JP3249275B2 - Transmission voltage adjustment processing device in distribution system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission voltage adjustment processing device in a power distribution system for improving the instability of a supply voltage due to a change in load and constantly supplying a constant voltage to consumers in a power system.

[0002]

2. Description of the Related Art Conventionally, a voltage transmitted from a substation is calculated once a year based on a load curve and distribution line current assumed for each season and data stored in a distribution system database.
Each time, the calculation was performed using a computer, and based on the result, the optimum transmission voltage of the bank was determined for each quarter, and the operation of controlling by a program was performed.

[0003]

According to the above-mentioned conventional method, the LR (load voltage regulator, the same applies hereinafter) tap is raised and lowered based on the bank voltage set by the program setting device installed in the substation. Was doing. However, in order to determine the optimum bank transmission voltage, it is necessary to perform calculations for each bank of the substation and set a program, which requires a great deal of time and effort. Further, when the load on the distribution line fluctuates, the bank sending voltage must be quickly adjusted, and it is difficult to cope with these fluctuations. The present invention has been made in view of the above circumstances, and provides a transmission voltage adjustment processing device in a distribution system capable of supplying a substantially constant voltage to a customer even when the load on a distribution line fluctuates. It is an object.

[0004]

An arrangement for achieving the above object will be described with reference to FIG. The transmission voltage adjustment processing device 10 according to the present invention includes a data input unit 11 that takes in a computer a voltage value or a current value obtained at a fixed period (for example, every 15 minutes) via each remote monitoring control device, and a power distribution system. System information storage means 12 for storing equipment and load information and information indicating how each equipment is configured, based on the variable load data from the data input means and information from the system information storage means At predetermined intervals (for example, every 30 minutes)
And an optimum value calculation means 13 for calculating an optimum transmission voltage value of the bank, and a bank control means 14 for controlling the bank transmission voltage based on the calculation result from the optimum value calculation means. Reference numeral 1 denotes a remote control device master station (referred to as a TM master station) on the substation side, and a remote control device slave station (referred to as a TM slave station) 1-1.
Input the distribution line breaker 1-2 and current information via the.
2 is the TC master station on each switch side, 2-1 and 2-2 are TC slave stations,
Reference numerals 3 and 31 denote switches.

[0005]

The load fluctuation data of the bank, each switch, and the distribution line notified via each remote control device (TC, TM master station) is input to the data input means. Each of these values notifies the optimum value calculation means of data. Using the distribution system database stored in the system information storage unit and the load variation data, the optimum value calculation unit calculates the voltage drop of each distribution system and calculates the optimal bank voltage. Then, the bank LR control device is controlled in real time by the bank control means so as to have the calculated bank voltage.

[0006]

FIG. 2 is a block diagram of an embodiment of a transmission voltage adjusting processing apparatus according to the present invention. In FIG. 2, reference numeral 21 denotes a load fluctuation data input device, which is a distribution line current which is load fluctuation data;
The bank voltage and distribution lines are divided into a plurality of sections, or the voltages and currents of the division switches interconnecting the distribution lines are collected at regular intervals (for example, every 15 minutes). Reference numeral 22 denotes a distribution system database in which information (switching information, numerical information, etc.) of various distribution systems is stored. 23 is an optimum bank sending voltage calculating means for calculating an optimum value at predetermined intervals (for example, every 30 minutes) based on various data stored in the power distribution system database. Reference numeral 24 denotes a bank LR control device, which controls the LR up / down based on the calculation result of the transmission voltage.

Next, the operation will be described. First, the distribution line current value, the bank voltage value,
The voltage and current values at the switch point are taken in. Based on the values from the load fluctuation data input device 21 and the data from the distribution system database 22, the optimal bank transmission voltage is determined by the optimal bank transmission voltage calculating means,
The bank LR control device 24 controls the state of the distribution line so as to always maintain a constant voltage.

FIG. 3 is a flowchart showing the flow of the entire process. If the process is a bank to be calculated / controlled in step S31 in the figure, an optimum bank sending voltage adjustment calculation is performed on the bank in step S32. In step S33, it is first determined whether or not the bank is for performing tap elevating control by the power distribution computer. This is because some banks only perform calculations and do not perform control. If this is a control target, if the difference between the bank voltage used for calculating the voltage adjustment value and the bank voltage at the time of controlling the on-load voltage regulator (hereinafter referred to as LR) is less than the one tap up / down value in step S34. , No change is determined. This is because there is no sudden change during the calculation. Even if there is a large change (voltage drop etc.) in the ordinary distribution line, there is no big change in the bank.

In such a case, it is abnormal. If there is no change, it is determined whether or not the LR is automatic in step S35, and if it is automatic, it is switched to manual in step S36. The manual here is only for the LR, and the LR
If LR is not set manually, the LR is
This is because tap control is performed from the beginning, and it becomes meaningless even if the distribution computer performs tap control. Then, the tap is moved up and down in step S37 to reflect the calculation result. On the other hand, if it is not a control target in step S33, it is determined in step S38 whether or not the bank is a bank in which the LR is returned to automatic (that is, controlled by the system control). Judge,
If it is manual, LR is automatically set in step S391. In some banks, the LR is manually set to keep the voltage constant during work or the like, and tap control is not performed. If it is determined in step S38 that the bank is not the LR automatic return bank, or if it is determined in step S39 that the LR is not manual, the process ends.

FIG. 4 is a flowchart showing the details of the optimum bank transmission voltage adjustment value calculation process (step S32 in FIG. 3). First, the variable load data of the power source / load side switch is obtained (step S41), and the allowable voltage value is calculated based on the data (step S42). If it exceeds the permissible voltage value (step S43), the number of customers deviating from the permissible value is calculated (step S44). If the number of deviating customers is decreasing (step S45), the process proceeds to step S42. The information is stored with the permissible voltage value as the best solution (step S46).
Then, the LR tap is moved up and down (step S47) (however, the actual up and down control is not yet performed at this time), the voltage at each switch point is raised and lowered (step S48), and the process returns to step S42. On the other hand, if the allowable voltage value does not exceed the allowable voltage value in step S43, the information is stored as the allowable voltage value in step S42 as the optimal solution (step S49), and the information is stored in step S43 in FIG.
Move the processing to 33. If the number of deviating consumers has not decreased in step S45, the process directly proceeds to step S33 in FIG.

Next, a description will be given of voltage value / current value data required for calculating the optimum value in steps S41 and S42. FIG. 5 illustrates a method of calculating a switch passing current. For all the switches on the power supply path, the passing current is calculated by the following formula (1) in order from the power transmission switch to the terminal section to the power supply side switch.

## EQU1 ## WS (i) = WCF (n) + WS (1) WS (i): Current passing through switch (i) WCF (n): Switch (i) performs power transmission Section (n)
Load current ΣWS: Total switch passing current flowing out from section (n) (however, it is 0A in the terminal section)

In FIG. 5, the passing current 65A of the switch SW1 is the sum of the load current 20A of the section C2 where power is transmitted by the switch SW1 and the switch passing current flowing out of the section C2 (15A + 10A).
A + 20A). Further, an average passing current WCT (k, 1) between the current inflow switch (k) and the current outflow switch (1) in the section is calculated by the following equation (2).

(Equation 2) The calculated average passing current value is multiplied by the impedance between the current inflow switch (k) and the current outflow switch (1), and a voltage value between the switches is calculated by a voltage value described below. Used.

FIG. 6 illustrates a method of calculating a voltage value. Switches that can measure voltage values (SW1, SW
The voltage value of (3, SW4) uses the measured value as it is, and for the other switches (SW2, SW5) for which the voltage value cannot be measured, the voltage value is previously obtained from the measured value of the measurable switch on the power supply side. It is obtained by subtracting the sum of the voltage drop values for each section route at each switch point. At this time, the voltage value V _SW2 of the switch _SW2 is expressed by the following equation (3).

(Equation 3) VR (1,2) means a voltage drop between switches 1 and 2, and VR (2,3) means a voltage drop between switches 2 and 3.

Next, the acquisition of the voltage values of the power-supply-side and load-side switches will be described. When acquiring the voltage values of the power-side and load-side switches from the voltage values of all the switches connected to the switch section, if there are multiple load-side switches, the minimum Take the voltage value. When there is no load-side switch, the voltage value of the load-side switch is the same as the voltage value of the power-side switch. When the voltage value of the load-side / power-side switch exceeds the range of 6000 to 7000 V,
Processing is stopped as voltage mismatch.

Next, the calculation of the allowable voltage value in step S42 will be described. The permissible voltage value (upper / lower limit value) immediately below the transformer and at the end of the low voltage line is calculated for each switch section. If the voltage at the switch installation point is higher than the bank sending voltage due to the distribution line, or if the voltage characteristics are completely different from other distribution lines, the section is considered as a specific section. The calculation formulas (4), (5), (6), and (7) for the allowable voltage value are shown below.

[0016]

(In the case of immediately below the transformer) Upper limit value = {(101 + m) + (TD + TRD) * n} * Tap value for each section / 105 ............ (4) Lower limit value = ｛(101-m) + (TD + TRD) * n｝ * Tap value for each section / 105 ............ (5) (at low voltage line end) Upper limit = {(101 + m) + (TD + LWD) * n} * Tap for each section Value / 105 …… (6) Lower limit value = {(101−m) + (TD + LWD) * n} * Tap value for each section / 105 ……… (7) where TD is the value in the transformer. Voltage drop (1.6 is standard). TRD: voltage drop directly below the transformer (1.0 is standard). LWD: Voltage drop at the end of the low voltage line (6.0 as standard). m: 6 for a normal section and 10 for a specific section. n: Voltage check correction value.

Generally, in Article 26 of the Electricity Business Act and Article 25 of the Regulations on Construction of the Electricity Business Act, at the supply point, the electric power company must supply 101 V ± 6 V (part (101 + m) of the formula (4)) when supplying 100 V. There are obligations to hold. In addition, since the voltage drop is not taken into account as it is, correction is made by adding the voltage drop ((TD + TRD) in equation (4)).
Part). Note that n is given by the following equation.

[Mathematical formula-see original document] n = (bank current used for flexibility calculation) / annual maximum current of bank (≦ 1) multiplied by a constant part ((tap value for each section / 105) part of equation (4)) Calculate as allowable voltage value.

Next, the calculation of the number of deviating consumers in step S44 will be described. When the voltage value exceeds the allowable voltage value for the normal section, the number of deviating consumers is calculated. At this time, if both the upper limit deviation and the lower limit deviation occur, both the upper limit deviation and the lower limit deviation are calculated. However,
When the voltage value is compared with the allowable voltage value for the specific section, if the voltage value exceeds the allowable voltage value for the specific section, the calculation is stopped. It is assumed that the number of consumers in the section is evenly distributed along the main high voltage line, and that the number of customers from immediately below the transformer to the low voltage terminal is evenly distributed along the low voltage line.

At this time, the number of deviating consumers is as shown in FIG. If A, B, C, and D exist outside V ₁ -V ₂ in FIG. 7, it is determined that there is a deviating customer. In FIG. 7, V ₁ is the power supply-side switch voltage value, V ₂ is the load-side switch voltage value, C _o is the number of customers deviating from the upper limit, C _b is the number of normal customers,
A is the upper limit of the allowable voltage (directly below the transformer), B is the lower limit of the allowable voltage (directly below the transformer), C is the upper limit of the allowable voltage (low voltage line end), and D is the lower limit of the allowable voltage (low voltage line end). ).
Further, the total number of consumers _Ca and the designated section voltage width are as follows.

[Equation 6] Total number of consumers C _a = C _o + C _b (V ₁ −V ₂ ) The area surrounded by the specified section voltage width = A, S, C, D

That is, the number of customers in one section from the switch to the switch is represented by a portion surrounded by the power supply-side switch voltage V ₁ and the load-side switch voltage V _2, and (4) to ( 7) The number of customers who deviate from the permissible value indicates the part that protrudes from the part surrounded by the voltage values (A, B, C, D) obtained from the equation.
If D ≦ V ₁ , V ₂ ≦ A, there is no customer who has deviated, and several upper limit departure patterns are conceivable (in the case of lower limit departure, reverse). FIG. 7 illustrates the upper limit deviation condition 1 (A <V ₁ ≦ C and V ₂ ≦ A). At this time, the number of deviating customers is expressed by the following equation.

C _o = C _a * 0.5 * (V ₁ -A) ² / ((C−A) * (V ₁ -V ₂ )) (8) Calculate the number of deviating customers by substituting.

Expression (8) is generated as follows.
7, the intersection of the extension line and the V ₁ of the AB P, AC
The intersection of the V ₁ Q, and the intersection between the DC and the V ₁ and R and,

PA = (V ₁ −A), CR = (C−V ₁ ) Also, since ΔAPQ and ΔCRQ are similar,

AP: CR = PQ: RQ = (V ₁ −A) :( C−V ₁ ) Since PR = PQ + RQ = (CA),

[Equation 10] Further, the total customer number because it is (C-A) × (V 1 -V 2), departing customer number eventually, since the ratio of C _o occupying the C _a,

[Equation 11] Becomes

FIG. 8 is a diagram showing a calculation example of the number of customers who exceed the upper limit. When the voltage value exceeds the allowable voltage upper limit, the number of customers who exceed the upper limit is calculated according to the following condition (V ₁ <in the case of V ₂ may replace the value of V ₁ <V _2). Although various conditions can be considered, FIG.
(A) is A <V ₁ ≦ C AND V ₂ ≦ A,
In this case, the upper limit deviating customer number _Co is:

It is [number 12] _{C o = C a * 0.5 (} V 1 -A) 2 / ((C-A) * (V 1 -V 2)).

Similarly, FIG. 8B shows A <V ₁ ≦ = CAN.
DA <V ₂ <V ₁ ,

Equation 13] C _o = C _a * is _{(0.5 (V 1 + V 2} ) -A) / (C-A). Similarly, FIG. 8C shows A <V ₁ <C AND V
A ₁ = V _2,

[The number 14 is a _{C o = C a * (V} 1 -A) / (C-A).

Next, the determination of a solution in steps S46 and S49 will be described. A solution is determined according to the already calculated voltage value of the switch point, the allowable voltage value, and the number of customers who have deviated from the allowable value. There are two types of solutions for the optimum bank transmission voltage adjustment in the present invention:... The optimum solution and... The best solution, and the determination of each solution will be described. Judgment of optimal solution: When the obtained voltage value satisfies the following condition, it is determined as an optimal solution. Condition: Voltage values in all sections to be processed do not exceed allowable voltage values (upper / lower limit values) for normal sections. Judgment of the best solution: If the obtained solution is not the optimal solution,
If the current solution is better than the previous solution based on the next best solution evaluation criterion, the current solution is newly stored as the best solution. Best Solution Evaluation Criteria: Minimum number of deviating customers.

However, if the number of deviating consumers has not decreased from the previous solution, the recalculation process is terminated. Also, L
If the optimal solution is not found as a result of recalculation by R tap elevation, the data finally stored as the optimal solution is determined as the solution for the optimal bank transmission voltage adjustment. As described above, according to the above-described embodiment, the load fluctuation data is collected in a short cycle, the optimum bank transmission voltage value is calculated, and the LR tap control is performed, so that the voltage of each home can be always kept constant. It becomes possible.

[0026]

As described above, according to the present invention, it has become possible to reduce a great amount of time and labor required for adjusting the bank sending voltage. In addition, since the state of the distribution line is constantly monitored and the bank voltage is adjusted,
Even if the load fluctuated, it was possible to respond quickly and to cope with this.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a transmission voltage adjustment processing device according to the present invention.

FIG. 2 is a detailed diagram of an optimum bank transmission voltage adjustment processing device.

FIG. 3 is a flowchart of the entire process of the present invention.

FIG. 4 is a flowchart of calculating an optimum bank transmission voltage adjustment value.

FIG. 5 is an explanatory diagram of a passing current of each switch.

FIG. 6 is an explanatory diagram of a voltage value at each switch point.

FIG. 7 is an explanatory diagram of the number of deviating consumers.

FIG. 8 is a diagram showing a calculation example of the number of customers who have exceeded the upper limit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 TM master station 2 TC master station 1-1 TM slave station 2-1 TC slave station 1-2 Distribution circuit breaker 1-3 Current transformer 3,3-1 Switch 10 Transmission voltage adjustment processing device 11 Data input means 12 System information storage means 13 Optimum value calculation means 14 Bank control means 21 Load fluctuation data input device 22 Power distribution system database 23 Optimum pattern transmission voltage calculation means 24 Bank LR control device

Claims (1)

(57) [Claims] An electric information of a distribution system connected to a circuit breaker for distribution lines and divided into a plurality of sections by a switch is transmitted to a remote location.
Uptake via the monitoring control device, electrostatic supplied to the customers connected to the distribution system of the electrical information on the basis
In sending voltage adjusting apparatus for adjusting the pressure, the electrical
Information is distribution line current value, bank voltage value, and section switching
Load fluctuation data including the voltage and current values of the
Information on the distribution system equipment and load, and how each equipment
System information storage that stores information indicating whether the
Means, the load fluctuation data and the system information storage means.
Based on the information stored in the distribution system.
Optimal value calculating means for calculating an optimal voltage value of the bank to be used;
The bank voltage is calculated based on the calculation result of the optimum value calculation means.
And bank control means for controlling.
Transmission voltage adjustment processing device in distribution system.