JP3594785B2 - Power system voltage controller - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power system voltage control device, and is particularly suitable when applied to a case where a target voltage is maintained by operating a power transformer system and a phase adjustment system.
[0002]
[Prior art]
In the conventional power system voltage control, a local control method in which a power system voltage control device is independently installed for each facility is mainly used. For example, as a local control method, a method of determining a tap operation amount of a specific transformer facility according to a deviation amount from a target value when a specific voltage value and a reactive power value exceed a dead zone (Hayashi et al. "Voltage reactive power control method", IEEJ, Vol.
[0003]
Further, as a conventional voltage control of a power system, there is a schedule control for operating a power system phase adjustment facility based on a schedule in which operation times are set.
In addition, there is a centralized control system that manages the states of all the transformer facilities and all the phase adjustment facilities in a target power system in one place. For example, as a centralized control method, a method of determining an objective function representing economy and control effect and determining a facility state for optimizing the objective function in a certain time section (Sasaki et al., “Voltage / Reactive Power Control Support System” Development ", 1995 IEEJ National Convention, No. 1344).
[0004]
[Problems to be solved by the invention]
However, in the conventional local control system, since each facility operates individually, there is a problem that operation interference between facilities occurs, causing voltage fluctuations and excessive operation of facilities. On the other hand, if the dead zone of the voltage monitoring is set to be large in order to suppress the excessive operation of the equipment, there is a problem that the control is delayed.
[0005]
Further, in the conventional schedule control, equipment operation is performed at a set time and number of times, so that there is a problem that it is not possible to cope with a sudden change in the state of the power system.
Furthermore, in the conventional centralized control method, in the method of optimizing the objective function, the optimization of the system state in a certain time section is guaranteed, but when the control is continuously performed in real time, the control effect is not improved. There has been a problem that the operation is biased or vibrated for a specific equipment having a high cost, and it is difficult to harmonize the equipment state within a continuous time.
[0006]
Therefore, an object of the present invention is to provide a power system voltage control device capable of performing real-time harmonization of equipment states within a continuous time.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems, according to the present invention, based on system information of a power system, an evaluation index creating unit that creates an evaluation index value for evaluating a system state of the power system, Request index creating means for creating a request index value representing the current operation request degree from the equipment operation plan, and using the evaluation index value and the request index value to determine the operation necessity of the phase adjustment equipment and the transformer equipment. I am trying to do it.
[0008]
This makes it possible to change the specific gravity of the degree of operation required for the transformer equipment and the phase adjustment equipment in accordance with the time transition of the required index value, and it is possible to harmonize the equipment state in continuous time in real time. .
[0009]
Further, according to one aspect of the present invention, both the request index value (reflecting the operation plan of the operator) and the evaluation index value (reflecting the current system state) are input in parallel by fuzzy inference. Is determined.
[0010]
Thereby, while the equipment operation is performed in accordance with the required index value, if there is a sudden change in the system status of the power system, it is possible to perform the operation according to the sudden change.
Further, according to one aspect of the present invention, in a time zone where the required index value of the phase adjustment equipment is large, the degree of operation necessity of the phase adjustment equipment is increased, and the degree of operation necessity of the transformer equipment is reduced. .
[0011]
This makes it possible to adjust the ratio of the operation frequency of the phase adjustment equipment and the transformer equipment according to the time zone, thereby preventing the interference and excessive operation of the operation of the phase adjustment equipment and the transformer equipment.
Further, according to one aspect of the present invention, a request index value is created in consideration of a daily load transition.
[0012]
This makes it possible to harmonize the equipment operation not only in a certain time section but also in a continuous time (for example, within a day).
Further, according to one aspect of the present invention, when there are a plurality of candidates for the operation target equipment selected by the operation target equipment selection means, the equipment having high necessity of operation is specified, and the unnecessary operation target equipment is removed. I have to.
[0013]
As a result, if only transformer equipment is selected, it is checked whether there is any phase adjustment equipment whose operation necessity was at a certain value or more at that time. The phase adjustment equipment can be operated, and the operation time of the phase adjustment equipment, which should be operated in the near future, can be advanced. As a result, excessive operation can be prevented.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a power system voltage control device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a power system voltage control apparatus according to one embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an electric power system voltage control device, 2 denotes an evaluation index creation unit that creates an evaluation index value 4 of a system state using control information and system information 17 of an electric power system 16, and 3 denotes equipment operation based on the control information. Request index creation means for creating a request index value 5 representing the degree of demand, 4 is an evaluation index value of the system state of the electric power system 16, 5 is a required index value of equipment operation, and 6 is the operation necessity of the transformer equipment and the phase adjustment equipment. Means for determining the degree of operation required of the transformer, 7 is a processing unit for determining the degree of operation required for the transformer equipment, 8 is a processing unit for determining the degree of operation required for the phase adjustment equipment, 9 is the degree of operation required for each equipment, and 10 is the operation target. Operation target equipment selection means for selecting a candidate for equipment, 11 indicates data representing the selected candidate for the equipment and the operation method, and 12 indicates an operation target equipment for specifying the equipment to be actually operated from the candidate for the operation target equipment. Means, 13 is an operation pair Data representing equipment and operation methods, 14 is a control information storage unit for storing control information, 15 is a control information editing function for editing control information, 16 is a power system to be controlled, 17 is system information of a power system 16 It is. The control information includes, for example, a control rule for determining the operation of the transformer and the phase adjustment equipment, a membership function for determining the degree of conformity of the evaluation index value and the required index value, and a determination of the degree of operation required for the transformer and the phase adjustment equipment. There are a membership function, an evaluation threshold, a weighting factor, and an operation suppression time.
[0015]
Hereinafter, the operation of the power system voltage control device 1 will be described.
In FIG. 1, an evaluation index creating unit 2 removes noise included in the system information 17 and creates an evaluation index value 4 for evaluating the system state of the power system 16. Moving average processing or the like is used as a method for removing noise. For example, the following values are obtained as evaluation index values.
[0016]
i) Deviation between each substation voltage and target voltage
ii) Voltage difference between each substation voltage
iii) A value obtained by calculating a weighted average value for the difference between each substation voltage and the target voltage
iv) Amount of change in active power per unit time
When creating these evaluation index values, control information stored in the control information storage unit 14 is used. Note that the control information used here includes, for example, the number of data points for performing a moving average calculation and a weight coefficient for performing a weighted average calculation. After creating the evaluation index value 4, the evaluation index creating unit 2 outputs it to the operation necessity degree determining unit 6.
[0017]
The request index creating means 3 determines, with respect to the operation schedule table of the equipment determined by the equipment operator, which time zone the current time belongs to, and determines the degree to which the time zone belongs as a request index value. calculate. After creating the requirement index value 5, the requirement index creating means 3 outputs it to the operation necessity degree determining means 6.
[0018]
The operation necessity degree judging means 6 includes a judgment processing part 7 for judging the operation necessity degree of the transformer equipment and a judgment processing part 8 for judging the operation necessity degree of the phase adjustment equipment. The determination processing units 7 and 8 perform fuzzy inference processing using the evaluation index value 4 and the request index value 5 as input data and the control information stored in the control information storage unit 14, thereby transforming the transformer facilities and the phase adjustment. Judge the necessity of operation of the equipment. When performing fuzzy inference processing, control information includes control rules for determining the operation of transformers and phase adjustment equipment, membership functions for determining the suitability of evaluation index values and required index values, and operation of transformers and phase adjustment equipment. A membership function or the like for determining the degree of necessity is used. For example, when operating a transformation ratio tap as a transformation facility, a control rule for the degree of operation necessity is set to perform the following tap operation.
[0019]
i) The tap is lowered when the system voltage is high, and the tap is raised when the system voltage is low. Further, when the active power is decreasing, the tap-down operation is advanced, and when the active power is increasing, the tap-up operation is advanced.
[0020]
ii) If the required index value of the SC (phase-adjusting capacitor) operation increases, the tap operation is suppressed.
FIG. 2 is a diagram illustrating an example of a control rule for tap operation determination according to an embodiment of the present invention.
[0021]
In FIG. 1 to NO. In the fifteen control rules, the determination result of the tap operation necessity degree when the voltage deviation and the active power change are used as the evaluation index value 4 is shown. In addition, NO. 16 and NO. The control rule of No. 17 shows the determination result of the tap operation necessity degree when the voltage deviation is used as the evaluation index value 4 and the SC required index value is used as the required index value 5.
[0022]
For example, when the absolute value of the required index value of the SC is small, the operation necessity degree determining means 6 sets the NO. 16 or NO. Since the degree of establishment of the seventeen control rules is small, the final output (the necessary degree of tap operation) is not significantly affected. However, as the absolute value of the required index value of the SC increases, the NO. 16 or NO. The degree of satisfaction of the seventeenth control rule is increased, and the final output is suppressed. Here, if the required index value of the SC is made to continuously increase as an input, the final output can be gradually suppressed accordingly.
The control rule based on the SC required index value makes it possible to suppress the value of the tap operation necessity value. From the viewpoint of system operation, the tap operation necessity degree becomes higher as the request for performing the SC operation increases. It is possible to prevent interference between the two.
[0023]
FIG. 3 is a diagram illustrating an example of a control rule for determining operation of the phase adjustment capacitor according to the embodiment of the present invention. In FIG. 18 to NO. In the control rule of 32, the judgment result of the SC operation necessity degree when the voltage deviation and the active power change are used as the evaluation index value 4 and the SC required index value is used as the required index value 5 is shown. .
[0024]
FIG. 4A is a diagram illustrating an example of a membership function of the voltage deviation according to the embodiment of the present invention. In FIG. 4A, the membership function of the voltage excursion includes fuzzy labels such as “negative direction”, “positive direction”, “large in negative direction”, and “negative direction”. "Slightly large", "near the target value", "slightly large in the positive direction", and "large in the positive direction" are set, and the degree of conformity to the voltage deviation is defined for each fuzzy label.
[0025]
FIG. 4B is a diagram illustrating an example of a membership function of a change in active power according to an embodiment of the present invention.
In FIG. 4B, “decrease direction”, “almost constant”, and “increase direction” are set as fuzzy labels in the membership function of the active power change, and each fuzzy label is adapted to the active power change. Degree is defined.
[0026]
FIG. 4C is a diagram illustrating an example of a membership function of a required index value of the phase adjustment capacitor according to the embodiment of the present invention.
In FIG. 4C, “opening request”, “maintenance status”, and “input request” are set as fuzzy labels in the membership function of the required index value of the phase adjustment capacitor. The degree of conformity to the required index value of the phase adjustment capacitor is defined.
[0027]
FIG. 5A is a diagram illustrating an example of a membership function of a tap operation necessity degree according to an embodiment of the present invention.
In FIG. 5 (a), the membership function of the tap operation necessity degree includes, as consequent labels, “large in the down direction”, “medium in the down direction”, “small in the down direction”, and “maintain the current state”. , "Small in the up direction", "medium in the up direction", and "large in the up direction", and the relevance to the tap operation necessity is defined for each consequent part label.
[0028]
FIG. 5B is a diagram showing an example of a membership function of the degree of operation necessity of the phase adjustment capacitor according to the embodiment of the present invention.
In FIG. 5B, the membership functions of the operation necessity degree of the phase adjustment capacitor include consequent labels “large in the opening direction”, “medium in the opening direction”, “small in the opening direction”, "Maintain the status quo", "Small in the throwing direction", "Medium in the throwing direction", and "Large in the throwing direction" are set. For each consequent label, the degree of conformity to the operation necessity of the phase adjustment capacitor is defined. Have been.
[0029]
The operation target equipment selection unit 10 in FIG. 1 selects a candidate for an operation target equipment by comparing the threshold value stored in the control information storage unit 14 and the degree of necessity of operation of each equipment. . For example, assuming that the threshold value for the closing operation of the capacitor for phase adjustment is a1, a2 (> 0) and the threshold value for the opening operation is b1, b2 (<0), the capacitor for phase adjustment is It is determined whether or not the operation target candidate.
[0030]
i) When [degree of necessity of operation of phase adjustment capacitor]> a1
→ The capacitor for phase adjustment is set as a candidate for the capacitor for phase adjustment to be applied.
[0031]
ii) [degree of necessity of operation of capacitor for phase modulation] <a1,
And when [degree of necessity of operation of the capacitor for phase adjustment]> a2
→ The capacitor for phase adjustment will be a candidate for a capacitor for phase adjustment that will be turned on in the near future.
[0032]
iii) When [the degree of operation necessity of the phase adjustment capacitor] <b1
→ The phase adjustment capacitor is a candidate for the phase adjustment capacitor to be opened.
[0033]
iv) When [degree of necessity of operation of capacitor for phase adjustment]> b1 and [degree of necessity of operation of capacitor for phase adjustment] <b2
→ The capacitor for phase adjustment will be a candidate for a capacitor for phase adjustment to be opened in the near future.
[0034]
v) Other than the above
→ Exclude the phase adjustment capacitor from the candidates for operation.
The operation target equipment specifying means 12 specifies the target equipment to be actually operated and the operation method from the candidates for the operation target equipment selected by the operation target equipment selection means 10 according to the following procedure.
[0035]
i) Identification of equipment considering operation intervals
Equipment whose elapsed time from the previous operation performed in the target power system 16 to the current time is smaller than the minimum operation interval defined in the control information storage unit 14 is excluded from the operation targets. At this time, the minimum operation interval is set to a unique value for each facility.
[0036]
ii) Identification of equipment considering the number of operations
Equipment in which the number of operations counted from a certain time to the present exceeds the maximum number of operations defined in the control information storage unit 14 is excluded from the operation targets.
[0037]
iii) Identification of equipment to prevent over-operation
If only the transformer equipment is selected as the operation target, check if there is no candidate for the equipment to be operated in the near future among the phase adjustment equipment. , Excluding transformer equipment from operation.
[0038]
Hereinafter, a method of calculating the degree of necessity of operating the phase adjustment capacitor and the tap when the required index value of the phase adjustment capacitor changes according to the time zone will be described more specifically.
[0039]
FIG. 6 is a diagram showing an example of a schedule pattern of required index values of the phase adjusting capacitor according to the embodiment of the present invention.
In FIG. 6, the required index value of the phase adjustment capacitor is defined for each time, and the required index value of the phase adjustment capacitor is small before and after noon.
[0040]
Hereinafter, the description will be made on the assumption that the evaluation index value 4 and the request index value 5 given as inputs are the following values.
i) “Voltage deviation” = 0.5 [kV]
ii) “Change in active power” = 0.8 [MW / min]
iii) “Required index value of phase-adjusting capacitor” = 1.0 (10:00 am)
Given these conditions, by using the membership functions shown in FIGS. 4A to 4C, “voltage deviation”, “active power change”, and “required index value of phase adjustment capacitor” Evaluate the status of
[0041]
FIG. 7A is a diagram illustrating a method of calculating the fitness when the voltage deviation is 0.5 kV using the membership function of FIG. 4A.
In FIG. 7A, the state of “voltage deviation” = 0.5 [kV] corresponds to the fuzzy label “slightly large in the positive direction”, the fuzzy label “large in the positive direction”, and the fuzzy label “positive direction”. Belongs to ". Here, the degree (fitness) belonging to the fuzzy label “slightly large in the positive direction” = 1.0, the degree (fitness) belonging to the fuzzy label “large in the positive direction” = 0.3, the fuzzy label “positive” (Degree of conformity) = 0.8.
[0042]
FIG. 7B is a diagram showing a method of calculating the fitness when the active power change is 0.8 MW / min using the membership function of FIG. 4B.
In FIG. 7B, the state of “active power change” = 0.8 [MW / min] belongs to the fuzzy label “almost constant” and the fuzzy label “increase direction”. Here, the degree (fitness) belonging to the fuzzy label “almost constant” = 0.2 and the degree (fitness) belonging to the fuzzy label “increase direction” = 0.5.
[0043]
FIG. 7C is a diagram illustrating a method of calculating the fitness when the required index value of the phase adjustment capacitor is 1, using the membership function of FIG. 4C.
In FIG. 7 (c), the state in which “required index value of the capacitor for phase adjustment” = 1.0 belongs to the fuzzy label “maintain current” and the fuzzy label “input request”. Here, the degree (fitness) belonging to the fuzzy label “maintenance” = 0.0 and the degree (fitness) belonging to the fuzzy label “input request” = 0.9.
[0044]
When the degree of conformity of each state of “voltage deviation”, “active power change”, and “required index value of the capacitor for phase adjustment” is determined, the control relating to the necessity of the tap operation is performed by referring to FIGS. 2 and 3. A rule and a control rule relating to the necessity of the SC operation are obtained. As a result, as a control rule regarding the degree of necessity of the tap operation, NO. 2, NO. 3, NO. 5 and NO. 6 holds.
[0045]
When a control rule to be satisfied is determined, the degree of conformity of the entire rule is determined. As a method of obtaining the fitness of the entire rule, there is a method of using the smaller fitness of the fuzzy labels as the fitness of the entire rule. There is also a method of taking the product of the fitness of each fuzzy label to obtain the fitness of the entire rule. In the following description, the smaller one of the fitness levels of the fuzzy labels is used as the fitness level of the entire rule.
[0046]
The control rule NO. For 2, the fitness of the fuzzy label “large in the positive direction” = 0.3 and the fitness of the fuzzy label “almost constant” = 0.2, the smaller fitness is taken, and the entire rule is taken. Is 0.2.
[0047]
The control rule NO. With regard to No. 3, since the fitness of the fuzzy label “larger in the positive direction” is 0.3 and the fitness of the fuzzy label “increase” is 0.5, the smaller fitness is taken and the entire rule is taken. Is 0.3.
[0048]
The control rule NO. In the case of No. 5, since the fitness of the fuzzy label "slightly larger in the positive direction" is 1.0 and the fitness of the fuzzy label "almost constant" is 0.2, the smaller fitness is taken. The overall fitness = 0.2.
[0049]
The control rule NO. In the case of No. 6, since the fitness of the fuzzy label “larger in the positive direction” is 1.0 and the fitness of the fuzzy label “increase” is 0.5, the smaller fitness is taken, and Is 0.5.
[0050]
When the conformity of the entire rule is determined for the established control rule, the conclusion of each rule is determined by applying the conformance of the entire rule to the consequent part label. As a result, the conclusion of each rule is NO. As for the consequent part, the label of the consequent part is “medium in the down direction” × 0.2, and the control rule NO. With regard to No. 3, the consequent part label is “smaller in the downward direction” × 0.3, and the control rule NO. With respect to No. 5, the consequent part label is “medium in the down direction” × 0.2, and the control rule NO. With regard to No. 6, the consequent part label is “maintain current” × 0.5.
[0051]
On the other hand, there is no control rule regarding the degree of necessity of the SC operation.
When the conclusion of each rule is obtained, in the membership function of FIG. 5, a figure obtained by multiplying the figure corresponding to the consequent label of the established control rule by the fitness of the entire rule is synthesized. Then, the final fuzzy inference value is obtained by obtaining the center of gravity of the synthesized figure.
[0052]
FIG. 8 is a diagram illustrating a method of calculating the tap operation necessity when the required index value of the phase adjustment capacitor is 1, using the membership function of FIG.
In FIG. 8, regarding the necessity of tap operation, as a conclusion of the rule, the consequent label “medium in the down direction” × 0.2, the consequent label “small in the down direction” × 0.3, the consequent The department label “maintain current” × 0.5 has been determined. As a result, by multiplying a triangle corresponding to “medium in the down direction” by 0.2, a triangle A1 having a vertex fitness of 0.2 of the triangle is generated. Further, by multiplying a triangle corresponding to “small in the downward direction” by 0.3, a triangle B1 having a vertex fitness of 0.3 of the triangle is generated. By multiplying by 0.5, a triangle C1 is generated in which the degree of fitness of the vertices of the triangle is 0.5.
[0053]
When the triangles A1, B1, and C1 are generated, the barycentric position of the figure obtained by combining the triangles A1, B1, and C1 is determined to be -0.18, and the barycentric position is set as the tap operation necessity.
[0054]
If a plurality of rules having the same conclusion in the consequent part label are simultaneously established, the conclusion with the higher fitness is adopted (OR operation is performed).
On the other hand, the fuzzy inference value is “none” because the control rule of the phase adjustment capacitor has not been satisfied at all. However, when there is no fuzzy inference value in the system design, the operation requirement degree is assumed to be “0”. I do.
[0055]
Next, in FIG. 6, the degree of necessity of operating the phase adjustment capacitor and the tap when the time changes from 10 am to 11:50 am is determined. Here, it is assumed that “voltage deviation” and “active power change” have not changed between 10:00 am and 11:50 am. When the time changes from 10:00 a.m. to 11:50 a.m., as shown in FIG. 6, the "required index value of the phase adjustment capacitor" changes from 1.0 to -0.7. As a result, the evaluation index value 4 and the request index value 5 given as inputs are the following values.
i) “Voltage deviation” = 0.5 [kV]
ii) “Change in active power” = 0.8 [MW / min]
iii) “Required index value of phase adjusting capacitor” = − 0.7 (11:50 am)
FIG. 9 is a diagram illustrating a method of calculating the degree of conformity when the required index value of the phase adjustment capacitor is −0.7 by using the membership function of FIG. 4C.
[0056]
In FIG. 9, the state in which “the required index value of the phase adjustment capacitor” = − 0.7 belongs to the fuzzy label “maintain the current state” and the fuzzy label “open request”. Here, the degree (fitness) belonging to the fuzzy label “maintenance” = 0.2 and the degree (fitness) belonging to the fuzzy label “open request” = 0.7.
[0057]
Note that the calculation of the degree of conformity in each state of “voltage deviation” and “active power change” is the same as in the case of FIGS. 7A and 7B. In other words, the state of “voltage deviation” = 0.5 [kV] corresponds to the degree (fitness) belonging to the fuzzy label “slightly large in the positive direction” = 1.0 and the fuzzy label “large in the positive direction”. The degree of belonging (fitness) = 0.3, and the degree of belonging (fitness) to the fuzzy label “positive direction” = 0.8. The state of “active power change” = 0.8 [MW / min] is a degree (fitness) belonging to the fuzzy label “substantially constant” = 0.2 and a degree (fitness) belonging to the fuzzy label “increase direction”. ) = 0.5.
[0058]
When the degree of conformity of each state of “voltage deviation”, “active power change”, and “required index value of the capacitor for phase adjustment” is determined, the control relating to the necessity of the tap operation is performed by referring to FIGS. 2 and 3. A rule and a control rule relating to the necessity of the SC operation are obtained. As a result, as a control rule regarding the degree of necessity of the tap operation, NO. 2, NO. 3, NO. 5, NO. 6 and NO. 17 is established. Further, as a control rule regarding the degree of necessity of the tap operation, NO. 19, NO. 20, NO. 22 and NO. 23 is established. When a control rule to be satisfied is determined, the degree of conformity of the entire rule is determined.
[0059]
The control rule NO. For 2, the fitness of the fuzzy label “large in the positive direction” = 0.3 and the fitness of the fuzzy label “almost constant” = 0.2, the smaller fitness is taken, and the entire rule is taken. Is 0.2.
[0060]
The control rule NO. With regard to No. 3, since the fitness of the fuzzy label “larger in the positive direction” is 0.3 and the fitness of the fuzzy label “increase” is 0.5, the smaller fitness is taken and the entire rule is taken. Is 0.3.
[0061]
The control rule NO. In the case of No. 5, since the fitness of the fuzzy label "slightly larger in the positive direction" is 1.0 and the fitness of the fuzzy label "almost constant" is 0.2, the smaller fitness is taken. The overall fitness = 0.2.
[0062]
The control rule NO. In the case of No. 6, since the fitness of the fuzzy label “larger in the positive direction” is 1.0 and the fitness of the fuzzy label “increase” is 0.5, the smaller fitness is taken and the entire rule is taken. Is 0.5.
[0063]
The control rule NO. For 17, since the fitness of the fuzzy label “positive direction” = 0.8 and the fitness of the fuzzy label “open request” = 0.7, the smaller fitness is taken. The fitness of the entire rule = 0.7.
[0064]
The control rule NO. For 19, the fitness of the fuzzy label "large in the positive direction" = 0.3, the fitness of the fuzzy label "almost constant" = 0.2, and the fitness of the fuzzy label "open request" = 0.7 Therefore, the smallest fitness is taken, and the fitness of the entire rule is 0.2.
[0065]
The control rule NO. For 20, the fitness of the fuzzy label “large in the positive direction” = 0.3, the fitness of the fuzzy label “increase direction” = 0.5, and the fitness of the fuzzy label “open request” = 0.7. Therefore, the smallest fitness is taken, and the fitness of the entire rule is 0.3.
[0066]
The control rule NO. With regard to the fuzzy label “slightly larger in the positive direction”, the fitness of the fuzzy label “substantially constant” = 0.2, and the fitness of the fuzzy label “open request” = 0. 7, the smallest fitness is taken, and the fitness of the entire rule is 0.2.
[0067]
The control rule NO. 23, the fitness of the fuzzy label "slightly larger in the positive direction" = 1.0, the fitness of the fuzzy label "increase direction" = 0.5, and the fitness of the fuzzy label "open request" = 0. 7, the smallest matching degree is taken, and the matching degree of the entire rule is 0.5.
[0068]
When the conformity of the entire rule is determined for the established control rule, the conclusion of each rule is determined by applying the conformance of the entire rule to the consequent part label. As a result, the control rule NO. As for the consequent part, the label of the consequent part is “medium in the down direction” × 0.2, and the control rule NO. With regard to No. 3, the consequent part label is “smaller in the downward direction” × 0.3, and the control rule NO. With respect to No. 5, the consequent part label is “medium in the down direction” × 0.2, and the control rule NO. With regard to No. 6, the consequent part label is “Maintain Current Status” × 0.5, and the control rule NO. For 17, the consequent part label is “maintain current” × 0.7.
[0069]
In the control rule of FIG. Regarding 19, the consequent part label is “medium opening necessity” × 0.2, and the control rule NO. For 209, the consequent part label is "the degree of opening necessity is small" .times.0.3, and the control rule NO. Regarding No. 22, the consequent label “opening necessity is small” × 0.2, and the control rule NO. For 23, the consequent part label is “maintain current” × 0.5.
[0070]
When the conclusion of each rule is obtained, in the membership function of FIG. 5, a figure obtained by multiplying the figure corresponding to the consequent label of the established control rule by the fitness of the entire rule is synthesized. Then, the final fuzzy inference value is obtained by obtaining the center of gravity of the synthesized figure.
[0071]
FIG. 10A is a diagram illustrating a method of calculating the tap operation necessity when the required index value of the phase adjustment capacitor is −0.7 by using the membership function of FIG. 5A. is there.
[0072]
In FIG. 10A, as to the degree of necessity of tap operation, the conclusion of the rule is that the consequent label “medium in the down direction” × 0.2 and the consequent label “small in the down direction” × 0.3. The consequent label “maintain current” × 0.5 and the consequent label “maintain current” × 0.7 are determined. Here, for the consequent part label “maintain current”, two rules of the same conclusion are simultaneously established, but here, the conclusion with the higher degree of conformity is adopted. As a result, by multiplying the triangle corresponding to “medium in the downward direction” by 0.2, a triangle A2 having a vertex fitness of 0.2 of the triangle is generated. Further, by multiplying a triangle corresponding to “small in the downward direction” by 0.3, a triangle B2 having a vertex fitness of 0.3 of the triangle is generated. Further, by multiplying the triangle corresponding to “maintain the status quo” by 0.7, a triangle C2 having a vertex fitness of 0.7 of the triangle is generated.
[0073]
When the triangles A2, B2, and C2 are generated, the position of the center of gravity of the figure obtained by combining the triangles A2, B2, and C2 = -0.12 is determined, and the position of the center of gravity is used as the tap operation necessity.
[0074]
FIG. 10B shows a method for calculating the degree of operation necessity of the phase adjustment capacitor when the required index value of the phase adjustment capacitor is −0.7 by using the membership function of FIG. 5B. FIG.
[0075]
In FIG. 10 (b), regarding the degree of operation necessity of the phase adjustment capacitor, as a conclusion of the rule, the consequent part label “medium opening necessity” × 0.2, and the consequent part label “low opening necessity” × 0.3, consequent part label “small opening necessity” × 0.2, and consequent part label “maintain current” × 0.5. Here, with regard to the consequent part label “opening degree is small”, two rules of the same conclusion are simultaneously established, but here, the conclusion with the larger matching degree is adopted. As a result, by multiplying a triangle corresponding to “medium opening necessity” by 0.2, a triangle A3 having a vertex fitness of 0.2 of the triangle is generated. Further, by multiplying the triangle corresponding to “the degree of opening is small” by 0.3, a triangle B3 having a vertex of the triangle having a fitness of 0.3 is generated. Further, by multiplying the triangle corresponding to “maintain the current state” by 0.5, a triangle C3 having a vertex fitness of 0.5 of the triangle is generated.
[0076]
When the triangles A3, B3, and C3 are generated, the position of the center of gravity of the figure obtained by combining the triangles A3, B3, and C3 = -0.18 is obtained, and the position of the center of gravity is determined as the operation necessity of the phase adjustment capacitor.
[0077]
As described above, even if the “voltage deviation degree” and the “active power change” given as the evaluation index value 4 are exactly the same, if the “SC required index value” is changed over time, the control rule that is satisfied is established. Since the degree of adaptation and the degree of adaptation change, the degree of necessity of tap and SC operation can be changed.
[0078]
【The invention's effect】
As described above, according to the present invention, the required index value and the evaluation index value are used as common input data to calculate the degree of operation necessity between the transformer equipment and the phase adjustment equipment by fuzzy inference, whereby the time required for the required index value is calculated. It is possible to change the specific gravity of the degree of necessity of operation of the transformer and the phase adjusting equipment according to the transition. For this reason, it is possible to reflect the operation plan of the operator in equipment operation in addition to the current system status, and perform equipment operation according to the required index value. It can be performed.
[0079]
Further, according to one aspect of the present invention, in a time zone before and after noon when the required index value of the phase adjustment equipment is large, the degree of operation necessity of the phase adjustment equipment is increased, and the degree of operation necessity of the transformer equipment is reduced. Accordingly, the ratio of the operation frequency of both facilities can be adjusted according to the time zone, and interference between the operations of both facilities and excessive operation can be prevented.
[0080]
In addition, according to one aspect of the present invention, by creating a request index value that also takes into account the load transition of a day, not only a certain time section but also a continuous time (for example, within a day). Equipment operation can be harmonized.
[0081]
Further, according to one aspect of the present invention, when only the transformer equipment is selected as the operation target equipment, it is checked whether there is any phase adjustment equipment whose operation necessity degree is equal to or more than a certain value at that time, and this is satisfied. If there is, by operating the phase adjustment equipment in place of the transformer equipment, it becomes possible to advance the operation time of the phase adjustment equipment to be operated in the near future, and it is possible to prevent excessive operation .
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a power system voltage control device according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of a control rule for determining tap operation according to an embodiment of the present invention.
FIG. 3 is a diagram illustrating an example of a control rule for determining operation of a phase adjustment capacitor according to an embodiment of the present invention.
4A is a diagram illustrating an example of a membership function of a voltage deviation according to an embodiment of the present invention, and FIG. 4B is a diagram illustrating a membership function of a change in active power according to an embodiment of the present invention; FIG. 3C is a diagram illustrating an example of a membership function of a required index value of the phase adjustment capacitor according to an embodiment of the present invention.
FIG. 5A is a diagram illustrating an example of a membership function of the degree of necessity of tap operation according to an embodiment of the present invention, and FIG. 5B is a diagram illustrating a phase adjustment capacitor according to an embodiment of the present invention; It is a figure showing an example of the membership function of the operation necessity degree.
FIG. 6 is a diagram showing an example of a schedule pattern of required index values of the phase adjusting capacitor according to one embodiment of the present invention.
7A is a diagram illustrating a method of calculating the fitness when the voltage deviation is 0.5 kV using the membership function of FIG. 4A, and FIG. 7B is a diagram illustrating a change in active power; Is a diagram showing a method of calculating the fitness when the value is 0.8 MW / min by using the membership function of FIG. 4B, and FIG. 4C shows the case where the required index value of the phase adjustment capacitor is 1. FIG. 5 is a diagram illustrating a method of calculating a degree of fitness using the membership function of FIG.
FIG. 8 is a diagram showing a method for calculating the necessity of tap operation when the required index value of the phase adjustment capacitor is 1, using the membership function of FIG. 5A.
FIG. 9 is a diagram showing a method of calculating the degree of conformity when the required index value of the phase adjustment capacitor is −0.7 by using the membership function of FIG. 4C.
10A shows a method for calculating the degree of tap operation necessity when the required index value of the phase adjusting capacitor is −0.7 by using the membership function of FIG. 5A. FIG. 5B shows a method for calculating the degree of operation necessity of the phase adjustment capacitor when the required index value of the phase adjustment capacitor is -0.7 by using the membership function of FIG. FIG.
[Explanation of symbols]
1 Power system voltage controller
2 Evaluation index creation means
3 Requirement index creation means
4 System status evaluation index values
5 Required index values for equipment operation
6 Operation necessity judgment means
7 Judgment processing unit of operation necessary degree of transformer equipment
8 Judgment processing unit of operation necessity degree of phase adjustment equipment
9 Necessity of operation of each facility
10 Operation target equipment selection means
11 Selected equipment candidates and operation method
12 Operation target equipment identification means
13 Equipment to be operated and operation method
14 Control information storage
15 Control information editing function
16 Power system
17 System information

Claims (6)

Evaluation index creating means for creating an evaluation index value for evaluating a system state of the power system based on system information of the power system,
A request index creating means for creating a request index value indicating a current operation request degree from a facility operation plan created in advance,
By performing fuzzy inference using the evaluation index value and the request index value, operation necessity degree determination means for determining the necessity degree of operation of the phase adjustment equipment and the transformer equipment,
Based on the operation necessary degree, operation target equipment setting means for selecting a candidate for the phase adjustment equipment or transformer equipment to be operated,
Based on the operation state of the phase adjustment equipment or the transformer equipment, an operation target equipment specifying unit that identifies a phase adjustment equipment or a transformer equipment to be operated from among candidates of the phase adjustment equipment or the transformer equipment. Power system voltage controller. The operation necessity degree determination means includes:
Request index conformity calculating means for calculating the degree of conformity to which the current request index value belongs to a membership function defining the size of the request index value;
Evaluation index matching degree calculation means for calculating the degree of fitness to which the current evaluation index value belongs to a membership function that defines the magnitude of the evaluation index value,
The degree of operation necessity of the transformation equipment and the phase adjustment equipment is determined by using a combination of the fitness to which the evaluation index value belongs and the fitness to which the request index value belongs. Power system voltage controller. First storage means for storing a membership function defining a degree of conformity to the size of the request index value;
Second storage means for storing a membership function that defines a degree of conformity to the magnitude of the evaluation index value;
Third storage means for storing a membership function that defines a degree of adaptation to the degree of operation necessity of the phase adjustment facility;
Fourth storage means for storing a membership function that defines a degree of adaptation to the degree of operation required for the transformer equipment;
Fifth storage means for storing a state of the operation necessity degree of the phase adjustment facility in association with the state of the request index value and the state of the evaluation index value;
The storage device according to claim 1, further comprising: a sixth storage unit configured to store a state of the degree of operation necessity of the transformer equipment in association with the state of the request index value and the state of the evaluation index value. Power system voltage controller. The operation necessity degree determination means includes:
The power system voltage control device according to any one of claims 1 to 3, wherein the degree of operation necessity of the transformer equipment is adjusted based on the magnitude of the required index value of the phase adjustment facility. The request index creating means,
The request index value representing the magnitude of the current request for equipment operation is created by combining the operation request content in the equipment plan created in advance and the load transition pattern for one day. The power system voltage controller according to any one of claims 1 to 4. The operation target equipment specifying means,
When a transformer is selected as a candidate for the operation target equipment, a determination unit that determines whether there is a phase adjustment equipment that is operated within a predetermined period from the operation necessity degree,
6. A method according to claim 1, further comprising the step of: when there is a phase adjustment facility in which the operation is performed within a predetermined period, an alternative means for specifying the phase adjustment facility as an operation target facility in place of the selected transformer facility. The power system voltage control device according to any one of the above items.

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