KR101226474B1 - Prediction device deterioration of condenser bank and method rhereof - Google Patents

Abstract

PURPOSE: A degradation estimating device of condenser bank and a method thereof are provided to prevent accident for a series reactor and condenser by predicting the state of the flame and the degradation of the condenser to minimize the spread of failure. CONSTITUTION: A calculating unit(15a) calculates the collected information. A controlling unit(15b) monitors the flame state of the condenser, predicts the increase of the current in the condenser, and the value of the volume of the condenser based on the results of the calculating unit. A controlling unit detects the overloaded degree of the series reactor and the flame state of the condenser using the increasing state of the predicted current in case of malfunction in the condenser. An alarming unit(15c) generates an alarm when the sensing values of the overloaded degree of the series reactor and the state of the flame of the condenser reaches a first predetermined value according to the controlling unit. A power cutoff unit(15d) shuts off the power when the sensing value of the overload degree of the series reactor and flame state of the condenser reaches a second predetermined value. [Reference numerals] (15a) Calculating unit; (15b) Controlling unit; (15c) Alarming unit; (15d) Power cutoff unit; (15e) Display unit

Description

Prediction device deterioration of condenser bank and method rhereof

The present invention relates to an apparatus and method for predicting deterioration of a capacitor bank, and more particularly, to calculate deterioration and deterioration of a capacitor and a series reactor by calculating a change state of the capacity and power consumption of each capacitor and the series reactor of the capacitor bank. The present invention relates to an apparatus and method for predicting deterioration of a capacitor bank capable of predicting and minimizing the spread of failure by utilizing prediction information.

Low-voltage, high-pressure and special high-voltage advanced capacitors are widely used for the purpose of reducing electric charges by reducing power factor, reducing facility capacity, and loss of distribution facilities. As described above, the advance capacitors used in large quantities are being changed to dielectric materials according to the change of times.

In recent years, as harmonic generators such as general-purpose inverters are spreading, harmonic currents leak into the 6600V distribution system, which distorts the voltage of the distribution system, and abnormal noise of capacitors, abnormal noise of series reactors, overheating and burnout in high-voltage advanced capacitor equipment. It is causing trouble. Recently, due to the new renewable energy policy, harmonics are increasing due to the increase in power converters for distributed power supplies, and capacitors used for low voltage or extra high voltage are mostly used at the load end for power factor improvement, which makes it difficult to manage even when defects occur.

Since the problem of harmonic disturbance is controversial and the resonance phenomenon between the capacitor equipment and the distribution system impedance further expands the voltage distortion, it is preferable to install the capacitor in combination with a series reactor having proper harmonic content.

) 결선으로 단락 제거하며, 나머지 제5 고조파 등은 잔존한다. 따라서 제5 고조파에서 콘덴서와 직렬 공진하는 직렬 리액터를 직렬로 삽입함으로써 회로전압 파형의 왜곡을 경감시키고 콘덴서 투입시의 돌입전류를 억제한다. 이때, 직렬 리액터의 용량 선정은 콘덴서 용량의 리액턴스로 결정된다. The lines contain harmonic voltages due to magnetic saturation of transformers, and the harmonic voltages increase as the capacitors are connected. However, the third harmonic voltage is the delta of the transformer low voltage side (

) Short circuit is removed by the wiring, and the remaining fifth harmonics and the like remain. Therefore, by inserting a series reactor in series resonance with the capacitor at the fifth harmonic, the distortion of the circuit voltage waveform is reduced and the inrush current at the time of capacitor input is suppressed. At this time, the capacity selection of the series reactor is determined by the reactance of the capacitor capacity.

In the series reactor applied to the advanced capacitor, the harmonics existing in the general circuit are above the fifth harmonic, the reactance 6% is applied to the circuits above the fifth harmonic, the third harmonic is generated for the train load and the arc load, and the reactance is 13 to 15%. If there is a large capacity rectifier load and welder, reactance 8 ~ 13% can be applied according to the generated amount.

Capacitors and series reactors may cause accidents due to overvoltage, ambient temperature, dust adhesion, inflow of overcurrent, abnormality due to poor contact, and may naturally deteriorate due to local and accidental insulation degradation.

However, it is very difficult for the condenser and the series reactor to understand the deterioration state and estimate the remaining life in the current state, and there is an urgent need for a technique for determining the deterioration of the condenser or the condenser bank.

As a prior art document, registered utility model publication No. 20-0318656 (July 02, 2003) discloses a technical content of a capacitor bank diagnostic apparatus for power based on neutral current information.

The power condenser bank diagnosing device based on the neutral point current information of the prior art includes a current transformer mounted on a neutral point resistor disposed between the neutral point of the power capacitor bank and the ground to flow the neutral point current flowing into the neutral point resistor, and the secondary side of the current transformer. A current-voltage conversion circuit for converting a current obtained from the voltage into a voltage, an analog filter circuit for receiving unnecessary DC components and noise by receiving a neutral point current flowing into the neutral point resistor through a current transformer, and a continuous analog neutral point from the analog filter circuit. After receiving the current, the discrete Fourier transform (DFT) is used to convert the discrete discrete current signal.The discrete discrete current signal is fast Fourier transformed (FFT) and analyzed by frequency domain. , The fundamental wave (60 Hz) current value of the neutral current If it becomes bigger, it is judged that abnormality of three-phase unbalance occurs in the capacitor bank.If the value of three harmonics (180Hz) of the fundamental wave (60Hz) of the neutral current increases or decreases more than three times the value of one phase, the capacitor or reactor in the capacitor bank Degradation judgment system that outputs relay drive control signal by judging that abnormal value is changed, and fundamental wave of neutral current (60Hz) necessary for diagnostic analysis of capacitor bank to inform user the state of capacitor bank for power in the field. 3 harmonics (180Hz), 3 times the value and fundamental wave, 5 harmonics (300Hz) value, 5 times the fundamental wave, on the numeric LCD, and a display device that shows the abnormality of the current capacitor bank on the normal LED and the bad LED, And a battery charging circuit for automatically charging a power supply battery for supplying driving power to each component with a voltage supplied by the current-voltage conversion circuit. It is configured.

The power capacitor bank diagnostic apparatus of the prior art neutral point current information is used to diagnose the deterioration of the capacitor bank only by the neutral point current flowing through the neutral point of the molded connection, and to compensate the power factor to stabilize the grid voltage.

The capacitor bank is composed of a myriad of capacitor elements in series and in parallel, and when the capacitor bank deteriorates, the capacitor elements are destroyed, thereby reducing the capacitance (C) value.

Assuming that the capacitance is destroyed asymmetrically for each phase and each capacitor, a combination of two capacitor banks of Y connection is detected to detect the image voltage appearing between the neutral points of the two capacitor banks, and then the degree of degradation is diagnosed by the magnitude. The neutral points of the two capacitor banks can be connected to detect the flowing image current and diagnose the degree of degradation.

This method of diagnosing the deterioration of the power capacitor bank based on the neutral current information is necessary for two capacitor banks of Y connection, and it is impossible to detect the deterioration state when the capacitor deteriorates symmetrically. There is a problem in that insulation oil leakage or abnormal filling phenomenon cannot be detected.

The present invention analyzes the information of the input voltage and input current, detects the capacitance (C, L) value and the leakage resistance (R) value of each capacitor and series reactor, and predicts the deterioration state and the degree of deterioration of the capacitor. Prediction and countermeasures against performance deterioration can be established, minimizing the propagation of failures, preventing accidents of capacitors and series reactors, and predicting deterioration of capacitor banks that can contribute to the stable operation of capacitors in steady state. An apparatus and a method thereof are provided.

In addition, the present invention provides a capacitor bank that can monitor the degree of overload of harmonics because the series reactors that are manufactured and operated at a capacity matching the capacitor rating are higher than those of the capacitor, compared to a capacitor having a spare capacity for harmonics. An apparatus for predicting degradation and a method thereof are provided.

), 기본파 및 제n 고조파 임피던스(Z₁, Z₂)를 연산하는 단계; b) 상기 역률 및 임피던스 값을 이용해 상기 콘덴서 뱅크의 각 콘덴서의 누설 저항(R), 각 콘덴서에 대한 임피던스(X_C), 각 직렬 리액터에 대한 임피던스(X_L)를 연산하는 단계; c) 상기 기본파 및 제n 고조파 임피던스(Z₁, Z₂)를 이용하여 상수분을 제거하고 상기 각 직렬 리액터의 용량(L) 및 상기 각 콘덴서의 용량(C)을 연산하는 단계; 및 d) 상기 각 직렬 리액터의 용량(L), 상기 각 콘덴서의 용량(C) 및 누설 저항(R), 소비 전력의 변화 상태를 감시 및 추적하여 상기 각 콘덴서 또는 직렬 리액터의 열화 상태와 상기 각 콘덴서의 용량(C)의 감소에 따른 성능을 예측하는 단계를 포함한다.The present invention relates to an apparatus for predicting degradation of a capacitor bank and a method thereof, wherein the method for predicting degradation of a capacitor bank includes: a capacitor connected to a low voltage, high voltage, and special high voltage power system; A method of predicting deterioration of a capacitor bank performed by a deterioration predictor for predicting deterioration of a capacitor bank including a series reactor, the method comprising: a) collecting current (I) and voltage (V) information inputted to the capacitor bank; Wave voltage (V ₁ ) and current (I ₁ ), n (n> 1) harmonic voltage (V _n ) and current (I _n ), active power (P), power factor (

Calculating the fundamental wave and the nth harmonic impedance (Z ₁ , Z ₂ ); b) calculating leakage resistance (R) of each capacitor in the capacitor bank, impedance (X _C ) for each capacitor, and impedance (X _L ) for each series reactor using the power factor and impedance values; c) removing water content using the fundamental and nth harmonic impedances (Z ₁ , Z ₂ ) and calculating the capacitance (L) of each series reactor and the capacitance (C) of each capacitor; And d) monitoring and tracking changes in the capacity (L) of each series reactor, the capacity (C) and leakage resistance (R) of each condenser, and the power consumption so as to deteriorate the state of each condenser or series reactor and the respective Predicting the performance according to the reduction of the capacitor (C) of the capacitor.

The step d) may further include d-1) predicting a current increase state of the capacitor and detecting an overload degree of the series reactor and a deterioration degree of the capacitor using the predicted current increase state. have.

And, the d) step d-2) if the detection value of the overload degree of the series reactor and the deterioration degree of the capacitor reaches a first set value, an alarm is generated, and if the detected value reaches a second set value The method may further include performing a power off function.

Meanwhile, the capacity L of the series reactor may be calculated based on the following equation.

 In addition, the capacitor C of the capacitor may be calculated based on the following equation.

In addition, the relationship between the fundamental wave voltage V ₁ and the fundamental wave current I ₁ may be calculated based on the following equation.

The relationship between the nth (n> 1) harmonic voltage V _n and the current I _n may be calculated based on the following equation.

), 기본파 및 제n 고조파 임피던스(Z₁, Z₂), 각 콘덴서의 누설 저항(R), 각 콘덴서에 대한 임피던스(X_C), 각 직렬 리액터에 대한 임피던스(X_L), 콘덴서 용량(C) 및 직렬 리액터 용량(L)를 연산하는 연산부; 상기 연산부의 연산 결과를 토대로 콘덴서의 열화 상태, 콘덴서의 전류 증가 상태 예측, 콘덴서 용량(C) 값을 모니터링하여 기준 값 이하로 감소하면 콘덴서 불량으로 판단하고, 상기 예측된 전류증가 상태를 이용해 상기 직렬 리액터의 과부하 정도 및 콘덴서 열화 정도를 감지하는 제어부; 상기 제어부의 제어에 따라 상기 직렬 리액터의 과부하 정도 및 콘덴서 열화 정도의 감지값이 제1설정값에 도달하면 경보를 발생하는 경보부; 및 상기 제어부의 제어에 따라 상기 직렬 리액터의 과부하 정도 및 콘덴서 열화 정도의 감지값이 제2 설정값에 도달하면 전원을 차단하는 전원차단부를 포함한다.On the other hand, the deterioration prediction apparatus of the capacitor bank is a capacitor that predicts deterioration of a capacitor bank including a capacitor connected to a low voltage, high voltage, and special high voltage power system, and a series reactor inserted in series with the capacitor and resonating in series with the capacitor. In the deterioration prediction apparatus of a bank, input current (I) and voltage (V) information are collected, and the fundamental wave voltage (V ₁ ) and the current (I ₁ ), n (n> 1) harmonic voltage (V _n ) And current (I _n ), active power (P), power factor (

), Fundamental and nth harmonic impedance (Z ₁ , Z ₂ ), leakage resistance (R) of each capacitor, impedance (X _C ) for each capacitor, impedance (X _L ) for each series reactor, and capacitor capacity ( C) and an operation unit for calculating the series reactor capacity (L); Based on the calculation result of the calculation unit, the deterioration state of the capacitor, the current increase state prediction of the capacitor, and the capacitor capacity (C) value are monitored and the value decreases below the reference value. A control unit for detecting the degree of overload of the reactor and the degree of deterioration of the capacitor; An alarm unit for generating an alarm when the detected values of the degree of overload and capacitor deterioration of the series reactor reach a first set value under control of the controller; And a power cut-off unit which cuts off power when the detected values of the degree of overload and the degree of condenser deterioration of the series reactor reach a second set value under the control of the controller.

The display unit may further include a display unit displaying a deterioration state of the condenser and the series reactor and a current increase state of the condenser and the series reactor under a control of the controller in a graph or a numerical value.

The calculator may calculate the capacity L of the series reactor based on the following equation.

The calculator may calculate the capacitor C of the capacitor based on the following equation.

The deterioration prediction apparatus and method of the capacitor bank of the present invention analyze the information of the input voltage and the input current, detect the capacitance (C, L) value and the leakage resistance (R) value of each capacitor and the series reactor to deteriorate the state and the capacitor. By predicting the degree of degradation of the capacitor, it is possible to establish the life expectancy of the capacitor and countermeasures due to the decrease in performance, and to minimize the propagation of the failure to prevent the accident of the capacitor and the series reactor in advance. Provides an effect that can contribute to driving.

In addition, the deterioration predicting apparatus and method of the capacitor bank of the present invention have a higher burnout rate than the capacitor because the series reactors manufactured and operated with the capacity corresponding to the capacitor rating are higher than those of the capacitor having the spare capacity against harmonics. Incremental status information detects the overload of the serial reactor and provides the ability to alarm and shut off.

1 is a block diagram illustrating a capacitor bank applied to an apparatus for predicting degradation of a capacitor bank according to the present invention.
FIG. 2 is a block diagram illustrating the degradation prediction apparatus of FIG. 1.
3 is an equivalent circuit diagram illustrating a connection relationship between a capacitor and a series reactor in the capacitor bank of FIG. 1.
4 is a flowchart illustrating a deterioration prediction method of a capacitor bank according to the present invention.

Description of the present invention is only an embodiment for structural or functional description, the scope of the present invention should not be construed as limited by the embodiments described in the text. That is, the embodiments are to be construed as being variously embodied and having various forms, so that the scope of the present invention should be understood to include equivalents capable of realizing technical ideas. Also, the purpose or effect of the present invention should not be construed as limiting the scope of the present invention, since it does not mean that a specific embodiment should include all or only such effect.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used predefined terms should be interpreted to be consistent with the meanings in the context of the related art and can not be interpreted as having ideal or overly formal meaning unless explicitly defined in the present invention.

1 is a block diagram illustrating a capacitor bank applied to an apparatus for predicting degradation of a capacitor bank according to the present invention.

Referring to FIG. 1, the capacitor bank 10 is a system in which at least one or more capacitors 11 are used in a large capacity in series or parallel connection, and not only N (N> 1) capacitors 11 but also a series reactor 12. ), A discharge device 13 and a protective device 14.

In this case, the discharge device 13 discharges the residual voltage remaining after the power supply is turned off by the capacitor 11, and uses an internal discharge resistor or a discharge coil.

In addition, the protection facility 14 performs a function of improving the power factor, determining the capacity, reducing the failure rate or the accident rate of the capacitor 11 or various protection devices in the capacitor bank 10, and calculating and Perform the judgment function.

The protection device of such a protective installation may further include a degradation prediction device 15 for predicting deterioration of each capacitor 11 and the series reactor 12 in the capacitor bank.

FIG. 2 is a block diagram illustrating the degradation prediction apparatus of FIG. 1.

Referring to FIG. 2, the degradation prediction apparatus 15 may include an information collector configured to collect voltage and current information, and calculate the collected information such that V ₁ , I ₁ , V _n , The deterioration state of the condenser 11 and the current of the condenser 11 based on the calculation result of the calculation unit 15a and the calculation unit 15a for calculating I _n , Z, P, R, X _C , X _L , L, C, and the like. Predicting an increase state and monitoring the value of the capacitor capacity (C), if the value falls below the reference value, the capacitor is judged to be defective, and the overload degree of the series reactor 12 and the degree of deterioration of the capacitor 11 are detected using the predicted current increase state. Under the control of the control unit 15b and the control unit 15b, an alarm unit 15c for generating an alarm when the detected value of the overload degree of the series reactor 12 and the deterioration degree of the condenser 11 reaches the first set value, the series When the detected value of the overload degree of the reactor 12 and the deterioration degree of the condenser 11 reaches the second set value, the condenser 11 and the control unit 15d for shutting off the power and the control unit 15b are controlled. Graph of deterioration of series reactor 12 and current increase of condenser 11 and series reactor 12 Includes a display unit (15e) that displays the numbers.

In general, since the capacitor 11 may be determined to be defective when the capacitor 11 is reduced by 5% or more, the power cut-off unit 15d may set the first set value to 3% and the second based on the reference capacitor of the capacitor 11. Although the set value can be set to 5%, the first set value and the second set value can be changed according to the state of the capacitor 11 or the capacitor bank 10, the state of the power system to which the capacitor bank 10 is applied, and the like. .

3 is an equivalent circuit diagram illustrating a connection relationship between a capacitor and a series reactor in the capacitor bank of FIG. 1.

Referring to FIG. 3, the capacitor bank 10 is inserted into a capacitor 11 connected to a low, high and special high voltage power system, an internal leakage resistance R of the capacitor 11, and a capacitor 11 in series. And a series reactor 12 in series resonance with (11). The leakage resistance R may vary depending on the shape of the capacitor, the dielectric material, and the like as well as the lead wire resistance.

4 is a flowchart illustrating a method of predicting degradation of a capacitor bank according to an embodiment of the present invention.

), 기본파 임피던스(Z₁) 및 제n 고조파 임피던스(Z₂)를 연산한다.(단계 S1 및 S2)Referring to FIG. 4, in the deterioration prediction method of the capacitor bank, the degradation prediction device 15 collects current I and voltage V information input to the capacitor bank 10 to obtain a fundamental wave voltage V ₁ and Current (I ₁ ), nth harmonic voltage (V _n ) and current (I _n ), active power (P), power factor (

), The fundamental wave impedance (Z ₁ ), and the nth harmonic impedance (Z ₂ ) are calculated (steps S1 and S2).

In this case, the relationship between the fundamental wave voltage V ₁ and the fundamental wave current I ₁ is equal to Equation 1 when impedance (harmonic rejection) is applied at 60 Hz, and the nth harmonic voltage V _n and the current I _{n are applied} . When the impedance is applied at the fifth harmonic (300 Hz) is shown in Equation 2. For example, the fifth harmonic is calculated in Equation 2, but it can be calculated by applying any order harmonics (for example, n = 1, n = 3, n = 5, etc.).

[Equation 1]

&Quot; (2) "

은 기본파 전압 및 전류, 임피던스, 리액턴스, 역률각을 각각 나타낸다.
In Equations 1 and 2, V _n is a corresponding harmonic (5th harmonic) voltage, I _n is a corresponding harmonic (5th harmonic) current,

Denotes fundamental wave voltage and current, impedance, reactance and power factor, respectively.

Equation 1 and Equation 2 can be summarized as Equation 3, Equation 4 and Equation 5 as Z = V / I.

&Quot; (3) "

&Quot; (4) "

[Equation 5]

)의 관계는 수학식6과 같다. Active power (P) and power factor (

) Is as shown in equation (6).

[Equation 6]

V, I, Q, and Z in Equations 5 and 6 are combined voltages, currents, phase angles, and impedances including fundamental and harmonics.

The degradation prediction device 15 uses a power factor and an impedance value to detect the leakage resistance R of each capacitor 11 of the capacitor bank 10, the impedance X _C for each capacitor 11, and each series reactor 12. Calculate the impedance X _L for each (step S3).

[Equation 7]

을 제거하면 직렬 리액터(12)의 용량(L) 및 상기 각 콘덴서의 용량(C)을 산출할 수 있다. (단계 S4)Using Equations 3 and 4

By removing, the capacitance L of the series reactor 12 and the capacitance C of each capacitor can be calculated. (Step S4)

은 수학식3에서 5를 곱한 후에 수학식4를 빼면 제거될 수 있다. That is, as shown in equation (8),

May be removed by multiplying Equation 3 by 5 and subtracting Equation 4.

&Quot; (8) "

Equation (9) is derived by solving Equation (8) with the root formula.

&Quot; (9) "

After substituting Equation 3 for L and substituting Equation 9, the capacity L of the series reactor 12 is calculated as in Equation 10, and the capacity C of the condenser 11 is calculated as in Equation 11. do.

&Quot; (10) "

[Equation 11]

The degradation prediction device 15 monitors the change state of the capacitance L of each series reactor 12 in the capacitor bank 10, the capacitance C of each capacitor 11, the leakage resistance R, and the power consumption. By tracking, the deterioration state of each condenser 11 and the performance according to the decrease of the capacity | capacitance C of each condenser 11 are estimated. (Step S5).

In addition, the degradation prediction apparatus 15 may detect the degree of overload of the series reactor 12 and the degree of deterioration of the capacitor 11 by using the predicted current increase state after predicting the current increase state of the condenser 11. When the detected value of the overload degree of the series reactor 12 and the deterioration degree of the condenser 11 reaches the first set value, an alarm is generated and the overload degree of the series reactor 12 and the deterioration degree of the condenser 11 are generated. If the detected value exceeds the first setting value and reaches the second setting value, the power-off function is performed (steps S6 and S7).

The deterioration prediction device 15 also includes a monitor device (display unit) such as an LCD, and the deterioration state of the condenser 11 and the series reactor 12 predicted by the operator to the monitor device, and performance prediction information of the condenser 11. In addition, detection information on the degree of overload of the series reactor 12 and the degree of deterioration of the condenser 11 may be displayed using a graph or a numerical value.

Deterioration prediction methods that are conventionally performed in various ways are difficult to prevent substantial accidents, and even though internal equilibrium failures occur in conventional failure prediction methods, the detection of degradation of the capacitor bank according to an embodiment of the present invention is not possible. The method compares the fundamental and harmonic orders, summarizes Equations 1 to 11, and predicts the deterioration state of the condenser 11 and the series reactor 12, so that failures due to leakage of the condenser 11 can be detected in advance.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims It can be understood that

10: condenser bank 11: condenser
12 series reactor 13 discharge device
14 protective equipment 15 deterioration prediction device

Claims (11)

Prediction of deterioration of a capacitor bank performed by a deterioration prediction device for predicting deterioration of a capacitor bank including a capacitor connected to a low voltage, high voltage, and special high voltage power system, and a series reactor inserted in series with the capacitor and resonating in series with the capacitor. In the method,
a) Collecting information of current (I) and voltage (V) input to the capacitor bank, the fundamental wave voltage (V ₁ ) and current (I ₁ ), n (n> 1) harmonic voltage (V _n ) and current (I _n ), active power (P), power factor (

Calculating the fundamental wave and the nth harmonic impedance (Z ₁ , Z ₂ );
b) calculating leakage resistance (R) of each capacitor in the capacitor bank, impedance (X _C ) for each capacitor, and impedance (X _L ) for each series reactor using the power factor and impedance values;
c) removing water content using the fundamental and nth harmonic impedances (Z ₁ , Z ₂ ) and calculating the capacitance (L) of each series reactor and the capacitance (C) of each capacitor; And
d) monitoring and tracking the changes in the capacity (L) of each series reactor, the capacity (C) and leakage resistance (R) of each capacitor, and the power consumption, and the deterioration state of each capacitor or series reactor and each capacitor Predicting the performance according to the reduction of the capacity (C) of the capacitor bank deterioration prediction method.
The method of claim 1, wherein step d)
d-1) predicting a current increase state of the capacitor, and using the predicted current increase state to detect the degree of overload of the series reactor and the degree of deterioration of the capacitor. Way.
The method of claim 2, wherein d)
d-2) generating an alarm when the detected value of the overload degree of the series reactor and the deterioration degree of the capacitor reaches a first set value, and performing a power off function when the detected value reaches the second set value. Deterioration prediction method of a capacitor bank further comprising.
The method of claim 1, wherein the capacity (L) of the series reactor is
&Quot; (10) "

The deterioration prediction method of a capacitor bank, characterized in that it is calculated based on the above equation.
The method of claim 1, wherein the capacitor (C) of the capacitor
&Quot; (11) "

The deterioration prediction method of a capacitor bank, characterized in that it is calculated based on the above equation.
The relationship between the fundamental wave voltage V ₁ and the fundamental wave current I ₁ of claim 1, wherein
[Equation 1]

The deterioration prediction method of a capacitor bank, characterized in that it is calculated based on the above equation.
The method of claim 1, wherein the relationship between the nth harmonic voltage V _n and the current I _n is
&Quot; (2) "

The deterioration prediction method of a capacitor bank, characterized in that it is calculated based on the above equation.
A deterioration prediction apparatus for a condenser bank for predicting deterioration of a condenser bank including a capacitor connected to a low voltage, high voltage, and special high voltage power system, and a series reactor inserted in series with the condenser and resonating in series with the condenser.
Input current (I) and voltage (V) information to collect the fundamental wave voltage (V ₁ ) and current (I ₁ ), n (n> 1) harmonic voltage (V _n ) and current (I _n ), effective Power (P), power factor (

), Fundamental and nth harmonic impedance (Z ₁ , Z ₂ ), leakage resistance (R) of each capacitor, impedance (X _C ) for each capacitor, impedance (X _L ) for each series reactor, and capacitor capacity ( C) and an operation unit for calculating the series reactor capacity (L);
Based on the calculation result of the calculation unit, the deterioration state of the capacitor, the current increase state prediction of the capacitor, and the capacitor capacity (C) value are monitored and the value decreases below the reference value. A control unit for detecting the degree of overload of the reactor and the degree of deterioration of the capacitor;
An alarm unit for generating an alarm when the detected values of the degree of overload and capacitor deterioration of the series reactor reach a first set value under control of the controller; And
And a power cut-off unit which cuts off the power when the detected values of the overload degree and the capacitor deterioration degree of the series reactor reach a second set value under the control of the controller.
9. The method of claim 8,
And a display unit for displaying the deterioration state of the condenser and the series reactor and the increase state of the current of the condenser and the series reactor under a control of the controller in a graph or a numerical value.
The method of claim 8, wherein the operation unit
&Quot; (10) "

And the capacity (L) of the series reactor is calculated based on the above equation.
The method of claim 8, wherein the operation unit
&Quot; (11) "

And a capacitor (C) of the capacitor is calculated based on the above equation.

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