Optimal setting device and program for voltage regulators

Abstract

To provide an optimum setting device and optimum setting program for a voltage adjustment apparatus that make it possible to calculate setting values in a short time by eliminating power flow calculation every time an objective function is operated and so that the respective setting values do not deviate from settable ranges.SOLUTION: A setting device for performing operation processing to set reference voltage on the secondary side and line impedance within a voltage management range to optimum values, for a voltage adjustment apparatus such as an SVR, includes a computer system that uses an objective function taking, as decision variables, the reference voltage and the line impedance as setting items and performing approximation calculation by considering that a voltage change amount equal to a voltage adjustment amount by the voltage adjustment apparatus occurs in the voltage management range and executes a program obtained by formulating a constrained combination optimization problem taking upper and lower limit values of the setting items as a constraint condition to evaluate the objective function using predetermined input data for calculating a setting item combination maximizing its evaluated value as the optimum setting values.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to a technique for setting optimal values ​​of reference voltage and impedance set in the control device of voltage regulating devices such as load tap changing transformers (LRT) and automatic voltage regulators (SVR) installed in a power system. [Background technology]

[0002] As is well known, in voltage regulation equipment such as LRT and SVR, the control device that controls the tap switching on the secondary side is equipped with a current transformer (CT), a potential transformer (PT), a voltage regulation relay, and a line drop compensator (LDC). Here, the LDC is set with a resistance R and a reactance X according to the line impedance in the voltage control range, and compensates for the voltage drop that occurs based on the current and voltage detected by the CT and PT. In addition, a reference voltage V preset in the voltage regulation relay is ref Based on this voltage drop, the voltage in the voltage control range is determined as the reference voltage V ref In the following description, the LDC and the voltage regulating relay are collectively referred to as the voltage regulating device. For this reason, when generating a tap change command, the resistance R and reactance X set in the LDC and the reference voltage V set in the voltage adjustment relay are ref are extremely important values, and it is necessary to set these setting items (setting items of voltage regulating devices) to optimal values.

[0003] Conventionally, as this type of optimum setting technology, the inventions described in Patent Documents 1 and 2, for example, are known. That is, in the invention of Patent Document 1, the passing active current (passing active power) and passing reactive current (passing reactive power) of the SVR are set as explanatory variables, and the secondary ideal voltage of the SVR is set as the objective variable, and multiple regression analysis is performed to calculate the optimal setting values ​​of the reference voltage, resistance, and reactance. In addition, in the invention of Patent Document 2, each setting item of the voltage regulating device is treated as a discrete state variable, formulated as a combinatorial optimization problem, and the optimal setting value is calculated using Reactive Tabu Search (RTS), a type of metaheuristic as an approximate solution method. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5192425 (

[0035] to

[0043] , Figs. 1 to 4, etc.) [Patent Document 2] Patent No. 3809861 (

[0029] to

[0038] , Figure 2, etc.) Summary of the Invention [Problem to be solved by the invention]

[0005] Fig. 3 shows an example of a power system (power distribution system) equipped with voltage regulators. In the following description, the abbreviations of the devices will be used as reference symbols in the drawings. Normally, the range in which each setting item in a voltage regulator can be set is determined. For example, in a power system equipped with a substation LRT, a feeder circuit breaker FCB, an SVR, and a thyristor-type automatic voltage regulator TVR, as shown in Figure 3, taking the setting item (setting value) of the SVR as an example, the setting range is ref The voltage range is 95[V] to 119.5[V], the resistance R is 0[%] to 24[%], and the reactance X is 0[%] to 24[%]. Reference numeral 100 denotes a utility pole, 200 denotes a consumer, and the individual nodes from the FCB to the consumer 200 at the end are designated as nodes 1 to 10. The voltage management range of the LRT is nodes 1 and 2, the voltage management range of the SVR is nodes 5 to 8, and the voltage management range of the TVR is nodes 11 and 12. Fig. 3 will be described in detail in the embodiment described later.

[0006] However, when the optimal setting value is obtained by multiple regression analysis as in Patent Document 1, the calculated setting value may deviate from the above-mentioned possible setting range. For example, FIG. 4 shows the SVR's active and reactive currents (FIG. 4(a)), and secondary ideal voltage (FIG. 4(b)) used to calculate the set values ​​according to Patent Document 1, and FIGS. 5(a) and 5(b) show the calculation results of each set value. Here, "in LDC mode" in FIG. 5(a) refers to the reference voltage V ref , resistance R LDC , reactance X LDC The normal operation mode in which the V ref ,R LDC ,X LDC This is the operation mode in which the above is set. According to Fig. 5(a) and (b), in both the LDC mode and the ProCon LDC combined mode, LDC The value is -1[%], which is outside the aforementioned adjustable range (0[%] to 24[%]).

[0007] Moreover, the optimal setting method described in Patent Document 2 includes a step of searching, by RTS, for optimal setting value candidates that satisfy an objective function (Equation 1 below) that determines the minimum value of the deviation of the system voltage from a specified value, the active power loss, and the sum of the voltage and current constraint deviations under predetermined constraint conditions.

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[0008] In Equation 1, l is the number of load states to be considered (the number of maximum load states, minimum load states, etc.), m is the number of nodes, and V i : voltage at node i, V r : Voltage regulation value, n: Number of branches, Loss j : active power loss of branch j, g(V,I): absolute sum of voltage and current constraint deviations, w k : Weighting coefficients for each term in the objective function.

[0009] However, in this conventional technique, a power flow calculation is performed to calculate the voltage of each node each time the objective function is calculated, which poses a problem of requiring a long calculation time.

[0010] Therefore, the problem to be solved by the present invention is to provide an optimal setting device and an optimal setting program for a voltage regulator which solves the problem of each setting item going outside its setting range and which makes it possible to calculate setting values ​​in a short period of time. [Means for solving the problem]

[0011] In order to solve the above problem, the optimal setting device for a voltage regulator according to claim 1 is as follows: An optimum setting device for a voltage regulator installed in a power system, which uses arithmetic processing by a computer system to set a reference voltage on the secondary side of the voltage regulator and resistance and reactance corresponding to a line impedance within a voltage management range of the voltage regulator to optimum values, The computer system includes: The method is characterized in that a program is executed which formulates a constrained combinatorial optimization problem in which the reference voltage, the resistance, and the reactance as setting items are set as decision variables, an objective function is used which performs an approximate calculation by assuming that an amount of voltage change equal to the amount of voltage regulation by the voltage regulating device occurs in the voltage control range, and upper and lower limit values ​​of the setting items are set as constraints, and the objective function is evaluated using input data related to the power system and the voltage regulating device, and the combination of the setting items which gives the highest evaluation value is calculated as an optimal setting value.

[0012] The optimal setting device for a voltage regulator according to claim 2 is the voltage regulator according to claim 1, The computer system is characterized by executing either or both of an exact solution program that evaluates the objective function for all combinations of possible values ​​of the reference voltage, the resistance, and the reactance, or an approximate solution program using metaheuristics.

[0013] The optimal setting device for a voltage regulator according to claim 3 is the voltage regulator according to claim 2, The computer system is characterized in that, using the approximate solution program, it repeatedly executes a series of processes in which the objective function is evaluated and the optimal setting values ​​are updated each time a solution search point is updated, until a maximum number of iterations is reached, and then it repeatedly executes the initialization process of the search points and the series of processes until a maximum number of trials is reached.

[0014] The voltage regulator optimum setting device according to claim 4 is any one of claims 1 to 3, The objective function is a function that minimizes the square of the difference between an ideal secondary voltage obtained by adding the secondary voltage of the voltage regulator obtained by power flow calculation and the voltage regulation amount by the voltage regulator, and the ideal secondary voltage of the voltage regulator taking into account the line voltage drop in the voltage management range.

[0015] The optimal setting device for a voltage regulator according to claim 5 comprises any one of claims 1 to 4, The input data includes at least node data and branch data of the power system, arbitrarily set upper and lower voltage limit data, as well as the rated value of the voltage regulating device, the upper and lower limit values ​​of each setting item, and the interval width within the upper and lower limit values.

[0016] The voltage regulator optimal setting program according to claim 6 comprises: An optimal setting program for a voltage regulator installed in a power system, which optimizes a reference voltage on the secondary side of the voltage regulator and a resistance and reactance corresponding to a line impedance within a voltage management range of the voltage regulator through calculations performed by a computer system, comprising: a first step of acquiring input data relating to the power system and the voltage regulator; a second step of formulating a constrained combinatorial optimization problem using an objective function that performs an approximation calculation by assuming that the reference voltage, the resistance, and the reactance as setting items are set as decision variables and that a voltage change amount equal to the voltage adjustment amount by the voltage adjustment device occurs in the voltage control range, and that sets upper and lower limit values ​​of the setting items as constraint conditions; a third step of calculating, as an optimal setting, a combination of the setting items that maximizes the evaluation value of the objective function; The present invention is characterized in that the computer system is caused to execute at least the above.

[0017] The voltage regulator optimal setting program according to claim 7 is the voltage regulator optimal setting program according to claim 6, The input data includes at least node data and branch data of the power system, arbitrarily set upper and lower voltage limit data, as well as the rated value of the voltage regulating device, the upper and lower limit values ​​of each setting item, and the interval width within the upper and lower limit values.

[0018] The voltage regulator optimal setting program according to claim 8 is the program according to claim 6 or 7, a step of calculating a secondary ideal voltage by power flow calculation, the secondary ideal voltage being the sum of the secondary ideal voltage of the voltage regulator and an amount of voltage regulation by the voltage regulator, between the first step and the second step; The second step is characterized in that the constrained combinatorial optimization problem is formulated using the objective function that minimizes the square of the difference between the secondary side ideal voltage and the secondary side ideal voltage of the voltage regulating device taking into account the line voltage drop in the voltage management range.

[0019] The optimal setting program for a voltage regulating device according to claim 9 is characterized in that the optimal setting program described in any one of claims 6 to 8 is either or both of an exact solution program that evaluates the objective function for all combinations of values ​​that the reference voltage, the resistance, and the reactance can take, or an approximate solution program using metaheuristics.

[0020] The optimal setting program for a voltage regulating device according to claim 10 is characterized in that, by using the approximate solution program described in claim 9, a series of processes for evaluating the objective function and updating the optimal setting value each time a solution search point is updated is repeatedly executed until a maximum number of iterations is reached, and then an initialization process of the search point and the series of processes are repeatedly executed until a maximum number of trials is reached. Effect of the Invention

[0021] According to the present invention, the setting values ​​of the voltage regulating devices do not deviate from the settable range, and the complicated power flow calculations required each time an objective function is calculated are eliminated, making it possible to calculate the specified setting values ​​in a short time. [Brief description of the drawings]

[0022] [Figure 1] 4 is a flowchart showing a processing procedure of an optimal setting program according to the embodiment of the present invention. [Diagram 2] 2 is a flowchart in the case where Particle Swarm Optimization (PSO) is used in the setting value calculation step in FIG. 1 . [Diagram 3] 1 is a configuration diagram of a power system to which an embodiment of the present invention is applied; [Figure 4] 1 is a graph showing an active current passing, a reactive current passing, and a secondary ideal voltage of an SVR used in calculating a setting value according to Patent Document 1. [Diagram 5] FIG. 2 is an explanatory diagram of each setting value according to Patent Document 1. [Figure 6] FIG. 4 is an explanatory diagram of node data and branch data in the power system of FIG. [Figure 7] FIG. 4 is an explanatory diagram of input data according to the embodiment of the present invention. [Figure 8] FIG. 4 is an explanatory diagram of optimal setting data according to the embodiment of the present invention. [Figure 9] FIG. 4 is an explanatory diagram of a secondary side ideal voltage in the embodiment of the present invention. [Figure 10]3 is a conceptual diagram showing how search point position data and initial search points are generated when the method of FIG. 2 is used. FIG. [Figure 11] 3 is a conceptual diagram showing how search point update data and search point position information are updated when the method of FIG. 2 is used. FIG. [Figure 12] FIG. 3 is an explanatory diagram of each setting value and an evaluation result when the method of FIG. 2 is used. [Figure 13] FIG. 1 is a diagram showing the overall configuration of a computer system for realizing an optimal setting device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a flow chart showing the processing procedure of the optimal setting program according to this embodiment, which is executed by a processor such as a CPU constituting a computer system.

[0024] In Fig. 1, in step S10 where input data is read, the node data and branch data in the power system in Fig. 3 described above are stored in a database. Fig. 6(a) is an example of the node data, and Fig. 6(b) is an example of the branch data. Here, the SVR and TVR are linked to the node data and branch data by node numbers 3 and 4, and node numbers 9 and 10, respectively.

[0025] In addition, in step S10, various data that are predefined for the LRT, SVR, and TVR in FIG. 3 are stored in the database as voltage regulation device data as shown in FIG. 7(a), and the lower and upper voltage limits that the user has arbitrarily set are stored in the database as upper and lower voltage limit data as shown in FIG. 7(b). Furthermore, when using a metaheuristic method such as Particle Swarm Optimization (PSO) to calculate the setting values, the optimization method data shown in FIG. 7(c) required for the calculation is stored in the database.

[0026] Next, in step S20 in FIG. 1, the power flow calculation is performed with the SVR and TVR in FIG. 3 fixed to the through tap (not in operation). This power flow calculation determines the minimum voltage V min (Voltage value of node 8) and maximum voltage V max (voltage value of node 6), secondary voltage V SVR , the effective power P SVR and reactive power Q SVR are calculated for each of the 24 hours of a day, and these values ​​are stored in the database of optimal setting data shown in FIG. 8 (the secondary side ideal voltage in FIG. 8 is calculated in the next step S30). The above minimum voltage V min and maximum voltage V max is converted to the secondary voltage of the pole transformer and stored.

[0027] In step S30 of FIG. 1, the lower limit voltage value and the upper limit voltage value of FIG. 7(b), the minimum voltage, the maximum voltage, and the secondary side voltage at time n on day t in the voltage management range shown in FIG. 8 (= the V SVR ) is used to calculate the ideal secondary voltage at time t on day n, and the calculated voltage is stored in the database of optimal setting data shown in FIG. 8. The calculation formula for the secondary side ideal voltage is as shown in Equation 2.

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[0028] In formula 2, V s (n,t): secondary ideal voltage at time t on day n, V(n,t): secondary voltage at time t on day n, ΔV(n,t): voltage adjustment amount at time t on day n, V U : Upper voltage limit, V L : Lower limit voltage, V max (n,t): Maximum voltage at time t on day n of the voltage control range, V min (n, t): The minimum voltage at time t on day n in the voltage control range.

[0029] Here, the amount of voltage fluctuation that occurs at a node within the voltage management range due to the operation of a voltage regulator can be calculated by an approximation that fluctuates by the amount of voltage regulation by the voltage regulator. For example, if the amount of voltage regulation by the SVR is α, the voltage of the node within the voltage management range of the SVR also fluctuates by α. Furthermore, assuming that a voltage regulator such as an SVR can continuously adjust the voltage, as shown in Figure 9, the voltage upper limit value V U and the maximum voltage V of the voltage control range max The absolute value of the difference with (n,t), that is, |V U -V max (n,t)|(=ΔV U ) and the lower voltage limit V L and the voltage control range minimum voltage V min The absolute value of the difference with (n,t), that is, |V L -V min (n,t)|(=ΔV L ) is equal to the voltage regulation amount ΔV(n,t), and this voltage regulation amount ΔV(n,t) is added to the secondary side voltage V(n,t) as shown in Equation 2 and FIG. 9 to obtain the secondary side ideal voltage V s (n,t) can be found. In this embodiment, the above-mentioned secondary ideal voltage V s The purpose is to calculate each setting value so that the difference between (n, t) and the ideal secondary voltage described below, which takes into account the line voltage drop in the voltage control range, is minimized.

[0030] Next, step S40 in FIG. 1 is a step for formulating and calculating the optimal setting values ​​for each setting item as a combinatorial optimization problem with constraints, which constitutes the main part of the present invention. Here, the optimal setting values ​​for SVR, TVR, and LRT are calculated by evaluating an objective function using an approximation function with the upper and lower limits of each setting item as the decision variables and the SVR, TVR, and LRT settings in Figure 3 as constraints. Below, (A) decision variables, (B) objective functions, and (C) constraint conditions are explained for each mode.

[0031] (A) Decision variables (a) LDC mode V ref : Reference voltage for setting, R LDC :Settling resistance, X LDC :Settling reactance (b) Procon LDC combined mode V ref (t) (1≦t≦24): Setting reference voltage, R LDC :Settling resistance, X LDC :Settling reactance V ref In LDC mode, V is a fixed value throughout the day, and in the ProCon LDC combined mode, V is a different value every hour. Note that all decision variables are discrete values. For example, in the SVR in Figure 3, V ref (t) is 0.5[V] increment, R LDC and X LDC The increment is 1%.

[0032] (B) About the objective function (a) LDC mode The following formula 3 is for the SVR, the reference voltage V ref and the voltage drop of the line in the voltage control range as the secondary ideal voltage of the SVR. Similarly, Equation 4 is a formula for calculating the secondary ideal voltage for the TVR, and Equation 5 is a formula for calculating the secondary ideal voltage for the LRT.

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[0033] In these formulas 3 to 5, V' SVRs (n,t): Ideal secondary voltage considering the line voltage drop of the SVR at time t on date n, V SVRn : Rated voltage of SVR, P SVRn : Rated capacity of SVR, P SVR (n,t): SVR passing active power at time t on date n, Q SVR(n,t): reactive power passing through the SVR at time t on date n, V SVR (n,t): Secondary voltage of SVR at time t on date n, PT SVR : PT ratio (transformer ratio) of SVR, V' TVRs (n,t): Ideal secondary voltage considering the line voltage drop of the TVR at time t on date n, P TVR (n,t): TVR passing active power at time t on date n, Q TVR (n,t): reactive power passing through the TVR at time t on date n, V TVR (n,t): TVR secondary voltage at time t on date n, V' LRTs (n,t): Ideal secondary voltage considering the line voltage drop of the LRT at time t on day n, P LRT (n,t): LRT passing active power at time t on day n, Q LRT (n,t): LRT reactive power passing on day n at time t, V LRT (n,t): LRT secondary voltage at time t on day n, CT LRT : CT ratio (current transformation ratio) of LRT, PT LRT :PT ratio (transformer ratio) of LRT.

[0034] Objective function f for SVR, TVR, and LRT SVR ,f TVR ,f LRT is the secondary ideal voltage V s (n, t) and the secondary ideal voltage V' taking into account the line voltage drop in Equation 3 to Equation 5 SVRs (n,t),V' TVRs (n,t),V' ’ LRTs The objective function f is defined so that the sum of the squares of the differences between (n,t) and SVR ,f TVR ,f LRT This is expressed as Equation 6 to Equation 8.

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[0035] As described above, in this embodiment, the voltage fluctuation occurring at the node within the voltage management range due to the voltage adjustment of the voltage regulator is calculated by an approximation calculation that changes by the amount of voltage adjustment, and the objective function using the result is evaluated to determine the settling reference voltage V refL , setting resistance R LDC , and settling reactance X LDC The combination of these is calculated, and no load flow calculation is required to evaluate the objective function.

[0036] (b) Procon LDC combined mode In this mode, V in the above-mentioned formulas 3 to 5 and formulas 6 to 8 ref V ref By replacing (t) with (t), the secondary ideal voltage V ’ SVRs (n,t),V ’ TVRs (n,t),V ’ LRTs (n, t) is expressed by formulas 9 to 11, and the objective function is expressed by formulas 12 to 14. The definitions of the values ​​in Formulas 9 to 14 are the same as those explained in Formulas 3 to 8.

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[0037] (C) Constraints Setting reference voltage V ref , setting resistance R LDC, and settling reactance X LDC The constraint conditions for are set as shown in Equation 15 based on the upper and lower limit constraints of each setting item in the voltage regulator data of FIG.

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[0038] As described above, according to this embodiment, when finding optimal setting values ​​as a constrained combinatorial optimization problem, constraint conditions determined from upper and lower limit constraints for each setting item are set. This solves the problem of calculating setting values ​​that exceed the settable range as in Patent Document 1, and makes it possible to calculate appropriate setting values. In addition, by determining the amount of voltage fluctuation occurring at nodes within the voltage management range through approximate calculation, power flow calculations are not required when evaluating the objective function, and the setting values ​​can be calculated in a shorter time than with the conventional technology in which power flow calculations are performed each time an objective function is evaluated, as in Patent Document 2.

[0039] In this way, the settling reference voltage V refL , setting resistance R LDC , and settling reactance X LDC Once the optimum values ​​are calculated, the results of these calculations are recorded, displayed, or transmitted to the outside via steps S50 and S60 in FIG.

[0040] The above constrained combinatorial optimization problem may be solved by an exact solution method or an approximate solution method. For example, when finding the optimal setting value of TVR in Fig. 3, if the constrained combinatorial optimization problem of LDC mode is solved by the exact solution method, the number of combinations is V ref There are seven values ​​of R LDC There are 51 possible values ​​for the settling reactance X LDC Since there are 51 possible values ​​for , the total number of combinations, 18207 (= 7 × 51 × 51), is evaluated using the objective function of Equation 7, and the combination of setting values ​​with the highest evaluation (smallest evaluation value) is output as the optimal setting value.

[0041] In addition, when finding the optimal setting value of SVR in Figure 3, if you want to solve the constrained combinatorial optimization problem of the Procon LDC combined mode (the total number of combinations is 51 x 25 x 25 x 24 = 765,000) using an approximate solution method, you can use, for example, Particle Swarm Optimization (PSO), which is a type of metaheuristic. FIG. 2 is a flowchart showing a case where the process corresponding to step S40 in FIG. 1 is executed by PSO.

[0042] First, in step S41 in Fig. 2, the search points are initialized using random numbers under the constraints of the above-mentioned formula 15. As a result, the initial search points having the search point position information shown in Fig. 10(a) are generated as shown in Fig. 10(b). In step S42, the position data of each initial search point is evaluated using the objective function of equation 12. In step S43, the smallest evaluation value obtained in step S42 is set as the best solution. Furthermore, in step S44, search point update data as shown in FIG. 11(a) is calculated based on the update formula of the PSO, and the search point position information is updated based on this calculation result as shown in FIG. 11(b). At this time, the decision variables are rounded using the step size of each device in the voltage regulator data in Fig. 7(a). By rounding the decision variables in this way, PSO, which targets continuous optimization problems, can also be applied to optimal setting of voltage regulators defined as a constrained combinatorial optimization problem as in this embodiment.

[0043] The procedure of steps S42 to S44 is executed until the current number of search points reaches the maximum number of search points (step S45), and further, the procedure of steps S42 to S45 is executed until the number of iterations reaches the maximum number of iterations (step S46). In addition, since the metaheuristic generates the initial search points by random numbers, the results may vary. Taking this into consideration, the above steps S41 to S46 are repeated until the maximum number of trials is reached, and the combination with the highest evaluation value among the obtained combinations of decision variables is output as the best solution (step S47).

[0044] Next, Figures 12(a) and (b) show the results of calculating each setting value by the PSO of this embodiment using the same input data as when each setting value in Figure 5 was obtained by Patent Document 1. From Figures 12(a) and (b), it can be seen that all setting items are within the settable range. FIG. 12(c) shows the result of the settling in Patent Document 1, assuming that R LDC 12(c) shows the result of comparing the evaluation value of the objective function when = 0 with the evaluation value of the objective function by the PSO of this embodiment. According to this Fig. 12(c), the superiority of this embodiment over the conventional technology of Patent Document 1 is clear in both the LDC mode and the process control / LDC combined mode.

[0045] Next, FIG. 13 is a diagram showing the overall configuration of a computer system such as a personal computer or a workstation that realizes the optimal setting device. In Fig. 13, a CPU 11 executes an optimum setting program and controls the operation of the entire system in accordance with each step of Fig. 1 and Fig. 2. A memory 12 stores the optimum setting program as well as a communication control program for communicating with a higher-level control device. The input unit 13 is a keyboard, mouse, touch panel, etc. for inputting operational commands including system start / stop commands and various input operations, and the output unit 14 is a display, printer, speaker, etc. for displaying, printing, outputting the calculated optimal setting values, etc. by voice, etc.

[0046] The storage unit 15 is, for example, a hard disk drive (HDD) or a solid state drive (SSD), and stores the databases shown in Figures 6 and 7. These databases may be stored in a removable recording medium 17 such as a CD-ROM, DVD, or USB memory, and may be loaded via the recording medium drive unit 16, or may be stored as a structure in the memory 12. Alternatively, the database may be downloaded from a host control device such as a system control server to the network connection unit 18 via the Internet or an intranet and then incorporated into the system. The optimal setting values ​​calculated by the CPU 11 executing the optimal setting program may be transmitted to the host control device via the network connection unit 18, and a system may be constructed in which the host control device automatically sets these optimal setting values ​​in the voltage regulators. [Explanation of symbols]

[0047] 11: CPU 12: Memory 13: Input section 14: Output section 15: Storage part 16: Recording medium drive unit 17: Recording media 18: Network connection section 100: Electric pole 200: Consumer

Claims

1. An optimum setting device for a voltage regulator installed in a power system, which uses arithmetic processing by a computer system to set a reference voltage on the secondary side of the voltage regulator and resistance and reactance corresponding to a line impedance within a voltage management range of the voltage regulator to optimum values, The computer system includes: an optimal setting device for a voltage regulator, comprising: a program that executes a program in which the reference voltage, the resistance, and the reactance as setting items are decision variables, an objective function is used that performs an approximate calculation by assuming that an amount of voltage change equal to the amount of voltage regulation by the voltage regulator occurs in the voltage control range, and upper and lower limit values ​​of the setting items are used as constraints, and the program evaluates the objective function using input data related to the power system and the voltage regulator, thereby calculating, as an optimal setting value, the combination of the setting items that results in the highest evaluation value.

2. In the optimal setting device for a voltage regulator according to claim 1, The computer system includes: An optimal setting device for a voltage regulator, characterized in that it executes either or both of a program for an exact solution method that evaluates the objective function for all combinations of values ​​that the reference voltage, the resistance, and the reactance can take, and a program for an approximate solution method using metaheuristics.

3. In the optimum setting device for a voltage regulator according to claim 2, The computer system includes: The optimal setting device for a voltage regulator is characterized in that, according to the program for the approximate solution, a series of processes for evaluating the objective function and updating the optimal setting value each time a search point of a solution is updated is repeatedly executed until a maximum number of iterations is reached, and then an initialization process of the search point and the series of processes are repeatedly executed until a maximum number of trials is reached.

4. In the optimal setting device for a voltage regulator according to any one of claims 1 to 3, Optimal setting device for a voltage regulator, wherein the objective function is a function that minimizes the square of the difference between an ideal secondary voltage obtained by adding the secondary voltage of the voltage regulator obtained by power flow calculation and the voltage regulation amount by the voltage regulator, and the ideal secondary voltage of the voltage regulator taking into account line voltage drop in the voltage control range.

5. In the optimal setting device for a voltage regulator according to any one of claims 1 to 4, An optimal setting device for a voltage regulator, wherein the input data includes at least node data and branch data of the power system, and arbitrarily set upper and lower voltage limit data, as well as the rated value of the voltage regulator, the upper and lower limit values ​​of each setting item, and the interval width within the upper and lower limit values.

6. An optimal setting program for a voltage regulator installed in a power system, which optimizes a reference voltage on the secondary side of the voltage regulator and a resistance and reactance corresponding to a line impedance within a voltage management range of the voltage regulator through calculations performed by a computer system, comprising: a first step of acquiring input data relating to the power system and the voltage regulator; a second step of formulating a constrained combinatorial optimization problem using an objective function that performs an approximation calculation by assuming that the reference voltage, the resistance, and the reactance as setting items are set as decision variables and that a voltage change amount equal to the voltage adjustment amount by the voltage adjustment device occurs within the voltage management range, and that sets upper and lower limit values ​​of the setting items as constraint conditions; a third step of calculating, as an optimal setting, a combination of the setting items that maximizes the evaluation value of the objective function; The voltage regulator optimal setting program is characterized by causing the computer system to execute at least the above.

7. 7. The voltage regulator optimal setting program according to claim 6, Optimal setting program for a voltage regulator, wherein the input data includes at least node data and branch data of the power system, and arbitrarily set upper and lower voltage limit data, as well as a rated value of the voltage regulator, upper and lower limit values ​​of each setting item, and an increment width within the upper and lower limit values.

8. In the voltage regulator optimal setting program according to claim 6 or 7, a step of calculating a secondary ideal voltage by power flow calculation, the secondary ideal voltage being the sum of the secondary ideal voltage of the voltage regulator and an amount of voltage regulation by the voltage regulator, between the first step and the second step; the second step formulates the constrained combinatorial optimization problem using the objective function that minimizes the square of the difference between the secondary side ideal voltage and the secondary side ideal voltage of the voltage regulator taking into account a line voltage drop in the voltage control range.

9. The voltage regulator optimum setting program according to any one of claims 6 to 8, An optimal setting program for a voltage regulating device, characterized in being either or both of an exact solution program that evaluates the objective function for all combinations of possible values ​​of the reference voltage, the resistance, and the reactance, and an approximate solution program using metaheuristics.

10. 10. An optimal setting program for a voltage regulator, comprising: a program for the approximate solution method according to claim 9, which executes a series of processes for evaluating the objective function and updating the optimal setting value each time a search point of a solution is updated until a maximum number of iterations is reached, and then executes an initialization process of the search point and the series of processes repeatedly until a maximum number of trials is reached.

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