JP2008124146A - Method and apparatus for estimating degradation level of oil-filled electric equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the degradation level estimation accuracy of oil-filled electric equipment. <P>SOLUTION: Previously, based on the amount of a degraded product in the insulation oil of oil-filled electric equipment, the accumulated load amount obtained by accumulating loads applied to the oil-filled electric equipment with time, data of the machine strength index of insulating paper, correlation data between the accumulated load amount and the machine strength index of the insulating paper is created for each predetermined range of the degraded product. Based on the amount of the degraded product measured from the insulation oil of the target oil-filled electric equipment for estimating a degradation level, correlation data between the accumulated load amount and the average degree of polymerization for use in the estimation of the degradation level of the target oil-filled electric equipment is selected. Based on the selected correlation data between the accumulated load amount and the mechanical strength index of the insulating paper. The estimate value of the mechanical strength index of the insulating paper is determined from the measured accumulated load amount of the target oil-filled electric equipment. Based on the estimate value of the mechanical strength index of the insulating paper, the degradation level of the target oil-filled electric equipment is estimated. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for estimating a deterioration level of an oil-filled electrical device.

The degree of deterioration of oil-filled electrical equipment is estimated by the degree of deterioration of insulating paper used in oil-filled electrical equipment. That is, the degree of deterioration of the insulating paper can be evaluated by a mechanical strength index such as tensile strength and degree of polymerization. However, in order to measure the mechanical strength of insulation paper for oil-filled electrical equipment, it is necessary to stop the oil-filled electrical equipment and collect and measure a sample of insulation paper from within the oil-filled electrical equipment. It is not realistic considering the cost. For this reason, a method of evaluating the degree of deterioration of insulating paper by component analysis in insulating oil is used. As an example, we evaluated the degree of deterioration of insulating paper from CO + CO ₂ (sum of carbon monoxide and carbon dioxide) in insulating oil generated in insulating oil due to deterioration of insulating paper, and furfural. The degree of deterioration is estimated (Patent Document 1).

In addition, the degree of deterioration of the insulating paper is more likely to deteriorate as the temperature of the oil-filled electrical device in use is higher, and less likely to deteriorate as the temperature is lower. The temperature during use of the oil-filled electrical device depends on the load state of the oil-filled electrical device, and the temperature increases as the load increases. Further, when the oil-filled electrical device is operated at the same temperature, the insulating paper deteriorates as the operation time becomes longer. Accordingly, there has been proposed a technique for obtaining the degree of deterioration of insulating paper in consideration of the operation time of oil-filled electrical equipment and the temperature experienced by insulating paper during operation (Patent Document 2).
JP-A-8-31653 JP-A-7-159471

The inventors of the present invention measured CO + CO ₂ and furfural in insulating oil from oil-filled electrical equipment that was actually used and replaced properly for a predetermined period of time, collected insulating paper, and measured its degree of polymerization. . As a result, the insulating CO + CO ₂ and in the oil, and furfural, the relationship between insulating paper degree of polymerization is large measure of CO + CO ₂ and furfural in insulating oil, certain correlation is low polymerization degree of the insulating paper Is seen, but varies depending on the oil-filled electrical equipment. For this reason, in consideration of only such a correlation, when the degree of deterioration of the oil-filled electrical device is estimated from the measured values of CO + CO ₂ and furfural in the insulating oil, the accuracy is poor. As a result, it may not be possible to accurately determine when to replace oil-filled electrical equipment, and equipment that is still fully usable may be replaced. Even when the temperature experienced by the insulating paper during operation is taken into account, there is room for further improvement in how to consider the degree of deterioration.

  The method of estimating the degree of deterioration of oil-filled electrical equipment according to the present invention includes, in advance, the amount of degradation products in the insulating oil of the oil-filled electrical equipment, and the load integrated amount obtained by integrating the load applied to the oil-filled electrical equipment over time, Based on the data on the mechanical strength index of insulating paper, create correlation data between the load integrated amount and the mechanical strength index of insulating paper for each predetermined range of the amount of degradation products, and estimate the degree of degradation Based on the amount of degradation products measured from the insulation oil of the equipment, select correlation data between the load accumulation amount and average polymerization degree used to estimate the degree of degradation of the target oil-filled electrical equipment, and select the load accumulation Based on the correlation data between the quantity and the mechanical strength index of the insulating paper, the estimated value of the mechanical strength index of the insulating paper is obtained from the measured load integrated quantity of the target oil-filled electrical equipment, and the mechanical strength index of the insulating paper is estimated. Estimate the degree of degradation of the target oil-filled electrical equipment based on the value It is characterized in Rukoto.

  According to this method for estimating the degree of deterioration of oil-filled electrical equipment, for each predetermined range of the amount of deteriorated product, correlation data between the load integrated amount and the mechanical strength index of insulating paper is created, and the target oil for estimating the degree of deterioration Based on the amount of degradation products measured from the insulating oil of the input electrical equipment, select the correlation data between the integrated load amount used to estimate the degree of degradation of the target oil-filled electrical equipment and the average degree of polymerization, and measure Since the estimated value of the mechanical strength index of the insulating paper is obtained from the load integrated amount of the target oil-filled electrical device, the degree of deterioration of the oil-filled electrical device can be estimated with higher accuracy.

  Hereinafter, an oil-filled electrical equipment deterioration degree estimation method and apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  This method of estimating the degree of deterioration of oil-filled electrical equipment is based on the amount of degradation products in the insulation oil of oil-filled electrical equipment, the load accumulated amount obtained by integrating the load applied to the oil-filled electrical equipment over time, and the insulation paper Based on the data of the mechanical strength index, correlation data between the load integrated amount and the mechanical strength index of the insulating paper is created for each predetermined range of the degradation product amount.

Examples of the degradation product in the insulating oil include (CO + CO ₂ ), furfural, and acetone in the insulating oil. These products are causal to the deterioration of the insulating paper and can be measured with relatively high accuracy. At the same time, there is a certain correlation between the amount of product in the insulating oil and the mechanical strength of the insulating paper. The relationship is recognized. In addition, the degradation product in insulating oil is not limited to what was mentioned above. The amount of degradation product in the insulating oil may be a relative amount with respect to the total weight of the insulating paper contained in the oil-filled electrical device so that relative evaluation is possible for different types of oil-filled electrical devices. . In addition, when evaluating a deterioration degree about the same kind of oil-filled electric equipment, you may evaluate the amount of deterioration products in insulating oil using an absolute amount.

In this embodiment, data obtained by relative evaluation of the amount of CO + CO ₂ (sum of carbon monoxide and carbon dioxide) as a degradation product with respect to the total weight of the insulating paper is used. Specifically, first, a sample of insulating oil is taken out from the oil-filled electrical device, and the amount of CO + CO ₂ contained in a unit amount (for example, 1 liter) of insulating oil is measured. Then, the amount of the insulating oil of the oil-filled electrical device is integrated to obtain an estimated value of the total amount of CO + CO ₂ contained in the insulating oil of the oil-filled electrical device. Next, since the amount of these degradation products is due to the amount of paper immersed in insulating oil, such as insulating paper and pressboard used in oil-filled electrical equipment, the estimated value of the total amount of CO + CO ₂ is calculated. Divide by the total weight of paper immersed in insulating oil. Thereby, the estimated value of the amount of CO + CO ₂ produced per unit weight of the paper immersed in the insulating oil is calculated.

  Next, for example, an average degree of polymerization or tensile strength may be used as the mechanical strength index of the insulating paper. Both are indicators for measuring the degree of deterioration of insulating paper. In this embodiment, the average degree of polymerization is used as a mechanical strength index of insulating paper.

The load integrated amount obtained by integrating the load applied to the oil-filled electrical equipment over time is an amount equivalent to the cumulative amount of heat generation of the oil-filled electrical equipment over time, which is one of the factors that promote the deterioration of insulating paper. . Here, for convenience, for example, the calculation is performed using the load factor of the oil-filled electrical device. The load factor is the ratio of the load during operation to the rated capacity of the oil-filled electrical device. For example, in oil-filled transformers, the load loss is known to be proportional to the square of the load factor (Noboru Ooka, Sadao Maekawa, “Transformer”, first edition, Tokyo Denki University Press, P169, etc. ). In addition, the highest point temperature rise of the winding is known to be proportional to approximately 1.6th power of the load factor (Institute of Electrical Engineers Technical Report (Part I) No. 143, Oil-filled Transformer Operation Guidelines, Transformer Instrument reliability survey committee, Institute of Electrical Engineers of Japan, P16, etc.). Therefore, in this embodiment, in consideration of the heat generation characteristics of the oil-filled electrical device, an amount obtained by multiplying a value obtained by multiplying the square of the load factor by the winding maximum point temperature rise value [Σ {( Load factor) ² × winding maximum point temperature rise value}] or the amount obtained by multiplying the load factor multiplied by 1.6 to the winding maximum point temperature rise value over time [Σ {(load factor ) ^1.6 x Winding maximum point temperature rise value}] is used as the integrated load. In addition, the amount [Σ (load factor) ² ] obtained by integrating the square of the load factor with time [Σ (load factor) ² ] or the amount obtained by integrating the load factor 1.6 with time [Σ (load factor) ^{1. 6} ] may be used as the load integrated amount.

  Next, correlation data between the load integrated amount used for estimating the deterioration degree of the oil-filled electrical device and the mechanical strength index of the insulating paper is created. Such correlation data is divided into groups for each predetermined range according to the measured deterioration product amount in the insulating oil, and is created for each divided group.

  When creating correlation data between the load integrated amount used to estimate the deterioration degree of such oil-filled electrical equipment and the mechanical strength index of insulating paper, for example, it was actually used properly for a predetermined period and replaced It may be created based on data obtained from oil-filled electrical equipment.

  The deterioration product amount in the insulating oil and the mechanical strength index of the insulating paper may be measured, for example, by taking a sample from an oil-filled electrical device that has been actually used and replaced properly for a predetermined period of time. Further, the load integrated amount obtained by integrating the load applied to the oil-filled electrical device over time may be calculated from, for example, history data that records the usage status of the oil-filled electrical device. Specifically, in oil-filled transformers used in substations, etc., when the load factor displacement and monthly load factor per unit time are recorded in time series, this history data is used. The load applied to the oil-filled electrical device may be integrated over time and can be calculated relatively easily.

In this embodiment, samples are collected from a plurality of oil-filled electrical devices that have been used and replaced properly for a predetermined period of time, and the amount of CO + CO ₂ generated in the insulating oil of the oil-filled electrical device (strictly speaking, insulation The amount of CO + CO ₂ produced from the unit weight of the paper immersed in oil is hereinafter simply referred to as “production amount”) and the average degree of polymerization of the insulating paper is measured. Also, Σ {(time load factor) ² × winding maximum point temperature rise value} is calculated from the history data of the usage state of each oil-filled electrical device. FIG. 1 is a diagram showing the relationship between the amount of CO + CO ₂ produced and the average degree of polymerization for a plurality of oil-filled electrical devices that were actually used and replaced properly for a predetermined period of time.

Next, based on the amount of CO + CO ₂ generated, the data is divided into groups, and correlation data between the load integrated amount and the average polymerization degree of the insulating paper is created for each group.

In this embodiment, the plurality of oil-filled electrical devices described above are grouped based on the amount of CO + CO ₂ produced. Specifically, a plurality of oil-filled electrical devices having a CO + CO ₂ production amount of less than 20 (ml / Kg), 20 (ml / Kg) or more and less than 30 (ml / Kg), 30 ( ml / Kg) or more and less than 40 (ml / Kg), 40 (ml / Kg) or more and less than 70 (ml / Kg), 70 (ml / Kg) or more and less than 110 (ml / Kg), 110 (Ml / Kg) Divided into 6 groups.

Then, for each group, correlation data between Σ {(time load factor) ² × winding maximum point temperature rise value} and the average degree of polymerization of the insulating paper is created. FIG. 2 is for a group in which the amount of CO + CO ₂ produced is less than 20 (ml / Kg), and FIG. 3 is for a group in which the amount of CO + CO ₂ produced is 20 (ml / Kg) to less than 30 (ml / Kg). FIG. 4 is for a group in which the production amount of CO + CO ₂ is 30 (ml / Kg) or more and less than 40 (ml / Kg), and FIG. 5 is the production amount of CO + CO ₂ is 40 (ml / Kg). ) For a group of 60 (ml / Kg) or less and FIG. 6 is for a group in which the amount of CO + CO ₂ produced is 70 (ml / Kg) or more and less than 110 (ml / Kg). Is for a group in which the amount of CO + CO ₂ produced is 110 (ml / Kg) or more.

Thus, by creating correlation data between Σ {(time load factor) ² × winding highest point temperature rise value} and the average degree of polymerization of the insulating paper for each predetermined range of the degradation product amount, Σ { (Time load factor) The error rate of the correlation between ² × winding highest point temperature rise value} and the average degree of polymerization of the insulating paper can be reduced. Therefore, if the degree of deterioration of the oil-filled electrical device is estimated using this correlation data, a more accurate determination can be made regarding the degree of degradation of the oil-filled electrical device. In this embodiment, the correlation between the estimated value of the average polymerization degree of the insulating paper and the actually measured value and the error average are as shown in FIG. FIG. 9 is a diagram showing a correlation between an estimated average polymerization degree of insulating paper and an actual measurement value and an error average obtained from a correlation between the amount of CO + CO ₂ generated and the average polymerization degree of the insulating paper. The error average shown here is an average value of values obtained by dividing the difference between the estimated value of the average degree of polymerization of the insulating paper and the actually measured value by the actually measured value. Therefore, it is shown that the estimation error of the deterioration degree of the oil-filled electrical device is smaller as the error average is smaller.

  Next, an operation for estimating the degree of deterioration will be described for the target oil-filled electrical device to be estimated for estimating the degree of deterioration. In such estimation work, first, the load integrated amount used to estimate the degree of deterioration of the target oil-filled electrical device based on the amount of degradation product measured from the insulating oil of the target oil-filled electrical device whose degree of degradation is estimated. And correlation data of average degree of polymerization is selected.

In this embodiment, Σ {(time load factor) used to estimate the degree of deterioration of the target oil-filled electrical device based on the amount of degradation product (CO + CO ₂ ) measured from the insulating oil of the target oil-filled electrical device. ² × Correlation data of winding maximum point temperature rise value} and average degree of polymerization are selected.

In the estimation work of the deterioration degree of the oil-filled electrical device, the oil-filled electrical device actually used can be used as a target. In this case, first, a part of the insulating oil is collected as a sample from the oil-filled electrical equipment that is actually used, and the amount of deteriorated product is measured therefrom. In this embodiment, correlation data between the integrated load amount and the average degree of polymerization of the insulating paper is created using the amount of CO + CO ₂ produced as the amount of deteriorated product, so the measurement result of the amount of CO + CO ₂ produced is used. . Then, based on the measurement result of the CO + CO ₂ production amount, correlation data between the load integrated amount to be used and the average polymerization degree is selected.

In this embodiment, the amount of CO + CO ₂ produced is less than 20 (ml / Kg), 20 (ml / Kg) or more and less than 30 (ml / Kg), 30 (ml / Kg) or more and 40 (ml / kg). Kg), 40 (ml / Kg) or more and less than 70 (ml / Kg), 70 (ml / Kg) or more and less than 110 (ml / Kg), 110 (ml / Kg) or more Since it is divided into groups, a group including the measurement result may be selected based on the measurement result of the CO + CO ₂ generation amount.

  Next, calculate the load integrated amount from the usage history data of the target oil-filled electrical device, and measure the load of the oil-filled electrical device measured based on the correlation data between the selected load integrated amount and the mechanical strength index of the insulating paper. The estimated value of the mechanical strength index of insulating paper is obtained from the integrated amount.

In this embodiment, because of the use of sigma {(time load factor) ² × winding highest point temperature rise value} as the accumulated load amount, the usage history data of the target oil-filled electrical apparatus sigma {(time load factor) ² X Winding highest point temperature rise value} is calculated. And the calculated Σ {(time load factor) ² × winding highest point temperature rise value}, selected Σ {(time load factor) ² × winding highest point temperature rise value} and the average polymerization degree of the insulating paper The average degree of polymerization of the insulating paper of the target oil-filled electrical device is obtained on the basis of the correlation data. Specifically, in this embodiment, the target oil is obtained from an approximate curve indicating the correlation between the selected Σ {(time load factor) ² × winding highest point temperature rise value} and the average degree of polymerization of the insulating paper. The average degree of polymerization of the insulation paper of the incoming electrical equipment is obtained.

The degree of deterioration of oil-filled electrical equipment is determined by the deterioration of insulation paper in oil-filled electrical equipment, and the deterioration of insulation paper is determined by the mechanical strength of insulation paper. Therefore, according to the mechanical strength index of insulation paper such as average polymerization degree and tensile strength, The degree of deterioration of oil-filled electrical equipment can be estimated. In this embodiment, as described above, Σ {(time load factor) ² × winding highest point temperature rise value} calculated from the use history data of the target oil-filled electrical device and the selected Σ {(time load Rate) ² x winding maximum temperature rise value} and the correlation data of the correlation data between the average polymerization degree of the insulating paper, the average polymerization degree of the insulating paper of the target oil-filled electrical equipment can be obtained, From this, the degree of deterioration of the oil-filled electrical device can be estimated.

  If the amount of degradation products in the insulating oil of oil-filled electrical equipment is the same, the degree of polymerization of the insulating paper increases (the deterioration of the insulating paper decreases) as the oil-filled electrical equipment is operated at a lower load. The degree of polymerization of the insulating paper is smaller as the electric device is operated at a higher load (the deterioration of the insulating paper is larger). According to the above-described method for estimating the degree of degradation of oil-filled electrical equipment, when creating correlation data between the load integrated amount used for estimating the degree of degradation of oil-filled electrical equipment and the mechanical strength index of insulating paper, FIG. As shown in FIG. 7, the amount of degradation products in the insulating oil of the oil-filled electrical equipment, the load accumulated amount obtained by integrating the load applied to the oil-filled electrical equipment over time, and the mechanical strength index data of the insulating paper Is divided into predetermined ranges of the amount of deteriorated products, and correlation data between the load integrated amount and the mechanical strength index of the insulating paper is created for each range. For this reason, the degradation product amount is divided into predetermined ranges, and by creating correlation data between the load integrated amount and the mechanical strength index of the insulating paper for each range, the load integrated amount and the mechanical strength index of the insulating paper are The error rate of the correlation can be reduced.

  And when estimating the deterioration degree of the target oil-filled electrical equipment, the correlation data between the load integrated amount to be used and the average polymerization degree is obtained based on the amount of degradation products measured from the insulating oil of the target oil-filled electrical equipment. Based on the correlation data between the selected load integrated amount and the mechanical strength index of the insulating paper, the estimated value of the mechanical strength index of the insulating paper is obtained from the measured load integrated amount of the target oil-filled electrical device. Since the degree of degradation of the target oil-filled electrical device is estimated based on the estimated value of the mechanical strength index of the insulating paper, the degree of degradation of the target oil-filled electrical device can be estimated more accurately.

  This makes it possible to more accurately determine the degree of deterioration of the oil-filled electrical device when replacing the oil-filled electrical device due to its life, and to replace the oil-filled electrical device at a more appropriate time. it can.

  The oil-filled electrical equipment deterioration level estimation method according to an embodiment of the present invention has been described above. However, the oil-filled electrical equipment degradation level estimation method according to the present invention is not limited to the above-described embodiment.

For example, in the above-described embodiment, Σ {(time load factor) ² × winding maximum point temperature rise value} is adopted as the load integrated amount. However, the present invention is not limited to this, and load factor data is obtained on a daily or monthly basis. In some cases, the integrated amount over time may be calculated based on such time. Also, the load integrated amount is an amount obtained by integrating the load factor squared over time [Σ (load factor) ² ], or an amount obtained by integrating the load factor raised to 1.6 power [Σ ( (Load factor) ^1.6 ] may be used.

In addition, the amount of degradation products may be furfural or acetone in addition to (CO + CO ₂ ) in insulating oil. In addition to the average degree of polymerization of insulating paper, tensile strength may be used as the mechanical strength index of insulating paper.

  In addition, the method of estimating the degree of deterioration of oil-filled electrical equipment is implemented using a computer having a calculation unit (CPU) that performs calculation processing based on a predetermined program and a storage unit (memory) that can store correlation data and the like. Can be

  The oil-filled electrical equipment deterioration degree estimation device is, for example, a pre-degraded amount of degradation product in the insulating oil of the oil-filled electrical equipment, a load integrated amount obtained by integrating the load applied to the oil-filled electrical equipment over time, and insulating paper. A correlation data storage unit that records correlation data between the load integrated amount and the mechanical strength index of the insulating paper, created for each predetermined range of the degradation product amount based on the data of the mechanical strength index of Based on the amount of deterioration products measured from the insulation oil of the target oil-filled electrical equipment to be estimated, select correlation data between the accumulated load to be used and the average polymerization degree from the correlation data stored in the correlation data storage unit Correlation data selection unit, and in the selection unit, based on the correlation data between the load integrated amount selected and the mechanical strength index of the insulating paper, the measured load integrated amount of the oil-filled electrical device Mechanical strength index It may be configured to include an estimation value calculation unit for determining the value.

  Further, in this case, the deterioration degree correlation storage unit that stores the correlation between the estimated value of the mechanical strength index of the insulating paper and the deterioration degree of the oil-filled electrical device, and the estimated value calculated by the estimated value calculation unit Degradation degree calculation unit for calculating the deterioration degree of the oil-filled electrical device based on the correlation between the estimated value of the mechanical strength index of the insulating paper stored in the deterioration degree correlation storage unit and the deterioration degree of the oil-filled electrical device May be provided.

  In addition, this method of estimating the degree of deterioration of oil-filled electrical equipment can be applied to various oil-filled electrical equipment such as oil-filled reactances in addition to oil-filled transformers.

It shows the relationship between the average degree of polymerization and CO + CO _2. Figure generated amount of CO + CO ₂ shows the correlation between the average polymerization degree of 10~20 (ml / Kg) was terms of less than sigma {(time load factor) ² × winding highest point temperature rise value}. Figure generated amount of CO + CO ₂ shows the correlation between the average polymerization degree of 20~30 (ml / Kg) was terms of less than sigma {(time load factor) ² × winding highest point temperature rise value}. Figure generated amount of CO + CO ₂ shows the correlation between the average polymerization degree of 30~40 (ml / Kg) was terms of less than sigma {(time load factor) ² × winding highest point temperature rise value}. Figure generated amount of CO + CO ₂ shows the correlation between the average polymerization degree of 40~70 (ml / Kg) was terms of less than sigma {(time load factor) ² × winding highest point temperature rise value}. Figure generated amount of CO + CO ₂ shows the correlation between the average polymerization degree of 70~110 (ml / Kg) was terms of less than sigma {(time load factor) ² × winding highest point temperature rise value}. Figure generated amount of CO + CO ₂ shows the correlation between the average polymerization degree of 110 (ml / Kg) or more Σ targeted ones {(time load factor) ² × winding highest point temperature rise value}. Σ {(time load factor) ² × winding maximum point temperature rise value} and correlation between estimated average polymerization degree of insulation paper and actual measurement value obtained from correlation between insulation paper average polymerization degree and average error . It shows a correlation and error average of the average degree of polymerization of the estimated value and measured value of the insulating sheet obtained from the correlation between the amount of CO + CO ₂ and the average degree of polymerization of the insulating paper.

Claims (5)

Based on the amount of degradation products in the insulating oil of oil-filled electrical equipment, the accumulated load over time of the load applied to the oil-filled electrical equipment, and the data on the mechanical strength index of insulating paper For each predetermined range, create correlation data between the load integrated amount and the mechanical strength index of insulating paper,
Correlation between accumulated load and average polymerization degree used to estimate the degree of degradation of the target oil-filled electrical equipment based on the amount of degradation products measured from the insulation oil of the target oil-filled electrical equipment whose degree of degradation is estimated Select the data
Based on the correlation data between the selected load integrated amount and the mechanical strength index of insulating paper, an estimated value of the mechanical strength index of insulating paper is obtained from the measured load integrated amount of the target oil-filled electrical device, and the insulating paper A degradation degree estimation method for an oil-filled electrical device, wherein the degradation level of the target oil-filled electrical device is estimated based on an estimated value of a mechanical strength index. The method for estimating the degree of deterioration of an oil-filled electrical device according to claim 1, wherein the amount of the deterioration product is (CO + CO ₂ ), furfural, or acetone in insulating oil.   The method for estimating the degree of deterioration of oil-filled electrical equipment according to claim 1, wherein the mechanical strength index of the insulating paper is an average polymerization degree or tensile strength of the insulating paper.   The load integrated amount is obtained by multiplying the load factor of the oil-filled electrical equipment squared by the value obtained by multiplying the oil-filled electrical equipment winding maximum point temperature rise value over time, the load factor of the oil-filled electrical equipment 1.6 times the power of the oil-filled electrical equipment winding maximum point temperature rise, and the time-integrated sum of the oil-filled electrical equipment load factor squared The deterioration degree estimation method for an oil-filled electrical device according to claim 1, wherein the load factor of the oil-filled electrical device or a value obtained by multiplying the load factor of the oil-filled electrical device by 1.6 is integrated over time. Based on the amount of degradation products in the insulating oil of oil-filled electrical equipment, the accumulated load over time of the load applied to the oil-filled electrical equipment, and the mechanical strength index data of the insulation paper A correlation data storage unit that records correlation data between the load integrated amount and the mechanical strength index of the insulating paper, created for each predetermined range;
Based on the amount of degradation products measured from the insulation oil of the target oil-filled electrical equipment to estimate the degree of degradation, the correlation between the accumulated load used from the correlation data stored in the correlation data storage unit and the average degree of polymerization A correlation data selection unit for selecting data;
In the selection unit, based on the correlation data between the selected load integrated amount and the mechanical strength index of insulating paper, an estimated value of the mechanical strength index of insulating paper is obtained from the measured load integrated amount of oil-filled electrical equipment. An apparatus for estimating the degree of deterioration of an oil-filled electrical device, comprising: an estimated value calculation unit.

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