KR101145496B1 - Apparatus for detecting roof current in distribution automation system and method thereof - Google Patents

Abstract

The present invention relates to an apparatus and method for measuring a loop current of a distribution automation system, and more particularly, to a method and apparatus for measuring a loop current of a distribution automation system, An algae calculation unit for calculating algae at both ends of the normally open point switch by using the measured values inputted through the input unit; A loop current calculation unit for calculating a power value due to a loop current formed at both ends of the normally open point switch when connecting to a distribution line, and a control unit for comparing the power value by the loop current calculated by the loop current calculation unit with a threshold value, And a loop state determination unit for determining a loop state from the resultant value.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus for measuring a loop current of a distribution automation system,

The present invention relates to an apparatus and method for measuring the loop current of a distribution automation system, and more particularly, to an apparatus and method for measuring a loop current in a distribution automation system, And more particularly, to a loop current measuring apparatus and method for a distribution automation system for measuring a loop current from an algae value.

Conventionally, the system operator merely computes the amount of current by adding or subtracting the load current to each power distribution line, and performs the coordinated operation for checking the uninterruptible operation and the distribution automation device with the power distribution line. Of the total.

Particularly, in the related art, in order to check the uninterruptible operation of the distribution line and the automatic control apparatus of the distribution line, when the load is switched to the distribution line, the connection load inspection of two different distribution lines is simply calculated by summing the loads of the two distribution lines, There was no way to confirm the reduction.

An object of the present invention is to provide a system and method for automatically estimating a load increase situation caused by algae when two different distribution lines are connected to a distribution line of a distribution automation system for checking an uninterruptible operation and a distribution automation apparatus, The present invention provides a loop current measuring apparatus and method for a distribution automation system that eliminates work load and prevents an electricity sales loss due to a power outage of a human error and a business loss of a customer.

According to another aspect of the present invention, there is provided an apparatus for measuring a loop current of a distribution automation system, the apparatus comprising: A tidal current calculation unit for calculating the tidal currents at both ends of the normally open point switch by using the measured value input through the input unit; A loop current calculation unit for calculating a power value due to the loop currents formed at both ends of the normally open point switch when coupling to different power distribution lines at the time of connection to the power distribution line, And a loop state determination unit for determining a loop state from the result of comparison.

The measured value may include at least one of a primary voltage, a phase, a load and an impedance of the main transformer, a secondary voltage of the main transformer, a phase, a load, an impedance, and an impedance and a load on the power distribution line.

Wherein the algae calculation unit calculates the algae value due to the phase difference between both ends of the normally open point switch and the algae value due to the load difference across the normally open point switch.

The loop current calculation unit calculates a loop current value based on the sum of the algae value calculated by the phase difference between the both ends of the normally open point switch and the algae value due to the load difference between the normally open point switch and the value calculated by the algae calculation unit, And a power value due to the loop current formed at both ends of the point switch is calculated.

The loop current calculation unit calculates a power value due to the loop current from the main transformer primary line to the main transformer and a power value due to the loop current to the secondary line of the main transformer from both ends of the normally open point switch.

Wherein the power value due to the loop current of the main transformer primary distribution line is calculated by a sum of the algebraic value based on the phase difference calculated by the primary side of the main transformer and the alga value based on the load difference, And a value obtained by adding the value

The power value due to the loop current of the secondary side power distribution line is calculated by a sum of the algebraic value based on the phase difference calculated by the secondary side of the main transformer and the alga value based on the load difference and the load value on the secondary side power line side of the main transformer And is a sum value.

An output for outputting at least one of a value input through the input unit, a tidal value calculated from a value input through the input unit, a power value by a loop current calculated from the tidal value, And further comprising:

According to another aspect of the present invention, there is provided a method for measuring a loop current of a distribution automation system, the method comprising the steps of: Calculating the algae at both ends of the normally open point switch by using the measured values, calculating the algae value at the step of calculating the algae, Calculating a power value based on a loop current formed at both ends of the normally open-ended switch when the loop current is coupled to the loop current, calculating a power value by the loop current, comparing the power value with the loop current, And determining a loop state from the resultant value.

The measured value may include at least one of a primary voltage, a phase, a load and an impedance of the main transformer, a secondary voltage of the main transformer, a phase, a load, an impedance, and an impedance and a load on the power distribution line.

Wherein the step of calculating the algae calculates the algae value by the phase difference between the both ends of the normally open point switch and the algae value by the load difference between both ends of the normally open point switch.

The step of calculating the power value by the loop current includes a step of calculating the sum of the value of the alga by the phase difference at both ends of the normally open point switch and the value of the alga by the load difference at both ends of the normally open point switch, And calculating a power value based on a loop current formed at both ends of the normally open-point switch from the load value on the power distribution line.

Wherein the step of calculating the loop current is characterized by calculating a power value due to the loop current from the main transformer primary line to the main transformer and a power value from the loop current to the secondary line of the main transformer at both ends of the normally open- do.

Wherein the power value due to the loop current of the main transformer primary distribution line is calculated by a sum of the algebraic value based on the phase difference calculated by the primary side of the main transformer and the alga value based on the load difference, And a value obtained by adding the value

The power value due to the loop current of the secondary side power distribution line is calculated by a sum of the algebraic value based on the phase difference calculated by the secondary side of the main transformer and the alga value based on the load difference and the load value on the secondary side power line side of the main transformer And is a sum value.

And outputting at least one of a tidal value calculated from the measured value, a power value calculated by the tidal current calculated from the tidal value, and loop state information to the distribution line.

According to the present invention, in order to check the uninterruptible operation of the distribution automation system and the distribution automation equipment, it is possible to automatically predict the load increase situation caused by the algae when connecting to two different distribution lines, There is an advantage of solving the burden.

In addition, the present invention automatically predicts the load increase due to algae when connecting two different distribution lines to check the uninterruptible operation and distribution automation equipment with the distribution line of the distribution automation system, There is an advantage to minimize electricity sales loss and customer's business loss.

1 is a block diagram for explaining a configuration of an apparatus for measuring a loop current of a distribution automation system according to the present invention.
FIG. 2 is an exemplary diagram of a loop current measuring apparatus of a distribution automation system according to the present invention, which is referred to in calculating an alga value by a phase difference.
3 is an exemplary diagram for referring to the calculation of the algae value by the load difference in the loop current measuring apparatus of the distribution automation system according to the present invention.
Figs. 4 and 5 are diagrams illustrating algae values and loop current values calculated from measured values when interconnecting different distribution lines in a distribution automation system. Fig.
6 is a flowchart showing an operational flow for a loop current measurement method of a distribution automation system according to the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram for explaining a configuration of an apparatus for measuring a loop current of a distribution automation system according to the present invention.

1, an apparatus for measuring the loop current of a distribution automation system according to the present invention includes an input unit 110, an output unit 120, a control unit 130, a storage unit 140, a bird's current calculation unit 150, A loop current calculation unit 160, and a loop state determination unit 170.

The input unit 110 receives a control command from an administrator. Also, the input unit 110 receives the measured values from the respective lines according to the operation of the normally open-point switch when connecting the different distribution lines in the distribution automation system.

At this time, the value input through the input unit 110 corresponds to the voltage, phase, load, and impedance of the main transformer on the power distribution line, impedance, load, impedance, and impedance on the secondary side of the main transformer, .

The output unit 120 outputs the operation state of the loop current measuring apparatus through the screen of the output unit 120. [ The output unit 120 outputs the value input through the input unit 110 and the processed values of the loop current measuring apparatus, that is, the current value, the current value of the loop, and the loop status information to the corresponding power line.

The control unit 130 controls each sub-operation.

The storage unit 140 stores the mains voltage, phase, load, and impedance of the main transformer input through the input unit 110, the impedance, the load, and the like on the secondary voltage, phase, load, impedance and distribution line of the main transformer .

When the normally open point switch is operated in connection with different distribution lines in the distribution automation system, the algae calculation unit 150 calculates the voltage, phase, load, and impedance of the main transformer stored in the storage unit 140, Calculate the algae using the voltage, phase, load, impedance, and impedance on the power line, load.

At this time, the algae calculation unit 150 calculates the algae value due to the phase difference and the algae value due to the load difference, taking into consideration that the algae flow due to the phase difference and the algae flow due to the load difference.

Reference is made to the embodiments of Figs. 2 and 3 for a specific explanation of calculating the bird value at the bird's diagonal calculation section 150. Fig.

The loop current calculation unit 160 calculates the power value based on the loop current using the algae value calculated by the alga current calculation unit 150. [ The loop current calculation unit 160 calculates the power value by the loop current based on the sum of the algae value by the phase difference and the algae value by the load difference and the load value on the distribution line.

At this time, the loop current calculation unit 160 calculates the power value due to the loop current of the main transformer primary distribution line and the power value due to the loop current to the secondary distribution line of the main transformer, respectively.

For example, the loop current calculation section 160 adds the value of the bird by the phase difference and the value of the bird by the load difference and the load value on the primary side power distribution line, Lt; / RTI >

Further, the loop current calculation section 160 adds the value of the algebraic value due to the phase difference and the algebraic value due to the load difference, and the value of the load on the secondary side power line to add the power value due to the loop current to the secondary side power line of the main transformer .

The loop state determination unit 170 compares the power value due to the loop current of the main transformer primary distribution line and the power value due to the loop current to the secondary distribution line of the main transformer calculated by the loop current calculation unit 160 with a threshold value And determines the loop state from the resultant value.

At this time, if the power value due to the loop current of the main transformer primary side distribution line and the power value due to the loop current to the secondary side power distribution line of the main transformer are less than the mode threshold value, It is determined that a loop can be made at both ends of the normally open point switch, and the result is output to the output unit 120.

On the other hand, if at least one of the power value due to the loop current on the primary side power line to the main transformer and the power value due to the loop current to the secondary side power line of the main transformer is equal to or greater than the threshold value, It is determined that the loop can not be looped at both ends of the normally open-ended switch, and the result is output to the output unit 120.

Here, the threshold value is preferably 14 x 0.9, but is not limited thereto.

Thus, the manager can easily and quickly check the load increase amount to the power distribution line when the normally open point switch is operated from the loop state output through the output unit 120. [

2 is a diagram referred to explain the operation of calculating the algae by the phase difference.

As shown in FIG. 2, the algae calculation unit 150 calculates the algae by the phase difference in consideration of the flow of the algae due to the phase difference when the normally-open-point switch 5 is turned on.

The equation for calculating the algae ΔP _A due to the phase difference is shown in the following equation (1).

Where V1 is the primary main transformer voltage (V) and V2 is the secondary main transformer voltage (V), where V1xV2 = 10,000. Where X1 is the impedance of the primary main transformer, Xtb is the impedance of the secondary main transformer, Za is the primary preferred impedance, and Zb is the impedance of the primary main transformer. And is a value representing the secondary-side line impedance.

The calculation of the algae by the phase difference can be implemented in the form of a program, and the code applied to the program in the case of implementation by the program is as follows.

double dP1, dP2, dPI = 3.141592654 / 180.0;

dP1 = 10000 * sin ((dPhase1-dPhase2) * dPI) / (pMTR-> m_dLCC_Value [1] + pMTR2-> m_dLCC_Value [1] + dXp1 + dXp2);

dP2 = dP1 * -1;

3 is a diagram referred to explain the algae calculation operation by the load difference.

As shown in FIG. 3, the algae calculation unit 150 calculates the algae by the load difference in consideration of the flow of the algae by the load difference when the normally-open-point switch 5 is turned on.

The equation for calculating the alga P _B due to the load difference is shown in the following equation (2).

Where Ma is the primary main transformer impedance, Xtb is the impedance of the secondary main transformer, Ma is the primary main transformer load (mW), Mb is the secondary main transformer load (mW), Za is the primary line impedance, And is a value representing the secondary-side line impedance.

The calculation of the algae by the load difference may be implemented in the form of a program, and the code applied to the program in the case of implementation by the program is as follows.

double dPL1, dPL2, dDL1, dDL2;

dPL1

pMTR-> m_dLCC_Value [1] -pMTR-> m_dMV * pMTR-> m_dLCC_Value [1]) / (pMTR-> m_dLCC_Value [1] + pMTR2-> m_dLCC_Value [1] + dXp1 + dXp2) ;

dPL2 = dPL1 * -1;

dDL1 = (sqrt (3.) * 22900 * pCB-> dLoad / 1000000.0) + (dP1 + dPL1);

dDL2 = (sqrt (3.) * 22900 * pCB2-> dLoad / 1000000.0) + (dP2 + dPL2);

Of course, in the case of implementing the above-described algebraic calculation by the phase difference and the algae calculation by the load difference in a program form, the determination of the loop state by the loop current calculation at both ends of the normally open- At this time, the code applied to the program is as follows.

int nDist = 0;

double dAA1, dAA2;

dAA1 = pCB-> m_nRelay_ratio * pCB-> m_dRelay_tap * 0.9;

dAA2 = pCB-> m_nRelay_ratio * pCB2-> m_dRelay_tap * 0.9;

Figs. 4 and 5 are diagrams illustrating algae values and loop current values calculated from measured values when interconnecting different distribution lines in a distribution automation system. Fig.

First, FIG. 4 shows measured values when interconnecting different distribution lines in a distribution automation system. More specifically, the values measured at the substations A and B in connection with the distribution lines of the substations A and B are shown.

As shown in FIG. 4, the phase angle of the distribution line measured at the substation A is -13 °, and the distribution line (D / L) is cc and the main transformer (M. tr) applied to the distribution line is # 3. The load of the main transformer M. tr is 6.6 mW, the load of the distribution line D / L is 1.08 mW, the impedance of the main transformer M. tr is 33.13, and the impedance of the distribution line D / 11.85, and the emergency operation capacity is 14mW.

On the other hand, the phase angle of the distribution line measured at substation B is -12.5 °, and the corresponding distribution line (D / L) is ff and the main transformer (M. tr) applied to the distribution line is # 3. The load of the main transformer (M. tr) is 18.6 mW, the load of the distribution line (D / L) is 2.74 mW, the impedance of the main transformer (M. tr) is 35.89 and the impedance of the distribution line (D / L) 105.89, and the emergency operation capacity is 14mW.

4, when the values measured at the substations A and B are shown in FIG. 4 when the substation A and the substation B are connected to each other, the results of determining the loop condition for the substations A and B are shown in FIG.

5, in connection with substation B, the algae value due to the phase difference of the substation A is 0.46 mW, the algae value due to the load difference is 1.98 mW, and the algae value due to the phase difference and the algae value due to the load difference The sum is 2.4mW. In addition, the load of the distribution line (D / L) cc is 5.2 mW when connected to the distribution line of the substation A and the substation B.

Therefore, the loop state determination unit 170 determines the loop state from the sum of the algebraic value due to the phase difference and the alga value due to the load difference in the substation A plus the load of the distribution line (D / L) cc. At this time, the sum of the algae value and the alga value by the load difference is 2.4 mW, and the value of the load of the distribution line (D / L) cc plus 5.2 mW is 7.7 mW, which is smaller than the threshold value 14 × 0.9 = 12.6 mW It is determined that the loop is possible.

On the other hand, in connection with the substation A, the algae value due to the phase difference of the substation B is -0.46 mW, the algae value due to the load difference is -1.98 mW, and the sum of the algae value due to the phase difference and the algae value due to the load difference is -2.4 mW. In addition, the load of the distribution line (D / L) ff is -1.4 mW when connected to the distribution line of the substation A and the substation B.

Therefore, the loop state determination unit 170 determines the loop state from the value obtained by adding the sum of the algae value due to the phase difference and the algae value due to the load difference and the load of the distribution line (D / L) ff in the substation B. At this time, the sum of the algae value by the algae value and the load difference is -2.4mW, the value of the load of the distribution line (D / L) cc plus -1.4mW is -3.8mW, and the absolute value of -3.8mW is the threshold value 14x0. 9 = 12.6 mW, it is judged that the loop is possible.

6 is a flowchart showing an operational flow for a loop current measurement method of a distribution automation system according to the present invention.

As shown in FIG. 6, the loop current measuring apparatus includes a main transformer voltage, phase, load, and impedance at both ends of a normally open-ended switch that connects different distribution lines to each other when connected to different distribution lines, The load and the impedance of the distribution line are inputted (S100).

At this time, the loop current measuring device calculates the algae values at both ends of the normally open-circuit breaker by the phase difference using the main transformer voltage, phase, impedance, and impedance for the power line at both ends of the normally open- (S110).

The loop current measuring device also calculates the algebraic values at both ends of the normally open-circuit breaker by the load difference using the main transformer voltage, impedance, load across the normally open-circuit breaker, and the impedance to the distribution line across the open- (S120).

Thereafter, the loop current measuring apparatus calculates the sum of the algebraic value based on the phase difference calculated in the step S110 and the algebraic value based on the load difference calculated in the step S120 (S130) The loop current at both ends of the normally-open-point switch, that is, the power value due to the loop current, is calculated using the sum of the algebraic values and the loads at both ends of the distribution line (S140).

In this case, if the loop currents at both ends of the switch are less than the threshold values (S150 and S160), the loop current measuring device determines that both ends of the normally open switch are loopable (S170) .

On the other hand, when any one of the loop currents at both ends of the switch is equal to or greater than the threshold value (S150, S160), the loop current measuring device determines that the both ends of the normally open switch are not loopable (S180) S190).

Although the apparatus and method for measuring the loop current of the distribution automation system according to the present invention have been described with reference to the drawings, the present invention is not limited to the embodiments and drawings disclosed herein, Can be applied within the range.

110: input unit 120: output unit
130: control unit 140:
150: alga calculation unit 160: loop current calculation unit
170: Loop state determination unit

Claims (16)

A loop current measuring apparatus for a distribution automation system for measuring a loop current at both ends of an always-open point switch in accordance with an operation of an always-open point switch when a distribution automation system is connected to different distribution lines,
An input unit for receiving measured values from the respective power distribution lines at both ends of the normally open point switch in accordance with the operation of the normally open point switch when connecting to the different power distribution lines;
An algae calculation unit for calculating algae at both ends of the normally open point switch using the measured value input through the input unit;
A loop current calculation unit for calculating a power value due to a loop current formed at both ends of the normally open point switch when connecting the different distribution lines in the distribution automation system using the current value calculated by the current calculation unit; And
And a loop state determiner for comparing the power value of the loop current calculated by the loop current calculator with a threshold value to determine a loop state from the resultant value, Device. The method according to claim 1,
Wherein the measured value is a value
A loop current measurement of a distribution automation system comprising a main transformer primary voltage, a phase, a load and an impedance, a main transformer secondary voltage, a phase, a load, an impedance and an impedance on the distribution line, Device. The method according to claim 1,
Wherein the alga calculation unit calculates algae values based on the phase difference between both ends of the normally open point switch and alga values based on the load difference across the normally open point switch. The method of claim 3,
Wherein the loop current calculator comprises:
A value obtained by adding the value of the tidal current due to the phase difference between both ends of the normally open point switch calculated by the tidal current calculation section and the value of the tidal current due to the difference of the load across the normally open point switch, And calculates a power value due to the loop current formed at both ends of the switch. The method according to claim 1,
Wherein the loop current calculator comprises:
And a power value due to the loop current from the main transformer primary distribution line and a power value due to the loop current from the secondary distribution line to the main transformer at both ends of the normally open point switch, . The method of claim 5,
The power value due to the loop current of the main transformer primary distribution line,
Wherein the main current transformer is a value obtained by adding the value of the tidal current due to the phase difference calculated on the primary side of the main transformer and the value of the tidal current due to the load difference and the value of the load on the primary side power line of the main transformer. . The method of claim 5,
The power value due to the loop current of the secondary side power distribution line,
Wherein the main current transformer is a value obtained by adding a value of a bird by a phase difference calculated by a secondary side of the main transformer and a value of a bird by a load difference and a load value on a secondary side power line of the main transformer. . The method according to claim 1,
An output for outputting at least one of a value input through the input unit, a tidal value calculated from a value input through the input unit, a power value by a loop current calculated from the tidal value, Wherein the loop current measuring device further comprises: A loop current measurement method of a distribution automation system for measuring loop currents at both ends of an always-open-point switch in accordance with operation of an always-open-point switch in a distribution automation system when connecting to different distribution lines,
Receiving a measured value at each of the power distribution lines at both ends of the normally open point switch in accordance with an operation of the normally open point switch when connecting to the different power distribution lines;
Calculating algae at both ends of the normally open-point switch using the measured values;
Calculating power values due to the loop currents formed at both ends of the normally open point switch when connecting the different distribution lines in the distribution automation system using the calculated algae value in the step of calculating the algae; And
Comparing the power value by the loop current calculated in the step of calculating the power value by the loop current with a threshold value and determining a loop state from the resultant value, Current measurement method. The method of claim 9,
Wherein the measured value is a value
A loop current measurement of a distribution automation system comprising a main transformer primary voltage, a phase, a load and an impedance, a main transformer secondary voltage, a phase, a load, an impedance and an impedance on the distribution line, Way. The method of claim 9,
Wherein the step of calculating the algae comprises:
Wherein the current value is calculated based on a phase difference between both ends of the normally open point switch and a current value due to a load difference across the normally open point switch. The method of claim 11,
Wherein the step of calculating the power value by the loop current comprises:
A value obtained by adding the value of the tidal current due to the phase difference at both ends of the normally open point switch and the value of the tidal value due to the load difference at both ends of the normally open point switch, calculated in the step of calculating the tidal current, And calculating a power value by a loop current formed at both ends of the point switch. The method of claim 9,
Wherein the step of calculating the loop current comprises:
And the power value due to the loop current from the main transformer primary distribution line and the power value due to the loop current from the secondary distribution line to the main transformer at both ends of the normally open point switch are respectively calculated . 14. The method of claim 13,
The power value due to the loop current of the main transformer primary distribution line,
Wherein the main current transformer is a value obtained by adding a value of a current due to a phase difference calculated by the main transformer on the primary side and a value of a current due to the load difference and a load value on the primary side power line of the main transformer . 14. The method of claim 13,
The power value due to the loop current of the secondary side power distribution line,
Wherein the main current transformer is a value obtained by adding the value of the tidal current due to the phase difference calculated at the secondary side of the main transformer and the value of the tidal current due to the load difference and the value of the load on the secondary side power line of the main transformer . The method of claim 9,
And outputting at least one of a tidal value calculated from the measured value, a power value based on the loop current calculated from the tidal value, and loop status information to the power distribution line. Of loop current measurement.

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