KR20230069601A - Voltage sensitivity measurement method and measurement device using distributed controller measurement value - Google Patents

Abstract

An embodiment of the present invention provides a method for measuring a voltage sensitivity at a point on a busbar respectively connecting a plurality of power devices to a plurality of points, comprising: a step of acquiring effective power measurement values and ineffective power measurement values for N units of measuring points (N is a natural number of 2 or higher) among the plurality of points; a step of acquiring a voltage measurement value and a power phase angle measurement value of the point; a step of calculating a voltage estimated value of the point by using the sum of a first parameter for each measurement point multiplied by the effective power measurement value of each measurement point (a first sum), the sum of a second parameter for each measurement point multiplied by the ineffective power measurement value of each measurement point (a second sum), and the sum of a third parameter of each measurement point multiplied by the power phase angle of the point; a step of adjusting the first parameter, the second parameter, and the third parameter to minimize the voltage measurement value and the voltage estimated value for the point; and a step of determining the effective power sensitivity for each measurement point in accordance with the first parameter and determining the ineffective power sensitivity in accordance with the second parameter. Therefore, voltage sensitivity can be relatively precisely calculated.

Description

Voltage sensitivity measurement method and measurement device using distributed controller measurement value

This embodiment relates to a technique for measuring voltage sensitivity. More specifically, the present embodiment relates to a technique for measuring voltage sensitivity using only power measurement values for some points.

In a bus line in which a plurality of power devices are connected to a plurality of points, a change in voltage at a specific point relative to a change in power at each point can be understood as a voltage sensitivity at a specific point.

As unstable power devices such as renewable energy sources increase, measuring voltage sensitivity becomes more important. For example, when a voltage problem occurs at a specific point, the voltage problem at the specific point can be quickly alleviated by adjusting the output starting from the power device at the point with the highest voltage sensitivity. For this, accurate measurement of voltage sensitivity is required.

In previous studies, several methods for measuring such voltage sensitivity have been proposed.

One method is to use the Jacobian matrix of Newton-Raphson. This method can calculate the voltage sensitivity very accurately, but all grid information for all points - for example, power , voltage, phase angle, line, topology, etc.

The Perturb & Observe current calculation-based estimation method can calculate the voltage sensitivity relatively accurately and can calculate the voltage sensitivity without special calculation, but has a problem in that it is difficult to calculate the voltage sensitivity related to active power.

In the estimation method through radial distribution network circuit analysis, if all line information is known, voltage sensitivity can be calculated only with information of a specific point, but there is a problem in that impedance information of all lines must be accurately known.

In this way, in the method according to the conventional research, voltage sensitivity can be accurately calculated only when there is information on all points, but there is a problem in that it is difficult to use this method in a situation where distributed controllers are not disposed at all points.

Against this background, an object of the present embodiment is, in one aspect, to provide a technique for relatively accurately calculating voltage sensitivity. In another aspect, an object of the present embodiment is to provide a technique for measuring voltage sensitivity using only power measurement values for some points.

In order to achieve the above object, an embodiment is a method for measuring the voltage sensitivity of a point in a bus line to which a plurality of power devices are connected to a plurality of points, respectively, N (N is a natural number greater than or equal to 2) obtaining active power measurement values and reactive power measurement values for the number of measurement points; obtaining a voltage measurement value and a power phase angle measurement value of the one point; The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) Calculating an estimated voltage value for the one point using a sum (third sum) of products of a third parameter for each measurement point and a power phase angle of the one point; adjusting the first parameter, the second parameter, and the third parameter such that a difference between the measured voltage value and the estimated voltage value for the one point is minimized; and determining active power sensitivity according to the first parameter and reactive power sensitivity according to the second parameter for each measurement point.

The measuring method further includes obtaining a measured value of the incoming short-circuit voltage of one power device connected to the one point, and in the step of calculating the estimated voltage, the measured value of the short-lead voltage at the one point, the first The voltage estimation value for the one point may be calculated by summing the sum, the second sum, and the third sum.

The measuring method sets a data set including the measured values of active power, the measured values of reactive power, the measured voltage, the measured power phase angle, and the measured incoming short-circuit voltage to M (M is a natural number of 2 or greater). Acquisition at different points in time, and adjusting the first parameter, the second parameter, and the third parameter for the M data sets may be performed.

Another embodiment is a method for measuring the voltage sensitivity of a point in a bus line to which a plurality of power devices are connected to a plurality of points, wherein N (N is a natural number equal to or greater than 2) measurement points among the plurality of points. obtaining active power measurement values, reactive power measurement values, and power phase angle measurement values for the s; obtaining a voltage measurement value of the one point; The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) Calculating an estimated voltage value for one point using a sum (third sum) of products of a third parameter for each measurement point and a power phase angle of each measurement point; adjusting the first parameter, the second parameter, and the third parameter such that a difference between the measured voltage value and the estimated voltage value for the one point is minimized; and determining active power sensitivity according to the first parameter and reactive power sensitivity according to the second parameter for each measurement point.

The measuring method further includes obtaining a measured value of the incoming short-circuit voltage of one power device connected to the one point, and in the step of calculating the estimated voltage, the measured value of the short-lead voltage at the one point, the first The voltage estimation value for the one point may be calculated by summing the sum, the second sum, and the third sum.

Another embodiment is a method for measuring the voltage sensitivity of a point in a bus line to which a plurality of power devices are connected to a plurality of points, wherein N (N is a natural number equal to or greater than 2) of the plurality of points is measured. acquiring real power measurement values, reactive power measurement values, power phase angle measurement values, voltage measurement values, and incoming short-circuit voltage measurement values for the points; obtaining a voltage measurement value of the one point; The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) 2), the sum of the products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum), and the sum of the differences between the voltage measurement value and the lead-end voltage measurement value at each measurement point (fourth sum). Calculating an estimated voltage value for the one point using a sum); adjusting the first parameter, the second parameter, and the third parameter such that a difference between the measured voltage value and the estimated voltage value for the one point is minimized; and determining active power sensitivity according to the first parameter and reactive power sensitivity according to the second parameter for each measurement point.

The measuring method further includes obtaining a measured value of the incoming short-circuit voltage of one power device connected to the one point, and in the step of calculating the estimated voltage, the measured value of the short-lead voltage at the one point, the first The voltage estimation value for the one point may be calculated by summing the sum, the second sum, the third sum, and the fourth sum.

In the measuring method, in the step of adjusting the first parameter, the second parameter, and the third parameter, the first parameter, the second parameter, and the third parameter are determined using a least square method. can be adjusted

Another embodiment is an apparatus for measuring the voltage sensitivity of a point in a bus line to which a plurality of power devices are connected to a plurality of points, wherein N (N is a natural number equal to or greater than 2) of the plurality of points is measured. A communication circuit that communicates with the distributed controllers interlocked with the branches; a data acquisition circuit that obtains the voltage measurement value and the power phase angle measurement value of the one point and obtains the active power measurement value and the reactive power measurement value of each measurement point from the distributed controllers; And the sum of the products of the first parameter for each measurement point and the active power measurement value of each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the reactive power measurement value of each measurement point ( second sum) and the sum (third sum) of the products of the third parameter for each measurement point and the power phase angle of the one point to calculate the estimated voltage value for the one point, The first parameter, the second parameter, and the third parameter are adjusted so that the difference between the voltage measurement value and the voltage estimation value is minimized, active power sensitivity is determined for each measurement point according to the first parameter, and the A voltage sensitivity measuring device including a calculation circuit for determining reactive power sensitivity according to two parameters is provided.

The data acquisition circuit acquires the measured value of the incoming short-circuit voltage of one power device connected to the one point, and the calculation circuit acquires the measured value of the short-circuit voltage drawn at the one point, the first sum, the second sum, and the third The voltage estimation value for the one point can be calculated by summing the three sums.

The data acquisition circuit converts a data set including the measured values of the active power, the measured values of the reactive power, the measured voltage, the measured power phase angle, and the measured incoming short-circuit voltage to M (M is a natural number greater than or equal to 2). ) different time points, and the calculating circuit may adjust the first parameter, the second parameter, and the third parameter for the M data sets.

The calculation circuit may adjust the first parameter, the second parameter, and the third parameter using a least square method.

Another embodiment is a device for measuring the voltage sensitivity of a point in a bus line in which a plurality of power devices are connected to a plurality of points, respectively,

a communication circuit communicating with distributed controllers interlocked with N (N is a natural number equal to or greater than 2) measurement points among the plurality of points; a data acquisition circuit for acquiring the measured voltage at the one point and acquiring measured values of active power, measured reactive power, and measured power phase angle at each measuring point from the distributed controllers; And the sum of the products of the first parameter for each measurement point and the active power measurement value of each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the reactive power measurement value of each measurement point ( second sum) and the sum (third sum) of the products of the third parameter for each measurement point and the power phase angle of each measurement point to calculate the estimated voltage value for the one point, The first parameter, the second parameter, and the third parameter are adjusted so that the difference between the voltage measurement value and the voltage estimation value is minimized, active power sensitivity is determined for each measurement point according to the first parameter, and the A voltage sensitivity measuring device including a calculation circuit for determining reactive power sensitivity according to two parameters is provided.

The data acquisition circuit acquires the measured value of the incoming short-circuit voltage of one power device connected to the one point, and the calculation circuit acquires the measured value of the short-circuit voltage drawn at the one point, the first sum, the second sum, and the third The voltage estimation value for the one point can be calculated by summing the three sums.

Another embodiment is an apparatus for measuring the voltage sensitivity of a point in a bus line to which a plurality of power devices are connected to a plurality of points, wherein N (N is a natural number equal to or greater than 2) of the plurality of points is measured. A communication circuit that communicates with the distributed controllers interlocked with the branches; A data acquisition circuit for acquiring the voltage measurement value at the one point and acquiring the active power measurement value, reactive power measurement value, power phase angle measurement value, voltage measurement value, and incoming short-circuit voltage measurement value of each measurement point from the distributed controllers. ; And the sum of the products of the first parameter for each measurement point and the active power measurement value of each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the reactive power measurement value of each measurement point ( 2nd sum), the sum of the products of the third parameter for each measurement point and the power phase angle of each measurement point (3rd sum), and the sum of the differences between the voltage measurement value and the incoming terminal voltage measurement value at each measurement point (the 3rd sum) 4) to calculate the voltage estimate value for the one point, and to minimize the difference between the voltage measurement value and the voltage estimate value for the one point, the first parameter, the second parameter, and the third parameter It provides a voltage sensitivity measuring device comprising a calculation circuit that adjusts, determines the active power sensitivity according to the first parameter for each measurement point, and determines the reactive power sensitivity according to the second parameter.

As described above, according to the present embodiment, voltage sensitivity can be calculated relatively accurately, and voltage sensitivity can be measured using only power measurement values for some points.

1 is a configuration diagram of a voltage sensitivity measurement system according to a first embodiment.
2 is a configuration diagram of a voltage sensitivity measuring device according to a first embodiment.
3 is a flowchart of a method for measuring voltage sensitivity according to the first embodiment.
4 is a configuration diagram of a voltage sensitivity measurement system according to a second embodiment.
5 is a configuration diagram of a voltage sensitivity measuring device according to a second embodiment.
6 is a flowchart of a method for measuring voltage sensitivity according to a second embodiment.
7 is a configuration diagram of a voltage sensitivity measurement system according to a third embodiment.
8 is a configuration diagram of a voltage sensitivity measuring device according to a third embodiment.
9 is a flowchart of a method for measuring voltage sensitivity according to a third embodiment.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description will be omitted.

Also, terms such as first, second, A, B, (a), and (b) may be used in describing the components of the present invention. These terms are only used to distinguish the component from other components, and the nature, order, or order of the corresponding component is not limited by the term. When an element is described as being “connected,” “coupled to,” or “connected” to another element, that element is directly connected or connectable to the other element, but there is another element between the elements. It will be understood that elements may be “connected”, “coupled” or “connected”.

1 is a configuration diagram of a voltage sensitivity measurement system according to a first embodiment.

Referring to FIG. 1 , the voltage sensitivity measuring system 100 may include a plurality of power devices 120a to 120m connected to a bus 130 . The plurality of power devices 120a to 120m may be connected to the bus 130 through different points N1 to Nm, respectively.

The voltage sensitivity measuring system 100 may include a voltage sensitivity measuring device (hereinafter referred to as a 'measuring device', 110) for measuring the voltage sensitivity of a point.

Some 120j of the plurality of power devices 120a to 120m may transmit power data to the measuring device 110 and receive control signals from the measuring device 110 as distributed controllers. Alternatively, a separate meter capable of generating power data and transmitting it to the measurement device 110 may be disposed at some points Nj.

Points at which power data can be transmitted to the measuring device 110 may be referred to as measurement points.

The measuring device 110 may receive power data from the measuring points Nj. The power data may include, for example, a measured active power value (Pj), a measured reactive power value (Qj), a measured power phase angle value, and a power device ( 120j), and may include the voltage measurement value at the corresponding point.

Among the plurality of points N1 to Nm to which the plurality of power devices 120a to 120m are connected, points other than the measurement points Nj may be referred to as non-measurement points Ni.

The measuring device 110 may not be able to obtain power data from non-measurement points Ni. The measuring device 110 may not receive all of the aforementioned types of power data from the non-measurement points Ni, and receives some measurement values - for example, active power measurement values, reactive power measurement values, etc. may not be able to

In the conventional voltage sensitivity measurement method, when non-measurement points Ni are included in the plurality of points 120a to 120m, the voltage sensitivity cannot be accurately calculated. In contrast, the measuring device according to the present embodiment can relatively accurately calculate voltage sensitivity even when non-measurement points Ni are included.

The measuring device 110 may calculate voltage sensitivity according to a data-driven method.

[Equation 1]

는 측정하려는 일 지점의 전압측정값이고,

는 일 지점의 인입단전압측정값이고,

는 각 지점의 유효전력민감도이고,

는 각 지점의 유효전력값이고,

는 각 지점의 무효전력민감도이고,

는 각 지점의 무효전력값이다.In Equation 1,

is the voltage measurement value at a point to be measured,

is the measured value of the incoming short-circuit voltage at a point,

is the active power sensitivity of each point,

is the active power value at each point,

is the reactive power sensitivity of each point,

is the reactive power value at each point.

Some of the plurality of points may not have a power value measured. If the equation is separated into a point where the power value is measured and a point where the power value is not measured, the latter part of Equation 1 is obtained.

는 유효전력값이 측정되는 지점에서의 유효전력민감도와 유효전력측정값의 곱을 나타내고,

는 무효전력값이 측정되는 지점에서의 무효전력민감도와 무효전력측정값의 곱을 나타낸다.here,

Represents the product of the active power sensitivity and the measured active power value at the point where the active power value is measured,

Represents the product of the reactive power sensitivity and the measured reactive power value at the point where the reactive power value is measured.

는 유효전력값이 측정되지 않는 지점에서의 유효전력민감도와 유효전력값(실제로는 획득되지 않는 값)의 곱을 나타내고,

는 무효전력값이 측정되지 않는 지점에서의 무효전력민감도와 무효전력값(실제로는 획득되지 않는 값)의 곱을 나타낸다.and,

Represents the product of the active power sensitivity and the active power value (a value that is not actually obtained) at a point where the active power value is not measured,

Represents the product of the reactive power sensitivity at the point where the reactive power value is not measured and the reactive power value (a value that is not actually obtained).

In this data-driven method, since unmeasured power values are included, voltage sensitivity for each point cannot be accurately calculated.

The measuring device 110 according to the first embodiment solves the above-described problem by replacing the equation for the point where the active power value and the reactive power value are not measured using a power phase angle measurement value at one point with another equation, there is.

[Equation 2]

는 측정지점에서의 유효전력측정값이고,

는 그에 대응되는 파라미터(계수)이고,

는 측정지점에서의 무효전력측정값이고,

는 그에 대응되는 파라미터(계수)이고,

는 비측정지점에서의 유효전력값이고,

는 그에 대응되는 파라미터(계수)이고,

는 비측정지점에서의 무효전력값이고,

는 그에 대응되는 파라미터(계수)이다.First, the voltage measurement value at one point can be expressed as Equation 2. here,

is the measured value of active power at the measuring point,

is the corresponding parameter (coefficient),

is the reactive power measured value at the measuring point,

is the corresponding parameter (coefficient),

is the active power value at the non-measurement point,

is the corresponding parameter (coefficient),

is the reactive power value at the non-measurement point,

is a parameter (coefficient) corresponding thereto.

[Equation 3]

Equation 4]

By rearranging Equation 2, it can become a determinant such as Equation 3 and Equation 4.

[Equation 5]

은 수학식 5와 같이 측정지점에서의 유효전력측정값

및 무효전력측정값

, 그리고, 비측정지점에서의 유효전력값

및 무효전력값

으로 나타내질 수 있다.On the other hand, the power phase angle measurement value at one point

is the active power measurement value at the measurement point as shown in Equation 5

and reactive power measurement value

, and, the active power value at the non-measurement point

and reactive power value

can be represented as

In Equation 5, coefficients may be attached to the active/reactive power (measured) values.

[Equation 6]

By rearranging Equation 5, it can be a determinant like Equation 6.

[Equation 7]

[Equation 8]

및 무효전력값

으로 정리하면 수학식 8이 된다.Equation 6, the active power value for the non-measurement point

and reactive power value

Summarizing to , it becomes Equation 8.

Then, when Equation 8 is substituted into Equation 4, Equation 9 below can be obtained.

[Equation 9]

의 계수인

를 제1파라미터라고 하고, 무효전력값

의 계수인

를 제2파라미터라고 하고, 전력위상각측정값

의 계수인

를 제3파라미터라고 할 수 있다.In Equation 9, the active power value

coefficient of

is called the first parameter, and the reactive power value

coefficient of

is called the second parameter, and the power phase angle measurement value

coefficient of

may be referred to as the third parameter.

, 각 측정지점에 대한 제2파라미터와 각 측정지점의 무효전력측정값의 곱들의 합(제2합)

, 그리고, 각 측정지점에 대한 제3파라미터와 일 지점의 전력위상각측정값의 곱들의 합(제3합)

을 이용하여 일 지점에 대한 전압추정값을 계산할 수 있다.The measuring device 110 is the sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum).

, the sum of the products of the second parameter for each measurement point and the measured value of reactive power at each measurement point (second sum)

, And, the sum of the products of the third parameter for each measurement point and the power phase angle measurement value at one point (third sum)

A voltage estimation value for a point can be calculated using

In addition, the measuring device 110 may adjust the first parameter, the second parameter, and the third parameter so that a difference between the measured voltage value and the estimated voltage value for one point is minimized.

In addition, the measuring device 110 may determine the active power sensitivity of each measurement point according to the first parameter, and determine the reactive power sensitivity of each measurement point according to the second parameter. For example, the measurement device 110 may determine the first parameter as the active power sensitivity of each measurement point, and determine the second parameter as the reactive power sensitivity of each measurement point.

2 is a configuration diagram of a voltage sensitivity measuring device according to a first embodiment.

Referring to FIG. 2 , the measurement device 110 may include a communication circuit 210 , a data acquisition circuit 220 and a calculation circuit 230 .

The communication circuit 210 may communicate with distributed controllers interlocked with N (N is a natural number equal to or greater than 2) measurement points among a plurality of points. Also, the communication circuit 210 may receive power data of measurement points from the distributed controllers. The power data may include a measured value of active power, a measured value of reactive power, a measured voltage value, a measured value of incoming terminal voltage, and a measured value of power phase angle.

The data acquisition circuit 220 may obtain a voltage measurement value and a power phase angle measurement value of one point for which voltage sensitivity is to be calculated, and may obtain active power measurement values and reactive power measurement values of each measurement point from distributed controllers.

The data acquisition circuit 220 acquires a voltage measurement value, an incoming terminal voltage measurement value, a power phase angle measurement value, an active power measurement value, and a reactive power measurement value at a point using its own measurement circuit, or Through communication—communication can be performed by the communication circuit 210—it is possible to obtain a voltage measurement value at a point, an incoming short voltage measurement value, a power phase angle measurement value, an active power measurement value, a reactive power measurement value, and the like. there is.

The data acquisition circuit 220 may acquire M (M is a natural number greater than or equal to 2) data sets at different times.

The data set may include values necessary for calculating the voltage sensitivity of the calculation circuit 230. For example, the data set includes a voltage measurement value for each measurement point and one point, an incoming terminal voltage measurement value, and a power phase angle measurement. value, active power measurement value, and reactive power measurement value.

The calculation circuit 230 is the sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the second parameter for each measurement point and the measured reactive power value at each measurement point. A voltage estimation value for one point is calculated using the sum of products of (second sum) and the sum of products of the third parameter for each measurement point and the power phase angle of one point (third sum), and at one point The first parameter, the second parameter, and the third parameter are adjusted to minimize the difference between the voltage measurement value and the voltage estimation value for each measurement point. Active power sensitivity is determined according to the first parameter and invalid according to the second parameter It can be determined by power sensitivity.

The calculation circuit 230 may calculate an estimated voltage value for a point by adding the measured value of the incoming terminal voltage at the point, the first sum, the second sum, and the third sum.

When the data acquisition circuit 220 acquires M data sets, the calculation circuit 230 determines the first parameter, the second parameter, and the third parameter so that the difference between the voltage measurement value and the voltage estimation value for the M data sets is minimized. can be adjusted.

The calculation circuit 230 may adjust the first parameter, the second parameter, and the third parameter using a least square method, for example, voltage measurements and voltages calculated for M data sets. The first parameter, the second parameter, and the third parameter may be adjusted so that the sum of the squared differences of the estimated values is minimized.

3 is a flowchart of a method for measuring voltage sensitivity according to the first embodiment.

Referring to FIG. 3 , the measuring device may acquire measured values of real power and measured values of reactive power for N (N is a natural number equal to or greater than 2) measurement points among a plurality of points (S300).

Then, the measurement device may obtain a voltage measurement value and a power phase angle measurement value at one point (S302).

The measurement device may further obtain a measurement value of the incoming short-circuit voltage of one power device connected to one point.

And, the measuring device is the sum of the products of the first parameter for each measurement point and the measured value of active power at each measurement point (first sum), the second parameter for each measurement point and the measured value of reactive power at each measurement point. A voltage estimation value for one point may be calculated using the sum of products (second sum) and the sum of products of the third parameter for each measurement point and the power phase angle of one point (third sum) (S304).

The measuring device may calculate an estimated voltage value for one point by adding the first sum, second sum, and third sum of the incoming terminal voltage measurement value at one point.

Then, the measuring device may adjust the first parameter, the second parameter, and the third parameter so that the difference between the measured voltage value and the estimated voltage value for one point is minimized (S306).

The measurement device acquires a data set including active power measurement values, reactive power measurement values, voltage measurement values, power phase angle measurement values, and incoming short-circuit voltage measurement values at M (M is a natural number equal to or greater than 2) different points in time. and adjust the first parameter, the second parameter, and the third parameter for M datasets.

Then, the measuring device may determine the active power sensitivity according to the first parameter and the reactive power sensitivity according to the second parameter for each measurement point (S308).

4 is a configuration diagram of a voltage sensitivity measurement system according to a second embodiment.

Referring to FIG. 4 , the voltage sensitivity measurement system 400 may include a plurality of power devices 420a to 420m connected to a bus 430 . The plurality of power devices 420a to 420m may be connected to the bus 430 through different points N1 to Nm, respectively.

The voltage sensitivity measuring system 400 may include a voltage sensitivity measuring device (hereinafter referred to as a 'measuring device', 410) for measuring the voltage sensitivity of a point.

Some 420j of the plurality of power devices 420a to 420m may transmit power data to the measuring device 410 and receive control signals from the measuring device 410 as distributed controllers. Alternatively, a separate meter capable of generating power data and transmitting it to the measuring device 410 may be disposed at some points Nj.

Points at which power data can be transmitted to the measuring device 410 may be referred to as measurement points.

The measuring device 410 may receive power data from the measuring points Nj. The power data may include, for example, a measured active power value (Pj), a measured reactive power value (Qj), and a measured power phase angle value (θj) at a corresponding point, It may include the measurement value of the incoming terminal voltage of the power device 420j, and may include the measurement value of the voltage at the corresponding point.

Among the plurality of points N1 to Nm to which the plurality of power devices 420a to 420m are connected, points other than the measurement points Nj may be referred to as non-measurement points Ni.

The measuring device 410 may not be able to obtain power data from non-measurement points Ni. The measuring device 410 may not be able to receive all of the aforementioned types of power data from the non-measurement points Ni, and receives some measured values - for example, active power measured values, reactive power measured values, etc. may not be able to

In the conventional voltage sensitivity measurement method, when non-measurement points Ni are included in the plurality of points 420a to 420m, the voltage sensitivity cannot be accurately calculated. In contrast, the measuring device according to the present embodiment can relatively accurately calculate voltage sensitivity even when non-measurement points Ni are included.

The measurement device 410 according to the second embodiment may replace the equation for the point where the active power value and the reactive power value are not measured with another formula using the power phase angle measurement values of the measurement points.

[Equation 10]

(벡터)을 측정지점에서의 유효전력측정값 및 무효전력측정값, 그리고, 비측정지점에서의 유효전력값 및 무효전력값으로 나타낸 식이다.Equation 10 is the power phase angle measurement values of the measurement points

It is an equation expressing (vector) as active power measurement value and reactive power measurement value at the measurement point, and active power value and reactive power value at the non-measurement point.

[Equation 11]

Equation 11 can be obtained by arranging Equation 10 with the active power value and the reactive power value for the non-measurement point, and Equation 12 can be obtained by substituting this into Equation 4.

[Equation 12]

의 계수인

를 제1파라미터라고 하고, 무효전력값

의 계수인

를 제2파라미터라고 하고, 전력위상각측정값

의 계수인

를 제3파라미터라고 할 수 있다.Active power value in Equation 12

coefficient of

is called the first parameter, and the reactive power value

coefficient of

is called the second parameter, and the power phase angle measurement value

coefficient of

may be referred to as the third parameter.

The measuring device 410 is the sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the second parameter for each measurement point and the measured reactive power value at each measurement point. An estimated voltage value for one point can be calculated using the sum of products of (second sum) and the sum of products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum).

Then, the measuring device 410 may adjust the first parameter, the second parameter, and the third parameter so that the difference between the measured voltage value and the estimated voltage value for one point is minimized.

In addition, the measuring device 410 may determine the active power sensitivity of each measurement point according to the first parameter, and determine the reactive power sensitivity of each measurement point according to the second parameter. For example, the measuring device 410 may determine the first parameter as the active power sensitivity of each measurement point, and determine the second parameter as the reactive power sensitivity of each measurement point.

5 is a configuration diagram of a voltage sensitivity measuring device according to a second embodiment.

Referring to FIG. 5 , the measurement device 410 may include a communication circuit 510 , a data acquisition circuit 520 and a calculation circuit 530 .

The communication circuit 510 may communicate with distributed controllers interlocked with N (N is a natural number equal to or greater than 2) measurement points among a plurality of points. Also, the communication circuit 510 may receive power data of measurement points from the distributed controllers. The power data may include a measured value of active power, a measured value of reactive power, a measured voltage value, a measured value of incoming terminal voltage, and a measured value of power phase angle.

The data acquisition circuit 520 may obtain a voltage measurement value at one point, and may obtain an active power measurement value, a reactive power measurement value, and a power phase angle measurement value of each measurement point from distributed controllers.

The data acquisition circuit 520 acquires a voltage measurement value, a lead-end voltage measurement value, a power phase angle measurement value, an active power measurement value, a reactive power measurement value, etc. at a point using its own measurement circuit, or Through communication—communication can be performed by the communication circuit 510—it is possible to obtain a voltage measurement value at a point, an incoming short voltage measurement value, a power phase angle measurement value, an active power measurement value, a reactive power measurement value, and the like. there is.

The data acquisition circuit 520 may acquire M (M is a natural number greater than or equal to 2) data sets at different times.

The data set may include values necessary for calculating the voltage sensitivity of the calculation circuit 530. For example, the data set may include a voltage measurement value for each measurement point and one point, an incoming terminal voltage measurement value, and a power phase angle measurement. value, active power measurement value, and reactive power measurement value.

The calculation circuit 530 is the sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the second parameter for each measurement point and the measured reactive power value at each measurement point. A voltage estimation value for one point is calculated using the sum of products of (second sum) and the sum of products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum), and The first parameter, the second parameter, and the third parameter are adjusted so that the difference between the voltage measurement value and the voltage estimation value for It can be determined by the reactive power sensitivity.

The calculation circuit 530 may calculate an estimated voltage value for a point by adding the measured value of the incoming terminal voltage at the point, the first sum, the second sum, and the third sum.

When the data acquisition circuit 520 acquires M data sets, the calculation circuit 530 determines the first parameter, the second parameter, and the third parameter so that the difference between the voltage measurement value and the voltage estimation value for the M data sets is minimized. can be adjusted.

The calculation circuit 530 may adjust the first parameter, the second parameter, and the third parameter using a least square method, for example, voltage measurements and voltages calculated for M data sets. The first parameter, the second parameter, and the third parameter may be adjusted so that the sum of the squared differences of the estimated values is minimized.

6 is a flowchart of a method for measuring voltage sensitivity according to a second embodiment.

Referring to FIG. 6 , the measuring device may obtain real power measurement values, reactive power measurement values, and power phase angle measurement values for N (N is a natural number equal to or greater than 2) measurement points among a plurality of points. (S600).

And, the measuring device may acquire a voltage measurement value at one point (S602).

The measurement device may further obtain a measurement value of the incoming short-circuit voltage of one power device connected to one point.

And, the measuring device is the sum of the products of the first parameter for each measurement point and the measured value of active power at each measurement point (first sum), the second parameter for each measurement point and the measured value of reactive power at each measurement point. A voltage estimation value for one point can be calculated using the sum of products (second sum) and the sum of products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum) (S604). .

The measuring device may calculate an estimated voltage value for one point by adding the first sum, second sum, and third sum of the incoming terminal voltage measurement value at one point.

Then, the measuring device may adjust the first parameter, the second parameter, and the third parameter so that the difference between the measured voltage value and the estimated voltage value for one point is minimized (S606).

The measurement device acquires a data set including active power measurement values, reactive power measurement values, voltage measurement values, power phase angle measurement values, and incoming short-circuit voltage measurement values at M (M is a natural number equal to or greater than 2) different points in time. and adjust the first parameter, the second parameter, and the third parameter for M datasets.

Then, the measuring device may determine the active power sensitivity according to the first parameter and the reactive power sensitivity according to the second parameter for each measurement point (S608).

7 is a configuration diagram of a voltage sensitivity measurement system according to a third embodiment.

Referring to FIG. 7 , the voltage sensitivity measurement system 700 may include a plurality of power devices 720a to 720m connected to a bus 730 . The plurality of power devices 720a to 720m may be connected to the bus 730 through different points N1 to Nm, respectively.

The voltage sensitivity measuring system 700 may include a voltage sensitivity measuring device (hereinafter referred to as a 'measuring device', 710) that measures the voltage sensitivity of a point.

Some 720j of the plurality of power devices 720a to 720m may transmit power data to the measuring device 710 and receive control signals from the measuring device 710 as distributed controllers. Alternatively, a separate meter capable of generating power data and transmitting it to the measuring device 710 may be disposed at some points Nj.

Points at which power data can be transmitted to the measuring device 710 may be referred to as measurement points.

The measuring device 710 may receive power data from the measuring points Nj. The power data may include, for example, a measured active power value (Pj), a measured reactive power value (Qj), and a measured power phase angle value (θj) at a corresponding point, The voltage measurement value (Vs) of the power device 720j may be included, and the voltage measurement value (P) of the corresponding point may be included.

Among the plurality of points N1 to Nm to which the plurality of power devices 720a to 720m are connected, points other than the measurement points Nj may be referred to as non-measurement points Ni.

The measuring device 710 may not be able to obtain power data from non-measurement points Ni. The measuring device 710 may not receive all of the aforementioned types of power data from the non-measurement points Ni, and receives some measured values - for example, active power measured values, reactive power measured values, etc. may not be able to

In the conventional voltage sensitivity measurement method, when non-measurement points Ni are included in the plurality of points 720a to 720m, the voltage sensitivity cannot be accurately calculated. In contrast, the measuring device according to the present embodiment can relatively accurately calculate voltage sensitivity even when non-measurement points Ni are included.

The measuring device 710 according to the third embodiment can replace the equation for the point where the active power value and the reactive power value are not measured with another formula using both the voltage measurement values and the power phase measurement values of the measurement points. there is.

[Equation 13]

[Equation 14]

(벡터)은 수학식 13과 같이 표현될 수 있고, 같은 방식으로 전력위상측정값들을 표현한 후에 합치면 수학식 14를 얻을 수 있다.Voltage measurement values of measurement points

(vector) can be expressed as in Equation 13, and Equation 14 can be obtained by combining the power phase measurement values after expressing them in the same way.

[Equation 15]

Then, Equation 15 can be obtained by substituting Equation 14 into Equation 4 and rearranging.

, 각 측정지점에 대한 제2파라미터와 각 측정지점의 무효전력측정값의 곱들의 합(제2합)

, 각 측정지점에 대한 제3파라미터와 각 측정지점의 전력위상각의 곱들의 합(제3합)

및 각 측정지점의 전압측정값과 인입단전압측정값의 차이들의 합(제4합)

을 이용하여 상기 일 지점에 대한 전압추정값을 계산할 수 있다.The measuring device 710 is the sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum).

, the sum of the products of the second parameter for each measurement point and the measured value of reactive power at each measurement point (second sum)

, the sum of the products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum)

and the sum of the differences between the voltage measurement value at each measurement point and the incoming short-circuit voltage measurement value (4th sum)

A voltage estimation value for the one point can be calculated using

In addition, the measuring device 710 may adjust the first parameter, the second parameter, and the third parameter so that a difference between the measured voltage value and the estimated voltage value for one point is minimized.

Also, the measuring device 710 may determine the active power sensitivity of each measurement point according to the first parameter, and determine the reactive power sensitivity of each measurement point according to the second parameter. For example, the measuring device 710 may determine the first parameter as the active power sensitivity of each measurement point, and determine the second parameter as the reactive power sensitivity of each measurement point.

8 is a configuration diagram of a voltage sensitivity measuring device according to a third embodiment.

Referring to FIG. 8 , a measuring device 710 may include a communication circuit 810 , a data acquisition circuit 820 and a calculation circuit 830 .

The communication circuit 810 may communicate with distributed controllers interlocked with N (N is a natural number equal to or greater than 2) measurement points among a plurality of points. Also, the communication circuit 810 may receive power data of measurement points from the distributed controllers. The power data may include a measured value of active power, a measured value of reactive power, a measured voltage value, a measured value of incoming terminal voltage, and a measured value of power phase angle.

The data acquisition circuit 820 acquires the voltage measurement value at one point and obtains the active power measurement value, the reactive power measurement value, the power phase angle measurement value, the voltage measurement value, and the lead-end voltage measurement value of each measurement point from the distributed controllers. can be obtained

The data acquisition circuit 820 acquires a voltage measurement value, a lead-end voltage measurement value, a power phase angle measurement value, an active power measurement value, a reactive power measurement value, etc. at a point using its own measurement circuit, or Through communication—communication can be performed by the communication circuit 810—it is possible to obtain a voltage measurement value at a point, an incoming short voltage measurement value, a power phase angle measurement value, an active power measurement value, a reactive power measurement value, and the like. there is.

The data acquisition circuit 820 may acquire M (M is a natural number greater than or equal to 2) data sets at different times.

The data set may include values necessary for calculating the voltage sensitivity of the calculation circuit 830. For example, the data set may include a voltage measurement value for each measurement point and one point, an incoming terminal voltage measurement value, and a power phase angle measurement. value, active power measurement value, and reactive power measurement value.

The calculation circuit 830 is the sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the second parameter for each measurement point and the measured reactive power value at each measurement point. The sum of the products of (second sum), the sum of the products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum), and the voltage measurement value of each measurement point and the incoming terminal voltage measurement value Calculate an estimated voltage value for one point using the sum of the differences (fourth sum), adjust the first parameter, second parameter, and third parameter so that the difference between the measured voltage value and the estimated voltage value for one point is minimized, , the active power sensitivity can be determined according to the first parameter for each measurement point, and the reactive power sensitivity can be determined according to the second parameter.

The calculation circuit 830 may calculate an estimated voltage value for a point by adding the first, second, third, and fourth sums of the incoming terminal voltage measurement at the point.

When the data acquisition circuit 820 acquires M data sets, the calculation circuit 830 determines the first parameter, the second parameter, and the third parameter so that the difference between the voltage measurement value and the voltage estimation value for the M data sets is minimized. can be adjusted.

The calculation circuit 830 may adjust the first parameter, the second parameter, and the third parameter using a least square method, for example, voltage measurements and voltages calculated for M data sets. The first parameter, the second parameter, and the third parameter may be adjusted so that the sum of the squared differences of the estimated values is minimized.

9 is a flowchart of a method for measuring voltage sensitivity according to a third embodiment.

Referring to FIG. 9 , the measurement device measures active power measurement values, reactive power measurement values, power phase angle measurement values, and voltage measurement values for N (N is a natural number equal to or greater than 2) measurement points among a plurality of points. s and incoming short voltage measurement values can be obtained (S900).

The measuring device may acquire a voltage measurement value at one point (S902).

The measurement device may further obtain a measurement value of the incoming short-circuit voltage of one power device connected to one point.

The measuring device is the sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the product of the second parameter for each measurement point and the measured reactive power value at each measurement point. Sum (second sum), sum of products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum), and sum of differences between the voltage measurement value at each measurement point and the incoming short-circuit voltage measurement value A voltage estimation value for one point may be calculated using (fourth sum) (S904).

The measuring device may calculate an estimated voltage value for a point by adding the measured value of the incoming terminal voltage at the point, the first sum, the second sum, the third sum, and the fourth sum.

Then, the measuring device may adjust the first parameter, the second parameter, and the third parameter so that the difference between the measured voltage value and the estimated voltage value for one point is minimized (S906).

Then, the measuring device may determine the active power sensitivity according to the first parameter and the reactive power sensitivity according to the second parameter for each measurement point (S908).

As described above, according to the present embodiment, voltage sensitivity can be calculated relatively accurately, and voltage sensitivity can be measured using only power measurement values for some points.

Terms such as "comprise", "comprise" or "having" described above mean that the corresponding component may be inherent unless otherwise stated, and therefore do not exclude other components. It should be construed that it may further include other components. All terms, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs, unless defined otherwise. Commonly used terms, such as terms defined in a dictionary, should be interpreted as consistent with the meaning in the context of the related art, and unless explicitly defined in the present invention, they are not interpreted in an ideal or excessively formal meaning.

Claims (15)

A method for measuring the voltage sensitivity of a point in a bus line in which a plurality of power devices are connected to a plurality of points, respectively,
obtaining active power measurement values and reactive power measurement values for N (N is a natural number equal to or greater than 2) measurement points among the plurality of points;
obtaining a voltage measurement value and a power phase angle measurement value of the one point;
The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) Calculating an estimated voltage value for the one point using a sum (third sum) of products of a third parameter for each measurement point and a power phase angle of the one point;
adjusting the first parameter, the second parameter, and the third parameter such that a difference between the measured voltage value and the estimated voltage value for the one point is minimized; and
Determining active power sensitivity according to the first parameter for each measurement point and determining reactive power sensitivity according to the second parameter
Voltage sensitivity measurement method comprising a. According to claim 1,
Further comprising the step of obtaining a measured value of the incoming short-circuit voltage of one power device connected to the one point,
In the step of calculating the voltage estimation value,
A voltage sensitivity measurement method of calculating an estimated voltage value for the one point by summing the incoming terminal voltage measurement value at the one point, the first sum, the second sum, and the third sum. According to claim 2,
A data set including the measured active power values, the measured reactive power values, the measured voltage value, the measured power phase angle value, and the measured incoming short-circuit voltage value is obtained at M (M is a natural number equal to or greater than 2) at different points in time. obtained from,
The voltage sensitivity measurement method of performing the step of adjusting the first parameter, the second parameter, and the third parameter with respect to the M data sets. A method for measuring the voltage sensitivity of a point in a bus line in which a plurality of power devices are connected to a plurality of points, respectively,
obtaining active power measurement values, reactive power measurement values, and power phase angle measurement values for N (N is a natural number equal to or greater than 2) measurement points among the plurality of points;
obtaining a voltage measurement value of the one point;
The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) Calculating an estimated voltage value for one point using a sum (third sum) of products of a third parameter for each measurement point and a power phase angle of each measurement point;
adjusting the first parameter, the second parameter, and the third parameter such that a difference between the measured voltage value and the estimated voltage value for the one point is minimized; and
Determining active power sensitivity according to the first parameter for each measurement point and determining reactive power sensitivity according to the second parameter
Voltage sensitivity measurement method comprising a. According to claim 4,
Further comprising the step of obtaining a measured value of the incoming short-circuit voltage of one power device connected to the one point,
In the step of calculating the voltage estimation value,
A voltage sensitivity measurement method of calculating an estimated voltage value for the one point by summing the incoming terminal voltage measurement value at the one point, the first sum, the second sum, and the third sum. A method for measuring the voltage sensitivity of a point in a bus line in which a plurality of power devices are connected to a plurality of points, respectively,
Active power measurement values, reactive power measurement values, power phase angle measurement values, voltage measurement values, and incoming short-circuit voltage measurement values for N (N is a natural number equal to or greater than 2) measurement points among the plurality of points are measured. obtaining;
obtaining a voltage measurement value of the one point;
The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) 2), the sum of the products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum), and the sum of the differences between the voltage measurement value and the lead-end voltage measurement value at each measurement point (fourth sum). Calculating an estimated voltage value for the one point using a sum);
adjusting the first parameter, the second parameter, and the third parameter such that a difference between the measured voltage value and the estimated voltage value for the one point is minimized; and
Determining active power sensitivity according to the first parameter for each measurement point and determining reactive power sensitivity according to the second parameter
Voltage sensitivity measurement method comprising a. According to claim 6,
Further comprising the step of obtaining a measured value of the incoming short-circuit voltage of one power device connected to the one point,
In the step of calculating the voltage estimation value,
A method for measuring voltage sensitivity in which an estimated voltage value for the one point is calculated by summing the incoming terminal voltage measurement value at the one point, the first sum, the second sum, the third sum, and the fourth sum. According to claim 6,
In the step of adjusting the first parameter, the second parameter and the third parameter,
A voltage sensitivity measurement method for adjusting the first parameter, the second parameter, and the third parameter using a least square method. In the apparatus for measuring the voltage sensitivity of a point in a bus line to which a plurality of power devices are connected to a plurality of points,
a communication circuit communicating with distributed controllers interlocked with N (N is a natural number equal to or greater than 2) measurement points among the plurality of points;
a data acquisition circuit that obtains the voltage measurement value and the power phase angle measurement value of the one point and obtains the active power measurement value and the reactive power measurement value of each measurement point from the distributed controllers; and
The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) 2 sum) and the sum (third sum) of products of the third parameter for each measurement point and the power phase angle of the one point, the voltage estimate value for the one point is calculated, and the voltage estimate for the one point is calculated. The first parameter, the second parameter, and the third parameter are adjusted so that the difference between the measured value and the voltage estimation value is minimized, active power sensitivity is determined for each measurement point according to the first parameter, and the second parameter is determined. Calculation circuit that determines reactive power sensitivity according to parameters
Voltage sensitivity measuring device comprising a. According to claim 9,
The data acquisition circuit acquires a measured value of the incoming short-circuit voltage of one power device connected to the one point,
Wherein the calculation circuit calculates an estimated voltage value for the one point by summing the incoming terminal voltage measurement value of the one point, the first sum, the second sum, and the third sum. According to claim 10,
The data acquisition circuit converts a data set including the measured values of the active power, the measured values of the reactive power, the measured voltage, the measured power phase angle, and the measured incoming short-circuit voltage to M (where M is a natural number greater than or equal to 2). ) obtained at different time points,
The calculation circuit adjusts the first parameter, the second parameter and the third parameter for the M data sets. According to claim 11,
The voltage sensitivity measuring device wherein the calculation circuit adjusts the first parameter, the second parameter, and the third parameter using a least square method. In the apparatus for measuring the voltage sensitivity of a point in a bus line to which a plurality of power devices are connected to a plurality of points,
a communication circuit communicating with distributed controllers interlocked with N (N is a natural number equal to or greater than 2) measurement points among the plurality of points;
a data acquisition circuit for acquiring the measured voltage at the one point and acquiring measured values of active power, measured reactive power, and measured power phase angle at each measuring point from the distributed controllers; and
The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) 2) and the sum (third sum) of the products of the third parameter for each measurement point and the power phase angle of each measurement point to calculate the estimated voltage value for the one point, and the voltage estimate for the one point The first parameter, the second parameter, and the third parameter are adjusted so that the difference between the measured value and the voltage estimation value is minimized, active power sensitivity is determined for each measurement point according to the first parameter, and the second parameter is determined. Calculation circuit that determines reactive power sensitivity according to parameters
Voltage sensitivity measuring device comprising a. According to claim 13,
The data acquisition circuit acquires a measured value of the incoming short-circuit voltage of one power device connected to the one point,
Wherein the calculation circuit calculates an estimated voltage value for the one point by summing the incoming terminal voltage measurement value of the one point, the first sum, the second sum, and the third sum. In the apparatus for measuring the voltage sensitivity of a point in a bus line to which a plurality of power devices are connected to a plurality of points,
a communication circuit communicating with distributed controllers interlocked with N (N is a natural number equal to or greater than 2) measurement points among the plurality of points;
A data acquisition circuit for acquiring the voltage measurement value at the one point and acquiring the active power measurement value, reactive power measurement value, power phase angle measurement value, voltage measurement value, and incoming short-circuit voltage measurement value of each measurement point from the distributed controllers. ; and
The sum of the products of the first parameter for each measurement point and the measured active power value at each measurement point (first sum), the sum of the products of the second parameter for each measurement point and the measured reactive power value at each measurement point (the second sum) 2), the sum of the products of the third parameter for each measurement point and the power phase angle of each measurement point (third sum), and the sum of the differences between the voltage measurement value and the lead-end voltage measurement value at each measurement point (fourth sum). sum) to calculate the voltage estimation value for the one point, and adjust the first parameter, the second parameter, and the third parameter so that the difference between the voltage measurement value and the voltage estimation value for the one point is minimized. and a calculation circuit for determining the active power sensitivity according to the first parameter for each measurement point and determining the reactive power sensitivity according to the second parameter.
Voltage sensitivity measuring device comprising a.

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