JP3440759B2 - Method and apparatus for diagnosing deterioration of electrical equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating medium such as mineral oil-based insulating oil or perfluorocarbon liquid used in oil-filled electrical equipment, or a cellulose-based insulating material, without particularly stopping the operation of the equipment in operation. The present invention relates to a deterioration diagnosis method and apparatus capable of nondestructively diagnosing the deterioration degree of a resin material of a resin mold insulation type electric device and an insulation material in a gas insulation type electric device such as SF ₆ .

[0002]

2. Description of the Related Art As a diagnostic method for estimating the deterioration degree and life of insulating oil and insulating paper of oil-filled electrical equipment, Japanese Patent Laid-Open No. 7-272939
As disclosed in Japanese Unexamined Patent Publication, furfural, which is a decomposition product of insulating paper, carbon monoxide, carbon dioxide, etc. are extracted from insulating oil, gas analysis is performed, and the gas generation amount and insulation A method of estimating the degree of deterioration from a correlation diagram with the residual degree of polymerization of paper has been proposed.

[0003]

In the above-mentioned prior art, since the amount of gas generated due to deterioration is very small, a special means for extracting it from the oil is required, or an evaluation device for gas analysis. It was not a simple diagnosis method because it was large.

Furthermore, it is the degree of deterioration of the insulating paper that governs the life of the equipment, but this is not directly diagnosed, but indirectly the decomposition products of the insulating paper dissolved in the insulating oil. Since it is a method of diagnosing, it has a problem that it is no longer possible to obtain an accurate measurement value of the total amount of decomposition products, for example, when the insulating oil is replaced with a medium-sized transformer or a small transformer. .

The object of the present invention is to solve the above-mentioned problems, and to prevent the operation of the equipment in operation from being stopped in particular, an insulating medium such as mineral oil-based insulating oil or perfluorocarbon liquid used in electric equipment, or a cellulose-based insulating medium. An object of the present invention is to provide a deterioration diagnosing method and apparatus capable of nondestructively diagnosing the degree of deterioration of an insulating material, a resin material of a resin mold insulating type electric device, and an insulating material in a gas insulating type electric device such as SF ₆ .

[0006]

Means for Solving the Problems As a result of studying the relationship between the degree of deterioration and the optical properties of various insulating materials such as insulating oil and insulating paper used in electric equipment and mold resin materials, Change in transmitted light intensity of insulating oil due to heat deterioration and insulating paper,
The present invention has been accomplished by finding a diagnostic method and a diagnostic device capable of determining the degree of deterioration from the change in reflected light intensity of a mold resin material. That is, the gist of the present invention is as follows.

(1) Irradiation light from at least two types of monochromatic light sources having different wavelengths is guided into an electric device by an irradiation optical fiber, and light emitted from the irradiation optical fiber is transmitted through an insulating medium having a transmission distance a. After that, the light is incident on and transmitted to a light receiving optical fiber guided to the outside of the electric device, is guided to a light quantity measuring section, and the light source intensity of the monochromatic light source is adjusted so that all the intensity in the light quantity measuring section becomes a constant value. After that, the irradiation light from the monochromatic light source is guided to the inside of the electric device by the irradiation optical fiber, the surface of the insulating material at the position of the transmission distance a / 2 is irradiated, and the reflected light from the surface of the insulating material is outside the electric device. It is guided to the light quantity measuring section using the light receiving optical fiber, and the reflection absorbance (A _λ ) at each wavelength is calculated by the formula (1) from the output value from the light quantity measuring section in the deterioration degree calculating section, and then, between two arbitrary wavelengths. Reflection of The light intensity difference (ΔA _λ ) or the reflection absorbance ratio (A _λ ′) is calculated by the equation (2) or the equation (3), and the deterioration degree of the measured material and the reflection absorbance difference or the reflection absorbance ratio are stored in advance. A deterioration diagnosis method and a diagnosis device for an electric device are characterized in that the deterioration degree is determined by comparing and calculating a relationship (master curve).

[0008]

## EQU5 ## A _λ = −log (R _λ / 100) (1) ΔA _λ = A _λ1 -A _λ2 (where λ1 <λ2) (2) A _λ ′ = A _λ1 / A _λ2 (where λ1 <λ2) (3) (The reflectance of the measured object at the wavelength λ (nm) is R
_λ (%)) The monochromatic light used as the light source has a wavelength of 650 to 13
A semiconductor laser (LD) or a light emitting diode (LED) having a peak wavelength of 10 nm is suitable because it is easily available, has a long life, and has stable performance. Especially 655, 66
0,670,780,800,820,830,85
LD, LED light sources of 0, 1300, 1310 nm and the like are suitable. In a light source having a wavelength other than the above range, the detector (light quantity measuring unit) may be in the overrange and the photometry may not be possible while the deterioration degree of the material to be measured is relatively small. If the material to be measured is originally a light-colored material, 65
800n such as 5,660, 670, 780, 800nm
It is more preferable to use light having a wavelength of m or less. on the other hand,
For materials that are originally colored,
780, 800, 820, 830, 850, 1300,
It is more preferable to use a wavelength in the near infrared region such as 1310 nm.

(2) Light emitted from a halogen lamp that emits white continuous light is guided through a spectroscope to the inside of an electric device through an optical fiber for irradiation, and light emitted from the optical fiber for irradiation is in an insulating medium having a transmission distance a. After being transmitted, the light is incident on and transmitted to a light receiving optical fiber that is guided to the outside of the electrical equipment, and is guided to the light quantity measurement unit. After measuring the wavelength dependence of the irradiation light intensity, the irradiation light is irradiated to the inside of the electrical equipment by the irradiation optical fiber. And irradiate the surface of the insulating material at the position of the transmission distance a / 2, and guide the reflected light from the surface of the insulating material to the light quantity measuring section using the light receiving optical fiber that guides it to the outside of the electric device. After calculating the reflection absorbance (A _λ ) at each wavelength from the output value from the light quantity measurement unit by the equation (1), the reflection absorbance difference (ΔA _λ ) or the reflection absorbance ratio (A _λ ′) between any two wavelengths is calculated. (2 Formula or (3) is calculated, and the measured value of the wavelength dependence of the irradiation light intensity is used to store the relationship between the deterioration degree of the material to be measured and the reflection absorbance difference or the reflection absorbance ratio (master curve ) Is compared and calculated to determine the degree of deterioration.

[0010]

(6) A _λ = −log (R _λ / 100) (1) ΔA _λ = A _λ1 −A _λ2 (where λ1 <λ2) (2) A _λ ′ = A _λ1 / A _λ2 (where λ1 <λ2) (3) (The reflectance of the measured object at the wavelength λ (nm) is R
_λ (%)) Generally, the change in the reflection absorbance spectrum due to the thermal deterioration of the organic material such as the insulating paper or the mold resin is represented by the change as shown in FIG. As shown in the figure, since the reflection absorbance significantly increases on the short wavelength side of the visible region with deterioration,
650 due to restrictions on the measurement range of the detector (light quantity measurement unit)
In the wavelength region of less than nm, it becomes substantially difficult to continuously measure the reflection absorbance of the material used until the end of the life of the device. This increase in reflection absorbance on the short wavelength side is mainly due to an increase in electron transition absorption loss due to the thermal oxidation deterioration reaction of the material.

Further, as the deterioration degree increases, the reflection absorbance A
_{Since λ} increases toward the shorter wavelength side, the reflection absorbance difference ΔA _λ (= A _λ1 −A _λ2 ) between any two wavelengths or the reflection absorbance ratio A _λ ′ (= A _λ1 / A _λ2 ) is also the same. To increase. Here, λ1 <λ2. For example, in FIG.
The reflection absorbance difference ΔA _λ between the wavelength λ1 (nm) and the wavelength λ2 (nm) is α1, α2, α
If 3, then the relationship α1>α2> α3 is established. The same applies to the reflection absorbance ratio A _λ ′.

The difference in reflection absorbance or the change in reflection absorbance ratio due to the heat deterioration has a correlation with the change in various physical properties of the material, and the physical properties of the material can be nondestructively measured by measuring these reflection absorbance parameters. Can diagnose decline. For example, the relationship between the average residual polymerization degree of the insulating paper of the oil-immersed transformer and the reflection absorbance difference is shown in FIG. 4, and it can be seen that there is a good correlation.

Further, as described in Japanese Patent Laid-Open No. 3-226651, the degree of deterioration is generally represented by a conversion time θ. By expressing it as the conversion time θ, it means that even if the materials have various thermal histories, if θ is the same, the degree of deterioration is the same. The conversion time θ (h) is defined by the equation (4).

[0014]

[Equation 7]

Here, ΔE is the apparent activation energy (J / mol) of thermal deterioration, R is the gas constant (J / K / mol), T
Is the absolute temperature (K) of heat deterioration, and t is the deterioration time (h). ΔE of resin, oil, etc. can be easily calculated by Arrhenius plotting the difference in reflection absorbance or the change in reflection absorbance ratio with respect to several kinds of deterioration temperatures.

Further, if the conversion time at the life point of the device using the insulating oil or the insulating paper which is obtained in advance is θ ₀ , the difference Δθ (= θ ₀ −
θ) is the converted time corresponding to the remaining life, and is a measure for determining the degree of deterioration. That is, the remaining life Δθ (h) is expressed by the equation (5).

[0017]

[Equation 8]

From the equation (5), if the operating temperature condition of the device after the time t is determined, the remaining life time Δt (= t ₀ -t) can be obtained.

When the deterioration degree of the insulating paper used in the oil-filled electrical equipment is to be diagnosed by the reflection absorbance difference (ΔA _λ ) or the reflection absorbance ratio (A _λ ′), there is no problem as long as the degree of deterioration is small. However, when the deterioration progresses and the insulating oil itself becomes colored, an accurate reflection absorbance value cannot be obtained due to the absorption of the insulating oil. Fig. 6 shows the insulating oil wavelengths of 660 nm and 8
An example of the master curve of the light transmission loss difference between 50 nm is shown, but the light transmission loss difference tends to exponentially increase as the deterioration progresses. In order to correct the increase in absorption due to the deterioration of the insulating oil, in the present invention, the transmitted light intensity at the distance a of the insulating oil is measured for each wavelength and the intensity correction between the wavelengths is performed. If the reflected light intensity of the insulating paper is measured at a distance a / 2 that is ½ of the transmitted optical path length at this time, the absorption of the insulating oil in the back and forth can be cancelled, and an accurate reflected light absorption value of the insulating paper can be obtained.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to examples.

(Embodiment 1) FIG. 1 is a schematic diagram showing an application form of a deterioration diagnosis device for an oil-filled electric device (transformer). Further, FIG. 7 shows a flowchart of the calculation for determining the degree of deterioration. In FIG. 1, the deterioration degree calculation unit 10 uses a notebook personal computer with a built-in hard disk unit. First, the amount of transmitted light of the insulating oil for each wavelength of the light source is measured, and the intensity of the transmitted light is corrected to a constant value. In this embodiment, an apparatus configuration using two wavelengths will be described. The monochromatic light having the peak wavelength λ1 = 660 nm generated from the light source section 8 containing the two types of LED light sources is guided to the irradiation optical fiber 6, reaches the probe 5 shown in FIG. 2, and passes through the half mirror 11. After doing
It penetrates through the insulating oil at the distance a. This transmitted light is received by the light receiving unit 13.
After passing through, the light is transmitted to the light quantity measuring section 9 through the light receiving optical fiber 7. The light quantity measuring unit 9 uses an optical power meter with a built-in photodiode. Similarly, the same operation is performed using the monochromatic light having the peak wavelength λ2 = 850 nm generated from the light source unit 8, and the light intensity adjustment dial of the light source unit is adjusted so that the transmitted light intensities of λ1 and λ2 are equal. In this measurement, this base value was adjusted to 600 nW. By performing this operation, it is possible to correct the influence of light absorption due to the deterioration of the insulating oil on the deterioration diagnosis of the insulating paper. next,
The amount of reflected light from the insulating paper, which essentially controls the life, is measured. The monochromatic light having the peak wavelength λ1 = 660 nm from the light source unit 8 is guided to the irradiation optical fiber 6 by the same operation, passes through the probe 5, and is irradiated onto the surface of the insulating paper on the coil 2. The reflected light measuring portion side of the probe 5 has a shield ring structure for blocking external stray light as shown in FIG. Further, as shown in FIG. 2, it is designed so that the distance of 1/2 of the optical path length for measuring the transmitted light intensity can be maintained.
The reflected light from the surface of the insulating paper of the coil 2 is sent to the light quantity measurement unit 9 via the light receiving optical fiber 7.
The reflected light amount I ₁ ′ is measured and the deterioration degree calculation unit 10 outputs the result I ₁ ′.
Is output. In the deterioration degree calculation unit 10, the reflectance R ₆₆₀ (= 100 × I ₁ ′ / I ₀ , I ₀ = 60 at ₆₆₀ nm is used.
0) is calculated and stored in the memory. Similarly, the same operation is performed using the monochromatic light having the peak wavelength λ2 = 850 nm, and the deterioration degree calculation unit 10 calculates the reflectance R ₈₅₀ (= 100 × I ₂ ′ / I ₀ , I ₀ = 600) at ₈₅₀ nm. Calculated and stored in memory. In this way, 66
Since the reflectance at 0,850 nm is obtained, the deterioration degree calculator 10 calculates the difference in reflection absorbance between two wavelengths ΔA _λ (=
A _λ1 -A _λ2 ) or reflection absorbance ratio A _λ '(= A _λ1
/ A _λ2 ) is required. In the hard disk unit, a reflection absorbance difference or a reflection absorbance ratio corresponding to the degree of deterioration as shown in FIGS. From the stored function value and the actually measured reflection absorbance difference or the reflection absorbance ratio value, the deterioration degree calculating unit 10 performs a comparison calculation to determine the deterioration degree, and outputs the measurement result to an external printer (not shown) or the like.

In this embodiment, the deterioration degree measuring apparatus for materials using two wavelengths has been described, but the deterioration degree can be judged by operating the measuring apparatus similarly for three wavelengths and using a master curve for three wavelengths. . Further, the light may be combined and simultaneously irradiated without time-division irradiation. In this case, it is effective to apply a filter on the detector (light quantity measurement section) side. This device can be applied both for the purpose of continuous monitoring online and for the purpose of carrying out inspection operation while carrying.

(Embodiment 2) As in Embodiment 1, FIG.
An example in which the deterioration diagnosis is applied to the transformer using the perfluorocarbon liquid 14 as the insulating medium shown in FIG. First, the amount of transmitted light of the perfluorocarbon liquid with respect to each light source wavelength is measured, and the transmitted light intensity is corrected so as to be a constant value. The monochromatic light having the peak wavelength λ1 = 780 nm generated from the light source unit 8 incorporating the two types of LD light sources is guided to the irradiation optical fiber 6, reaches the probe 5 shown in FIG. 2, and passes through the half mirror 11. After that, it permeates through the perfluorocarbon liquid at a distance a. The transmitted light passes through the light receiving section 13 and then is transmitted to the light quantity measuring section 9 through the light receiving optical fiber 7. Similarly, the same operation is performed using the monochromatic light having the peak wavelength λ2 = 1310 nm generated from the light source unit 8, and the light intensity adjustment dial of the light source unit is adjusted so that the transmitted light intensities of λ1 and λ2 are equal. In this measurement, this base value was adjusted to 1.0 μW. Next, the reflected light amount of the insulating paper is measured. Peak wavelength λ1 = 780n from the light source unit 8
The monochromatic light of m is irradiated with the optical fiber 6 by the same operation.
And is irradiated onto the surface of the insulating paper on the coil 2 through the probe 5. The reflected light from the surface of the insulating paper of the coil 2 is sent to the light quantity measuring unit 9 through the light receiving optical fiber 7, the reflected light quantity I ₁ ′ is measured, and the deterioration degree calculation unit 10 outputs the result I ₁ ′. Is output. In the deterioration degree calculation unit 10, the reflectance R ₇₈₀ (= 100 × I ₁ ′) at ₇₈₀ nm is obtained.
/ I ₀ , I ₀ = 1.0) is calculated and stored in the memory. Similarly, the same operation is performed using the monochromatic light with the peak wavelength λ2 = 1310 nm, and the reflectance R ₁₃₁₀ (= 100 ×
I ₂ ′ / I ₀ , I ₀ = 1.0) is calculated and stored in the memory. In this way, since the reflectances at 780 and 1310 nm are obtained, the deterioration calculating section 10 reflects the difference in reflection absorbance between two wavelengths ΔA _λ (= A _λ1 −A _λ2 ) or the reflection absorbance ratio A _λ ′ (= A _λ1). / A _λ2 ) is required.
The reflection absorbance difference or the reflection absorbance ratio corresponding to the deterioration degree as shown in FIGS. 5 and 9 is stored in advance in the hard disk unit as a master curve, and is output to the deterioration degree calculation unit 10. The deterioration degree calculation unit 10 compares the stored function value with the actually measured reflection absorption difference or the reflection absorption ratio value to determine the deterioration degree.

(Third Embodiment) Similar to the first and second embodiments,
An example is shown in which deterioration diagnosis is applied to the transformer using SF ₆ gas 15 as the insulating medium shown in FIG. 10. First, the amount of transmitted light of SF ₆ gas for each light source wavelength is measured,
The transmitted light intensity is corrected to a constant value. 2 types of L
Peak wavelength λ1 generated from the light source unit 8 having a built-in D light source
The monochromatic light of 780 nm is guided to the irradiation optical fiber 6, reaches the inside of the probe 5 shown in FIG. 2, passes through the half mirror 11, and then passes through the SF ₆ gas at the distance a. The transmitted light passes through the light receiving section 13 and then is transmitted to the light quantity measuring section 9 through the light receiving optical fiber 7. Similarly, the same operation is performed using the monochromatic light having the peak wavelength λ2 = 1310 nm generated from the light source unit 8, and the light intensity adjustment dial of the light source unit is adjusted so that the transmitted light intensities of λ1 and λ2 are equal. In this measurement, this base value was adjusted to 1.5 μW.
Next, the reflected light amount of the insulating paper is measured. The monochromatic light with the peak wavelength λ1 = 780 nm from the light source unit 8 is guided to the irradiation optical fiber 6 by the same operation, passes through the probe 5, and is irradiated onto the surface of the insulating paper on the coil 2. The reflected light from the surface of the insulating paper of the coil 2 is passed through the light receiving optical fiber 7,
The transmitted light is sent to the light quantity measurement unit 9, the reflected light quantity I ₁ ′ is measured, and the result I ₁ ′ is output to the deterioration degree calculation unit 10.
In the deterioration degree calculation unit 10, the reflectance R at 780 nm
₇₈₀ (= 100 × I ₁ ′ / I ₀ , I ₀ = 1.5) is calculated and stored in the memory. Similarly, the peak wavelength λ2 = 13
The same operation is performed using monochromatic light of 10 nm, and the reflectance R ₁₃₁₀ (= 1 at ₁₃₁₀ nm in the deterioration degree calculation unit 10
00 × I ₂ ′ / I ₀ , I ₀ = 1.5) is calculated and stored in the memory. In this way, since the reflectances at 780 and 1310 nm are obtained, the deterioration degree calculator 10 reflects the difference in reflection absorbance between two wavelengths ΔA _λ (= A _λ1 −A _λ2 ) or the reflection absorbance ratio A _λ ′ (= A _λ1). / A _λ2 ) is required. The reflection absorbance difference or the reflection absorbance ratio corresponding to the deterioration degree as shown in FIGS. 5 and 9 is stored in advance in the hard disk unit as a master curve, and is output to the deterioration degree calculation unit 10. The deterioration degree calculation unit 10 compares the stored function value with the actually measured reflection absorption difference or the reflection absorption ratio value to determine the deterioration degree.

(Embodiment 4) In the same manner as in Embodiments 1 to 3,
An example in which deterioration diagnosis is applied to the resin mold type dry transformer shown in FIG. 11 is shown. First, the amount of transmitted light for each light source wavelength is measured, and the transmitted light intensity is corrected to a constant value. The medium in this case is air. The monochromatic light having the peak wavelength λ1 = 660 nm generated from the light source section 8 incorporating the two types of LED light sources is the irradiation optical fiber 6
2 to reach the inside of the probe 5 shown in FIG. 2, pass through the half mirror 11, and then pass through the gap portion of the distance a. The transmitted light passes through the light receiving section 13 and then is transmitted to the light quantity measuring section 9 through the light receiving optical fiber 7. Similarly, the same operation is performed using the monochromatic light having the peak wavelength λ2 = 850 nm generated from the light source unit 8, and the light intensity adjustment dial of the light source unit is adjusted so that the transmitted light intensities of λ1 and λ2 are equal. In this measurement, this base value was adjusted to 800 nW.
Next, the amount of reflected light of the epoxy mold resin 16 is measured. The monochromatic light having the peak wavelength λ1 = 660 nm from the light source unit 8 is guided to the irradiation optical fiber 6 by the same operation, passes through the probe 5, and is irradiated onto the surface of the epoxy mold resin on the coil 2. The reflected light from the epoxy mold resin surface of the coil 2 is sent to the light quantity measuring unit 9 through the light receiving optical fiber 7, the reflected light quantity I ₁ ′ is measured, and the result I ₁ is sent to the deterioration degree calculating unit 10. ′ Is output. In the deterioration degree calculation unit 10, the reflectance R ₆₆₀ (= 100 × I ₁ ′ / I ₀ , I ₀ = 800) at ₆₆₀ nm is calculated and stored in the memory. Similarly, the same operation is performed using monochromatic light having a peak wavelength λ2 = 850 nm,
In the deterioration degree calculation unit 10, the reflectance R at 850 nm
₈₅₀ (= 100 × I ₂ ′ / I ₀ , I ₀ = 800) is calculated and stored in the memory. In this way, 660,85
Since the reflectance at 0 nm can be obtained, the deterioration degree calculation unit 1
At 0, the difference in reflection absorbance between the two wavelengths ΔA _λ (= A _λ1 −
A _λ2 ) or reflection absorbance ratio A _λ '(= A _λ1 /
A _λ2 ) is required. In the hard disk unit,
The reflection absorbance difference or the reflection absorbance ratio corresponding to the deterioration degree as shown in FIGS. 5 and 9 is stored in advance as a master curve and is output to the deterioration degree calculation unit 10. The deterioration degree calculation unit 10 compares the stored function value with the actually measured reflection absorption difference or the reflection absorption ratio value to determine the deterioration degree.

(Fifth Embodiment) Similar to the first embodiment, an application example of the deterioration diagnosing device to the oil-filled transformer in the case where the light source unit 8 uses a halogen lamp for irradiating white continuous light will be described.
First, the wavelength dependence of insulating oil is measured. Continuous light from the light source unit 8 is guided to the irradiation optical fiber 6 through the spectroscope, reaches the probe 5 shown in FIG. 2, passes through the half mirror 11, and then passes through the insulating oil at the distance a. To Penetrate. This transmitted light passes through the light receiving unit 13 and then is received by the light receiving optical fiber 7.
And is transmitted to the light amount measuring unit 9 to obtain the reference light amount I _{λ at} each wavelength λ. The measurement range of the wavelength dependence is not particularly limited, but a range of 400 to 1500 nm is sufficient. Next, the wavelength dependence of the reflected light amount of the insulating paper is measured. Continuous light from the light source unit 8 is guided to the irradiation optical fiber 6 by the same operation, passes through the probe 5 and the coil 2
The surface of the upper insulating paper is irradiated. The reflected light from the surface of the insulating paper of the coil 2 is sent to the light quantity measuring unit 9 via the light receiving optical fiber 7, the reflected light quantity I _λ ′ is measured, and the deterioration degree calculation unit 10 outputs the result I _λ ′. Is output. In the deterioration degree calculation unit 10, the reflectance R _λ (= 10 at each wavelength)
Since 0 × I _λ ′ / I _λ ) is calculated and stored in the memory, the deterioration calculating section 10 reflects the difference ΔA _λ (= A _λ1 −A _λ2 ) in reflection absorbance between two arbitrary wavelengths or the reflection absorbance ratio. A _λ '(= A _λ1 / A _λ2 ) is obtained. In the hard disk unit, the reflection absorbance difference or the reflection absorbance ratio corresponding to the deterioration degree as shown in FIGS. 5 and 9 is stored in advance as a master curve, and the deterioration degree calculation unit 10
Output to. From the stored function value and the actually measured reflection absorbance difference or the reflection absorbance ratio value, the deterioration degree calculating unit 10 performs a comparison calculation to determine the deterioration degree, and outputs the measurement result to an external printer (not shown) or the like.

(Sixth Embodiment) Similar to the fifth embodiment, an application example of the deterioration diagnosing device to the perfluorocarbon liquid-immersed transformer in the case where the halogen lamp for irradiating the white continuous light is used for the light source section 8 will be described. First, the wavelength dependence of the perfluorocarbon liquid is measured. Continuous light from the light source unit 8 is guided to the irradiation optical fiber 6 through the spectroscope, reaches the inside of the probe 5 shown in FIG. 2, passes through the half mirror 11, and is then in the perfluorocarbon liquid at a distance a. Through.
The transmitted light passes through the light receiving section 13 and then is transmitted to the light quantity measuring section 9 through the light receiving optical fiber 7 to obtain the reference light quantity I _{λ at} each wavelength λ. The measurement range of the wavelength dependence is not particularly limited, but a range of 400 to 1500 nm is sufficient. Next, the wavelength dependence of the reflected light amount of the insulating paper is measured. Continuous light from the light source unit 8 is guided to the irradiation optical fiber 6 by the same operation, passes through the probe 5, and is irradiated onto the surface of the insulating paper on the coil 2. The reflected light from the surface of the insulating paper of the coil 2 is passed through the light receiving optical fiber 7,
The transmitted light is sent to the light quantity measurement unit 9, the reflected light quantity I _λ ′ is measured, and the result I _λ ′ is output to the deterioration degree calculation unit 10.
In the deterioration degree calculator 10, the reflectance R _λ (=
Since 100 × I _λ ′ / I _λ ) is calculated and stored in the memory, the deterioration degree calculator 10 reflects the difference in reflection absorbance between two arbitrary wavelengths ΔA _λ (= A _λ1 −A _λ2 ) or the reflection absorbance ratio. A _λ '(= A _λ1 / A _λ2 ) is obtained. The reflection absorbance difference or the reflection absorbance ratio corresponding to the deterioration degree as shown in FIGS. 5 and 9 is stored in advance in the hard disk unit as a master curve, and is output to the deterioration degree calculation unit 10. From the stored function value and the measured reflection absorbance difference or the reflection absorbance ratio value, the deterioration degree calculation unit 10
And the degree of deterioration is determined by comparison calculation.

(Embodiment 7) In the same manner as in Embodiments 5 and 6,
An example of application of the deterioration diagnosis device to the SF ₆ gas transformer when a halogen lamp that emits white continuous light is used for the light source unit 8 will be shown. First, the wavelength dependence of SF ₆ gas is measured.
Continuous light from the light source unit 8 is guided through the spectroscope to the irradiation optical fiber 6, reaches the inside of the probe 5 shown in FIG. 2, passes through the half mirror 11, and then in the SF ₆ gas at a distance a. Through. The transmitted light passes through the light receiving section 13 and then is transmitted to the light quantity measuring section 9 through the light receiving optical fiber 7 to obtain the reference light quantity I _{λ at} each wavelength λ. The measurement range of the wavelength dependence is not particularly limited, but 400 to 1
A region of 500 nm is sufficient. Next, the wavelength dependence of the reflected light amount of the insulating paper is measured. Continuous light from the light source unit 8 is
By the same operation, it is guided to the irradiation optical fiber 6, passes through the probe 5, and is irradiated onto the surface of the insulating paper on the coil 2.
The reflected light from the surface of the insulating paper of the coil 2 is sent to the light quantity measurement unit 9 via the light receiving optical fiber 7.
The amount of reflected light I _λ ′ is measured and the result I _λ ′ is output to the deterioration degree calculator 10. In the deterioration degree calculation unit 10, the reflectance R _λ (= 100 × I _λ ′ / I _λ ) at each wavelength is calculated and stored in the memory, so that the deterioration degree calculation unit 10 reflects between two arbitrary wavelengths. Absorbance difference ΔA _λ (= A _λ1 −
A _λ2 ) or reflection absorbance ratio A _λ '(= A _λ1 / A _λ2 )
Is required. The reflection absorbance difference or the reflection absorbance ratio corresponding to the deterioration degree as shown in FIGS. 5 and 9 is stored in advance in the hard disk unit as a master curve, and is output to the deterioration degree calculation unit 10. The deterioration degree calculation unit 10 compares the stored function value with the actually measured reflection absorption difference or the reflection absorption ratio value to determine the deterioration degree.

(Embodiment 8) In the same manner as in Embodiments 5-7,
An example of application of the deterioration diagnosing device to a resin-mold dry transformer in which a halogen lamp that emits white continuous light is used as the light source unit 8 will be described. First, the wavelength dependence of the light source is measured. Continuous light from the light source unit 8 is guided to the irradiation optical fiber 6 via the spectroscope, reaches the inside of the probe 5 shown in FIG. 2, passes through the half mirror 11, and then passes through the gap portion at the distance a. To do. The transmitted light passes through the light receiving section 13 and then is transmitted to the light quantity measuring section 9 through the light receiving optical fiber 7 to obtain the reference light quantity I _{λ at} each wavelength λ. The measurement range of the wavelength dependence is not particularly limited, but 400 to 1
A region of 500 nm is sufficient. Next, the wavelength dependence of the amount of reflected light of the epoxy mold resin 16 is measured. The continuous light from the light source unit 8 is guided to the irradiation optical fiber 6 by the same operation, passes through the probe 5, and is irradiated onto the surface of the epoxy mold resin on the coil 2. Optical fiber 7 for receiving the light reflected from the epoxy mold resin surface of coil 2
The transmitted light is sent to the light amount measuring unit 9 via the, and the reflected light amount I _λ ′ is measured, and the result I _λ ′ is output to the deterioration degree calculating unit 10. In the deterioration degree calculation unit 10, the reflectance R _λ (= 100 × I _λ ′ / I _λ ) at each wavelength is calculated and stored in the memory, so that the deterioration degree calculation unit 10 reflects between two arbitrary wavelengths. Absorbance difference ΔA _λ (= A _λ1 −A _λ2 )
Alternatively, the reflection absorbance ratio A _λ ′ (= A _λ1 / A _λ2 ) can be obtained. In the hard disk unit, a reflection absorbance difference or a reflection absorbance ratio corresponding to the degree of deterioration as shown in FIGS. 5 and 9 is stored in advance as a master curve.
It is output to the deterioration degree calculation unit 10. The deterioration degree calculation unit 10 compares the stored function value with the actually measured reflection absorption difference or the reflection absorption ratio value to determine the deterioration degree.

(Embodiment 9) An example of performing the deterioration diagnosis with the device configuration of Embodiment 1 using the difference in the light transmission loss between two wavelengths of insulating oil as a parameter will be described. First, the amount of transmitted light in air for each light source wavelength is measured. Two types of LED light sources (λ1 = 660 nm, λ2 = 850n)
m) was used. The reference amount of light at each wavelength when transmitted through the gap of distance a (cm) is measured, and this is I
_{Let λ 1} and I _{λ 2} . Next, similarly, the amount of transmitted light in the insulating oil is measured. The amount of transmitted light I _λ1 ′ of the insulating oil at 660 nm was measured, and the result I was calculated by the deterioration degree calculation unit 10.
_λ1 'is output. In the deterioration degree calculation unit 10, 660n
Light transmission loss at m α _λ1 (= -10 / a × log
(I _λ1 ′ / I _λ1 ), unit dB / cm) is calculated and stored in the memory. Similarly, the same operation is performed by using monochromatic light of 850 nm, and the deterioration degree calculation unit 10 performs 850
light transmission loss α nm _λ2 (= -10 / a × log (I
_λ2 '/ I _λ2 ), unit dB / cm) is calculated and stored in the memory. In this way, 660nm, 850nm
Since the light transmission loss in
Difference in optical transmission loss between two wavelengths at Δα _λ (= α _λ1 −α
_{λ 2} ) is required. In the hard disk unit, the light transmission loss difference corresponding to the deterioration degree as shown in FIG. 6 is stored in advance as a master curve.
Output to 0. The deterioration degree can be determined by performing a comparison calculation in the deterioration degree calculation unit 10 from the stored function value and the value of the measured optical transmission loss difference of the insulating oil.

(Embodiment 10) An example of performing a deterioration diagnosis with the device configuration of Embodiment 5 using the difference in light transmission loss between two wavelengths of insulating oil as a parameter will be described. First, the amount of transmitted light in air for white continuous light is measured. A halogen lamp was used as the light source. The amount of reference light at each wavelength when transmitted through the gap portion at the distance a (cm) is measured, and is referred to as I _λ . The range of the wavelength λ is not particularly limited, but a range of 400 to 1500 nm is sufficient.
Next, the amount of transmitted light at each wavelength in the insulating oil is measured. The amount of transmitted light I _λ ′ of insulating oil at the wavelength λ is measured, and the result I _λ ′ is output to the deterioration degree calculator 10. The deterioration degree calculator 10 calculates the light transmission loss α at the wavelength λ.
_λ (= −10 / a × log (I _λ ′ / I _λ ), unit dB / c
m) is calculated and stored in memory. In this way, since the light transmission loss at each wavelength is obtained, the deterioration degree calculation unit 10 calculates the light transmission loss difference Δα between two arbitrary wavelengths.
_λ (= α _λ1 −α _λ2 ) is obtained. In the hard disk unit, the light transmission loss difference corresponding to the degree of deterioration as shown in FIG. 6 is stored in advance as a master curve.
It is output to the deterioration degree calculation unit 10. From the stored function value and the value of the measured optical transmission loss difference of the insulating oil, the deterioration degree calculation unit 10
The deterioration degree can be determined by performing a comparison calculation with.

[0032]

According to the present invention, an insulating medium such as a mineral oil-based insulating oil, a perfluorocarbon liquid or the like used in an oil-filled electric device or a cellulose-based insulating material can be used without particularly stopping the operation of the device in operation. It is possible to obtain a deterioration diagnosing method and apparatus capable of nondestructively diagnosing the degree of deterioration of the resin material of the resin mold insulation type electric equipment and the insulation material of the gas insulation type electric equipment such as SF ₆ .

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an application form of a deterioration diagnosis device for an oil-filled electrical device (transformer).

FIG. 2 is a schematic cross-sectional view of a probe.

FIG. 3 is a conceptual diagram of a change in reflection absorbance spectrum of a material.

FIG. 4 is an example of a relationship diagram between an average residual polymerization degree of insulating paper and a reflection absorbance difference.

FIG. 5 is an example of a reflection / absorption difference master curve of insulating paper, which serves as a reference for deterioration degree determination.

FIG. 6 is an example of a master curve of light transmission loss difference of insulating oil.

FIG. 7 is a flowchart of calculation for deterioration degree determination.

FIG. 8 is a schematic diagram showing a form of application to a perfluorocarbon liquid-immersed transformer.

FIG. 9 shows an example of a reflection / absorption ratio master curve of insulating paper which serves as a criterion for determining the degree of deterioration.

FIG. 10 is a schematic diagram showing an application form to an SF ₆ gas transformer.

FIG. 11 is a schematic diagram showing a form of application to a resin mold type dry transformer.

[Explanation of symbols]

1 ... Oil-filled electrical equipment (transformer), 2 ... Coil, 3 ... Iron core,
4 ... Insulating oil, 5 ... Probe, 6 ... Irradiation optical fiber,
7 ... Optical fiber for receiving light, 8 ... Light source part, 9 ... Light quantity measuring part, 10 ... Degradation degree calculating part, 11 ... Half mirror, 12 ...
Stray light shielding ring, 13 ... Light receiving part, 14 ... Perfluorocarbon liquid, 15 ... SF ₆ gas, 16 ... Epoxy mold resin.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigekatsu Sato 1-1-1 Kokubun-cho, Hitachi-shi, Ibaraki, Ltd. Kokubun factory, Hitachi, Ltd. (56) Reference JP-A-9-7840 (JP, A) JP-A-3-226653 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01F 27/00

Claims (6)

(57) [Claims] 1. Irradiation light from at least two types of monochromatic light sources having different wavelengths is guided inside an electric device by an irradiation optical fiber, and light emitted from the irradiation optical fiber has a transmission distance a.
After passing through the insulating medium, it enters and transmits to the light receiving optical fiber that is guided to the outside of the electrical equipment, and is guided to the light quantity measurement unit.
After adjusting the light intensity of the light source intensity of the monochromatic light source so that all the intensities in the light amount measuring section are constant values, the irradiation light from the monochromatic light source is guided to the inside of an electric device by an irradiation optical fiber,
Irradiate the surface of the insulating material at the position of the transmission distance a / 2, and guide the reflected light from the surface of the insulating material to the light quantity measuring section using a light receiving optical fiber that guides the light to the outside of the electric device, and measure the light quantity in the deterioration degree calculating section. After calculating the reflection absorbance (A _λ ) at each wavelength from the output value from the section by the formula (1), the reflection absorbance difference (ΔA _λ ) or the reflection absorbance ratio (A _λ ′) between any two wavelengths is calculated as (2). Formula or (3) is calculated, and the degree of deterioration is determined by comparing and calculating the relationship (master curve) between the degree of deterioration of the material to be measured and the reflection absorbance difference or the reflection absorbance ratio, which is stored in advance. A method for diagnosing deterioration of electrical equipment. ## EQU1 ## A _λ = −log (R _λ / 100) (1) ΔA _λ = A _λ1 −A _λ2 (where λ1 <λ2) (2) A _λ ′ = A _λ1 / A _λ2 (where λ1 <λ2) (3) (The reflectance of the measured object at the wavelength λ (nm) is R
_λ (%)) 2. The deterioration diagnosing method for an electric device according to claim 1, wherein a semiconductor laser or a light emitting diode having a peak wavelength of 650 nm or more and 1310 nm or less is used as the monochromatic light source. 3. Light emitted from a halogen lamp that emits white continuous light is guided through a spectroscope to the inside of electrical equipment by an optical fiber for irradiation, and light emitted from the optical fiber for irradiation passes through an insulating medium having a transmission distance a. After passing through the optical fiber for light reception, which is guided to the outside of the electrical equipment, is transmitted, is guided to the light quantity measurement unit, and after measuring the wavelength dependence of the intensity of the irradiation light, the irradiation light is transmitted to the inside of the electrical equipment by the optical fiber for irradiation. The light is guided to the surface of the insulating material at the position of the transmission distance a / 2, and the reflected light from the surface of the insulating material is guided to the light quantity measuring section using a light receiving optical fiber for guiding the light to the outside of the electric device. After calculating the reflection absorbance (A _λ ) at each wavelength from the output value from the light quantity measurement unit by the equation (1), the reflection absorbance difference (ΔA _λ ) or the reflection absorbance ratio (A _λ ′) between any two wavelengths can be calculated by 2) Expression The relationship (master curve) between the deterioration degree of the material to be measured and the reflection absorbance difference or the reflection absorbance ratio, which is stored in advance, is calculated using the equation (3) and the measured value of the wavelength dependence of the irradiation light intensity. A deterioration diagnosis method for an electric device, characterized in that a deterioration degree is determined by performing a comparison calculation. (2) A _λ = −log (R _λ / 100) (1) ΔA _λ = A _λ1 −A _λ2 (where λ1 <λ2) (2) A _λ ′ = A _λ1 / A _λ2 (where λ1 <λ2) (3) (The reflectance of the measured object at the wavelength λ (nm) is R
_λ (%)) 4. A light source section comprising at least two kinds of monochromatic light sources having different wavelengths, an irradiation optical fiber for guiding the irradiation light from the light source section into an electric device, and an irradiation light guided by the irradiation optical fiber. After passing through an insulating medium having a transmission distance a, a light receiving optical fiber for guiding the transmitted light to the outside of the electric device, a light amount measuring unit for measuring the intensity of the transmitted light guided by the light receiving optical fiber, and the monochromatic light source. After adjusting the light intensity of the light source so that all the transmitted light intensities are constant, the irradiation light from the light source is guided to the inside of the electric device by the irradiation optical fiber, and the insulating material is located at the transmission distance a / 2. The surface is irradiated, and the reflected light from the surface of the insulating material is guided to the light quantity measuring section using the light receiving optical fiber, and the reflection absorbance (A _λ ) at each wavelength is _calculated by the formula (1) from the output value from the light quantity measuring section. After calculation, Reflection absorbance difference between two desired wavelengths (Δ
A _λ ) or the reflection absorbance ratio (A _λ ′) is calculated by the equation (2) or the equation (3), and the relationship between the deterioration degree of the material to be measured and the reflection absorbance difference or the reflection absorbance ratio stored in advance (master) A deterioration diagnosis apparatus for an electric device, comprising: a deterioration degree calculation unit that determines a deterioration degree by comparing and calculating a curve). ## EQU3 ## A _λ = −log (R _λ / 100) (1) ΔA _λ = A _λ1 -A _λ2 (where λ1 <λ2) (2) A _λ ′ = A _λ1 / A _λ2 (where λ1 <λ2) (3) (The reflectance of the measured object at the wavelength λ (nm) is R
_λ (%)) 5. The deterioration diagnostic apparatus for electric equipment according to claim 8, wherein a semiconductor laser or a light emitting diode having a peak wavelength of 650 nm or more and 1310 nm or less is used as the monochromatic light source. 6. A light source section comprising a halogen lamp for irradiating white continuous light, an irradiation optical fiber for guiding the irradiation light from the light source section into an electric device through a spectroscope, and an irradiation optical fiber. A light receiving optical fiber that guides the transmitted light to the outside of the electric device after the irradiation light has passed through an insulating medium having a transmission distance a, a light amount measuring unit that measures the intensity of the transmitted light guided by the light receiving optical fiber, and the irradiation After measuring the wavelength dependence of the light intensity, the irradiation light is guided to the inside of the electric device by the irradiation optical fiber, and the surface of the insulating material at the position of the transmission distance a / 2 is irradiated with the reflected light from the surface of the insulating material. It is guided to the light quantity measuring section using the light receiving optical fiber, and the reflection absorbance at each wavelength is determined from the output value from the light quantity measuring section.
After calculating (A _λ ) by the equation (1), the reflection absorbance difference (ΔA _λ ) between two arbitrary wavelengths or the reflection absorbance ratio (A _λ ′) is calculated by the equation (2) or the equation (3). Using the measured value of the wavelength dependence of the irradiation light intensity, the degree of deterioration is determined by comparing and calculating the relationship (master curve) between the degree of deterioration of the material to be measured and the reflection absorbance difference or the reflection absorbance ratio, which is stored in advance. And a deterioration degree calculating section for performing deterioration diagnosis apparatus for electric equipment. (4) A _λ = −log (R _λ / 100) (1) ΔA _λ = A _λ1 −A _λ2 (where λ1 <λ2) (2) A _λ ′ = A _λ1 / A _λ2 (where λ1 <λ2) (3) (The reflectance of the measured object at the wavelength λ (nm) is R
_λ (%))