JP6151137B2 - Ultimate voltage estimation device and estimation program - Google Patents

Description

  Embodiments described herein relate generally to an arrival voltage estimation device and an estimation program that estimate an arrival voltage to a consumer.

  Currently, in power systems, it is common to transmit large amounts of power to demand areas in urban areas for relatively long distances due to the expansion of demand scale, remote power supply, uneven distribution, and expansion of wide area operations. ing. On the other hand, in addition to inductive loads and capacitive loads, in recent years, the number of cases where distributed power sources (solar power generation, wind power generation, etc.) are provided is increasing.

  In general, a power system is required to have a function of maintaining a voltage at a monitoring point within an allowable range and suppressing transmission loss to a small value. For this reason, the monitoring point is equipped with a measuring instrument, and the reactive power of the generator, the transformer tap, the phase adjuster, and the like are controlled based on the information obtained by the measurement. According to this, the voltage at the monitoring point is controlled so as to keep it within an allowable range, but the voltage reached to a point other than the monitoring point (for example, a customer) cannot be grasped in detail. Detailed understanding of the voltage reached to the customer is considered to be an important premise for stable and high-quality power supply.

JP 2012-19638 A JP 2011-229267 A

  An object of this invention is to provide the ultimate voltage estimation apparatus and estimation program which can estimate the ultimate voltage to the consumer without a measuring instrument.

  The ultimate voltage estimation apparatus of the embodiment has the following first to seventh means. The first means includes a first measuring instrument that measures the voltage, current, and power factor provided on the upstream side of the transmission line connected to the plurality of consumers when viewed from the plurality of consumers. The first voltage that is the value of the first current, the first current that is the value of the current, and the first power factor that is the value of the power factor. The second means is a value of the voltage from a second measuring instrument that measures the voltage, current, and power factor provided on the downstream side of the power transmission line as viewed from the plurality of consumers. A voltage of 2, a second current that is the value of the current, and a second power factor that is the value of the power factor are captured. Third means, based on the first voltage, the first current, and the first power factor, a first tide that is a tide in the first measuring instrument of the transmission line, Based on the second voltage, the second current, and the second power factor, a second tidal current that is a tidal current at the second measuring instrument of the transmission line is further changed to the first tidal current. And based on this 2nd tidal current, the total load electric power consumed between the said 1st measuring device and the said 2nd measuring device is each calculated. The fourth means virtually allocates the total load power and initially sets the set load power for each of the plurality of consumers. The fifth means includes line information between the first measuring instrument and the second measuring instrument of the transmission line, the set load power of each of the plurality of consumers, the first voltage, and the Using the second tidal current, a third tidal current that is a tidal current estimated by the first measuring instrument and an estimated ultimate voltage that is an estimated ultimate voltage for each of the plurality of consumers are calculated. The sixth means determines whether or not a difference between the first tidal current and the third tidal current is within a preset threshold. When the difference is not within the threshold, the seventh means adjusts, resets, and updates the set load power of each of the plurality of consumers based on the difference.

The functional block diagram which shows the structure of the ultimate voltage estimation apparatus of Embodiment 1 with an estimation target object. The system configuration | structure figure which shows typically the estimation target object shown in FIG. The flowchart which shows operation | movement of the ultimate voltage estimation apparatus shown in FIG. The functional block diagram which shows the structure of the ultimate voltage estimation apparatus of Embodiment 2 with an estimation target object. FIG. 5 is a system configuration diagram schematically showing the estimation object shown in FIG. 4. The functional block diagram which shows the structure of the ultimate voltage estimation apparatus of Embodiment 3 with an estimation target object. FIG. 7 is a system configuration diagram schematically showing the estimation object shown in FIG. 6. The functional block diagram which shows the structure of the ultimate voltage estimation apparatus of Embodiment 4 with an estimation target object. The functional block diagram which shows the structure of the ultimate voltage estimation apparatus of Embodiment 5 with an estimation target object. The flowchart which shows operation | movement of the ultimate voltage estimation apparatus shown in FIG. The functional block diagram which shows the structure of the ultimate voltage estimation apparatus of Embodiment 6 with an estimation target object. The functional block diagram which shows the structure of the ultimate voltage estimation apparatus of Embodiment 7 with an estimation target object. FIG. 10 is a functional block diagram illustrating a configuration of an ultimate voltage estimation device according to an eighth embodiment.

(Embodiment 1)
Based on the above, the ultimate voltage estimation device of the embodiment will be described below with reference to the drawings. FIG. 1 shows the configuration of the ultimate voltage estimation apparatus according to the first embodiment together with an estimation object. First, the configuration of the estimation object will be described.

  The power source 11 is various power plants (generators). Electric power is sent from the power supply 11 to the branch system transformer 13 via the backbone bus 12. Further, the voltage is stepped down by the transformer 13, and power is sent to the branch system areas 1, 2,... Via the branch system bus 14 by the transmission lines 1a, 2a,. In each branch area 1, 2,..., A measuring instrument 1b is provided on the upstream side thereof, and a plurality of consumers 21, 22, 23 that receive power supply by a power transmission line 1d on the downstream side of the measuring instrument 1b. , ... exists. A measuring instrument 1c is provided on the downstream side of the consumers 21, 22, 23,... Of the power transmission line 1d, and a distribution system bus 1e is connected to the downstream side of the measuring instrument 1c. When viewed from the branch system bus 14, each branch system area 1, 2,... Exists radially.

  The measuring instruments 1b and 1c measure voltage, current, and power factor. That is, if it is branch system area 1, the voltage transmitted by the transmission line 1a (1d) to the measuring instrument 1b (1c) flows from the transmission line 1a (1d) to the transmission line 1d (distribution system bus 1e). Measure the current and the power factor of these voltages and currents. Data as these measurement results is sent to the ultimate voltage estimating apparatus of the first embodiment through the dedicated communication line 15.

  Note that these data are generally collected by a configuration (not shown), and are used to maintain the voltages in the measuring instruments 1b, 1c, etc. within an allowable range and to reduce power transmission loss. That is, it is used as information for controlling reactive power of the power plant 11, a tap of a transformer such as the transformer 13, a phase adjuster (not shown), and the like. As a result, the voltages at the measuring instruments 1b and 1c (monitoring points) are kept within an allowable range as long as the control is normal. However, it is not possible to grasp in detail the voltage reached to the consumers 21, 22, 23,. Therefore, an ultimate voltage estimation device (reference numerals 51 to 59) is provided as shown in the figure for grasping this.

  As shown in FIG. 1, this ultimate voltage estimating device includes a measurement result capturing unit 51, an upstream tidal current / downstream tidal current / total load power calculating unit 52, a setting load power initial setting unit for each consumer, and resetting. Update unit 53, initial setting coefficient storage holding unit 54, upstream power flow / arrival voltage estimation calculation unit 55, line information storage storage unit 56, difference evaluation judgment unit 57 between upstream power flow measurement value and estimated value, estimated arrival A voltage memory holding unit 58 and a convergence coefficient memory holding unit 59 are provided.

  Hereinafter, these functional blocks may be abbreviated as follows for convenience of explanation. That is, the capturing unit 51, the calculating unit 52, the initial setting unit 53 (the resetting update unit 53 in some cases), the storage holding unit 54, the estimation calculating unit 55, the storage holding unit 56, the difference evaluation judging unit 57, the storage holding unit 58, A storage holding unit 59.

  Before describing the ultimate voltage estimation device in detail, the configuration of the estimation object assumed here will be further described with reference to FIG. In FIG. 2, the reference numerals in the figure are associated with those given in the configuration shown in FIG.

  The measuring instrument 1b measures the voltage Va, the current Ia, and the power factor cos θa (measured per single phase). These measurement results are sent to the capturing unit 51 (FIG. 1) via the dedicated communication line 15. The measuring instrument 1c measures the voltage Vb, the current Ib, and the power factor cos θb (measured per single phase). These measurement results are also sent to the capturing unit 51 (FIG. 1) via the dedicated communication line 15.

  The consumer 21 is a consumer who consumes the load active power PL1 and the load reactive power QL1. The ultimate voltage VL1 that is the voltage when the consumer 21 is reached is one target value to be estimated. Similarly, the consumer 22 is a consumer who consumes the load active power PL2 and the load reactive power QL2. The arrival voltage VL2 that is a voltage when reaching the customer 22 is also one target value to be estimated. Furthermore, the consumer 23 is a consumer who consumes the load active power PL3 and the load reactive power QL3. The ultimate voltage VL3, which is the voltage when reaching the consumer 23, is also one target value to be estimated. The same applies to the case where there are further consumers to be fed by the power transmission line 1d. In the following description, it is assumed that the consumers 21, 22 and 23 exist between the measuring instruments 1b and 1c.

  Returning to FIG. 1, the capturing unit 51 captures the voltage Va, current Ia, power factor cos θa, and voltage Vb, current Ib, power factor cos θb via the dedicated communication line 15. These acquired values are sent to the calculation unit 52.

The calculation unit 52 uses the upstream voltage Va, current Ia, and power factor cos θa sent to calculate the upstream power flow (effective component) Pa as Pa = 3VaIa · cos θa.
It is calculated by the following formula. Similarly, based on the voltage Va, the current Ia, and the power factor cos θa, the upstream power flow (invalid component) Qa is set to Qa = 3 VaIa · sin θa
It is calculated by the following formula. The reason why the value on the right side of these equations is three times is that the measurement is performed for a single phase, so that it is converted into three phases.

The calculation unit 52 also uses the downstream voltage Vb, the current Ib, and the power factor cos θb that have been sent, and converts the downstream power flow (effective component) Pb to Pb = 3VbIb · cos θb.
It is calculated by the following formula. Similarly, based on the voltage Vb, current Ib, and power factor cos θb, the downstream power flow (invalid component) Qb is expressed as Qb = 3VbIb · sin θb
It is calculated by the following formula. The reason why the value on the right side of these equations is three times is the same as described above.

  Further, the calculation unit 52 calculates equations Pa-Pb and Qa-Qb using the obtained upstream currents Pa and Qa and downstream currents Pb and Qb, respectively, and consumes between the measuring instrument 1b and the measuring instrument 1c. The total load power P (= Pa−Pb) and Q (= Qa−Qb) are calculated. The total load power P, Q includes the loss Ploss, Qloss generated between the measuring instrument 1b and the measuring instrument 1c in addition to the power consumed by the consumers 21, 22, 23. (Such as a loss in the transmission line 1d and a loss in a transformer (not shown)). The calculated total load powers P and Q are sent to the initial setting unit 53. The calculation unit 52 also sends the voltage Va at the measuring instrument 1b, the upstream power flows Pa and Qa, and the downstream power flows Pb and Qb to the initial setting unit 53.

  The initial setting unit 53 initially sets the set load power (set load active power and set load reactive power) for each of the consumers 21, 22, and 23 based on the total load power P and Q that have been sent. That is, since the load power (PL1, QL1, etc.) for each of the consumers 21, 22, 23 is unknown (cannot be measured in real time), the total load power P, Q is appropriately set to each customer 21. , 22, and 23. As an initial setting coefficient for this purpose, a coefficient held in the storage holding unit 54 for that purpose is used. Specifically, the initial setting coefficient can be set to a value reflecting past load power allocation results of the customers 21, 22, and 23 as a device for further speeding up the subsequent convergence.

Assuming that the initial setting coefficients related to the effective power of the consumers 21, 22, and 23 are αPL1, αPL2, and αPL3, respectively, the set load active powers PL1, PL2, and PL3 of the consumers 21, 22, and 23 are respectively PL1 = P · (ΑPL1 / (αPL1 + αPL2 + αPL3))
PL2 = P · (αPL2 / (αPL1 + αPL2 + αPL3))
PL3 = P · (αPL3 / (αPL1 + αPL2 + αPL3))
It becomes. In general, PLi = P · (αPLi / ΣαPLi).

Further, assuming that the initial setting coefficients regarding the reactive power of the consumers 21, 22, and 23 are αQL1, αQL2, and αQL3, respectively, the set load reactive powers QL1, QL2, and QL3 of the consumers 21, 22, and 23 are respectively QL1 = Q · (αQL1 / (αQL1 + αQL2 + αQL3))
QL2 = Q · (αQL2 / (αQL1 + αQL2 + αQL3))
QL3 = Q · (αQL3 / (αQL1 + αQL2 + αQL3))
It becomes. In general, QLi = Q · (αQLi / ΣαQLi).

  When the initial setting is completed, the set load power (set load active power PL1 to PL3 and set load reactive power QL1 to QL3) for each of the consumers 21, 22, and 23 is sent to the estimation calculation unit 55. The initial setting unit 53 also sends the voltage Va in the measuring instrument 1b, the upstream power flow Pa, Qa, and the downstream power flow Pb, Qb sent from the calculation unit 52 to the estimation calculation unit 55.

  In addition to the set load active powers PL1 to PL3 and the set load reactive powers QL1 to QL3, the voltage Va at the measuring instrument 1b, and the downstream power flows Pb and Qb, the estimation calculating unit 55 measures the measuring instrument 1b of the transmission line 1d. And the measuring device 1c, the estimated currents Pae and Qae of the measuring device 1b and the estimated reaching voltages VL1e and VL2e that are the estimated reaching voltages of the plurality of consumers 21, 22, and 23, respectively. , VL3e is calculated (tidal flow calculation). For the track information, information stored in the track information storage / holding unit 56 in advance is used. The line information includes the impedance of the line to each of the consumers 21, 22, 23 between the measuring instruments 1b, 1c, and the information if a transformer exists between them. Specifically, numerical calculations such as the well-known Newton-Raphson method can be used for the tidal current calculation.

  The estimation calculation unit 55 calculates the estimated arrival voltages VL1e, VL2e, and VL3e obtained by the power flow calculation, the upstream power flows Pae and Qae, and the upstream power flows Pa and Qa (that is, values obtained by actual measurement). This is sent to the difference evaluation judgment unit 57. The difference evaluation judgment unit 57 determines whether the value of | Pa−Pae | is within a predetermined threshold value εp or the value of | Qa−Qae | It is determined whether it is within the threshold value εq.

  When | Pa−Pae | ≦ εp and | Qa−Qae | ≦ εq, the difference evaluation determination unit 57 determines that the estimated arrival voltages VL1e, VL2e, and VL3e at that time are accurately estimated voltages. Judgment is made, and these values are recorded in the estimated ultimate voltage storage / holding unit 58. In other words, the upstream power flow calculation is performed using the set load power (set load active power and set load reactive power) virtually set for the consumer, and the result of the power flow calculation is the value obtained by actual measurement. This is because the distribution of the set load power for each of the consumers 21, 22, and 23 is considered not to be significantly different from the actual.

  If it cannot be said that | Pa−Pae | ≦ εp and | Qa−Qae | ≦ εq, the difference evaluation determination unit 57 performs virtual distribution of the set load power for each of the consumers 21, 22, and 23. Therefore, this is notified to the resetting update unit 53. At that time, the numerical values of the differences Pa-Pae and Qa-Qae are also transmitted.

The resetting update unit 53 adjusts, resets and updates the set load power of each of the plurality of consumers 21, 22, and 23 based on the differences Pa−Pae and Qa−Qae. The formula for updating is
PLi = PLi + βPLi · (Pa−Pae) (αPLi / ΣαPLi)
QLi = QLi + βQLi · (Qa−Qae) (αQLi / ΣαQLi)
(I = 1 to 3). Here, βPLi and βQLi are convergence coefficients and are constants greater than 0 and less than or equal to 1, respectively. As the convergence coefficients βPLi and βQLi, coefficients previously held in the convergence coefficient storage holding unit 59 are used.

  When the resetting is completed, the resetting update unit 53 estimates and calculates the new set load power (set load active power PL1 to PL3 and set load reactive power QL1 to QL3) for each of the consumers 21, 22, and 23. Send to part 55. And the operation | movement in the estimation calculation part 55 or less is as having already demonstrated. That is, the operation of a loop formed by the resetting update unit 53, the estimation calculation unit 55, and the difference evaluation determination unit 57 is cascaded by | Pa−Pae | ≦ εp and | Qa−Qae | ≦ in the difference evaluation determination unit 57. The process ends when it is determined that εq, and at that time, the estimated reaching voltage storage holding unit 58 holds the estimated reaching voltages VL1e, VL2e, and VL3e that are considered to be accurately estimated.

  As described above, according to this embodiment, it is possible to estimate the arrival voltage to the consumers 21, 22, and 23 without the measuring instrument as the estimated arrival voltages VL1e, VL2e, and VL3e with high accuracy. The operation of the ultimate voltage estimating apparatus according to the first embodiment described above is shown as a flowchart in FIG. In FIG. 3, subtracting 100 from the code of each step corresponds to the code of each functional block shown in FIG. When two or more steps correspond to each functional block in FIG. 1, suffixes a, b,... Are added to the reference numerals in the steps in FIG. FIG. 3 can be easily understood from the contents described above with reference to FIGS.

(Embodiment 2)
Next, the ultimate voltage estimation apparatus of Embodiment 2 is demonstrated with reference to FIG. FIG. 4 shows the configuration of the ultimate voltage estimation apparatus according to the second embodiment together with the estimation object. In this figure, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted unless there are points to be added. This embodiment assumes a case where each of the plurality of consumers 21A, 22A, and 23A has a distributed power source (such as solar power generation).

  When distributed power sources are introduced in this way, especially when a large amount is introduced, using the apparatus shown as the first embodiment, the estimated ultimate voltages VL1e, VL2e, VL3e of the consumers 21, 22, 23 are used. Is expected to be obtained as a less accurate value. In other words, what is obtained is an estimated value in which the power output from the distributed power source is not taken into account at all, and the component considered as a target is separated from the actual state.

  Therefore, in the second embodiment, in consideration of the actual situation, the power output from the distributed power source is also distributed to the plurality of consumers 21A, 22A, and 23A by performing initial setting and re-setting update. It is assumed that the power output from the distributed power source has a premise that its power factor is 1.

  As shown in FIG. 4, this ultimate voltage estimating apparatus is different from the configuration shown in FIG. 1 in that the set load reactive power initial setting unit / reset updating unit 53A and convergence coefficient storage holding unit 59A for each consumer. , Setting load active power calculation setting unit 61 for each consumer, power factor storage holding unit 62, calculation setting unit 63 for total power of distributed power source, initial setting coefficient storage holding unit 64, setting power source active power for each consumer Initial setting unit / resetting update unit 65, convergence coefficient storage holding unit 66, upstream power flow / arrival voltage estimation calculation unit 55A.

  Hereinafter, these functional blocks may be abbreviated as follows for convenience of explanation. That is, the initial setting unit 53A (reset update unit 53A in some cases), the storage holding unit 59A, the calculation setting unit 61, the storage holding unit 62, the calculation setting unit 63, the storage holding unit 64, and the initial setting unit 65 (reset in some cases) Update unit 65), storage holding unit 66, and estimation calculation unit 55A.

  Before describing this ultimate voltage estimation device in detail, the configuration of the estimation object assumed here will be described with reference to FIG. In FIG. 5, the reference numerals in the figure are associated with those given in the configuration shown in FIG. 4.

  FIG. 5 shows that each consumer 21A, 22A, and 23A outputs power source active power PV1, PV2, and PV3 as a difference from that shown in FIG. The other points are the same as those shown in FIG. That is, the consumer 21A is a consumer who consumes the load active power PL1 and the load reactive power QL1 and outputs the power source active power PV1. The reached voltage VL1 to the consumer 21A is one target value to be estimated. The same applies to the customers 22A and 23A.

Returning to FIG. 4, the description will be continued. The capturing unit 51 and the calculating unit 52 are the same as those in FIG. Next, the initial setting unit 53A initializes and distributes the set load reactive power for each consumer as described above. That means
QLi = Q · (αQLi / ΣαQLi)
It is distributed as an initial setting by the formula of The set load active power for each customer is calculated by using the set load reactive power QLi and a predetermined power factor (for example, 0.95) in the calculation setting unit 61 which is the next functional block. Here, the power factor used in the memory holding unit 62 is used. The calculation formula is based on the definition of power factor.
PLi = (Qi · Power factor) / √ (1−Power factor ² )
It is.

Next, the calculation setting unit 63 calculates and sets the total power source effective power Ppv of the distributed power source. The formula for this is
Ppv = P-ΣPLi
It is. In other words, the total load active power P is subtracted from the sum of the plurality of consumers 21A, 22A, and 23A of the set load active power PLi, and the distributed power source existing between the measuring instrument 1b and the measuring instrument 1c is output. The total power is calculated and set as the total power source effective power Ppv. The calculated total power source effective power Ppv of the distributed power source is sent to the initial setting unit 65.

The initial setting unit 65 distributes this as an initial setting to the consumers 21A, 22A, and 23A based on the total power source effective power Ppv sent. The formula is
PLpvi = Ppv · (αPLpvi / ΣαPLpvi)
It is. As the initial setting coefficient αPLpvi for this purpose, a coefficient held in the storage holding unit 64 for that purpose is used. Specifically, the initial setting coefficient αPLpvi can be set to a value reflecting the ratio of the rated output of the distributed power sources of the consumers 21A, 22A, and 23A as a device for making the subsequent convergence faster.

  Next, the estimation calculation unit 55A includes the set load reactive powers QL1 to QL3, the set load active powers PL1 to PL3, the set power source active powers PLpv1 to PLpv3, and the measuring instrument 1b for each of the plurality of consumers 21A, 22A, and 23A. In addition to the voltage Va and downstream currents Pb and Qb, using the line information between the measuring instrument 1b and the measuring instrument 1c of the electric wire 1d, the estimated tidal currents Pae and Qae in the measuring instrument 1b and a plurality of consumers Estimated ultimate voltages VL1e, VL2e, and VL3e at 21, 22, and 23 are calculated (power flow calculation).

  The determination operation in the next difference evaluation determination unit 57 is the same as that described in FIG. Then, if it cannot be said that | Pa−Pae | ≦ εp and | Qa−Qae | ≦ εq, the difference evaluation determining unit 57 virtually sets the set load reactive power for each of the consumers 21A, 22A, and 23A. In order to redo the distribution, this is notified to the resetting update unit 53A. At that time, the numerical values of the differences Pa-Pae and Qa-Qae are also transmitted.

Based on the difference Qa−Qae, the resetting update unit 53A adjusts, resets, and updates the set load reactive power of each of the plurality of consumers 21A, 22A, 23A. The formula for updating is
QLi = QLi + βQLi · (Qa−Qae) (αQLi / ΣαQLi)
(I = 1 to 3). Here, βQLi is a convergence coefficient as already described with reference to FIG. 1, and is a constant greater than 0 and equal to or less than 1. As the convergence coefficient βQLi, a coefficient held in advance in the convergence coefficient storage holding unit 59A is used.

  When the resetting is completed, the resetting updating unit 53A sends the new set load reactive powers QL1 to QL3 for each of the consumers 21A, 22A, and 23A to the estimation calculating unit 61. The operations in the calculation setting unit 61 and the next calculation setting unit 63 are as described above.

The next operation in the resetting update unit 65 is to adjust and reset the set power source active power PLpvi of each of the plurality of consumers 21A, 22A, and 23A based on the difference Pa-Pae. The formula for that is
PLpvi = PLpvi + βPLi · (Pa−Pae) (αPLpvi / ΣαPLpvi)
(I = 1 to 3). Here, βPLi is a convergence coefficient as already described in FIG. 1, and is a constant greater than 0 and equal to or less than 1. As the convergence coefficient βPLi, a coefficient held in advance in the convergence coefficient storage holding unit 58 is used.

  When the above-described resetting is completed, the setting update unit 65 sets the new set load power (set load active power PL1 to PL3 and set load reactive power QL1 to QL3) and the set power source valid for each of the consumers 21, 22, and 23. The powers PLpv1 to PLpv3 are sent to the estimation calculation unit 55A. And the operation | movement in the estimation calculation part 55A or less is as having already demonstrated. That is, the operation of the loop formed by cascaded the resetting update unit 53A, the calculation setting unit 61, the calculation setting unit 63, the resetting update unit 65, the estimation calculation unit 55A, and the difference evaluation determination unit 57 is the difference evaluation determination unit. 57 is finished when it is determined that | Pa−Pae | ≦ εp and | Qa−Qae | ≦ εq, and the estimated reaching voltage that is considered to have been accurately estimated at the estimated reaching voltage storage holding unit 58 at that time. VL1e, VL2e, and VL3e are held.

  As described above, according to this embodiment, the voltage reached to the consumers 21A, 22A, and 23A without the measuring instrument, and the consumers 21A, 22A, and 23A have the distributed power source. Under the premise, it can be estimated with high accuracy as the estimated reached voltages VL1e, VL2e, VL3e. It should be noted that expressing the operation of the apparatus shown in FIG. 4 as a flowchart can be easily performed according to FIG.

(Embodiment 3)
Next, the ultimate voltage estimation apparatus of Embodiment 3 is demonstrated with reference to FIG. FIG. 6 shows the configuration of the ultimate voltage estimation apparatus according to the third embodiment together with the estimation object. In the figure, the same components as those shown in the already described drawings are denoted by the same reference numerals, and description thereof will be omitted unless there is a point to be added. In this embodiment, it is assumed that the plurality of consumers 21A and 23A each have a distributed power source. In particular, the reactive power component Qa of the power flow in the measuring instrument 1b is very close to zero. This is a device that can cope with the situation.

  Thus, the situation where the reactive power component Qa of the upstream power flow is very close to zero is when the output of the distributed power source possessed by the plurality of consumers 21A, 23A is relatively large (for example, non-operating days) This can occur when the load powers PLi and QLi are very small and the amount of photovoltaic power generation is increased in fine weather. In such a case, as described in the second embodiment, the initial setting for distributing the set load reactive power cannot be performed first.

  Therefore, the third embodiment generally operates as follows. That is, the load active power PL of a representative customer 22 that is fed by the transmission line 1d is first grasped, and based on this, the set load active power is provisionally set for the other customers 21A and 23A. . Next, the set load reactive power is calculated and set for 21A and 23A of other consumers using the temporarily set load active power. Further, the total power output from the distributed power source existing between the measuring instrument 1b and the measuring instrument 1c is obtained by subtracting the total sum of the plurality of consumers 21A and 23A of the set load effective power from the total load active power P. Calculate and set. This total power is distributed and provisionally set to each of the consumers 21A and 23A.

  In the following description, it is assumed that the representative customer 22 does not have a distributed power source, and preferably, the measuring device 31 is installed in the representative consumer 22 and at least the load active power (hereinafter referred to as the load active power). , Representative load active power) is assumed to be grasped based on the measurement. In this case, the measuring instrument 31 is connected to the dedicated communication line 15, and the dedicated communication line 15 can bring the representative load active power to the measurement result capturing unit 51 </ b> A. Even if the measuring instrument 31 does not exist in this manner, if there is a consumer who operates as expected, the consumer is treated as a representative consumer and the predicted representative load active power is measured. The result capturing unit 51A can be used instead of the information obtained from the measuring instrument 31.

  As shown in FIG. 6, this ultimate voltage estimating device is different from any of the functional blocks shown in FIGS. 1 and 4 in that a measurement result capturing unit 51A, a temporary setting unit for setting load active power for each consumer, Resetting / updating unit 53B, provisional setting coefficient storage / holding unit 54A, convergence coefficient storage / holding unit 59B, calculation / setting unit 61A for setting load reactive power for each consumer, power factor storage / holding unit 62A, and setting power source active power for each consumer Provisional setting unit 65A, temporary setting coefficient storage holding unit 64A, upstream power flow / arrival voltage estimation calculation unit 55B, and control unit 71.

  Hereinafter, these functional blocks may be abbreviated as follows for convenience of explanation. That is, the capturing unit 51A, temporary setting unit 53B (reset update unit 53B in some cases), storage holding unit 54A, storage holding unit 59B, calculation setting unit 61A, storage holding unit 62A, temporary setting unit 65A, storage holding unit 64A, This is an estimation calculation unit 55B.

  Before describing this ultimate voltage estimation device in detail, the configuration of the estimation object assumed here will be described with reference to FIG. In FIG. 7, the reference numerals in the figure are associated with those given in the configuration shown in FIG. 6.

  FIG. 7 differs from the one shown in FIG. 5 in that the representative customer 22A does not have a distributed power source and has a measuring instrument 31 that can obtain at least the load active power PL2. It shows that. The other points are the same as those shown in FIG. That is, the consumer 21A is a consumer who consumes the load active power PL1 and the load reactive power QL1 and outputs the power source active power PV1. The reached voltage VL1 to the consumer 21A is one target value to be estimated. The same applies to the consumer 23A. The reached voltage VL <b> 2 at the representative customer 22 is excluded from the estimation target when it can be known by the measuring instrument 31.

  Returning to FIG. 6, the capturing unit 51 </ b> A grasps the representative load active power PL <b> 2 in the representative customer 22 in this functional block as a new function. Other than that, it has the same function as the capturing unit 51 in FIGS. The next calculation unit 52 is the same as described with reference to FIGS.

Next, the temporary setting unit 53B temporarily sets and distributes the set load active power for each customer. That means
PLi = PL2 · (αPLi / αPL2)
(I = 1, 3). Here, the load active power PL2 of the representative customer 22 is a value that has already been grasped as described above, and a coefficient held in the storage holding unit 54A is used as the temporary setting coefficient αPLi (i = 1 to 3). Specifically, the temporary setting coefficient can be a value reflecting past load power allocation results of the consumers 21A, 22, and 23A as a device for further speeding up the subsequent convergence.

Next, in the calculation setting unit 61A, the set load reactive power QLi for each consumer is calculated using the set load reactive power PLi and a predetermined power factor (for example, 0.95). Here, the power factor held by the memory holding unit 62A is used. The calculation formula is based on the definition of power factor.
QLi = (PLi / power factor) · √ (1−power factor ² )
It is. Subsequently, the calculation setting unit 63 calculates and sets the total power source effective power Ppv of the distributed power source. The formula for this is
Ppv = P-ΣPLi
It is. The calculation setting unit 63 is the same as that described in FIG. The calculated total power source effective power Ppv of the distributed power source is sent to the initial setting unit 65A.

Next, the initial setting unit 65A distributes this as a temporary setting to the consumers 21A and 23A based on the total power supply effective power Ppv sent thereto. The formula is
PLpvi = Ppv · (αPLpvi / ΣαPLpvi)
(However, PLpv2 is 0 from the point already described.) As the temporary setting coefficient αPLpvi for this purpose, a coefficient held in the storage holding unit 64A for that purpose is used. Specifically, the temporary setting coefficient αPLpvi can be set to a value reflecting the ratio of the rated outputs of the consumers 21A and 23A as a device for further speeding up the subsequent convergence.

  Next, the estimated calculation unit 55B includes the set load active powers PL1 to PL3, the set load reactive powers QL1 to QL3, and the set power source active powers PLpv1 and PLpv3, and the measuring instrument 1b for each of the plurality of consumers 21A, 22, and 23A. In addition to the voltage Va and downstream currents Pb and Qb, using the line information between the measuring instrument 1b and the measuring instrument 1c of the electric wire 1d, the estimated tidal currents Pae and Qae in the measuring instrument 1b and a plurality of consumers Estimated ultimate voltages VL1e and VL3e in 21A and 23A are calculated (power flow calculation).

  The determination operation in the next difference evaluation determination unit 57 is the same as that described with reference to FIGS. Then, if it cannot be said that | Pa−Pae | ≦ εp and | Qa−Qae | ≦ εq, the difference evaluation determination unit 57 performs virtual distribution of the set load active power for each of the consumers 21A and 23A. In order to start over, this is notified to the resetting update unit 53B. At that time, the numerical values of the differences Pa-Pae and Qa-Qae are also transmitted.

The reset update unit 53B adjusts, resets, and updates the set load active power of each of the plurality of consumers 21A, 23A based on the difference Pa-Pae. The formula for updating is
PLi = PLi + βPLi · (Pa−Pae) (αPLi / αPL2)
(I = 1, 3). Here, βPLi is a convergence coefficient as already described in FIG. 1, and is a constant greater than 0 and less than or equal to 1. As the convergence coefficient βPLi, a coefficient held in advance in the convergence coefficient storage holding unit 59B is used.

  Next, the operation in the calculation setting unit 61A is as already described. That is, the set load reactive power QLi for each consumer is calculated using the set load reactive power PLi and a predetermined power factor (for example, 0.95). The subsequent operation is different from the above description, and passes through the calculation setting unit 63 and the temporary setting unit 65A. This path is controlled by the control unit 71. This is because, in the second and subsequent operations of the calculation setting unit 61A, even if the calculation setting unit 63 is operated, the operation result only yields the same result, and the setting power supply active power PLpvi is temporarily set as this device. This is because it was decided not to change after setting.

  The calculation setting unit 61A estimates and calculates the new set load power (set load active power PL1 to PL3 and set load reactive power QL1 to QL3) and set power supply active power PLpv1 and PLpv3 for each of the consumers 21A, 22, and 23A. Send to part 55B. And the operation | movement in the estimation calculation part 55B or less is as having already demonstrated. In other words, the operation of the loop formed by the cascade of the resetting update unit 53B, the calculation setting unit 61A, the estimation calculation unit 55B, and the difference evaluation determination unit 57 is | Pa−Pae | ≦ εp and | When it is determined that Qa−Qae | ≦ εq, the estimated ultimate voltage VL1e and VL3e that are considered to be accurately estimated are held in the estimated ultimate voltage storage holding unit 58 at that time.

  As described above, according to this embodiment, the information about the representative customer 22 is utilized, and the voltage reached to the consumers 21A and 23A without a measuring instrument is distributed between these consumers 21A and 23A. Under the premise that the power supply is provided, it is possible to estimate the estimated arrival voltages VL1e and VL3e with high accuracy. Note that the operation of the apparatus shown in FIG. 6 can be easily expressed as a flowchart according to FIG.

(Embodiment 4)
Next, the ultimate voltage estimation apparatus of Embodiment 4 is demonstrated with reference to FIG. FIG. 8 shows the configuration of the ultimate voltage estimating apparatus according to the fourth embodiment together with the estimation object. In the figure, the same components as those shown in the already described drawings are denoted by the same reference numerals, and description thereof will be omitted unless there is a point to be added. This embodiment is an apparatus obtained by slightly modifying the one shown in FIG. In this sense, this apparatus assumes a case where a plurality of consumers 21A and 23A each have a distributed power source, and in particular, the reactive power component Qa of the power flow in the measuring instrument 1b is very close to zero. It is the same as that shown in FIG.

  As shown in FIG. 8, this ultimate voltage estimation device is different from any of the functional blocks shown in FIGS. 4 and 6, as shown in FIG. 8. It has a temporary setting unit / re-setting / updating unit 65B for the power source active power. Hereinafter, for the convenience of explanation, these functional blocks may be abbreviated as a temporary setting unit 53C and a temporary setting unit 65B (in some cases, a resetting update unit 65B).

  This embodiment will be described from the point of difference from the embodiment shown in FIG. In this embodiment, first, the acquisition unit 51A, the calculation unit 52, the temporary setting unit 53C, the calculation setting unit 61A, the calculation setting unit 63, the temporary setting unit 65B, the estimation calculation unit 55B, and the difference evaluation determination unit 57 are performed in this order. The first operation is exactly the same as that of the embodiment shown in FIG. That is, the temporary setting unit 53B in FIG. 6 is changed in sign to the temporary setting unit 53C in FIG. 8, but performs the same operation here. The temporary setting unit 65A in FIG. 6 is changed in sign to the temporary setting unit 65B in FIG. 8, but performs the same operation here.

  Then, if it cannot be said that | Pa−Pae | ≦ εp and | Qa−Qae | ≦ εq, the difference evaluation determination unit 57 performs virtual distribution of the set power source effective power for each of the consumers 21A and 23A. In order to start over, this is notified to the resetting update unit 65B. This point is different from the embodiment shown in FIG. At that time, the numerical values of the differences Pa-Pae and Qa-Qae are also transmitted. The reset update unit 65B is informed of the load active power PL of the representative customer 22 first, and based on this, the set load active power is temporarily transmitted to the other consumers 21A and 23A. This is because it is assumed that the setting has a high accuracy reflecting the reality. In such a case, it is considered that it is possible to achieve convergence with high estimation accuracy by re-performing virtual distribution of the set power source active power for each of the consumers 21A and 23A.

The resetting update unit 65B adjusts, resets, and updates the set load active power of each of the plurality of consumers 21A and 23A based on the difference Pa-Pae. The formula for updating is
PLpvi = PLpvi + βPLpvi · (Pa−Pae) (αPLpvi / ΣαPLpvi)
(I = 1, 3; from the point already described, PLpv2 is 0). Here, βPLpvi is a convergence coefficient as already described with reference to FIG. 4, and is a constant greater than 0 and equal to or less than 1. As the convergence coefficient βPLpvi, a coefficient held in advance in the convergence coefficient storage holding unit 66 is used.

  Then, the resetting update unit 65B sets the set load power (set load active power PL1 to PL3 and set load reactive power QL1 to QL3) for each of the consumers 21A, 22, and 23A, and the new set power source active powers PLpv1 and PLpv3. Is sent to the estimation calculation unit 55B. And the operation | movement in the estimation calculation part 55B or less is as having already demonstrated. In other words, the operation of the loop formed by the cascade of the resetting update unit 65B, the estimation calculation unit 55B, and the difference evaluation determination unit 57 is | Pa−Pae | ≦ εp and | Qa−Qae | ≦ in the difference evaluation determination unit 57. The process ends when it is determined that εq, and the estimated reaching voltage VL1e and VL3e that are considered to be accurately estimated are held in the estimated reaching voltage storage holding unit 58 at that time.

  As described above, according to this embodiment, as in the apparatus shown in FIG. 6, the information about the representative customer 22 is utilized, and the voltage reached to the consumers 21A and 23A without the measuring instrument is Under the premise that these consumers 21A and 23A have distributed power sources, the estimated arrival voltages VL1e and VL3e can be estimated with high accuracy. In particular, when the load effective power PL of a representative customer 22 is grasped, and the provisional setting of the set load active power for the other customers 21A and 23A based on this is a setting with high accuracy reflecting the reality. Is suitable. It should be noted that the operation of the apparatus shown in FIG. 8 can be easily expressed as a flowchart according to FIG.

(Embodiment 5)
Next, the ultimate voltage estimation apparatus of Embodiment 5 is demonstrated with reference to FIG. FIG. 9 shows the configuration of the ultimate voltage estimation device of Embodiment 5 together with the estimation object. In the figure, the same components as those shown in the already described drawings are denoted by the same reference numerals, and description thereof will be omitted unless there is a point to be added. This embodiment also assumes the case where each of the plurality of consumers 21A and 23A has a distributed power source, and in particular, the reactive power component Qa in the power flow in the measuring instrument 1b is very close to zero. It is a device that can handle cases.

  The major difference between this embodiment and the apparatus shown in FIGS. 6 and 8 is that the difference evaluation determination unit 57A determines whether or not | Pa−Pae | ≦ εp and | Qa−Qae | ≦ εq. This is in the point where the judgment regarding the active power and the judgment regarding the reactive power are separated. Since the separation is performed in this way, there is a slight change in the difference evaluation determination unit 57A and each functional block that performs the operation leading to the difference evaluation determination unit 57A. The determination is separated in this way in the operation of performing the setting setting of the set load reactive power for each consumer as a result of the temporary setting of the set load active power or the resetting update, in the power factor storage holding unit 62A. This is because it is inconvenient when the held power factor is not accurate. If this power factor does not reflect the actual condition and is not accurate, there is a possibility that the result of | Qa−Qae | ≦ εq will not converge so that it becomes true.

  Therefore, in this embodiment, as a summary, the set load active power for each consumer is distributed so that the determination result of | Pa−Pae | ≦ εp becomes true first, and | Qa−Qae using the result. The set load reactive power for each consumer is distributed so that the determination result of | ≦ εq becomes true.

  As shown in FIG. 9, this ultimate voltage estimation device is different from any of the functional blocks in the diagram already described, and includes a calculation setting unit / resetting / updating unit 61B for setting load reactive power for each consumer, a convergence coefficient, 59 C of memory | storage holding | maintenance units, the difference evaluation judgment part 57A of the measured value and estimated value of an upstream tidal current, the setting load active power memory | storage holding | maintenance part 67, and the control parts 72, 73, and 74 are provided. In the following, for the convenience of explanation, these functional blocks excluding the control unit are referred to as a calculation setting unit 61B (reset update unit 61B in some cases), a storage holding unit 59C, a difference evaluation determination unit 57A, and a storage holding unit 67. May be abbreviated. Although overlapping with what has already been described, the assumed estimation object in this ultimate voltage estimation device is the same as that shown in FIG.

  This embodiment will be described below in terms of the difference from the embodiment shown in FIG. 6 (or FIG. 8). In this embodiment, first, regarding the first operation performed in the order of the capturing unit 51A, the calculation unit 52, the temporary setting unit 53B, the calculation setting unit 61B, the calculation setting unit 63, the temporary setting unit 65A, and the estimation calculation unit 55B, This is exactly the same as the embodiment shown in FIG. That is, the calculation setting unit 61B in FIG. 6 is changed in sign to the calculation setting unit 61B in FIG. 9, but performs the same operation here.

  Next, the difference evaluation determination unit 57A determines whether or not | Pa−Pae | ≦ εp. If this result is not true, the virtual load of the set load active power for each of the consumers 21A and 23A is determined. In order to redo appropriate distribution, this is notified to the resetting update unit 53B. This operation in the difference evaluation determination unit 57A is one difference from the embodiment shown in FIG. At that time, the numerical values of the differences Pa-Pae and Qa-Qae are also transmitted. The control of the control unit 74 is involved in the operation transition from the difference evaluation determination unit 57A to the resetting update unit 53B.

  Next, an operation is performed in the order of the resetting update unit 53B and the estimation calculation unit 55B. The control unit 72 is interposed in the control of the operation transition from the resetting update unit 53B to the estimation calculation unit 55B. This series of operations of the resetting update unit 53B and the estimation calculation unit 55B can be understood with reference to the description in FIG. The subsequent operation in the difference evaluation determination unit 57A is a determination as to whether or not | Pa−Pae | ≦ εp as described above. As a result, the operation of the loop formed by cascading the resetting update unit 53B, the estimation calculation unit 55B, and the difference evaluation determination unit 57A is determined by the difference evaluation determination unit 57A as | Pa−Pae | ≦ εp. End at the moment. Then, the difference evaluation determination unit 57A records the set load active power PLi at that time in the set load power storage holding unit 67.

  After the difference evaluation determination unit 57A records the set load active power PLi in the storage holding unit 67, the difference evaluation determination unit 57A determines whether or not | Qa−Qae | ≦ εq at this time. This operation transition of the difference evaluation determination unit 57A is controlled by the control unit 74. Here, a case where the determination result in the difference evaluation determination unit 57A is | Qa−Qae | ≦ εq will be described later.

  On the other hand, if it cannot be said that | Qa−Qae | ≦ εq, the difference evaluation determination unit 57A redistributes the set load reactive power for each of the consumers 21A and 23A. Tell. At that time, the numerical values of the differences Pa-Pae and Qa-Qae are also transmitted. Control of the control unit 74 is involved in the operation transition from the difference evaluation determining unit 57A to the resetting and updating unit 61B. The calculation setting unit 61B at this time uses the value held in the memory holding unit 67 for the set load active power. Operations subsequent to the calculation setting unit 61B are in the order of the estimation calculation unit 55B and the difference evaluation determination unit 57A. A control unit 73 is interposed in the control of the operation transition from the calculation setting unit 61B to the estimation calculation unit 55B. The difference evaluation determination unit 57A determines whether or not | Qa−Qae | ≦ εq. Here, the case where the determination result in the difference evaluation determination unit 57A is successfully | Qa−Qae | ≦ εq will be described later.

  On the other hand, if the judgment in the difference evaluation judgment unit 57A cannot be said to be | Qa−Qae | ≦ εq, the setting load reactive power is redistributed for each of the consumers 21A and 23A. Tell part 61B. At that time, the numerical values of the differences Pa-Pae and Qa-Qae are also transmitted. Control of the control unit 74 is involved in the operation transition from the difference evaluation determining unit 57A to the resetting and updating unit 61B.

The resetting update unit 61B adjusts, resets, and updates the set load reactive power of each of the plurality of consumers 21A, 23A based on the difference Qa-Qae. The formula for updating is
QLi = QLi + βQLi · (Qa−Qae) (αQLi / αQL2)
(I = 1, 3). Here, βQLi is a convergence coefficient and is a constant greater than 0 and equal to or less than 1. As the convergence coefficient βQLi, a coefficient held in advance in the convergence coefficient storage holding unit 59C is used.

  The operation following the resetting update unit 61B is in the order of the estimation calculation unit 55B and the difference evaluation determination unit 57A. These operations are as described above. In other words, the operation of the loop formed by the cascade of the resetting update unit 61B, the estimation calculation unit 55B, and the difference evaluation determination unit 57A is determined by the difference evaluation determination unit 57A to be | Qa−Qae | ≦ εq. End at the moment.

  The subsequent operation in the case where the determination in the difference evaluation determination unit 57A, which is postponed in the above description, is | Qa−Qae | ≦ εq will be described below. In this case, the difference evaluation determination unit 57A determines whether or not | Pa−Pae | ≦ εp + at this time. This operation transition of the difference evaluation determination unit 57A is controlled by the control unit 74. Here, the threshold εp + is an appropriate value larger than εp. If this result is true, it is determined that the estimated reached voltages VL1e and VL3e at that time are accurately estimated voltages, and the difference evaluation judging unit 57A stores the values in the estimated reached voltage storage holding unit 58. Record.

  On the other hand, if it cannot be said that | Pa−Pae | ≦ εp +, the difference evaluation determination unit 57A determines whether or not | Pa−Pae | ≦ εp at this time. This operation transition of the difference evaluation determination unit 57A is controlled by the control unit 74. The result of this determination is always false (because εp <εp +), and therefore the operation shifts from the difference evaluation determination unit 57A to the resetting update unit 53B, and the subsequent operation is performed. This operation transition of the difference evaluation determination unit 57A is controlled by the control unit 74. Subsequent operations in this case are the same as those already described.

  As a result of the above operation, when the determination by the difference evaluation determination unit 57A is | Qa−Qae | ≦ εq + as a whole, the operation is completed as a whole, and the estimated ultimate voltages VL1e and VL3e at that time are accurately estimated. Therefore, it is recorded in the estimated ultimate voltage storage unit 58.

  According to this embodiment, similarly to the apparatus shown in FIG. 6, the information about the representative customer 22 is utilized, and the voltage reached to the consumers 21A, 23A without a measuring instrument is changed to these consumers 21A, Under the assumption that 23A has a distributed power source, the estimated ultimate voltages VL1e and VL3e can be accurately detected even if the power factor held in the power factor memory holding unit 62A is not accurate. It can be estimated high.

  Note that, in this embodiment, | Pa−Pae | and | Qa−Qae | are determined in series in this embodiment, so that one is converged and the other is not converged. There is no possibility of repetition. Such a case can be dealt with by appropriately changing the thresholds εp, εq, and εp + for the determination.

  Incidentally, when the operation of the ultimate voltage estimating apparatus of the fifth embodiment described above is shown as a flowchart, it becomes as shown in FIG. In FIG. 10, when 100 is subtracted from the code of each step, it corresponds to each functional block shown in FIG. In the case where two or more steps correspond to each functional block in FIG. 9, suffixes a, b,... Are added to the reference numerals in the steps in FIG. FIG. 10 can be easily understood from the contents described above with reference to FIG.

(Embodiment 6)
Next, the ultimate voltage estimation apparatus of Embodiment 6 is demonstrated with reference to FIG. FIG. 11 shows the configuration of the ultimate voltage estimation apparatus according to the sixth embodiment together with the estimation object. In the figure, the same components as those shown in the already described drawings are denoted by the same reference numerals, and description thereof will be omitted unless there is a point to be added. In this embodiment, the apparatus shown in FIG. 9 is slightly modified.

  The difference of this embodiment from the above-described embodiment 5 is that in the convergence loop operation of | Pa-Pae |, instead of resetting and updating the set load active power for each consumer, the set power source for each consumer This is the point that the active power is reset and updated. For this reason, the functional block diagram shown in FIG. 11 is changed to correspond to this point from that of FIG.

  Regarding the reason and advantage of such a change, the point described as the difference between the fourth embodiment and the third embodiment can be referred to. If it repeats, the load effective electric power PL of the typical consumer 22 will be grasped first, and based on this, the setting load effective electric power was temporarily set with respect to the other consumers 21A and 23A, reflecting the reality. This is because it is assumed that the setting is highly accurate. In such a case, it is considered that it is possible to achieve convergence with high estimation accuracy if the virtual distribution of the set power source active power for each of the consumers 21A and 23A is redone.

  The change for the above will be described with reference to FIG. 9. In FIG. 9, the convergence loop operation of | Pa−Pae | is an operation by the loop of the resetting update unit 53B, the estimation calculation unit 55B, and the difference evaluation determination unit 57A. However, in FIG. 11, the convergence loop operation of | Pa−Pae | is an operation by a loop of the resetting update unit 65B, the estimation calculation unit 55B, and the difference evaluation determination unit 57A. In FIG. 11, since the set load active power is not re-set and updated as a result of this loop operation, the set load active power storage holding unit 67 in FIG. 9 becomes unnecessary.

  Further, the resetting update unit 65B in FIG. 11 is a function added to the temporary setting unit 65A in FIG. 9, but a convergence coefficient storage holding unit 66 is provided to perform the added resetting update. The memory holding unit 66 has already been shown in FIG. 9 and the description thereof has already been described. A convergence coefficient storage holding unit 59D in FIG. 11 is the same as the convergence coefficient storage holding unit 59C shown in FIG. 9 as a function for the resetting update unit 61B. The storage holding unit 59C is different from the storage holding unit 59D shown in FIG. 11 in that it provides a convergence coefficient also to the resetting update unit 53B, so the sign is changed.

(Embodiment 7)
Next, the ultimate voltage estimation apparatus of Embodiment 7 is demonstrated with reference to FIG. FIG. 12 shows the configuration of the ultimate voltage estimating apparatus according to the seventh embodiment together with the estimation object. In the figure, the same components as those shown in the already described drawings are denoted by the same reference numerals, and description thereof will be omitted unless there is a point to be added. The seventh embodiment is also an apparatus in which the one shown in FIG. 9 is slightly modified (a different modification from the apparatus shown in FIG. 11), similarly to the one shown in FIG.

  The difference of this embodiment from the above-described embodiment 5 is that in the convergence loop operation of | Qa−Qae |, instead of resetting the set load reactive power based on the difference Qa−Qae and the convergence coefficient βQLi, The power factor for calculating the set load reactive power from the set load active power is adjusted based on the sign of the difference Qa-Qae to recalculate the set load reactive power and reset it. Such a change can be appropriately selected and adopted by comparing the performance with the convergence loop operation of | Qa−Qae | in the fifth embodiment. The functional block diagram of FIG. 12 is changed to correspond to this point from that of FIG.

To explain the change for the above, in FIG. 11, the power factor storage holding unit 62A in FIG. 9 is added as a power factor / adjustment power factor storage holding unit 62B. Then, the resetting update unit 61C adjusts, resets, and updates the set load reactive power of each of the plurality of consumers 21A, 23A as follows. The formula for updating is
QLi = (PLi / adjustment power factor) √ (1−adjustment power factor ² )
(I = 1, 3). Here, the adjustment power factor is supplied from the memory holding unit 62B. The adjustment power factor is, for example, a value obtained by adding 0.0001 to the original power factor when the sign of the difference Qa-Qae is positive, and is 0 from the original power factor when the sign of the difference Qa-Qae is negative. It can be determined to be a value obtained by subtracting .0001.

  The point adopted in this embodiment as a difference from the fifth embodiment (FIG. 9) can be adopted as appropriate in the sixth embodiment (FIG. 11).

(Embodiment 8)
Next, the ultimate voltage estimation apparatus of Embodiment 8 is demonstrated with reference to FIG. As shown in the figure, this ultimate voltage estimation apparatus includes an information storage unit 90, a determination unit 91, a control unit 92, a determination unit 93, a control unit 94, a determination unit 95, a control unit 96, and a control unit 97. Although not shown, this apparatus is shown in any of the apparatus shown in FIG. 1, the apparatus shown in FIG. 4, the apparatus shown in FIG. 6 or 8, and any of FIG. 9, FIG. 11, and FIG. It is assumed that the device is configured to function at least as a total of four types of devices.

  As already explained, each of the above four types of devices has its characteristics. Therefore, in this embodiment, in order to make better use of these depending on the situation, a function is added and functions are integrated so as to operate as each device according to the situation.

  The determination unit 91 determines from the information stored in the information storage unit 90 as a first determination whether or not the distributed power source is functioning in at least one of the plurality of consumers at the present time. When the result of the first determination is false, the control unit 92 controls the device to function as the device shown in FIG. When the result of the first determination is true, the determination unit 93 determines from the information in the information storage unit 90 whether or not the upstream power flow has reactive power at this time as the second determination.

  And the control part 94 is controlled to function as an apparatus shown in FIG. 4, when the result of a 2nd judgment is true. When the result of the second determination is false, the determination unit 95 determines from the information in the information storage unit 90 whether or not the power factor held by the power factor storage holding unit 62A at present is a highly reliable value. Judgment is performed as a third judgment. When the result of the third determination is true, the control unit 97 controls to function as the device shown in FIG. 6 or FIG. When the result of the third determination is false, the control unit 97 performs control so as to function as the device illustrated in any of FIGS. 9, 11, and 12.

  It can be easily understood that the functions of the determination units 91, 93, 95 and the control units 92, 94, 96, 97 are reasonable from the points described in the description of the embodiments. Conceivable.

  The information storage unit 90 stores information that can contribute to the determination in the determination units 91, 93, and 95. This information shall be updated from time to time to reflect the actual situation. To update to reflect the actual situation, it can be configured to search for various information periodically (on a regular basis) and automatically retain the results, or manually enter information about the actual situation as appropriate. You may apply that. The timing at which the determination units 91, 93, 95 and the control units 92, 94, 96, 97 shown in FIG. 13 are operated can be, for example, every hour. If it is 1 hour, the mode can be changed as a device up to 24 times a day.

  As described above, according to each embodiment, it is possible to estimate a voltage reached to a consumer without a measuring instrument in accordance with the situation. The comprehensive principle is as follows. The first voltage, current, and power factor are taken from the first measuring instrument upstream of the plurality of consumers, and the second voltage, current, and power factor are obtained from the second measuring instrument provided on the downstream side. The first current based on the first voltage, current, and power factor, the second current based on the second voltage, current, and power factor, and the second current based on the first and second currents. The total load power between the first and second measuring instruments is calculated.

  Then, the total load power is virtually allocated, and is initially set as the set load power for each of the plurality of consumers. The line information between the first and second measuring instruments, the set load power, the first Using the voltage and the second tidal current, the third tidal current estimated by the first measuring instrument and the estimated ultimate voltage at each of the plurality of consumers are calculated, and the difference between the first tidal current and the third tidal current Is not within the threshold value, and if not, the set load power is updated and set to recalculate the estimated third power flow and the estimated reached voltage.

  When the difference between the first tidal current and the third tidal current falls within the threshold, it is determined that the estimated reached voltage at that time is the accurately estimated voltage. In other words, the upstream load flow is calculated using the set load power virtually set for the customer, and the load flow calculation result is not significantly different from the actual measurement value. This is because the distribution of the set load power for each is considered not to be significantly different from the actual.

  Each of the above embodiments has been described as an apparatus, but a program that causes a general-purpose computer to function as described in each of the above apparatuses can be easily realized. That is, the embodiment of the program can be easily realized.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  1, 2 ... Branch area, 1a, 2a ... Transmission line, 1b ... Measuring instrument (upstream side), 1c ... Measuring instrument (downstream side), 1d ... Transmission line, 1e ... Distribution system bus, 11 ... Power supply, 12 ... Core system bus, 13 ... branch system transformer, 14 ... branch system bus, 15 ... dedicated communication line, 21,22,23 ... customer, 21A, 22A, 23A ... customer (with distributed power supply), 31 ... measurement 51, 51A ... measurement result capturing unit, 52 ... upstream tidal current / downstream tidal current / total load power calculation unit, 53 ... set load power initial setting unit / reset update unit, 53A ... Initial setting unit / resetting update unit for set load reactive power, 53B ... Temporary setting unit / resetting update unit for set load active power, 53C ... Temporary setting unit for set load active power, 54 ... Initial setting coefficient storage holding unit, 54A ... Temporary setting coefficient memory holding unit, 55, 55A, 55B Upstream power flow / arrival voltage estimation calculation unit, 56 ... line information storage holding unit, 57, 57A ... difference evaluation determination unit, 58 ... estimated arrival voltage storage holding unit, 59, 59A, 59B, 59C, 59D ... convergence coefficient storage Holding unit 61... Setting load active power calculation setting unit 61 A. Setting load reactive power calculation setting unit 61 B, 61 C. Setting load reactive power calculation setting unit / resetting update unit 62 62 A... Power factor storage Holding unit, 62B: Power factor / adjustment power factor storage holding unit, 63: Calculation setting unit for total power of distributed power source, 64: Initial setting coefficient storage holding unit, 64A: Temporary setting coefficient storage holding unit, 65: Setting power source Initial setting unit / reset update unit for active power, 65A ... Temporary setting unit for set power source active power, 65B ... Temporary setting unit / reset update unit for set power source active power, 66 ... Convergence coefficient storage holding unit, 67 ... Setting Load active power storage , 71, 72, 73, 74 ... control unit, 90 ... information storage unit, 91 ... judgment unit, 92 ... control unit, 93 ... judgment unit, 94 ... control unit, 95 ... judgment unit, 96 ... control unit, 97 ... control unit.

Claims (9)

A first value that is the value of the voltage from a first measuring instrument that measures the voltage, current, and power factor provided on the upstream side of the transmission line connected to the plurality of consumers as viewed from the plurality of consumers. Means for capturing a voltage of the first current, a first current that is the value of the current, and a first power factor that is the value of the power factor;
A second voltage, which is a value of the voltage, from the second measuring instrument that measures the voltage, current, and power factor provided on the downstream side of the power transmission line as viewed from the plurality of consumers. Means for taking in a second current that is a value of and a second power factor that is the value of the power factor;
Based on the first voltage, the first current, and the first power factor, a first tidal current that is a tidal current at the first measuring instrument of the transmission line is changed to the second voltage, Based on the second current and the second power factor, a second tidal current that is a tidal current at the second measuring instrument of the transmission line is further changed to the first tidal current and the second tidal current. And a means for calculating a total load power consumed between the first measuring instrument and the second measuring instrument, respectively,
Means for virtually allocating the total load power and initially setting the set load power for each of the plurality of consumers;
Using line information between the first measuring instrument and the second measuring instrument of the transmission line, the set load power of each of the plurality of consumers, the first voltage, and the second tidal current Means for calculating a third tidal current that is an estimated tidal current in the first measuring instrument and an estimated ultimate voltage that is an estimated ultimate voltage in each of the plurality of consumers;
Means for determining whether or not a difference between the first tide and the third tide is within a preset threshold;
And a means for adjusting, resetting, and updating the set load power of each of the plurality of consumers based on the difference when the difference does not fall within the threshold. Means for virtually distributing the total load reactive power that is the reactive portion of the total load power, and initially setting the set load reactive power for each of the plurality of consumers;
Means for calculating and setting the load active power corresponding to the set load reactive power in each of the plurality of consumers as the set load active power based on the set load reactive power and a third power factor given in advance. When,
By subtracting the sum of the plurality of consumers of the set load active power from the total load active power that is an effective component of the total load power, the first measuring instrument and the second measuring instrument Means for calculating and setting the total power output by the distributed power source existing between them as the total power source active power;
Means for virtually allocating the total power source active power according to a rated output of a distributed power source possessed by each of the plurality of consumers, and initially setting the set power source active power for each of the plurality of consumers; ,
Using the line information, the set load reactive power of each of the plurality of consumers, the set load active power, and the set power source active power, the first voltage, and the second power flow, Means for calculating a fourth tidal current that is an estimated tidal current at the measuring instrument and a second estimated ultimate voltage that is an estimated ultimate voltage at each of the plurality of consumers;
Means for determining whether or not a second difference that is a difference between the first tidal current and the fourth tidal current is within a second threshold that is a predetermined threshold;
Means for adjusting, resetting, and updating the set load reactive power of each of the plurality of consumers based on the second difference when the second difference is not within the second threshold. When,
Means for adjusting, resetting and updating the set power source active power of each of the plurality of consumers based on the second difference when the second difference is not within the second threshold The ultimate voltage estimation apparatus according to claim 1, further comprising: Means for capturing information on representative load active power that is load active power consumed by one representative customer among the plurality of consumers;
The total load active power is virtually distributed based on the representative load active power and the interrelationship of the past load active power in the plurality of consumers, and the plurality of consumers excluding the representative consumer Means for provisionally setting each second set load active power;
In each of the plurality of consumers, the representative load active power or the second set load active power corresponding to the representative load active power or the second set load active power is given in advance. Means for calculating and setting the second set load reactive power based on the fourth power factor;
A distributed power source existing between the first measuring instrument and the second measuring instrument by subtracting the sum of the plurality of consumers of the second set load active power from the total load active power Means for calculating and setting the total power output by the second total power source active power;
The second total power source active power is virtually distributed according to the rated output of the distributed power source possessed by each of the plurality of consumers, and each of the plurality of consumers excluding the representative consumer. Means for temporarily setting as the set power source active power of 2;
The line information, the representative load active power, the second set load reactive power of the representative consumer, the second set load active power of each of the plurality of consumers excluding the representative consumer, the second A fifth tidal current that is an estimated power flow in the first measuring instrument using a set load reactive power, the second set power source active power, the first voltage, and the second power flow, Means for performing a power flow calculation so as to calculate at least a third estimated ultimate voltage that is an estimated ultimate voltage in each of the plurality of consumers excluding the representative consumer;
Means for determining whether or not a third difference that is a difference between the first tide and the fifth tide is within a predetermined third threshold;
When the third difference does not fall within the third threshold, the second set load active power of each of the plurality of consumers excluding the representative consumer is calculated based on the third difference. The reached voltage estimating device according to claim 2, further comprising means for adjusting and resetting.   When the third difference does not fall within the third threshold, based on the third difference, the second set power source active power for each of the plurality of consumers excluding the representative consumer 4. The ultimate voltage estimating apparatus according to claim 3, further comprising means for adjusting and resetting. It is determined whether or not a fourth difference that is a difference between an active power component of the first power flow and an active power component of the fifth power flow is within a predetermined fourth threshold. Means to
When the fourth difference is not within the fourth threshold, based on the fourth difference, the second set load active power of each of the plurality of consumers excluding the representative consumer is calculated. Means to adjust and re-set,
Control is performed so as to provide the second set load reactive power to the power flow calculation without changing the second set load reactive power even when the second set load active power is reset. Means,
It is determined whether or not a fifth difference that is a difference between the reactive power component of the first power flow and the reactive power component of the fifth power flow is within a predetermined fifth threshold. Means to
When the fifth difference does not fall within the fifth threshold, based on the fifth difference, the second set load reactive power of each of the plurality of consumers excluding the representative consumer Means to adjust and re-set,
The fourth difference obtained when determining whether the fifth difference is within the fifth threshold is within a predetermined sixth threshold that is greater than the fourth threshold. A means of determining whether or not
When the fourth difference obtained at the time of determination does not fall within the sixth threshold, the second set load reactive power obtained at the time of determination for the power flow calculation The ultimate voltage estimating apparatus according to claim 3, further comprising: a control unit configured to provide the following. It is determined whether or not a fourth difference that is a difference between an active power component of the first power flow and an active power component of the fifth power flow is within a predetermined fourth threshold. Means to
When the fourth difference is not within the fourth threshold, the second set power source active power of each of the plurality of consumers excluding the representative consumer is calculated based on the fourth difference. Means to adjust and re-set,
It is determined whether or not a fifth difference that is a difference between the reactive power component of the first power flow and the reactive power component of the fifth power flow is within a predetermined fifth threshold. Means to
When the fifth difference does not fall within the fifth threshold, based on the fifth difference, the second set load reactive power of each of the plurality of consumers excluding the representative consumer Means to adjust and re-set,
The fourth difference obtained when determining whether the fifth difference is within the fifth threshold is within a predetermined sixth threshold that is greater than the fourth threshold. A means of determining whether or not
When the fourth difference obtained at the time of determination does not fall within the sixth threshold, the second set load reactive power obtained at the time of determination for the power flow calculation The ultimate voltage estimating apparatus according to claim 3, further comprising: a control unit configured to provide the following. It is determined whether or not a fourth difference that is a difference between an active power component of the first power flow and an active power component of the fifth power flow is within a predetermined fourth threshold. Means to
When the fourth difference is not within the fourth threshold, based on the fourth difference, the second set load active power of each of the plurality of consumers excluding the representative consumer is calculated. Means to adjust and re-set,
Control is performed so as to provide the second set load reactive power to the power flow calculation without changing the second set load reactive power even when the second set load active power is reset. Means,
It is determined whether or not a fifth difference that is a difference between the reactive power component of the first power flow and the reactive power component of the fifth power flow is within a predetermined fifth threshold. Means to
When the fifth difference is not within the fifth threshold, the representative load active power or the second set load active power, and the power factor after the fourth power factor is adjusted Based on a fifth power factor, means for adjusting and resetting the second set load reactive power of each of the plurality of consumers excluding the representative consumer;
The fourth difference obtained when determining whether the fifth difference is within the fifth threshold is within a predetermined sixth threshold that is greater than the fourth threshold. A means of determining whether or not
When the fourth difference obtained at the time of determination does not fall within the sixth threshold, the second set load reactive power obtained at the time of determination for the power flow calculation The ultimate voltage estimating apparatus according to claim 3, further comprising: a control unit configured to provide the following. Means for determining, as a first determination, whether or not a distributed power source is functioning in at least one of the plurality of consumers at the present time from the first information that is given information;
Means for controlling to function as the apparatus of claim 1 when the result of the first determination is false;
When the result of the first determination is true, a determination as to whether or not the first power flow currently has reactive power is performed as a second determination from the second information that is given information. Means,
Means for controlling to function as an apparatus according to claim 2 when the result of said second determination is true;
When the result of the second determination is false, a determination as to whether or not the fourth power factor is a highly reliable value at the present time from the third information that is the given information is a third determination. Means to do,
The ultimate voltage estimating apparatus according to claim 5, further comprising: a unit configured to control the apparatus to function as the apparatus according to claim 3 when the result of the third determination is true. A first value that is the value of the voltage from a first measuring instrument that measures the voltage, current, and power factor provided on the upstream side of the transmission line connected to the plurality of consumers as viewed from the plurality of consumers. Means for capturing a voltage of the first current, a first current that is the value of the current and a first power factor that is the value of the power factor
A second voltage, which is a value of the voltage, from the second measuring instrument that measures the voltage, current, and power factor provided on the downstream side of the power transmission line as viewed from the plurality of consumers. Means for capturing a second current that is a value of the second power factor, and a second power factor that is the value of the power factor;
Based on the first voltage, the first current, and the first power factor, a first tidal current that is a tidal current at the first measuring instrument of the transmission line is changed to the second voltage, Based on the second current and the second power factor, a second tidal current that is a tidal current at the second measuring instrument of the transmission line is further changed to the first tidal current and the second tidal current. A means for calculating a total load power consumed between the first measuring instrument and the second measuring instrument, respectively,
Means for virtually allocating the total load power and initially setting the set load power for each of the plurality of consumers;
Using line information between the first measuring instrument and the second measuring instrument of the transmission line, the set load power of each of the plurality of consumers, the first voltage, and the second tidal current Means for calculating a third tidal current that is an estimated tidal current in the first measuring instrument and an estimated ultimate voltage that is an estimated ultimate voltage in each of the plurality of consumers;
Means for determining whether or not a difference between the first tidal current and the third tidal current is within a preset threshold; and when the difference is not within the threshold, based on the difference A program for estimating an arrival voltage that causes a computer to function as means for adjusting, resetting, and updating the set load power of each of the plurality of consumers.

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