JP4117201B2 - Distribution line breakage detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disconnection detecting device for detecting disconnection of a distribution line.
[0002]
[Prior art]
Distribution lines may be disconnected due to unforeseen causes, regardless of aerial wiring or underground wiring. In this case, in order to recover quickly, it is necessary to find the disconnected position as soon as possible. However, since the distribution line is generally very long, its detection is not easy. In a conventional disconnection detection device, disconnection in one distribution line section is detected from current and voltage values measured at a plurality of points on the distribution line. (For example, see Patent Document 1)
And the true disconnection point of the distribution line where the disconnection is detected, for example, it takes a long time because it is necessary for a person to move and discover along the distribution line, causing a delay in recovery. .
[0003]
In addition, when a distributed power source is present at the terminal end of the distribution line, the terminal voltage may not change significantly even if the distribution line in the middle is disconnected, and the failure section may not be determined. In addition, since the neutral point of the high-voltage distribution line is normally ungrounded, it is out of consideration to determine the failure section for the distribution line with ground impedance.
[0004]
[Patent Document 1]
JP-A-2-266822 (page 8, FIG. 1)
[0005]
[Problems to be solved by the invention]
Since the conventional disconnection detection apparatus is configured as described above, there is a problem that even if a disconnection section can be automatically detected by this apparatus, a disconnection point cannot be detected. In addition, when a distributed power source exists on the terminal side of the distribution line, the failure section may not be able to be standardized even if the distribution line in the middle is disconnected. In addition, since the neutral point of the high-voltage distribution line is normally ungrounded, there is a problem that no consideration is given to locating a failure section for a distribution line having a ground impedance.
[0006]
The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a disconnection detection device capable of locating not only a failure section but also a failure point. It is another object of the present invention to provide a device that can locate a failure section and a failure point by unified handling even when a distributed power source is present at the end of a distribution line. Further, it is an object of the present invention to obtain a device capable of locating a failure section and a failure point by uniform handling even for a distribution line having a ground impedance that is normally ungrounded in a high-voltage distribution line.
[0007]
[Means for Solving the Problems]
  The distribution line disconnection detecting device according to the present invention is arranged at a measurement point set in each of the sections of the distribution line divided into a plurality of sections, and detects the voltage and current of the distribution line at the measurement points. Sensors that calculate normal-phase, reverse-phase, and zero-phase voltages and currents and convert them to data, and transmit this data to the outside via communication lines.
  The data is received from each sensor of the plurality of sections via the communication line, and the sum of the positive phase current value, the negative phase current value, and the zero phase current value of the distribution line is calculated, and the positive phase current When the value is not zero and the sum of the positive phase current value, the negative phase current value, and the zero phase current value is zero, a disconnection detection signal is output to indicate that there is one disconnection in the distribution line.And
Difference in positive phase voltage between the measurement points at both ends of each sectionOr any one of the difference of the negative phase voltage or the difference of the zero phase voltageCalculate for all the sections, determine that there is a disconnection of the one line in the section where this difference is the largest, and output a disconnection section signalDoSection judgmentEquipment, and
SaidBased on the positive phase voltage and the negative phase voltage at each measurement point, to determine the difference between the positive phase voltage and the negative phase voltage at each measurement point,An approximation formula that linearly approximates this difference with respect to the distance on the distribution line is obtained by the section determination device. 1 Create separately on both sides of the section determined to have a broken wire, and find the position on the distribution line where the values of the approximate expressions on both sides match each other, A first disconnection point calculation device for outputting data of this position as a disconnection position signal1 withA wire breakage determination processing device is provided.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Hereinafter, a disconnection detecting device for a distribution line according to Embodiment 1 of the present invention will be described with reference to FIG.
In FIG. 1, current / voltage measuring devices 2 to 9 for measuring current / voltage are installed on a distribution line 1. The current / voltage measuring devices 2 to 9 communicate the measured current / voltage to the disconnection determination device 11 through the communication line 10. The current / voltage measuring devices 2 to 9 also convert the measured values into positive phase / reverse phase / zero phase voltages / currents.
FIG. 2 is a diagram for explaining the configuration of processing blocks for processing data by the current / voltage measuring devices 2 to 9 and the disconnection determining device 11.
[0009]
Next, the operation will be described.
FIG. 3 is a diagram for explaining the operation in the case where a disconnection occurs at the a-phase point 99 of the three-phase (a, b, c-phase) distribution line 1 that connects the point 90 and the point 91. In the figure, the transformer symbols are attached to the points 90 and 91, but for convenience of explanation, this is described in order to clarify the section, and what kind of equipment is connected to both ends. It doesn't matter. Now, it is assumed that the voltage on the left side of the a-phase disconnection point 99, that is, the point 90 side is 3 · V larger than the voltage on the right side, that is, the point 91 side. Here, V is an arbitrary number. The voltage of the a-phase, b-phase, and c-phase on the right side of the disconnection point 99 is V_a, V_b, V_cThen, the voltage of the a-phase, b-phase, and c-phase on the left side of the disconnection point is V_a+ (3 ・ V), V_b, V_c  It becomes.
The zero-phase, normal-phase, and reverse-phase voltages on the right side of the disconnection point 99 are respectively expressed as V₀, V₁, V₂Then, the zero-phase voltage, the positive-phase voltage, and the negative-phase voltage on the left side of the disconnection point 99 are respectively expressed as a = e from the definition of the symmetric coordinate method.^{j (2π / 3)}As
(V_a+ 3V + V_b+ V_c) / 3 = V₀+ V --------------- (1)
(V_a+ 3V + aV_b+ a²V_c) / 3 = V₁+ V --------------- (2)
(V_a+ 3V + a²V_b+ aV_c) / 3 = V₂+ V --------------- (3)
[0010]
E phase voltage on the left side of the distribution line_sThe zero-phase, positive-phase, and negative-phase impedances on the left as viewed from the disconnection point 99 are Z_0s, Z_1s, Z_{2s ,}Zero phase current, positive phase current, and negative phase current₀, I₁, I₂If
V₀+ V = −Z_0sI₀   ---------------(Four)
V₁+ V = E_s−Z_1sI₁   ---------------(Five)
V₂+ V = −Z_2sI₂   --------------- (6)
E phase voltage on the right side of the distribution line_rThe zero-phase, positive-phase, and negative-phase impedances on the right side as viewed from the disconnection point of the distribution line_0r, Z_1r, Z_2rIf
V₀ = Z_0rI₀   --------------- (7)
V₁ = E_r+ Z_1rI₁   --------------- (8)
V₂ = Z_2rI₂   --------------- (9)
When the a-phase current is Ia,
I_a = I₀+ I₁+ I₂
Since phase a is disconnected, Ia = 0
I₀+ I₁+ I₂ = 0 --------------- (10)
[0011]
From equations (4), (5), (6)
V₀= -Z_0SI₀-V
V₁= Es-Z_1SI₁-V
V₂= -Z_2SI₂-V
Substituting these into equations (7), (8) and (9)
I₀= -V / (Z_or+ Z_os)
I₁= -V + (E_S-E_r) / (Z_1r+ Z_1s)
I₂= -V / (Z_2r+ Z_2s)
Where Z₀ = Z_{0 S} + Z_0r,
Z₁ = Z_1s + Z_1r,
Z₂ = Z_2s + Z_2r
E_s-E_r= E
Δ = Z₀ Z₁ + Z₁ Z₂ + Z₂ Z₀
And substituting this into equation (10)
0 = -Z₁Z₂V-Z₀ Z₂(VE) -V Z₀Z₁
Than this
V = Z₀ Z₂ E / Δ --------------- (11)
Get.
[0012]
Also,
I₀ =-Z₂ E / Δ --------------- (12)
I₁ = (Z₀ + Z₂ ) E / Δ --------------- (13)
I₂ =-Z₀ E / Δ --------------- (14)
Therefore, from the equations (12), (13), (14), I₁If not = 0, the sum of positive phase current, negative phase current and zero phase current including direction is zero,
I₁ + I₂ + I₀ = 0 & I₁≠ 0 --------------- (15)
By detecting this, it can be easily detected that one line of the distribution line is broken.
[0013]
When the distribution line is ungrounded like the high-voltage distribution line, the zero-phase impedance is much larger than the positive-phase and negative-phase impedances.₀ >> Z₁, Z₀ >> Z₂Therefore, Equation (11) is as follows.
V ≒ 3E Z₂ / (Z₁+ Z₂) --------------- (16)
Similarly, the expressions (12) to (14) are as follows.
I₀ ≒ 0 --------------- (17)
I₁ ≒ E / (Z₁+ Z₂) --------------- (18)
I₂ ≒ − E / (Z₁+ Z₂) --------------- (19)
The calculation described above is executed in the disconnection determination processing device 11a (referred to as a one-wire disconnection determination processing device), and a disconnection detection signal 87 indicating the presence or absence of disconnection is output after the disconnection is detected.
[0014]
Embodiment 2. FIG.
I described in the first embodiment₁ + I₂ + I₀ = 0 & I₁A first method for locating the disconnection point after detecting that there is one disconnection in the distribution line by detecting ≠ 0 will be described.
Positive phase voltage difference before and after the disconnection point from Equation (2) and Equation (11)
V = Z₀ Z₂ E / Δ
Will occur. Therefore, for data from a plurality of measurement points, a difference is calculated between adjacent measurement points. When there is no disconnection in the section between the two measurement points, the positive phase voltage difference is extremely small, and a difference in value close to the above equation occurs between the data of the measurement points on both sides of the section with the disconnection. This makes it possible to determine the section if there is a disconnection point in the section where the maximum difference occurs. The above arithmetic processing is executed by the section determination device 111 (first section determination apparatus) in the disconnection determination processing apparatus 11a, and the determined section is output to the outside as, for example, a disconnection section signal 88.
FIG. 4 shows a plot of the positive phase voltage measured at a plurality of measurement points on this distance (5 points as an example in the figure) with the distance of the distribution line on the horizontal axis. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended to obtain the difference in height between the extension lines on both sides of the disconnection point as the positive phase voltage difference. A disconnection occurs in a section where this difference becomes the value shown in the above equation. If there is little error in measurement in FIG. 4, it is also possible to specify the disconnection position in the measuring device section by accurate calculation. However, since the change due to the distance of the positive phase voltage difference may not be sufficient for specifying the disconnection position, the method after the fifth embodiment described later is suitable for specifying the position in the section.
[0015]
Embodiment 3 FIG.
I described in the first embodiment₁ + I₂ + I₀ = 0 & I₁A second method for locating the disconnection point after detecting that there is one disconnection in the distribution line by detecting ≠ 0 will be described.
Reverse phase voltage difference before and after the disconnection point from Eqs. (3) and (11)
V = Z₀ Z₂ E / Δ
Will occur. Therefore, a difference is obtained between adjacent measurement points of data from a plurality of measurement points. When there is no disconnection in the section between the two measurement points, the negative phase voltage difference is extremely small, and a difference in value close to the above equation occurs between the data of the measurement points on both sides of the section with the disconnection. Accordingly, it is possible to determine the section where the difference is the maximum as the disconnection point. The above arithmetic processing is executed in the section determination device 111 (second section determination apparatus) in the disconnection determination processing device 11a, and the section is output as a disconnection section signal 88, for example.
FIG. 5 shows a plot of the negative phase voltage measured at a plurality of measurement points (5 points as an example in the figure) on the distance with the distance of the distribution line on the horizontal axis. Instead of taking the difference in data between adjacent measurement points, a line connecting each measurement point may be extended to find the difference in height between the extension lines on both sides of the disconnection point. A disconnection occurs in a section where this difference becomes a value shown in the above formula. The specification of the disconnection position in the section is the same as that described in the second embodiment.
[0016]
Embodiment 4 FIG.
I described in the first embodiment₁ + I₂ + I₀ = 0 & I₁A third method for determining the section of the disconnection point after detecting that there is one disconnection in the distribution line by detecting ≠ 0 will be described.
Zero-phase voltage difference before and after the disconnection point from equations (1) and (11)
V = Z₀ Z₂ E / Δ
Will occur. Therefore, the difference between adjacent measurement points is obtained from data from a plurality of measurement points. When there is no disconnection in the section between the two measurement points, the zero-phase voltage difference is extremely small, and a difference in value close to the above equation occurs between the data at the measurement points on both sides of the section with the disconnection. This makes it possible to determine the section of the disconnection point.
The arithmetic processing described above is executed by the section determination device 111 (third section determination apparatus) in the disconnection determination processing device 11a, and the determined section is output to the outside, for example, as a disconnection section signal 88.
FIG. 6 shows a plot of the negative phase voltage measured at a plurality of measurement points (five points as an example in the figure) on the distance with the distance of the distribution line on the horizontal axis. Instead of taking the difference between adjacent measurement points, a line connecting the measurement points may be extended to obtain the difference in height between the extension lines on both sides of the disconnection point. A disconnection occurs in a section where this difference becomes the value shown in the above equation. The specification of the disconnection position in the section is the same as that described in the second embodiment.
[0017]
Embodiment 5 FIG.
A description will be given of a first method for obtaining the disconnection position in the section more accurately after the determination of the disconnection section described in the second to fourth embodiments. From (2), (3) and (11), the difference between the positive and negative phase voltages is the same before and after the disconnection point. By comparing the measurement points, extending the difference value on the graph according to the distance of the distribution line, and obtaining the distance point where the difference coincides, the position of the disconnection point can be pointed.
7 shows the difference between the positive phase voltage and the negative phase voltage, that is, at the left end of the disconnection position 99 in FIG.₁+ V)-(V₂+ V), V at the right end₁-V₂This shows an example of data at each measurement position when this measurement is advanced toward the other end. The position where these values match is the disconnection position. The above calculation processing is executed in the disconnection point calculation device 211 (referred to as the first disconnection point calculation device) in the disconnection determination processing device 11a, and the calculated disconnection point is obtained by, for example, measuring the distance from the nearest measurement point. It is output as a disconnection position signal 89 shown.
[0018]
Embodiment 6 FIG.
A second method for more accurately obtaining the disconnection position in the section will be described. Since the difference between the positive-phase voltage and the zero-phase voltage is the same before and after the disconnection point from Equations (1), (2) and (11), multiple It is possible to point the disconnection point by comparing at the measurement point, extending this on the graph according to the distance, and finding the point where both match.
FIG. 8 shows the difference between the positive phase voltage and the zero phase voltage, that is, at the left end of the disconnection position 99 in FIG.₁+ V)-(V₀+ V), V at the right end₁-V₀This shows an example of data at each measurement position when this measurement is advanced toward the other end. The position where these values match is the disconnection position. The above calculation processing is executed in the disconnection point calculation device 211 (referred to as a second disconnection point calculation device) in the disconnection determination processing device 11a, and the calculated disconnection point is determined by measuring the distance from the nearest measurement point, for example. It is output as a disconnection position signal 89 shown.
[0019]
Embodiment 7 FIG.
A third method for more accurately obtaining the disconnection position in the section will be described. From (1), (3), and (11), the reverse phase voltage and the zero phase voltage are the same before and after the disconnection point, so multiple measurements of the difference between the negative phase voltage and the zero phase voltage before and after the standardized disconnection section It is possible to point the broken point by comparing the points, extending this according to the distance on the graph, and finding a point where both coincide.
9 shows the difference between the negative phase voltage and the zero phase voltage, that is, at the left end of the disconnection position 99 in FIG.₂+ V)-(V₀+ V), V at the right end₂-V₀This shows an example of data at each measurement position when this measurement is advanced toward the other end. The position where these values match is the disconnection position. The above calculation processing is executed in the disconnection point calculation device 211 (referred to as the third disconnection point calculation device) in the disconnection determination processing device 11a, and the calculated disconnection point is determined by measuring the distance from the nearest measurement point, for example. It is output as a disconnection position signal 89 shown.
[0020]
Embodiment 8 FIG.
In Embodiments 5 to 7, the sum of the negative phase current, the positive phase current and the zero phase current including the direction on the distribution line is zero, that is, I₂ + I₁ + I₀ The case where the position of the disconnection in the section is determined after detecting = 0 and determining the section of the disconnection has been described. In the above embodiment, the disconnection position is described as being between the voltage / current measurement devices. However, in reality, it is assumed that there is a disconnection point further outside the measurement device installed at the end of the distribution line. Is done. In the present embodiment, a description will be given of what can be determined even when the disconnection position is outside the measurement point (the end of the distribution line).
From the equations (4), (6) and (12), (14), the positive and negative phase voltages immediately before the disconnection point (to the left of the disconnection point, that is, the power supply side)
V_0s = -Z_0sI₀ = Z_0sZ₂E / Δ = (Z₀Z₂E / Δ} x {Z_0s/ (Z_0s+ Z_0r)} ------- (20)
V_2s = -Z_2sI₂ = Z₀Z_2sE / Δ = (Z₀Z₂E / Δ} x {Z_2s/ (Z_2s+ Z_2r)} -------(twenty one)
Because
Z_0s / Z_0r = Z_2s / Z_2r That is, if the ratio of the negative phase impedance and the zero phase impedance viewed from the disconnection point to the left side is equal to the ratio of the negative phase impedance and the zero phase impedance viewed from the disconnection point to the right side, the zero phase voltage V immediately before the disconnection point_0s And reverse phase voltage V just before the disconnection point_2sAre equal.
[0021]
On the other hand, from equations (7), (9) and (12), (14), the positive and negative voltages immediately after the disconnection point (to the right of the disconnection point, that is, the load side) are
V_0r = Z_0rI₀ = -Z_0rZ₂E / Δ = {-Z₀Z₂E / Δ} x {Z_0r/ (Z_0s+ Z_0r)} ----(twenty two)
V_2r = Z_2rI₂ = -Z₀Z_2rE / Δ = {-Z₀Z₂E / Δ} x {Z_2r/ (Z_2s+ Z_2r)} ----(twenty three)
Because
Z_0s / Z_0r = Z_2s / Z_2r That is, if the ratio of the negative phase impedance and the zero phase impedance viewed from the disconnection point to the left side is equal to the ratio of the negative phase impedance and the zero phase impedance viewed from the disconnection point to the right side, the zero phase voltage V immediately after the disconnection point_{0 r} And reverse phase voltage V immediately after the disconnection point_{2 r}Are equal.
By utilizing this fact, it is possible to obtain a device capable of locating the disconnection point even when the disconnection is outside the voltage / current detecting device.
The above calculation processing is executed in the disconnection point calculation device 211 (referred to as a fourth disconnection point calculation device) in the disconnection determination processing device 11a, and the calculated disconnection point is determined by measuring the distance from the nearest measurement point, for example. It is output as a disconnection position signal 89 shown.
FIG. 10 shows an example of the zero-phase voltage and the negative-phase voltage measured at each measurement point arranged on the distance on the horizontal axis, and shows a case where a position where both coincide with each other is extended.
[0022]
Embodiment 9 FIG.
In the first to eighth embodiments, the detection in the case of the disconnection of one line has been described. In the following description of the present embodiment, a case where two wires are disconnected at one point will be described.
FIG. 11 shows that two-wire breakage occurred in the b-phase and c-phase of the distribution line. When a two-wire break occurs at the same point in the distribution lines b and c, the voltage difference between both sides of the b-phase break point at the break points 199 and 299 when the b and c phases are disconnected is 3U._b The voltage difference between both sides of the c-phase disconnection point is 3U._cAnd
That is, the voltage on the left side of the b-phase disconnection point 199 is 3U higher than the voltage on the right side._bLarge, the left side voltage of the c-phase disconnection point 299 is 3U than the right side voltage_cSuppose it's big. The voltage of a phase, b phase, and c phase on the right side of the disconnection point is V_a, V_b, V_cThen, the voltages of the a-phase, b-phase, and c-phase on the left side of the disconnection points 199 and 299 are V_a, V_b+ 3 U_b, V_c + 3 U_cIt becomes.
Zero-phase, positive-phase, and negative-phase voltages on the right side of the disconnection point 199 are V_{0 ,}V₁, V₂Then, the zero-phase, normal-phase, and reverse-phase voltages on the left side of the disconnection point 199 are expressed by the symmetric coordinate method as follows: a = e^{j (2π / 3)}As
(V_a+ V_b+3 U_b + V_c+3 U_c) / 3 = V₀+ U_b + U_c   ---------------(twenty four)
(V_a+ aV_b+3 aU_b + a²V_c+3 a² U_c) / 3 = V₁+ aU_b + a²U_c   ------(twenty five)
(V_a+ a²V_b+3 a²U_b + aV_c+3 aU_c) / 3 = V₂+ a²U_b + aU_c   ------ (26)
Is established.
[0023]
E phase voltage on the left side of the distribution line_sZ, zero phase, positive phase, and negative phase impedance when looking at the left side from the disconnection point_0s, Z_1s, Z_2sAnd zero-phase, normal-phase, and reverse-phase currents as I₀, I₁, I₂If
V₀+ U_b + U_c =-Z_0sI₀   --------------- (27)
V₁+ aU_b + a²U_c = E_s -Z_1sI₁   ---------- (28)
V₂+ a²U_b + aU_c =-Z_2sI₂   ------------- (29)
E phase voltage on the right side of the distribution line_rThe zero-phase, positive-phase, and negative-phase impedances on the right side as viewed from the disconnection point of the distribution line_0r, Z_1r, Z_2rIf
V₀= Z_0rI₀   --------------- (30)
V₁= E_r + Z_1rI₁   ---------- (31)
V₂= Z_2rI₂   --------------- (32)
b phase and c phase are disconnected, so I_b= 0, I_c= 0
I₀= I₁= I₂= I_a/ 3 --------------- (33)
[0024]
(27), (28), (29)
V₀+ V₁+ V₂ = −Z_0sI₀ + E_s − Z_1sI₁ − Z_2sI₂   --------------- (34)
Substituting Equations (30), (31), and (32) into Equation (34) and using Equation (33)
I₀ = I₁= I₂= E / (Z₀+ Z₁+ Z₂) --------------- (35)
Where E = E_s−E_r, Z₀= Z_0s+ Z_0r, Z₁= Z_1s+ Z_1r, Z₂= Z_2s+ Z_2r
Positive phase voltage difference U before and after disconnection₁, Reverse phase voltage difference U₂, Zero phase voltage difference U₀Each
U₁= (E_s -Z_1sI₁)-(E_r+ Z_1rI₁) = E (Z₀+ Z₂) / (Z₀+ Z₁+ Z₂------- (36)
U₂=-Z_2sI₂ -Z_2rI₂ = -E Z₂/ (Z₀+ Z₁+ Z₂) --------------- (37)
U₀=-Z_0sI₀ -Z_0rI₀ = -E Z₀/ (Z₀+ Z₁+ Z₂) --------------- (38)
From equations (36), (37), (38)
U₁ + U₂ + U₀  = 0 --------------- (39)
From equation (39), the positive phase voltage difference U at the left measurement point₁If = 0, the difference U between the positive phase voltage at the left measurement point and the positive phase voltage at the right measurement point U₁ Difference between the negative phase voltage and the zero phase voltage at the left measurement point, and the sum of the negative phase voltage and the zero phase voltage at the right measurement point U₂ + U₀ Are equal in magnitude and opposite in sign, i.e.
U₁= − (U₂ + U₀) = U & U₁≠ 0 --------------- (40)
Where U = E (Z₀+ Z₂) / (Z₀+ Z₁+ Z₂)
Then, it can be detected that a two-wire disconnection exists between the left and right measurement points.
To help understanding, the above state is illustrated in FIG.
[0025]
Since the high-voltage distribution line is ungrounded, the zero-phase impedance is much larger than the positive-phase impedance and the negative-phase impedance.₀ >> Z₁, Z₀ >> Z₂Therefore, equations (36), (37), and (38) are as follows.
U₁ ≒ E --------------- (41)
U₂ ≒ 0 --------------- (42)
U₀ ≒ −E ------------- (43)
The calculation described above is executed in the disconnection determination processing device 11a (referred to as “two disconnection determination processing device”), and after detecting the disconnection, a disconnection detection signal 87 indicating the presence or absence of disconnection is output.
[0026]
Embodiment 10 FIG.
A method of locating the section of the disconnection position after detecting that there is a disconnection at the same point in the ninth embodiment (referred to as a fourth method in order to distinguish from the case of a one-wire disconnection) will be described.
Positive phase voltage difference before and after the disconnection point from equation (36)
U₁= E (Z₀+ Z₂) / (Z₀+ Z₁+ Z₂) Occurs.
Therefore, for data from a plurality of measurement points, a difference is obtained between adjacent measurement points. When there is no disconnection in the section between the two measurement points, the positive phase voltage difference is extremely small, and a difference in value close to the above difference occurs between the data of the measurement points on both sides of the section with the disconnection. Thus, it is possible to evaluate the section if there is a disconnection point in the section where the maximum difference occurs. The above arithmetic processing is executed by the section determination device 111 (fourth section determination apparatus) in the disconnection determination processing device 11a, and the determined section is output to the outside, for example, as a disconnection section signal 88.
FIG. 13 shows a plot of positive phase voltages measured at a plurality of measurement points (in the figure, five points as an example) on the horizontal axis with the distance of the distribution line on the horizontal axis. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended to obtain the difference in height between the extension lines on both sides of the disconnection point as the positive phase voltage difference. A disconnection occurs in a section where this difference becomes the value shown in the above equation. If there is little error in measurement in FIG. 13, it is also possible to specify the disconnection position in the measuring device section by accurate calculation. However, since the change due to the distance of the positive phase voltage difference may be insufficient for specifying the disconnection position, the method of the thirteenth embodiment described later is suitable for specifying the position in the section.
[0027]
Embodiment 11 FIG.
A fifth method for locating the 2-wire disconnection section at the same point will be described.
Reverse phase voltage difference before and after the disconnection point from equation (37)
U₂=-E Z₂/ (Z₀+ Z₁+ Z₂) Occurs.
Therefore, for data from a plurality of measurement points, a difference is obtained between adjacent measurement points. When there is no disconnection in the section between the two measurement points, the negative phase voltage difference is very small, and a difference in value close to the above difference occurs between the data of the measurement points on both sides of the section with the disconnection. Thus, it is possible to evaluate the section if there is a disconnection point in the section where the maximum difference occurs. The above arithmetic processing is executed by the section determination device 111 (fifth section determination apparatus) in the disconnection determination processing device 11a, and the determined section is output to the outside, for example, as a disconnection section signal 88.
FIG. 14 shows a plot of the negative phase voltage measured at a plurality of measurement points (five points in the figure as an example) on the distance with the distance of the distribution line on the horizontal axis. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended to obtain the difference in height between the extension lines on both sides of the disconnection point as a reverse phase voltage difference. A disconnection occurs in a section where this difference becomes the value shown in the above equation. The specification of the disconnection position in the section is the same as that described in the tenth embodiment.
[0028]
Embodiment 12 FIG.
A sixth method for locating a section where two wires are disconnected at the same point will be described.
Zero phase voltage difference before and after the disconnection point from equation (38)
U₀=-E Z₀/ (Z₀+ Z₁+ Z₂) Occurs.
Therefore, for data from a plurality of measurement points, a difference is obtained between adjacent measurement points. When there is no disconnection in the section between the two measurement points, the zero-phase voltage difference is extremely small, and a difference close to the above difference occurs between the data at the measurement points on both sides of the section with the disconnection. Thus, it is possible to evaluate the section if there is a disconnection point in the section where the maximum difference occurs. The above arithmetic processing is executed in the section determination device 111 (sixth section determination device) in the disconnection determination processing device 11a, and the determined section is output to the outside, for example, as a disconnection section signal 88.
FIG. 15 shows a plot of the zero-phase voltage measured at a plurality of measurement points (five points in the figure as an example) on the distance with the distance of the distribution line on the horizontal axis. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended to obtain the difference in height between the extension lines on both sides of the disconnection point as the zero-phase voltage difference. A disconnection occurs in a section where this difference becomes the value shown in the above equation. The specification of the disconnection position in the section is the same as that described in the tenth embodiment.
[0029]
Embodiment 13 FIG.
In the tenth to twelfth embodiments, a method of determining the disconnection position in the section more accurately after the section where the two lines are disconnected will be described. From the equation (39), the sum of the positive phase voltage difference, the negative phase voltage difference and the zero phase voltage difference including the direction before and after the disconnection point is equal to zero. Therefore, as shown in FIG. 16, the sum V of the positive phase voltage, the negative phase voltage and the zero phase voltage before and after the disconnection point.₁ + V₂ + V₀  Is measured at multiple measurement points. And if the line which connected the measured value sequentially from the both ends of a distribution line is extended, the point which shows the same value will be calculated | required. This point is the same point 2 wire disconnection point.
The above calculation processing is executed in the disconnection point calculation device 211 (referred to as the fifth disconnection point calculation device) in the disconnection determination processing device 11a, and the calculated disconnection point is determined by measuring the distance from the nearest measurement point, for example. It is output as a disconnection position signal 89 shown.
[0030]
【The invention's effect】
As described above, according to the present invention, the voltage / current at a plurality of locations in the distribution line is converted into a normal phase voltage, a negative phase voltage, a zero phase voltage, a positive phase current, a negative phase current, and a zero phase current for processing. Since it is configured as described above, it is possible to determine the failure section of the one-line disconnection of the distribution line and the two-wire disconnection at the same point, and further, it is possible to determine the fault position in the section. In addition, even when a distributed power source exists on the terminal side of the distribution line, a device capable of locating a failure section and a failure point by unified handling can be obtained. Usually, the high-voltage distribution line is ungrounded at the neutral point, but even if there is a ground impedance, the failure section and the failure point can be determined by unified handling.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a diagram for explaining the configuration and arrangement of a distribution line disconnection detecting device in all embodiments of the present invention.
FIG. 2 is a diagram for explaining internal configurations and connections of a disconnection determination device and a current / voltage measurement device.
FIG. 3 is a diagram for explaining a disconnection position of a distribution line.
FIG. 4 is a diagram for explaining the operation of a distribution line disconnection detection apparatus according to a second embodiment of the present invention.
FIG. 5 is a diagram for explaining the operation of a distribution line disconnection detection apparatus according to a third embodiment of the present invention.
FIG. 6 is a diagram for explaining the operation of a distribution line disconnection detection apparatus according to a fourth embodiment of the present invention.
FIG. 7 is a diagram for explaining the operation of the distribution line disconnection detection apparatus according to the fifth embodiment of the present invention;
FIG. 8 is a diagram for explaining the operation of a distribution line disconnection detection apparatus according to a sixth embodiment of the present invention.
FIG. 9 is a diagram for explaining the operation of the distribution line disconnection detecting device according to the seventh embodiment of the present invention;
FIG. 10 is a diagram for explaining the operation of a distribution line disconnection detection apparatus according to an eighth embodiment of the present invention.
FIG. 11 is a diagram for explaining a disconnection position of a distribution line in the ninth to thirteenth embodiments.
FIG. 12 is a diagram for explaining the operation of the distribution line disconnection detection apparatus according to the ninth embodiment of the present invention;
FIG. 13 is a diagram for explaining the operation of the distribution line disconnection detecting device according to the tenth embodiment of the present invention;
FIG. 14 is a diagram for explaining the operation of the distribution line disconnection detecting device according to the eleventh embodiment of the present invention;
FIG. 15 is a diagram for explaining the operation of the distribution line disconnection detection apparatus according to the twelfth embodiment of the present invention;
FIG. 16 is a diagram for explaining the operation of the distribution line disconnection detection apparatus according to the thirteenth embodiment of the present invention;
[Explanation of symbols]
1 distribution line, 2-9 device for measuring current and voltage,
10 communication line, 11 disconnection determination device,
11a Disconnection determination processing device (1-wire disconnection determination processing device or 2-wire disconnection determination processing device),
87 Disconnection detection signal, 88 Disconnection section signal, 89 Disconnection position signal,
111 1st-6th area determination apparatus,
211 1st-5th disconnection point arithmetic unit.

Claims (5)

It is arranged at the measurement points set in each of the sections of the distribution line divided into a plurality of sections, detects the voltage and current of the distribution lines at the measurement points, and the voltage of the normal phase, reverse phase, zero phase And a sensor that calculates current and converts it to data, and transmits this data to the outside via a communication line
The data is received from each sensor of the plurality of sections via the communication line, the sum of the positive phase current value, the negative phase current value, and the zero phase current value of the distribution line is calculated, and the positive phase current When the value is not zero and the sum of the positive phase current value, the negative phase current value, and the zero phase current value is zero, a disconnection detection signal is output to indicate that there is one disconnection in the distribution line. And
Any one of the difference of the positive phase voltage, the difference of the negative phase voltage, or the difference of the zero phase voltage between the measurement points at both ends of each of the intervals is obtained for all the intervals, and this difference is the largest. A section determination device that determines that there is a disconnection of the one line in a section that is large and outputs a disconnection section signal , and
Based on the positive-phase voltage and the negative voltage at each measurement point of the said obtains the difference between the positive phase voltage and the negative-phase voltage of each measurement point, with respect to the distance the difference of the power distribution line Create an approximate expression for linear approximation separately on both sides of the section determined that there is a disconnection of the one line by the section determination device, find the position on the distribution line where the values of the approximate expressions on both sides match each other , A distribution line disconnection detection device comprising a one-wire disconnection determination processing device having a first disconnection point computing device that outputs data of this position as a disconnection position signal. It is arranged at the measurement points set in each of the sections of the distribution line divided into a plurality of sections, detects the voltage and current of the distribution lines at the measurement points, and the voltage of the normal phase, reverse phase, zero phase And a sensor that calculates current and converts it to data, and transmits this data to the outside via a communication line
The data is received from each sensor of the plurality of sections via the communication line, the sum of the positive phase current value, the negative phase current value, and the zero phase current value of the distribution line is calculated, and the positive phase current When the value is not zero and the sum of the positive phase current value, the negative phase current value, and the zero phase current value is zero, a disconnection detection signal is output to indicate that there is one disconnection in the distribution line. And
Determined for the positive difference between the phase voltage or the difference between the negative-phase voltage or all of the section of any one of the difference between the zero-phase voltage, between the measuring points at the ends of each section of the, the difference is most A section determination device that determines that there is a disconnection of the one line in a section that is large and outputs a disconnection section signal , and
Based on the positive phase voltage and the zero phase voltage at each measurement point, the difference between the positive phase voltage and the zero phase voltage at each measurement point is obtained, and this difference is calculated with respect to the distance on the distribution line. Create an approximate expression for linear approximation separately on both sides of the section determined that there is a disconnection of the one line by the section determination device, find the position on the distribution line where the values of the approximate expressions on both sides match each other, A distribution line disconnection detection device comprising a one-wire disconnection determination processing device having a second disconnection point calculation device that outputs data of this position as a disconnection position signal. It is arranged at the measurement points set in each of the sections of the distribution line divided into a plurality of sections, detects the voltage and current of the distribution lines at the measurement points, and the voltage of the normal phase, reverse phase, zero phase And a sensor that calculates current and converts it to data, and transmits this data to the outside via a communication line
The data is received from each sensor of the plurality of sections via the communication line, the sum of the positive phase current value, the negative phase current value, and the zero phase current value of the distribution line is calculated, and the positive phase current When the value is not zero and the sum of the positive phase current value, the negative phase current value, and the zero phase current value is zero, a disconnection detection signal is output to indicate that there is one disconnection in the distribution line. And
Determined for the positive difference between the phase voltage or the difference between the negative-phase voltage or all of the section of any one of the difference between the zero-phase voltage, between the measuring points at the ends of each section of the, the difference is most A section determination device that determines that there is a disconnection of the one line in a section that is large and outputs a disconnection section signal , and
Based on the negative phase voltage and the zero phase voltage at each measurement point, the difference between the negative phase voltage and the zero phase voltage at each measurement point is obtained, and this difference is calculated with respect to the distance on the distribution line. Create an approximate expression for linear approximation separately on both sides of the section determined that there is a disconnection of the one line by the section determination device, find the position on the distribution line where the values of the approximate expressions on both sides match each other, A distribution line disconnection detection device comprising a one-wire disconnection determination processing device having a third disconnection point calculation device that outputs data of this position as a disconnection position signal. It is arranged at the measurement points set in each of the sections of the distribution line divided into a plurality of sections, detects the voltage and current of the distribution lines at the measurement points, and the voltage of the normal phase, reverse phase, zero phase And a sensor that calculates current and converts it to data, and transmits this data to the outside via a communication line
The data is received from each sensor of the plurality of sections via the communication line, the sum of the positive phase current value, the negative phase current value, and the zero phase current value of the distribution line is calculated, and the positive phase current When the value is not zero and the sum of the positive phase current value, the negative phase current value, and the zero phase current value is zero, a disconnection detection signal is output to indicate that there is one disconnection in the distribution line. And
Determined for the positive difference between the phase voltage or the difference between the negative-phase voltage or all of the section of any one of the difference between the zero-phase voltage, between the measuring points at the ends of each section of the, the difference is most A section determination device that determines that there is a disconnection of the one line in a section that is large and outputs a disconnection section signal , and
Based on the negative phase voltage and the zero phase voltage at each of the measurement points, for each of the negative phase voltage and the zero phase voltage , create an approximate expression that linearly approximates the distance on the distribution line, Find the position on the distribution line where the value of the approximate expression of the negative phase voltage and the value of the approximate expression of the zero phase voltage match each other,
A distribution line disconnection detection device comprising a one-wire disconnection determination processing device having a fourth disconnection point calculation device that outputs data of this position as a disconnection position signal. It is arranged at the measurement points set in each of the sections of the distribution line divided into a plurality of sections, detects the voltage and current of the distribution lines at the measurement points, and the voltage of the normal phase, reverse phase, zero phase And a sensor that calculates current and converts it to data, and transmits this data to the outside via a communication line
Wherein the respective sensors of a plurality segments via the communication line to receive the data, from the positive-phase voltage values and the negative-phase voltage value and the zero-phase voltage values at two neighboring one of said measurement points of said power distribution line, said The difference U ₁ between the two points of the positive phase voltage value at each of the two points and the difference (U ₂ + U ₀₎ of the sum of the negative phase voltage value and the zero phase voltage value at each of the two points. ) , U ₁ is not zero, and
When U ₁ = − (U ₂ + U ₀ ), a disconnection detection signal indicating that there is a disconnection of two wires at the same point on the distribution line is output ,
Any one of the difference of the positive phase voltage, the difference of the negative phase voltage, or the difference of the zero phase voltage between the measurement points at both ends of each of the above intervals is obtained for all the intervals, and this difference is the largest. A section determination device that determines that there is a disconnection of the two wires in the section and outputs a disconnection section signal ; and
It calculates the sum of the positive-phase voltage values and the negative-phase voltage value and the zero-phase voltage values for each measurement point of the said approximation equation to linearly approximate the sum with respect to the distance of the distribution line by the section determination unit 2 Create separately on both sides of the section determined to have a broken line, find the position on the distribution line where the values of the approximate expressions on both sides match each other,
A distribution line disconnection detection device comprising a two-wire disconnection determination processing device having a fifth disconnection point calculation device that outputs data of this position as a disconnection position signal.

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