variation in the physical quantity.

  In the set value determination device according to the present invention, the feature amount is a ratio of a frequency component in a predetermined band to a frequency component analyzed by the analysis unit.

  In the present invention, the ratio of frequency components in a predetermined band to all frequency components analyzed by spectrum analysis is used as a feature amount. Thus, the settling value is changed when the proportion of the frequency component within the predetermined band indicates that there is a characteristic variation in the physical quantity.

  A settling value determining apparatus according to the present invention is a settling value determining apparatus that determines a settling value to be set in a voltage adjusting device that adjusts a voltage of a power transmission / distribution line in an electric power system. An acquisition unit that is acquired in series, a calculation unit that calculates a variance or standard deviation of a physical quantity for a predetermined time acquired by the acquisition unit, and the settling value is determined based on the variance or standard deviation calculated by the calculation unit And a determination unit.

  A settling value determining method according to the present invention is a settling value determining method for determining a settling value to be set in a voltage adjusting device for adjusting a voltage of a power transmission / distribution line in an electric power system, wherein a physical quantity related to the transmission / distribution line is A step of acquiring in series, a step of calculating a variance or standard deviation of the acquired physical quantity for a predetermined time, and a step of determining the set value based on the calculated variance or standard deviation.

  In the present invention, the physical quantity such as the voltage of the transmission and distribution line, the current flowing through the transmission and distribution line is acquired in time series, the variance or standard deviation of the acquired physical quantity for a predetermined time is calculated, the calculated variance or Based on the standard deviation, the settling value to be set in the voltage adjusting device for adjusting the voltage of the transmission and distribution lines is determined. Thereby, based on the dispersion | distribution or standard deviation of the physical quantity which concerns on the transmission / distribution electric wire measured in the past predetermined time, the necessity of a set value change is determined and a set value is determined.

  In the set value determination device according to the present invention, the calculation unit calculates a variance or a standard deviation every time shorter than the predetermined time.

  In the present invention, the calculation of the variance or the standard deviation is repeated every time shorter than the time required to acquire the physical quantity for which the variance or the standard deviation is calculated. Thereby, the measurement of the calculation target of the variance or the standard deviation is grasped at every relatively short time.

  In the settling value determining apparatus according to the present invention, the determining unit determines a settling value based on a comparison result between the feature amount or variance or standard deviation calculated by the calculating unit and a predetermined threshold value.

  In the present invention, since the set value is determined based on the result of comparing the predetermined threshold value with the feature value or variance or standard deviation calculated from the acquired physical quantity, the necessity of changing the set value is easily determined. .

  The set value determination device according to the present invention is based on a second acquisition unit that acquires information for a second time related to the adjustment of the voltage from the voltage adjustment device, and information acquired by the second acquisition unit. And a second calculation unit for calculating the threshold value.

  In the present invention, information relating to the adjustment of the voltage of the transmission / distribution line is acquired for the second time from the voltage adjusting device in which the set value is set, and a new threshold value is calculated based on the acquired information. Thereby, the threshold value is determined based on the information reflecting the setting result of the settling value in the past second time.

  In the settling value determining apparatus according to the present invention, the information includes information indicating a degree that the voltage of the transmission and distribution line deviates from a preset dead band region and a number of times that the voltage adjusting device has adjusted the voltage.

  In the present invention, the information acquired from the voltage adjustment device includes the degree to which the voltage of the transmission and distribution line deviates from the preset dead zone and the number of times the voltage adjustment device has adjusted the voltage. As a result, the threshold value is determined so that the frequency with which the voltage is adjusted by the voltage adjusting device and the degree of deviation from the dead zone are reduced in a balanced manner.

  The set value determination device according to the present invention is based on a third acquisition unit that acquires information for a third time related to the adjustment of the voltage from the voltage adjustment device, and information acquired by the third acquisition unit. And a learning unit for updating a relationship between the feature amount or variance or standard deviation calculated by the calculation unit and a set value to be determined by the determination unit.

  In the present invention, information relating to the voltage adjustment of the transmission and distribution lines is acquired for the third time from the voltage adjustment device in which the set value is set, and based on the acquired information, the feature amount or the variance or the standard deviation The relationship is learned by updating the relationship with the settling value and repeating this.

  The settling value determination device according to the present invention includes a third acquisition unit that acquires information for a third time relating to the adjustment of the voltage from the voltage adjustment device, and a fourth acquisition that acquires information indicating weather conditions. Based on the information acquired by the first acquisition unit, the third acquisition unit and the fourth acquisition unit, the physical quantity acquired by the acquisition unit, or the feature amount or variance or standard deviation calculated by the calculation unit. A learning unit that updates the value table; and a second determination unit that determines a feature quantity of the physical quantity based on the behavior value table updated by the learning unit, wherein the determination unit is calculated by the calculation unit Instead of the feature amount or variance or standard deviation, the set value is determined based on the feature amount determined by the second determination unit.

  In the present invention, the information for the third time concerning the voltage adjustment of the transmission / distribution line, the information indicating the weather condition, the physical quantity (or the calculated characteristic amount or variance or standard deviation) related to the transmission / distribution line, and the physical quantity The relationship is learned by updating the relationship with the feature amount and repeating this. And based on the learned relationship, the feature-value showing the characteristic of the physical quantity which concerns on a transmission / distribution electric wire is determined, and a settling value is determined based on the determined feature-value. Thereby, the feature quantity of the physical quantity related to the transmission / distribution line is predicted based on the learning result.

  In the settling value determination device according to the present invention, the information for the third time includes the degree that the voltage of the transmission and distribution line deviates from a preset dead band region and the number of times that the voltage adjusting device has adjusted the voltage. Contains information to indicate.

  In the present invention, the information acquired from the voltage adjustment device includes the degree to which the voltage of the transmission and distribution line deviates from the preset dead zone and the number of times the voltage adjustment device has adjusted the voltage. Thereby, the adjustment result of the voltage of a transmission / distribution electric wire is evaluated quantitatively.

  The settling value determination device according to the present invention further includes a third calculation unit that calculates an evaluation value for evaluating the voltage adjustment result based on the information acquired by the third acquisition unit, and the learning unit includes: The relationship or action value table is updated based on the evaluation value calculated by the third calculation unit.

  In the present invention, since the relationship between the feature value or the variance or the standard deviation and the settling value or the action value table is updated based on the evaluation value for evaluating the voltage adjustment result by the voltage adjusting device, the adjustment result is evaluated. The association or action value table is updated so that the value increases.

  In the set value determination device according to the present invention, the physical quantity is an effective value of a voltage on a power supply side or a load side with respect to the voltage adjusting device.

  In the present invention, since the voltage of the transmission / distribution line measured on either the power supply side or the load side of the voltage adjustment device is acquired as a physical quantity, the voltage fluctuation of the transmission / distribution line is suitably grasped.

  In the set value determining apparatus according to the present invention, the physical quantity is an effective value of a current passing through the transmission / distribution line on a power source side or a load side with respect to the voltage adjusting device.

  In the present invention, since the passing current of the transmission / distribution line measured on either the power supply side or the load side from the voltage adjustment device is acquired as a physical quantity, the load fluctuation of the transmission / distribution line is preferably grasped. .

  The voltage adjustment device according to the present invention includes the above-described set value determination device and a voltage adjustment device that adjusts the voltage of the transmission and distribution line based on the set value set by the set value determination device.

  In the present invention, a settling value determination device capable of autonomously determining a settling value to be set is applied to the voltage regulator.

  According to the present invention, it is possible to autonomously determine a settling value to be set for a device that performs voltage adjustment.

1 is a block diagram illustrating a configuration example of a voltage regulator according to a first embodiment. It is a graph which shows an example of transition of the feature-value which the voltage fluctuation of the power transmission / distribution electric wire by the side of a power supply and the set value determination apparatus which concerns on Embodiment 1 calculates. It is a flowchart which shows the process sequence of CPU which determines a set value with the set value determination apparatus which concerns on Embodiment 1, and sets it to a switching command part. It is a graph which shows transition of the electric power from a substation. It is a graph which shows transition of the active electric power which PV generates. It is a graph which shows the verification result by simulation comprehensively. It is a graph which shows the result of having simulated the voltage fluctuation of the power transmission and distribution line by the side of power supply, and the transition of the feature-value which a setting value determination apparatus calculates. It is a graph which shows the result of having simulated transition of tap change in the case of not having this function. It is a graph which shows the result of having simulated the transition of tap change in the case with this function. It is a graph which shows an example of the transition of the dispersion | distribution which the voltage fluctuation of the power transmission and distribution line by the side of a power supply and the set value determination apparatus which concerns on Embodiment 2 calculates. 10 is a flowchart illustrating a processing procedure of a CPU that calculates a threshold value in a set value determination device according to a third embodiment. 14 is a flowchart illustrating a processing procedure of a CPU that updates a relationship between a feature value or a variance and a settling value in a settling value determining device according to a fourth embodiment. It is a flowchart which shows the process sequence of CPU which determines a set value with the set value determination apparatus which concerns on Embodiment 4, and sets it to a switching command part. It is a block diagram which shows an example of a function structure of the set value determination apparatus which concerns on Embodiment 5. FIG.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.
(Embodiment 1)
FIG. 1 is a block diagram illustrating a configuration example of the voltage regulator according to the first embodiment of the present invention. A voltage regulator 10 as a so-called SVR (= Step Voltage Regulator) includes a transformer 120 with a tap that transforms the voltage of the transmission / distribution line 110 of the power system 100, and a tap changer 121 that switches a tap of the transformer 120. , And a control unit 2 that gives a tap switching command to the tap changer 121.

  When viewed from the transformer 120, the transmission / distribution line 110 on the opposite side (load side) to the power source side includes S_1, S_2, S_3... S_n−1, S_n. ... N loads of L_N-1 and L_N are connected. Each load is a collective load that represents an actual load in each section.

  The control unit 2 includes a CPU (Central Processing Unit) 21 for controlling the entire device. The CPU 21 stores a ROM (Read Only Memory) 22 for storing information such as a control program, and a RAM (for storing temporarily generated information). Random Access Memory) 23 and a timer 24 for measuring elapsed time and the like are connected to each other by a bus. The control unit 2 may include a microcomputer having a CPU. The CPU 21 or the microcomputer may be configured to execute a computer program having a predetermined processing procedure.

  The CPU 21 also switches to the tap switch 121 and the input unit 25 for acquiring the voltage of the transmission / distribution line 110 from the voltage detection unit 31 or acquiring the current of the transmission / distribution line 110 from the current detection unit 41. An output unit 26 for giving a command and an input unit 27 for acquiring a voltage on the secondary side of the transformer 120 from the voltage detection unit 51 are connected by a bus. Some or all of the voltage detection unit 31, the current detection unit 41, and the voltage detection unit 51 may be included in the control unit 2. The input unit 25 may be connected to a power detection unit (not shown) that detects an effective value of the power passing through the transmission and distribution line 110. Further, a communication unit 28 for communicating with a server (not shown) connected to the Internet 200 is bus-connected to the CPU 21, but the communication unit 28 is not used in the first embodiment.

  The voltage detection unit 31 detects the voltage of the transmission and distribution line 110 via the measurement transformer 30 that steps down the voltage, and gives the effective value of the detected voltage to the input unit 25. The current detection unit 41 detects a current via the current transformer 40 that transforms the current passing through the transmission / distribution line 110 at a predetermined ratio, and gives the effective value of the detected current to the input unit 25. The voltage detection unit 51 detects the voltage on the secondary side of the transformer 120 via the measurement transformer 50 and supplies the detected voltage to the input unit 27. The measurement transformer 30 is connected to the power transmission / distribution line 110 on the power supply side of the transformer 120, but may be connected to the load side. The current transformer 40 is connected to the transmission / distribution line 110 on the load side of the transformer 120, but may be connected to the power supply side.

  The control unit 2 realizes the function of a switching command unit that gives a tap switching command to the tap switcher 121 by software processing of the input unit 27, the output unit 26, and the CPU 21. What remove | excluded the switching command part containing the input part 27 and the output part 26 from the control part 2 is equivalent to the set value determination apparatus 1 which concerns on Embodiment 1 of this invention. The switching command unit including the input unit 27 and the output unit 26, the tap switch 121, and the transformer 120 correspond to the voltage adjusting device 3 that adjusts the voltage of the transmission and distribution line 110. Another control unit that realizes the function of the switching command unit may exist separately from the control unit 2.

  In the first embodiment, the function of the switching command unit is realized by software processing of the input unit 27, the output unit 26, and the CPU 21. However, instead of the switching command unit, a voltage drop generated in the transmission / distribution line 110 is realized. A line voltage drop compensator (LDC) that gives a tap switching command to the tap changer 121 based on the compensation voltage for compensation may be used. Since the configuration of the line voltage drop compensator is known, the illustration and detailed description thereof are omitted here.

  The control unit 2 of the settling value determination device 1 configured as described above receives the effective voltage, passing current, or passing power of the transmission and distribution line 110 from the voltage detection unit 31, the current detection unit 41, or the power detection unit (not shown). Values (hereinafter also referred to as physical quantities) are acquired in time series, for example, every second. Further, the control unit 2 analyzes the frequency component of the acquired physical quantity, and determines a set value to be set in the switching command unit or the line voltage drop compensator based on the analysis result. In the following description, it is assumed that the voltage of the transmission / distribution line 110 is acquired from the voltage detection unit 31 as a physical quantity.

  The switching instruction unit deviates from the so-called dead zone where the voltage of the secondary side of the transformer 120 obtained from the voltage detection unit 51 is set as the set value, exceeding the operation time limit set as the set value. If so, issue a tap switching command. The width of the dead zone is set as a percentage of the reference voltage. That is, the set values set in the switching command unit by the set value determining apparatus 1 are, for example, the width (% value) of the dead zone and the operation time limit (seconds). In addition to the operation time period set as a settling value, whether or not tap switching is necessary is determined by the operation time period, by an integration method (time × dead zone deviation amount = integral value (Vs value: volts / second)), or A value indicating whether to make a determination based on the moving average of the acquired voltage may be set as a settling value.

  Specifically, the switching command unit issues a switching command to lower the voltage of the transmission / distribution line 110 when the state where the voltage on the secondary side of the transformer 120 is higher than the upper limit value of the dead zone continues for the operation time period or longer. . In addition, when the voltage on the secondary side of the transformer 120 is lower than the lower limit value of the dead zone, the switching command unit issues a switching command to increase the voltage of the power transmission and distribution line 110 when the state continues for the operation time period or longer. In this case, the longer the operation time limit and the wider the dead zone region, the more the tap switching frequency of the transformer 120 can be suppressed. However, the voltage of the transmission and distribution line 110 may deviate from the so-called voltage management width. Becomes higher. On the other hand, as the operation time period is shorter and the predetermined width of the dead zone is narrower, the voltage of the transmission / distribution line 110 can be suppressed from deviating from the voltage management range, but the tap switching frequency increases.

  On the other hand, when a line voltage drop compensator is used, the line voltage drop compensator is connected to a series impedance of a resistance component R (or% R) and a reactance component X (or% X) set as a set value, for example, current detection. Based on the product of the passing current on the secondary side of the transformer 120 acquired from the unit 41, a voltage drop to a so-called voltage drop center point is calculated, and an ultimate voltage at the voltage drop center point is assumed. Then, the line voltage drop compensator determines the transmission voltage of the transformer 120 so that the assumed reached voltage becomes the reference voltage, and the tap voltage is set so that the secondary voltage of the transformer 120 becomes this transmission voltage. Issue a switching command. That is, the set values set by the set value determining apparatus 1 in the line voltage drop compensator are, for example, the values of the resistance component R and the reactance component X. In general, in addition to these values, the width of the dead zone is set as a set value. An operation time limit may be further set.

  Next, frequency component analysis will be described. The settling value determination device 1 calculates the amplitude spectrum or the power spectrum by performing spectrum analysis, for example, by Fast Fourier Transform (FFT) for the voltage of the transmission and distribution line 110 acquired from the voltage detection unit 31. Analyze frequency components. For example, when the sampling frequency is fs and the number of samples is N (a power of 2), the time window length is N / fs (corresponding to a predetermined time), and a data set in this time domain is a frequency domain data set. Is converted to In this case, the frequency resolution is fs / N.

  When analyzing the frequency component, if it is estimated that the resolution (fs / N) of the frequency component included in the voltage of the transmission / distribution line 110 needs to be about 0.5 mHz, for example, the voltage is sampled every second ( fs = 1 Hz) and the number of samplings (N) must be about 2048. In this case, the time window length is 2048 seconds. On the other hand, since it is necessary to monitor the fluctuation of the frequency component approximately every 5 minutes in order to determine the settling value, in the first embodiment, the fast Fourier transform is performed every 5 minutes while shifting the time window by 5 minutes. To do.

  In this way, by analyzing the frequency component of the voltage of the transmission / distribution line 110 at regular intervals, when there is a voltage fluctuation that adversely affects the operation of the voltage regulator 10, a specification that includes a component with a relatively short period is included. It is found that the ratio of frequency components in the band (corresponding to the predetermined band) fluctuates. The voltage fluctuation which has a bad influence here means the voltage fluctuation which has a period comparable as the operation | movement time limit set to a switching command part, for example. When such a voltage fluctuation occurs, an unnecessary operation in which the voltage regulator 10 repeatedly switches the tap up and down within a short time occurs, resulting in a further voltage fluctuation in the transmission and distribution line 110. The unnecessary operation referred to here is different from hunting due to competition with other voltage regulators connected to the power transmission and distribution line 110.

  Therefore, the ratio of the sum of the amplitudes or powers of the frequency components in a specific band to the sum of the amplitudes or powers of all the analyzed frequency components is calculated as a feature amount, and the calculated feature amount is compared with a predetermined threshold value. Thus, the set value is determined to be changed. As a result, the set value can be changed in a timely manner by capturing a sign that an unnecessary operation occurs. As described above, in the first embodiment, since the fast Fourier transform is performed every 5 minutes, the feature amount is also calculated every 5 minutes.

  Specifically, for example, a ratio of frequency components in a band including a component having a period of about 1 to 5 minutes (converted to a frequency of 16 mHz to 3.3 mHz) is calculated as a feature amount every 5 minutes. The settling value is determined to be a predetermined first settling value or a second settling value depending on whether the feature amount is smaller or larger than a predetermined threshold. When the feature amount exceeds a second threshold value that is greater than the threshold value, the set value may be determined as the third set value. The first set value, the second set value, and the third set value here are a set of one or more set values.

  FIG. 2 is a graph showing an example of voltage fluctuation of the power transmission / distribution line 110 on the power source side and a transition of the characteristic amount calculated by the set value determination device 1 according to the first embodiment. The horizontal axis of the figure represents the time [hour], and the vertical axis represents the voltage [kV] or the size [%] of the feature amount of the transmission / distribution line 110. The thick solid line on the upper side of FIG. 2 shows the fluctuation of the voltage of the transmission and distribution line 110 acquired every second, and the thin thin line on the lower side shows the transition of the feature amount updated every 5 minutes. Yes. According to FIG. 2, unnecessary operations are intermittently generated from around 7:30 to around 17:00, and the feature amount during this period exceeds the 10% line indicated by the broken line in the figure. It seems that there are many.

  Therefore, it is considered that the voltage fluctuation at the time when the unnecessary operation starts can be captured by setting the threshold value of the feature amount for determining whether or not to decide to change the settling value to 10%, for example. . When the feature amount is larger than 10%, in order to suppress the tap switching frequency, the second settling value is selectively determined as a settling value having a relatively wide dead zone and a relatively long operation time. Conversely, when the feature amount is smaller than 10%, in order to increase the tap switching frequency, the first set value is selectively determined as a set value having a relatively narrow dead zone area and a relatively short operation time limit. Instead of selecting and determining a set value, a set value corresponding to the size of the feature amount may be calculated and determined.

  Next, operation | movement of the control part 2 of the set value determination apparatus 1 which concerns on Embodiment 1 comprised in this way is demonstrated using the flowchart which shows it. The processing shown below is executed by the CPU 21 in accordance with a control program stored in advance in the ROM 22. FIG. 3 is a flowchart illustrating a processing procedure of the CPU 21 that determines a set value in the set value determination apparatus 1 according to the first embodiment and sets the set value in the switching command unit. Since the operation of issuing a tap switching command based on the settling value is known, the description of the flowchart showing the processing procedure of the CPU 21 related to the switching command unit is omitted.

  The process of FIG. 3 is started every second after the CPU 21 is initialized. The RAM 23 has 2048 points or more of ring buffers, and writing to the ring buffer is executed at the address indicated by the pointer. K in the figure is a counter for counting the number of times corresponding to 5 minutes (300 seconds), and the initial value is 2048. In the initial state, the fact that the first set value (the set value selected when the feature amount is smaller than the threshold value) is being selected is stored as the set value.

  When the process of FIG. 3 is activated, the CPU 21 acquires the voltage of the transmission and distribution line 110 from the voltage detection unit 31 (S11: corresponding to the acquisition unit), and stores the acquired voltage at the address indicated by the pointer (S12). ). Next, the CPU 21 increments the pointer by 1 for storing the next voltage (S13), further decrements k by 1 (S14), and determines whether k is 0 (S15). .

  When k becomes 0 (S15: YES), that is, when the voltage for 2048 points is stored in the ring buffer for the first time after initialization, or when 300 seconds have passed since the previous FFT, the CPU 21 determines that 300 seconds. In order to execute FFT later, 300 is substituted for k (S16). Next, the CPU 21 performs FFT on the voltages for 2048 points before the pointer (S17: corresponding to the analysis unit), and calculates the characteristic amount of the analyzed frequency component (S18: corresponding to the calculation unit).

  Thereafter, the CPU 21 determines whether or not the fact that the first set value is being selected is stored (S19). If the first set value is being selected (S19: YES), that is, in the previous determination, When the feature amount is smaller than the threshold value, it is determined whether or not the calculated feature amount is larger than a predetermined threshold value (S20). When the feature amount is not larger than the threshold value (S20: NO), the CPU 21 ends the process of FIG. 3 without newly determining a set value.

  On the other hand, when the calculated feature amount is larger than the threshold value (S20: YES), the CPU 21 determines the set value as the second set value (S21: equivalent to the determination unit), and sets the determined set value in the switching command unit. (S22). Then, the CPU 21 stores that the second set value is being selected instead of selecting the first set value (S23), and ends the process of FIG.

  In step S19, if the first set value is not selected (S19: NO) and the second set value is being selected, that is, if the feature amount is larger than the threshold value in the previous determination, the CPU 21 calculates It is determined whether the determined feature amount is smaller than a threshold value (S24). When the feature amount is not smaller than the threshold value (S24: NO), the CPU 21 ends the process of FIG. 3 without newly determining a set value.

  On the other hand, when the calculated feature amount is smaller than the threshold value (S24: YES), the CPU 21 determines the set value as the first set value (S25: equivalent to the determination unit), and sets the determined set value in the switching command unit. (S26). Then, the CPU 21 stores that the first set value is being selected instead of selecting the second set value (S27), and ends the process of FIG.

  In the first embodiment, the effective value of the voltage is acquired as a physical quantity related to the transmission and distribution line 110, and the settling value is determined based on the acquired effective value of the voltage. Instead, the effective value of the passing current of the transmission / distribution line 110 or the active power or reactive power of the passing power may be acquired. Even when these currents or powers are acquired, it is possible to determine to change the settling value at an appropriate timing.

(simulation)
Hereinafter, the case where the set value determination device 1 in the voltage adjustment device 10 according to the first embodiment determines to change the set value according to the voltage of the transmission and distribution line 110 and the case where the set value is not changed are compared by simulation. The verified result will be described. The model of the power system 100 used for the verification conforms to FIG. Specifically, the voltage regulator 10 was connected to a point where the length of the transmission line 110 from the substation (not shown) was 3 km, and the length of the load-side transmission and distribution line 110 was 4 km. The load side section was equally divided into five, and the loads L_1, L_2, L_3, L_4, and L_5 were equally distributed in the sections S_1, S_2, S_3, S_4, and S_5. PV is linked to the end side of the section S_5.

  The transmission voltage from the substation is constant at 6600 V at 50 Hz. FIG. 4 is a graph showing the transition of power from the substation, and FIG. 5 is a graph showing the transition of active power generated by the PV. 4 and 5, the horizontal axis represents time [hour], and the vertical axis represents power [MW]. The solid line in FIG. 4 indicates active power, and the wavy line indicates reactive power. In FIG. 4, the active power and the reactive power increase rapidly from about 8 o'clock and gradually decrease from about 17:00 to about 22:00. In FIG. 5, the active power increases and decreases in a bell shape between about 6 o'clock and about 18 o'clock. However, the rate at which the power fluctuates within a short time is relatively large.

The specifications and settling conditions of the voltage regulator 10 are as follows. The voltage management width was 6750V for the upper limit and 6300V for the lower limit.
(A) Tap width: 100V
(B) Number of tap stages: 9 stages (1 step through, 4 steps for boosting and 4 steps for stepping down)
(C) Reference voltage: 6600V
(D) Dead zone width with respect to the reference voltage: 1% (± 66V)
(E) Operation time limit: 45 seconds

The operating conditions of the set value determination device 1 are as follows.
(F) Voltage measurement interval of transmission / distribution line 110: 1 second (g) FFT time window length: 2048 seconds (h) FFT update interval (calculation cycle): 300 seconds (i) Feature amount: 1 minute cycle Ratio of frequency component to ˜5 minutes (j) Threshold value to be compared with feature amount: 10% and 20%
(K) Setting value determined to be changed Operation time limit when feature amount is larger than 10%: 120 seconds Operation time limit when feature amount is larger than 20%: 180 seconds

  In this verification, the transition of the voltage, feature amount, and tap position of the transmission / distribution line 110 during a period of 86400 seconds from 0:00 to 24:00 was sampled and simulated every 1 ms. FIG. 6 is a chart comprehensively showing the verification results by simulation. “With this function” means that the set value is determined to be changed according to the voltage of the transmission / distribution line 110, and “Without this function” means when the set value is not changed (the same applies hereinafter). ).

  The “deviation from the voltage management range” in the chart is the sum of the deviations (V) of the voltage simulated every 1 second or 30 minutes in each of the sections S_1, S_2, S_3, S_4, and S_5 for 24 hours. An average deviation amount per minute obtained by dividing the sum by 1440 is represented. Of these, the “one-second value” is an average value per minute of the result of the total sum of the above deviation amounts being 86,400 times in 24 hours. In addition, “30 minutes average value” means that the sum of the above deviation amounts is accumulated 48 times in 24 hours for the voltage obtained by averaging the voltage simulated every second for 30 minutes. Is the average value. The “number of operations” is the number of tap switching during 24 hours. The “maximum fluctuation range” is the largest difference among the differences between the maximum voltage value and the minimum voltage value in each of the sections S_1, S_2, S_3, S_4, and S_5. “Settling update” is the number of times the settling value is determined and set in the switching command section.

  FIG. 6 shows that the deviation amount of the average value for 30 minutes is 0 regardless of the presence or absence of this function. It can also be seen that there is no significant difference in the maximum fluctuation range. On the other hand, the number of operations is 53 for the case without this function, 39 for the case with this function, and is reduced by 14 times. Although the deviation amount of the 1 second value is slightly increased in the case of this function, it can be said that the difference is slight considering that the tap width is 100V. That is, it was shown that only the number of operations can be reduced while maintaining the deviation amount and the fluctuation range.

  Next, the validity of the threshold value to be compared with the feature amount will be described. FIG. 7 is a graph showing a result of simulating the voltage fluctuation of the power transmission / distribution line 110 on the power source side and the transition of the characteristic amount calculated by the set value determination device 1. The horizontal axis of the figure represents the time [hour], and the vertical axis represents the voltage [kV] or the size [%] of the feature amount of the transmission / distribution line 110. The thick solid line on the upper side of FIG. 7 shows the fluctuation of the voltage of the transmission and distribution line 110 acquired every second, and the thin thin line on the lower side shows the transition of the feature amount updated every 5 minutes. Yes.

  According to FIG. 7, the short period fluctuations in the voltage of the power transmission / distribution line 110 on the power source side are the time zone from about 1 o'clock to about 6 o'clock and the time from about 10 o'clock to about 17 o'clock. It is a belt. In these time zones, there is a difference in the amplitude of the voltage fluctuation, but in the same time zone, the frequency at which the feature amount becomes larger than the threshold of 10% (see the broken line) is increasing, and 10% is one reasonable It is confirmed that it is a threshold value.

  Finally, the effect of reducing the number of tap operations will be described. FIG. 8 is a graph showing the result of simulating the transition of tap switching in the case without this function, and FIG. 9 is a graph showing the result of simulating the transition of tap switching in the case with this function. The horizontal axis of these figures represents time [hour], and the vertical axis represents the tap position. Although the illustration of the simulation result is omitted, the frequency of deviation from the voltage management range and the magnitude of the deviation were not significantly different depending on the presence or absence of this function. Similarly, the transition of the voltage obtained by averaging the voltage simulated every second for 30 minutes was not greatly different in the tendency of fluctuation.

  According to FIG. 8, it can be seen that in the absence of this function, the tap switching frequency increases between about 10 o'clock and about 15 o'clock, and an unnecessary operation occurs in many periods. On the other hand, according to FIG. 9, it can be seen that when this function is provided, tap switching is suppressed during a period in which an unnecessary operation has occurred.

  From the above simulation results, it was found that if this function is applied, unnecessary tap switching can be suppressed while maintaining the function of adjusting the voltage of the transmission and distribution line 110. That is, it has been found that this function can autonomously determine the timing at which a settling change is necessary from information obtained by measuring the physical quantity related to the transmission / distribution line 110, and can automatically change it to an appropriate settling value.

  As described above, according to the first embodiment, the physical quantity such as the voltage of the transmission / distribution line 110 and the current flowing through the transmission / distribution line 110 is acquired every second, and the spectrum obtained by FFT with respect to the physical quantity acquired in the 2048-second time window. An analysis is performed to analyze the frequency component, and a settling value to be set in the switching command unit is determined based on the analyzed frequency component. Therefore, based on the frequency component of the physical quantity related to the power transmission and distribution line 110 measured during the past predetermined time, it is determined whether or not it is necessary to change the set value, and the set value to be set in the switching command unit is autonomously determined. It becomes possible to do. For example, even when the voltage fluctuation of the transmission / distribution line 110 is diversified as the introduction of the distributed power source such as PV proceeds, the voltage adjustment of the transmission / distribution line 110 can be flexibly performed.

  Further, according to the first embodiment, the spectrum analysis is repeated every 5 minutes, which is shorter than 2048 seconds, which is the time window length of the spectrum analysis. Therefore, even when the time window length is set to a relatively long time of 2048 seconds, it is possible to grasp a change in frequency component every relatively short time of 5 minutes.

  Furthermore, according to the first embodiment, a feature value that characteristically indicates a change in physical quantity is calculated from the frequency component of the physical quantity, and a settling value is selectively determined based on the calculated feature quantity. Accordingly, the set value can be changed when the characteristic amount indicates that there is a characteristic variation in the physical quantity related to the transmission and distribution line 110.

  Further, according to the first embodiment, the ratio of frequency components within a specific band (for example, within a band including a component with a period of about 1 to 5 minutes) with respect to all frequency components analyzed by spectrum analysis is used as a feature amount. . Therefore, the set value can be changed when the ratio of frequency components in a specific band indicates that there is a characteristic variation in the physical quantity related to the transmission and distribution line 110.

(Embodiment 2)
While the first embodiment is a mode in which a set value is determined based on a feature value extracted from the frequency component of the acquired physical quantity, the second embodiment has a set value based on the variance or standard deviation of the acquired physical quantity. It is a form to decide. The variance or standard deviation represents the degree of deviation from the average value, and can be said to be one of the indicators suitable for grasping the fluctuation of the physical quantity. In the following description, it is assumed that the variance is calculated. However, in order to match the physical quantity to be calculated with the dimension, a standard deviation may be calculated instead of the variance.

  Since the block configuration of the voltage regulator according to the second embodiment is the same as that of the voltage regulator 10 according to the first embodiment, the illustration thereof is omitted, and the portions corresponding to the first embodiment are denoted by the same reference numerals. The description is omitted.

  In the second embodiment, for the effective value of the voltage of the transmission / distribution line 110 acquired every second, for example, the variance of the voltage (corresponding to a physical quantity for a predetermined time) acquired in 1800 seconds is calculated every five minutes. The settling value is determined to be a predetermined first settling value or a second settling value depending on whether the variance is smaller or larger than a predetermined threshold. As in the first embodiment, instead of acquiring the effective value of the voltage, the effective value of the passing current of the transmission and distribution line 110, or the active power or reactive power of the passing power may be acquired.

  FIG. 10 is a graph showing an example of the voltage fluctuation of the power transmission / distribution line 110 on the power source side and the transition of dispersion calculated by the set value determination device 1 according to the second embodiment. The horizontal axis of the figure represents the time [hour], and the vertical axis represents the voltage [kV] or the dispersion value of the transmission and distribution line 110. The thick solid line on the upper side of FIG. 10 shows the fluctuation of the voltage of the transmission / distribution line 110 acquired every second, and the thin thin line on the lower side shows the transition of the variance updated every 5 minutes. .

  According to FIG. 10, unnecessary operations occur intermittently from around 8 o'clock to around 16:30, and the variance during this period often exceeds a threshold of about 0.3 to 0.5. I can see. Note that the case where the variance is 0.3 corresponds to, for example, a case where the voltage acquired for 1800 seconds, which is the calculation target of the variance, varies linearly with the passage of time from minus 1% of 6600 V to plus 1%. To do.

  Therefore, it is considered that the voltage fluctuation at the time when the unnecessary operation starts can be captured by setting the dispersion threshold for determining whether or not to determine the set value to be changed to, for example, 0.3. . When the variance is larger than 0.3, the above-described second set value is selectively determined as a set value in order to suppress the tap switching frequency. On the other hand, when the variance is smaller than 0.3, the above-described first set value is selectively determined as the set value in order to increase the tap switching frequency. Instead of selecting and determining a settling value, a settling value corresponding to the magnitude of the variance may be calculated and determined.

  The flowchart showing the operation of the control unit 2 of the settling value determining apparatus 1 according to the second embodiment is the same as that shown in FIG. 3 of the first embodiment, and will be described with reference to FIG. In the second embodiment, the variance is calculated for the voltage of 1800 points before the pointer in steps S17 and S18 of FIG. In step S20, it is determined whether the variance is larger than the threshold value, and in step S24, it is determined whether the variance is smaller than the threshold value. Note that the initial value of k is 1800. The processing contents of the other steps are as shown in FIG. By the processing shown in the flowchart, the variance of the voltage acquired in 1800 seconds is calculated every 5 minutes, and the set value is determined based on the calculated variance.

  As described above, according to the second embodiment, the physical quantity such as the voltage of the transmission / distribution line 110 and the current flowing through the transmission / distribution line 110 is acquired every second, and the variance of the physical quantity acquired during 1800 seconds is calculated. Based on the dispersion, the settling value to be set in the switching command unit is determined. Therefore, it is determined whether or not the set value needs to be changed based on the dispersion of the physical quantity related to the transmission / distribution line 110 measured during the past predetermined time, and the set value to be set in the switching command unit is autonomously determined. It becomes possible.

  Further, according to the second embodiment, the calculation of dispersion is repeated every 5 minutes, which is shorter than 1800 seconds required to acquire a physical quantity to be calculated for one dispersion. Therefore, even when the dispersion calculation range is set to a relatively long time of 1800 seconds, it is possible to grasp the change in dispersion every relatively short time of 5 minutes.

  Furthermore, according to the first and second embodiments, since the set value is determined based on the result of comparing the feature value or variance or standard deviation calculated from the acquired physical quantity with a predetermined threshold value, it is easy to determine whether the set value needs to be changed. Can be determined.

  Furthermore, according to the first and second embodiments, since the voltage of the transmission / distribution line 110 measured on either the power supply side or the load side from the voltage regulator 3 is acquired as a physical quantity, the voltage fluctuation of the transmission / distribution line 110 is obtained. Can be grasped suitably.

  Furthermore, according to the first and second embodiments, the passing current of the transmission / distribution line 110 measured on either the power supply side or the load side of the voltage regulator 3 can be acquired as a physical quantity. It is possible to appropriately grasp the load fluctuation.

(Embodiment 3)
While each of the first and second embodiments is a mode in which a person determines in advance a threshold value to be compared with the feature amount and the variance, the third embodiment is a mode in which the set value determination device 1 calculates the threshold value. . Specifically, a new threshold value is calculated by applying the operation result of the voltage regulator 10 in which the set value determined by the set value determining device 1 based on the comparison result with the threshold value is set to a predetermined formula.

  Since the block configuration of the voltage regulator according to the third embodiment is the same as that of the voltage regulator 10 according to the first embodiment, the illustration thereof is omitted, and the portions corresponding to the first embodiment are denoted by the same reference numerals. The description is omitted.

  In the third embodiment, based on the operation result of the voltage regulator 10, the specific violation amount is represented by an objective function F (x) represented by the following equation (1), and the absolute value of this F (x) should be minimized. The new threshold value Th ′ is calculated by the following formulas (2) and (3) using the current threshold value Th.

F (x) = Vout (p) + (Ntap_th−Ntap) (1)
Th ′ = Th + αVout (p) + β (Ntap_th−Ntap) (2)
lower ≦ Th ′ ≦ upper (3)
However,
Vout (p): Deviation amount from the dead zone area (corresponding to the degree of departure from the dead zone area)
Ntap_th: prescribed number of tap switchings Ntap: number of taps switching in voltage regulator 10 (corresponding to the number of times of voltage adjustment)
α, β: coefficient for weighting lower: lower limit value of threshold upper: upper limit value of threshold

  Note that Vout (p) is a deviation amount from the dead band region related to the voltage on the secondary side of the transformer 120, but is a deviation in each section S_1, S_2, S_3... S_n-1, S_n in FIG. When the amount can be acquired, the sum of the deviation amounts in these sections may be used. The deviation amount Vout (p) and the tap switching frequency Ntap are stored in the RAM 23 for a predetermined number of days or more by the voltage adjusting device 3 and can be acquired by the settling value determination device 1 in a timely manner.

  For example, when α is set to a positive number and β is set to a negative number in Equation (2), when the amount of deviation from the dead zone is relatively small and the number of tap switching increases from the specified number of times, Th ′ lowered from the threshold Th is set as a new threshold. This makes it easier to determine the second settling value (see Embodiment 1) in which the dead zone region is relatively wide and the operation time period is relatively long. On the contrary, when the deviation amount from the dead zone increases or when the number of tap switching decreases from the prescribed number, Th ′ raised from the current threshold Th is set as a new threshold Th ′. This makes it easier to determine the first settling value in which the dead zone width is relatively narrow and the operation time period is relatively short.

  Next, operation | movement of the control part 2 of the set value determination apparatus 1 which concerns on Embodiment 3 comprised in this way is demonstrated using the flowchart which shows it. FIG. 11 is a flowchart illustrating a processing procedure of the CPU 21 that calculates a threshold value in the set value determination device 1 according to the third embodiment. The process of FIG. 11 is started every day, for example, but is not limited thereto.

  When the processing shown in FIG. 11 is activated, the CPU 21 acquires the deviation amount Vout (p) from the dead zone for a predetermined number of days (corresponding to the second time) from the RAM 23 (S31: second acquisition unit). Further, the tap switching frequency N tap for a predetermined number of days is acquired from the RAM 23 (S32: corresponding to the second acquisition unit). Next, the CPU 21 calculates a new threshold Th ′ by applying the acquired deviation amount and number of times to the equation (2) (S33: corresponding to the second calculation unit).

  Thereafter, the CPU 21 determines whether or not the calculated new threshold is smaller than the lower limit value lower of the threshold (S34), and if it is smaller (S34: YES), the new threshold is limited to the lower limit (S35). 11 processing is ended.

  When the calculated new threshold value is not smaller than the lower limit value in step S34 (S34: NO), the CPU 21 determines whether or not the calculated new threshold value is larger than the upper limit value upper of the threshold value (S36). (S36: YES), the new threshold is limited to the upper limit (S37), and the process of FIG. 11 is terminated. If the new threshold value is not larger than the upper limit value upper of the threshold value (S36: NO), the process of FIG. 11 is terminated without limiting the threshold value.

  As described above, according to the third embodiment, information relating to the adjustment of the voltage of the transmission and distribution line 110 is acquired for a predetermined number of days from the voltage adjustment device 3 in which the set value is set via the RAM 23, and based on the acquired information. To calculate a new threshold Th ′. Therefore, a new threshold value can be determined based on information reflecting the setting result of the set value within the past predetermined number of days.

  In addition, according to the third embodiment, the information acquired from the voltage adjustment device 3 via the RAM 23 switches the tap between the voltage adjustment device 3 and the degree to which the voltage of the transmission and distribution line 110 has deviated from the preset dead band region. And the number of times the voltage was adjusted. Therefore, the threshold value can be determined so as to reduce the frequency with which the voltage adjusting device 3 adjusts the voltage and the degree of deviation from the dead zone region in a balanced manner.

  Furthermore, according to the third embodiment, the settling value determination device 1 that can autonomously determine the settling value to be set can be applied to the voltage adjustment device 10.

(Embodiment 4)
While the first or second embodiment is a mode in which a set value is determined based on a result of comparing the calculated feature value or variance with a predetermined threshold, the fourth embodiment is determined as a calculated feature value or variance. This is a form in which the relationship with the settling value to be updated is updated by machine learning, and the settling value is determined by applying the calculated feature amount or variance to the learned relationship. Since the block configuration of the voltage regulator according to the fourth embodiment is the same as that of the voltage regulator 10 according to the first embodiment, portions corresponding to those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. In the following, standard deviation may be used instead of variance.

  In the first to third embodiments, a preset set value is used, but the set value may not match (cannot be controlled correctly) depending on the installed system conditions. Therefore, it is also conceivable to determine a settling value that matches the system conditions (can be controlled correctly) by performing learning that takes into account the feature quantity that is a component that adversely affects control in the installed system state.

  In the fourth embodiment, an example in which a settling value is determined by reinforcement learning included in machine learning will be described below. Reinforcement learning is to learn an action that maximizes value through trial and error, but machine learning by the settling value determination device 1 is not limited to reinforcement learning.

  In this reinforcement learning, a relationship between the calculated feature value or variance and a set value to be determined as an action is learned as an action value function, and this relation is stored in a table, for example. In learning, the set value determination device 1 acquires information related to voltage adjustment of the transmission and distribution line 110 and observes the state of voltage adjustment. The information related to voltage adjustment is, for example, the deviation amount Vout (p) from the dead zone shown on the right side of the expression (1) of the third embodiment and the number Ntap of tap switching. It is assumed that these pieces of information can be acquired in a timely manner from the voltage regulator 3 described above as information for a predetermined time (corresponding to the third time).

  Next, the set value determination device 1 calculates an evaluation value (corresponding to a so-called reward in reinforcement learning) for evaluating the adjustment result of the voltage of the transmission and distribution line 110 based on the amount of the state to be observed. For example, a positive evaluation value is calculated when the deviation amount Vout (p) is smaller than a prescribed deviation amount, and a negative evaluation value is calculated when it is larger than the prescribed deviation amount. Further, for example, a positive evaluation value is calculated when the tap switching frequency Ntap is smaller than the specified number Ntap_th, and a negative evaluation value is calculated when it is larger than the specified number Ntap_th. The calculated evaluation values are integrated.

  Next, the set value determination device 1 updates the table indicating the above-described relationship based on the calculated and integrated evaluation values. For example, the set value associated with the feature amount or variance calculated immediately before acquiring the state relating to the voltage adjustment of the transmission and distribution line 110 is updated.

  Specifically, when the evaluation value is positive, in order to increase the tap switching sensitivity, the dead zone area is updated to a set value that narrows the width of the dead zone and shortens the operation time limit. On the contrary, when the evaluation value is negative, in order to make the sensitivity of tap switching more dull, it is updated to a set value that makes the dead zone region wider and the operation time longer. By repeating such an update, the relationship between the feature value or variance and the settling value is learned so that the evaluation value of the adjustment result of the voltage of the transmission and distribution line 110 based on the determined settling value becomes larger. .

  Next, operation | movement of the control part 2 of the set value determination apparatus 1 which concerns on Embodiment 4 comprised in this way is demonstrated using the flowchart which shows it. FIG. 12 is a flowchart showing a processing procedure of the CPU 21 for updating the relationship between the feature value or the variance and the settling value in the settling value determining apparatus 1 according to the fourth embodiment, and FIG. It is a flowchart which shows the process sequence of CPU21 which determines a set value in the apparatus 1 and sets to a switching command part.

  The process of FIG. 12 is started every 5 minutes, for example, when a set value is determined and set in the switching command unit, but is not limited thereto. The process of FIG. 13 is started every second after the CPU 21 is initialized. The ring buffer, pointer, initial value of k, and the like used in this processing are the same as those in the flowchart shown in FIG.

  When the process shown in FIG. 12 is started, the CPU 21 acquires the deviation amount Vout (p) from the dead zone region for a predetermined time (corresponding to the third time) from the voltage adjusting device 3 (S41: No. 1). 3), and the tap switching frequency Ntap for a predetermined time is acquired from the voltage regulator 3 (S42: equivalent to the third acquisition unit). Then, the CPU 21 calculates an evaluation value 1 in accordance with the acquired amount of deviation (S43: equivalent to a third calculation unit). The predetermined time here is preferably sufficiently longer than 5 minutes, which is the cycle in which the processing of FIG. 12 is started.

  Next, the CPU 21 compares the acquired number of tap switching times with the specified number of switching times (S44), and calculates an evaluation value 2 according to the comparison result (S45: equivalent to a third calculating unit). Thereafter, the CPU 21 adds (integrates) the evaluation value 1 and the evaluation value 2 to obtain an evaluation value of the voltage adjustment result (S46: equivalent to the third calculation unit), and based on the integrated evaluation value, the feature amount Alternatively, the relationship between the variance and the settling value is updated (S47: corresponding to the learning unit), and the processing in FIG.

  Moving to FIG. 13, the processing from step S51 to S58 shown in FIG. 13 is the same as the processing from step S11 to S18 shown in FIG. When the process of FIG. 13 is activated and the feature amount is calculated (S58), the CPU 21 determines a settling value based on the relationship learned in the process shown in the flowchart of FIG. 12 (S59), and the settling value thus determined Is set in the switching command section (S60), and the processing of FIG. In steps S57 and S58, the variance may be calculated instead of the feature amount. In this case, as in the case of quoting FIG. 3 in the second embodiment, for example, the variance is calculated for the voltage for 1800 points before the pointer. The initial value of k is 1800.

  Instead of the processing shown in the flowchart of FIG. 12, the state relating to the voltage adjustment of the transmission / distribution line 110 can be calculated by inputting to the neural network, and the above table can be updated in real time as the action value function. In this case, for example, the weather condition of the area distributed by the power transmission / distribution line 110 may be added to the state of inputting to the neural network. Such weather conditions can be acquired from the server connected to the Internet 200 shown in FIG.

  As described above, according to the fourth embodiment, information related to voltage adjustment of the transmission / distribution line 110 is acquired for a predetermined time from the voltage adjustment device 3 in which the set value is set, and the feature amount is based on the acquired information. Or update the association between variance or standard deviation and settling value. Therefore, the relationship can be learned by repeating this.

  In addition, according to the fourth embodiment, the information acquired from the voltage adjustment device 3 adjusts the voltage by the voltage adjustment device 3 switching the tap and the degree that the voltage of the transmission and distribution line 110 deviates from the preset dead band region. And the number of times Therefore, the adjustment result of the voltage of the transmission and distribution line 110 can be quantitatively evaluated.

  Further, according to the fourth embodiment, the evaluation value of the adjustment result is updated in order to update the relationship between the feature value or the variance or the standard deviation and the settling value based on the evaluation value for evaluating the voltage adjustment result by the voltage adjusting device 3. The association can be updated so that becomes larger. That is, it is possible to automatically determine a settling value that can appropriately control the voltage of the transmission and distribution line under the conditions in the installed power system.

(Embodiment 5)
While the fourth embodiment is a form in which the relationship between the feature value or variance or standard deviation and the settling value is learned, the fifth embodiment has various states and weather conditions related to the transmission / distribution line 110, and transmission / distribution. In this embodiment, the relationship between the physical quantity and the feature quantity of the electric wire 110 is learned. Since the block configuration of the voltage regulator according to the fifth embodiment is the same as that of the voltage regulator 10 according to the first embodiment, portions corresponding to those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. In the following, standard deviation may be used instead of variance.

  As in the first or second embodiment, according to the set value determined by the feature value or the variance based on the physical quantity acquired before the current time, an appropriate voltage adjustment can be performed with respect to the voltage fluctuation that actually occurs in the transmission and distribution line 110. There are cases where it is not possible. For this reason, it is conceivable to predict a future situation such as “expected voltage fluctuation is expected in the future” and determine a set value based on a feature amount based on the prediction result.

  Various prediction methods are assumed, but if the data to be predicted is time-series data with continuity, prediction by time-series analysis is considered effective. As a specific prediction method, autoregression is assumed. On the other hand, if the target data is not stationary, for example, if there is a trend (change tendency) in the time series data, the difference (difference) in the data is taken, and if the change in the time series data is large, By taking the rate of change and logarithm, there is a possibility that continuity can be secured as time-series data, so it is considered effective to perform analysis after such processing.

  When the target data is not stationary, it is conceivable to perform prediction by machine learning in addition to processing the data. In the fifth embodiment, an example will be described in which a feature quantity of a physical quantity related to the transmission / distribution line 110 is predicted by reinforcement learning included in machine learning, and a set value is determined based on the predicted feature quantity. Machine learning by the settling value determination device 1 is not limited to reinforcement learning.

  Reinforcement learning here includes information relating to voltage adjustment of the transmission / distribution line 110, information indicating weather conditions, physical quantities relating to the transmission / distribution lines 110 (or feature quantities or variances calculated based on the physical quantities), and characteristics of the physical quantities. The relationship with quantity is learned as an action value table. Below, the flow of the process in the settling value determination apparatus 1 is demonstrated using figures.

  FIG. 14 is a block diagram illustrating an example of a functional configuration of the settling value determination device 1 according to the fifth embodiment. The settling value determination apparatus 1 includes an acquisition unit 201, a third acquisition unit 202, a fourth acquisition unit 203, a third calculation unit 204, a learning unit 205, a second determination unit 206, and a determination unit 207. . These functional blocks are realized by software processing executed by the control unit 2.

  The acquisition unit 201 acquires the voltage and current (physical quantity) of the transmission / distribution line 110 by the voltage detection unit 31 and the current detection unit 41, and observes the state of the transmission / distribution line 110. The third acquisition unit 202 acquires information related to voltage adjustment of the transmission and distribution line 110 from the voltage adjustment device 3 and observes the voltage adjustment state. The information relating to voltage adjustment includes the deviation amount Vout (p) from the dead zone region and the tap switching frequency Ntap (see the fourth embodiment). The third acquisition unit 202 is realized by the processing shown in steps S41 and S42 of FIG.

  The fourth acquisition unit 203 uses the communication unit 28 from a server connected to the Internet 200 to acquire information indicating weather conditions and observe weather conditions. The information indicating the weather condition includes, for example, the weather, temperature, humidity, and amount of solar radiation in the area where power is distributed by the transmission / distribution line 110. Along with the weather conditions or separately from the information indicating the weather conditions, time information such as date, day of the week, hour and minute may be acquired from a server connected to the Internet 200.

  The third calculation unit 204 calculates an evaluation value (reward) that evaluates the voltage adjustment result of the transmission and distribution line 110 based on the voltage adjustment state observed by the third acquisition unit 202. The third calculation unit 204 is realized by the processing shown in steps S43 to S46 in FIG.

  The learning unit 205 includes a state observed by the acquisition unit 201, the third acquisition unit 202, and the fourth acquisition unit (the state of the transmission and distribution line 110, the voltage adjustment state, and the weather state), and a third calculation unit. Based on the evaluation value (reward) calculated in 204, the behavior value corresponding to the current state and possible actions in the behavior value table is updated and learned. Instead of the state of the transmission / distribution line 110 observed by the acquisition unit 201, the learning unit 205 uses the feature quantity or variance calculated from the physical quantity related to the transmission / distribution line 110 acquired by the acquisition unit 201 as the state of the transmission / distribution line 110. May be referred to.

  The second determination unit 206 determines an optimal feature amount based on the current state and the action value learned by the learning unit 205. The determination unit 207 determines a set value based on the feature amount determined by the second determination unit 206. For example, as in the first embodiment, the first set value or the second set value is determined based on the comparison result between the feature amount and the predetermined threshold value, and the determined set value is set in the voltage regulator 3.

  In place of the learning unit 205 and the third calculation unit 204 shown in FIG. 14, each state (the state of the transmission / distribution line 110, the state of voltage adjustment, and the weather state) is input to the neural network for calculation, and the action value You can also update the table in real time. Further, in addition to the above state, time information acquired from a server connected to the Internet 200 may be added to a state where the time information is input to the learning unit 205 or the neural network. As a result, it is possible to predict a feature quantity that changes depending on the date, day of the week, hour, minute, or the like.

  As described above, according to the fifth embodiment, the information for the third time related to the voltage adjustment of the transmission and distribution line 110, the information indicating the weather condition, and the physical quantity (or the characteristic quantity calculated from the physical quantity) related to the transmission and distribution line 110 Alternatively, the relationship is learned by updating the relationship between the variance or the standard deviation) and the feature quantity of the physical quantity and repeating this. And based on the learned relationship, the feature-value showing the characteristic of the physical quantity which concerns on the transmission / distribution electric wire 110 is determined, and a settling value is determined based on the determined feature-value. Therefore, the feature quantity of the physical quantity related to the transmission / distribution line 110 can be predicted based on the learning result.

  In addition, according to the fifth embodiment, the behavior value table is updated based on the evaluation value for evaluating the voltage adjustment result by the voltage adjusting device 3, so that the evaluation value of the adjustment result is updated. be able to. That is, it is possible to automatically determine a settling value that can appropriately control the voltage of the transmission and distribution line under the conditions in the installed power system.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the meanings described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims. In addition, the technical features described in each embodiment can be combined with each other.

DESCRIPTION OF SYMBOLS 1 Setting value determination apparatus 2 Control part 201 Acquisition part 202 3rd acquisition part 203 4th acquisition part 204 3rd calculation part 205 Learning part 206 2nd determination part 207 Determination part 21 CPU
22 ROM
23 RAM
24 Timer 25, 27 Input unit 26 Output unit 28 Communication unit 3 Voltage adjustment device 30, 50 Measuring transformer 31, 51 Voltage detection unit 40 Current transformer 41 Current detection unit 10 Voltage adjustment device 100 Electric power system 110 Power distribution line 120 Transformer 121 Tap changer S_1, S_2 ... S_n Section L_1, L_2 ... L_n Load 200 Internet

Claims (18)

A settling value determining device for determining a settling value to be set in a voltage adjusting device for adjusting a voltage of a power transmission / distribution line of an electric power system,
An acquisition unit for acquiring a physical quantity related to the transmission and distribution line in time series;
An analysis unit for analyzing a frequency component of a physical quantity for a predetermined time acquired by the acquisition unit;
A settling value determining device comprising: a determining unit that determines the settling value based on the frequency component analyzed by the analyzing unit.   The set value determination apparatus according to claim 1, wherein the analysis unit analyzes a frequency component every time shorter than the predetermined time. A calculation unit that calculates a predetermined feature amount based on the frequency component analyzed by the analysis unit;
The settling value determining apparatus according to claim 1, wherein the determining unit determines a settling value based on the feature amount calculated by the calculating unit.   The settling value determination apparatus according to claim 3, wherein the feature amount is a ratio of a frequency component in a predetermined band to a frequency component analyzed by the analysis unit. A settling value determining device for determining a settling value to be set in a voltage adjusting device for adjusting a voltage of a power transmission / distribution line of an electric power system,
An acquisition unit for acquiring a physical quantity related to the transmission and distribution line in time series;
A calculation unit for calculating a variance or standard deviation of a physical quantity for a predetermined time acquired by the acquisition unit;
A settling value determining device comprising: a determining unit that determines the settling value based on the variance or standard deviation calculated by the calculating unit.   The settling value determination apparatus according to claim 5, wherein the calculation unit calculates a variance or a standard deviation every time shorter than the predetermined time.   7. The settling value determination according to claim 3, wherein the determination unit determines a settling value based on a comparison result between the feature amount or variance or standard deviation calculated by the calculation unit and a predetermined threshold value. apparatus. A second acquisition unit for acquiring information for a second time relating to the adjustment of the voltage from the voltage adjustment device;
The settling value determination device according to claim 7, further comprising: a second calculation unit that calculates the threshold based on information acquired by the second acquisition unit.   The set value determination apparatus according to claim 8, wherein the information includes information indicating a degree that the voltage of the transmission and distribution line deviates from a preset dead band region and a number of times that the voltage adjusting device has adjusted the voltage. A third acquisition unit for acquiring information for a third time relating to the adjustment of the voltage from the voltage adjustment device;
And a learning unit that updates a relationship between the feature amount or variance or standard deviation calculated by the calculation unit and a set value to be determined by the determination unit based on the information acquired by the third acquisition unit. Item 7. The settling value determination device according to any one of Items 3 to 6. A third acquisition unit for acquiring information for a third time relating to the adjustment of the voltage from the voltage adjustment device;
A fourth acquisition unit that acquires information indicating weather conditions;
Based on the information acquired by each of the third acquisition unit and the fourth acquisition unit, and the physical quantity acquired by the acquisition unit or the feature amount or variance or standard deviation calculated by the calculation unit, an action value table is created. A learning part to be updated,
A second determination unit that determines a feature quantity of the physical quantity based on the behavior value table updated by the learning unit;
The determination unit determines a set value based on the feature amount determined by the second determination unit instead of the feature amount or variance or standard deviation calculated by the calculation unit. The settling value determination device according to the item.   The information for the third time includes information indicating a degree that the voltage of the transmission and distribution line deviates from a preset dead band region and a number of times that the voltage adjusting device has adjusted the voltage. The settling value determination device described. A third calculation unit that calculates an evaluation value for evaluating the voltage adjustment result based on the information acquired by the third acquisition unit;
The set value determination apparatus according to any one of claims 10 to 12, wherein the learning unit updates the relationship or action value table based on the evaluation value calculated by the third calculation unit.   The settling value determination device according to claim 1, wherein the physical quantity is an effective value of a voltage on a power supply side or a load side with respect to the voltage adjustment device.   The settling value determination device according to any one of claims 1 to 13, wherein the physical quantity is an effective value of a current passing through the transmission / distribution line on a power supply side or a load side with respect to the voltage adjusting device.   A voltage regulator comprising: the settling value determination device according to any one of claims 1 to 15; and a voltage regulation device that adjusts the voltage of the power transmission and distribution line based on a set value set by the settling value determination device. . A settling value determining method for determining a settling value to be set in a voltage adjusting device for adjusting a voltage of a power transmission / distribution line of a power system,
Obtaining physical quantities related to the transmission and distribution lines in time series;
Analyzing the acquired frequency component of the physical quantity for a predetermined time;
A settling value determining method comprising: determining the settling value based on the analyzed frequency component. A settling value determining method for determining a settling value to be set in a voltage adjusting device for adjusting a voltage of a power transmission / distribution line of a power system,
Obtaining physical quantities related to the transmission and distribution lines in time series;
Calculating the dispersion or standard deviation of the acquired physical quantity for a predetermined time; and
Determining the settling value based on the calculated variance or standard deviation.

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