JP7380482B2 - Insulation deterioration diagnosis device - Google Patents

Description

The present invention relates to a technique for diagnosing insulation deterioration of a rotating machine.

In recent years, technology has been proposed to detect signs of insulation deterioration in the stator coils by detecting partial discharges generated from the stator coils of high-voltage rotating machines and the gas generated due to these partial discharges. (For example, Patent Documents 1 to 3).

Japanese Patent Application Publication No. 2002-267712 JP2012-007924A Japanese Patent Application Publication No. 2019-032184

Diagnosis of insulation deterioration in high-pressure rotating machines such as those for turbines and water turbines has been performed offline (while they are stopped), but since infrastructure equipment cannot be stopped easily, it is desirable to create a method that can detect abnormalities in rotating machines even during operation. It is rare.

In addition, because high-voltage rotating machines have insulation systems that tolerate partial discharges, in addition to direct ground faults and short circuits caused by partial discharges, corrosive gas generated by partial discharges can also cause damage to structures inside the rotating machines. There are also accidents associated with this. Therefore, there is a need for a technology to diagnose how the occurrence of partial discharges is changing and a technology to diagnose how the situation of corrosive gas generated by partial discharge is changing. .

Regarding partial discharge detection, there is a partial discharge measuring means sold by, for example, IRIS Power. Standards related to this device are summarized in IEC TS60034-27-2. However, there is no example of an implementation of an insulation deterioration diagnostic device that also uses a means for measuring gas generated due to partial discharge.

As a device for solving this problem, a technique for diagnosing insulation deterioration from a PD (partial discharge) pattern and a pattern of generated gases (particularly ozone, nitrogen oxides, and ammonia) can be considered.

In particular, discharges caused by ozone generation include slot discharges, discharges due to abnormalities in straight sections outside the grooves, and discharges between adjacent coils at the coil ends. The problem is that it cannot be determined based on measurements alone.

For the reasons described above, in the insulation deterioration diagnosis apparatus, it is a problem to determine the amount of ozone generated from the partial discharge pattern.

The present invention has been devised in view of the above-mentioned conventional problems, and one aspect thereof is an insulation deterioration diagnosis device for a rotating machine, comprising: partial discharge detection means for detecting partial discharge in the rotating machine; temperature detection means for measuring the temperature of a stator of the rotating machine; water vapor amount acquisition means for measuring the dew point or temperature/humidity of cooling gas inside the rotating machine; and ozone concentration and ozone flow rate inside the rotating machine. gas measuring means for measuring, partial discharge pattern acquisition means for acquiring a partial discharge pattern of phase and discharge charge amount from the detected partial discharge, and integration for acquiring an integrated discharge charge amount related to slot discharge from the partial discharge pattern. Data processing that performs a discharge charge amount acquisition process, a discharge power amount acquisition process that calculates a discharge power amount from the integrated discharge power amount, and an ozone generation amount acquisition process that calculates a first ozone generation amount based on the discharge power amount. It is characterized by comprising a storage means.

In one embodiment, the ozone generation amount obtaining process calculates a second ozone generation amount based on the ozone concentration and the ozone flow rate, and calculates the second ozone generation amount based on the difference between the second ozone generation amount and the first ozone generation amount. The method is characterized in that the amount of third ozone generated due to discharge occurring other than discharge is determined.

In one embodiment, the integrated discharge charge amount acquisition process extracts a first phase of positive polarity and the steepest change from the partial discharge pattern, and extracts a first phase of positive polarity and a steepest change, The second phase of the change in negative polarity is extracted, the change in the first phase and the change in the second phase are compared, and if the change in the first phase is larger, it is determined that it is a slot discharge and the first phase is changed. Obtain the cumulative discharge charge amount at The fourth phase is extracted, the change in the third phase is compared with the change in the fourth phase, and if the change in the third phase is larger, it is determined that it is a slot discharge, and the integrated discharge charge amount in the third phase is determined. , extract a fifth phase of positive polarity change that is -240° out of phase with the first phase, and extract a sixth phase of negative polarity change that is 180° out of phase with respect to the fifth phase. and comparing the change in the fifth phase with the change in the sixth phase, and if the change in the fifth phase is larger, it is determined that it is a slot discharge, and the cumulative discharge charge amount in the fifth phase is obtained. Features.

In one aspect, the integrated discharge charge amount acquisition process may be performed when the change in the second phase is greater than or equal to the change in the first phase, or when the change in the fourth phase is greater than or equal to the change in the third phase. or when the change in the sixth phase is greater than or equal to the change in the fifth phase, the negative polarity partial discharge pattern is extracted, the negative polarity partial discharge pattern is vertically inverted, the phase is shifted by 180°, and the positive polarity partial discharge pattern is changed. Subtract the negative partial discharge pattern from the partial discharge pattern of , and compare the slope of the negative partial discharge pattern with the slope of the positive partial discharge pattern. If it is large, it is determined that it is a slot discharge.

In one embodiment, the discharge power amount acquisition process calculates a total discharge charge amount by adding the integrated discharge charge amount of each phase determined to be a slot discharge, and calculates a total discharge charge amount based on the total discharge charge amount. The amount of discharge charge per second is calculated, the amount of charge that ionizes oxygen is calculated based on the amount of discharge charge per second, the unit of the amount of charge is converted to calculate the discharge current, and the insulating layer of the wire is and a slot wall surface, calculate discharge power based on the discharge current and the voltage, and calculate discharge power amount per hour based on the discharge power. .

Further, as one aspect thereof, the ozone generation amount acquisition process defines a maximum ozone generation efficiency, and is based on the electric field in the gap between the insulating layer of the electric wire and the slot wall surface and the number density of oxygen molecules in the gap. A correction coefficient α is calculated, a correction coefficient β is calculated based on the dew point measured by the water vapor amount acquisition means, or the water vapor amount derived from the temperature/humidity, and the correction coefficient β is calculated based on the amount of water vapor derived from the dew point measured by the water vapor amount acquisition means, and the amount of discharge power, the correction coefficient α, and the correction coefficient are calculated. The first ozone generation amount per hour is determined based on the ozone concentration and the ozone flow rate, and the second ozone generation amount is determined based on the second ozone generation amount and the first ozone generation amount. The method is characterized in that the amount of third ozone generated due to discharge other than slot discharge is determined from the difference.

According to the present invention, it is possible to determine the amount of ozone generated from the partial discharge pattern in the insulation deterioration diagnostic device. In particular, it is possible to clearly distinguish between the amount of ozone generated due to slot discharge and the amount of ozone generated due to discharge from the straight portion outside the groove or the coil end.

FIG. 1 is a schematic diagram showing an insulation deterioration diagnosis device in an embodiment. The figure which shows an example of a non-contact type PD sensor and measurement data (partial discharge pattern). The flowchart which shows the algorithm which acquires the integrated discharge electric charge amount. FIG. 3 is a diagram showing a partial discharge pattern and first phase (A) to sixth phase (F). FIG. 3 is a diagram showing various abnormalities in partial discharge patterns. An explanatory diagram showing a comparison between a change in positive polarity and a change in negative polarity. Explanatory diagram showing decomposition of partial discharge pattern 5 is a flowchart showing details of the process in S5. 5 is a flowchart showing a method for determining whether or not slot discharge occurs. FIG. 7 is an explanatory diagram showing a method for determining whether or not slot discharge occurs. Flowchart showing an algorithm for calculating discharge power amount. A diagram showing the voltage V applied to the air gap. Flowchart showing an algorithm for determining the amount of ozone generated. The figure which shows the relationship between the amount of ozone, the amount of ozone generation, and the ozone decomposition rate.

Hereinafter, embodiments of the insulation deterioration diagnosing device according to the present invention will be described in detail based on FIGS. 1 to 14.

[Embodiment]
This embodiment describes an algorithm for calculating the amount of ozone generated from the PD pattern of slot discharge.

FIG. 1 shows the configuration of an insulation deterioration diagnostic device in this embodiment. The insulation deterioration diagnosis device in this embodiment is capable of diagnosing insulation deterioration not only when the diagnostic target is stopped (off-line) but also while the diagnostic target is in operation (on-line). Examples of the diagnosis target include a generator/electric motor (rotating machine). The insulation deterioration diagnostic equipment consists of the following equipment.

(1) PD sensor (partial discharge detection means)
A generator/motor (rotating machine) 1 and a switchboard 2 are connected by high voltage wiring 3. The PD sensor includes a TEV (Transient Earth Voltage) sensor that is not in contact with the high voltage wiring 3, a surface current sensor (the TEV sensor and the surface current sensor are collectively referred to as 4), a through electrode 5, and a vacuum capacitor 6. It is composed of either a non-contact type PD sensor 7 in combination with a voltage check capacitor 8 installed in the switchboard 2. Select a PD sensor according to the site situation. The non-contact PD sensor 7 and the voltage checking capacitor 8 in the switchboard 2 are provided with a detection impedance 9 (impedance Z: 1 to 20 kΩ) that is a combination of a resistor and a surge absorption element. Note that the through electrode 5 may be replaced with a flat electrode.

(2) Oscilloscope (partial discharge pattern acquisition means) 10
The signals of the various PD sensors in (1) are input via an HPF (high pass filter: frequency band 5 MHz or higher) and an LPF (low pass filter: frequency band 5 MHz or lower). From the signal passed through the HPF, a PD signal with noise components removed can be extracted, and from the signal passed through the LPF, a signal for determining the timing of taking in the PD signal can be extracted. The oscilloscope 10 acquires the partial discharge pattern of the phase and amount of discharged charge from the outputs of the LPF and HPF.

(3) Data logger 11
The data logger 11 acquires an output signal from a dew point meter or temperature/humidity sensor (water vapor amount acquisition means) 12 for measuring the dew point or water vapor amount of the cooling gas taken out from inside the generator/motor 1. There are two types of output signals: a voltage output type and a current output type (4-20mA).The current output type is input after being converted to a voltage signal via a 250Ω resistor.

The data logger 11 also receives an output signal from a temperature detection means (temperature measuring resistor) 13 attached to the stator of the generator/motor 1. In addition, output signals from the gas concentration meter 14 are input (the number of output signals is determined depending on the type of gas).

(4) Gas concentration meter (gas measuring means) 14
Measure the concentration of cooling gas (at least one of ozone, NOx, ammonia, hydrogen, carbon dioxide, and nitric acid) and gas flow rate taken out from inside the generator/motor 1, and calculate the gas concentration and gas flow rate. It is converted into a voltage signal and input to the data logger 11. Note that water vapor is measured by the water vapor amount acquisition means 12 described above.

(5) PC (data processing and storage means) 15
The PD signal recorded on the oscilloscope 10 and the dew point (or water vapor amount), gas concentration, gas flow rate, and stator temperature recorded on the data logger 11 are sent to the PC 15, and the discharge energy caused by ozone generation is calculated and stored. It also has display and alarm functions in the event of an abnormality.

The most important operations of the insulation deterioration diagnosis device of this embodiment will be explained with reference to FIG. 2 and subsequent figures.

FIG. 2(a) shows a state in which a three-phase AC power source (between lines: 11 kV, between ground: 6.35 kV) is applied to the deteriorated bar coil 16 to cause slot discharge. A non-contact PD sensor (a combination of a through electrode 5 and a vacuum capacitor 6) 7 is used to measure the partial discharge pattern propagating to the three-phase high voltage wiring 3. A detection impedance 9 (Z=10 kΩ: with arrester) is connected to the vacuum capacitor 6. FIG. 2(b) shows the measured partial discharge pattern.

The partial discharge pattern was obtained by measuring the output signal of the detection impedance 9 with an oscilloscope 10 and overwriting the partial discharge output signal for one cycle of AC 50 Hz 50 times. The horizontal axis represents the phase (one cycle of 20 ms expressed in degrees), and the vertical axis represents the measured amount of discharged charge.

The Sparks Instruments PORTABLE PARTIAL DISCHARGE ANALYZER FOR ROTATING MACHINES (model: TMS-6141) is used as an oscilloscope that can overwrite PD patterns.

In addition, since the U, V, and W phase partial discharges propagating to the three-phase high-voltage wiring 3 are captured by one electrode, the U, V, and W phase partial discharges are observed to overlap in one cycle. . The phase order of the power supply is U → W → V, and the measurement is based on the U phase, so the first partial discharge pattern (0 to 120°) is the U phase, and the second partial discharge pattern (120 to 240°) can be determined to be the W phase, and the third partial discharge pattern (240 to 360°) can be determined to be the V phase, and it can be determined that the partial discharge patterns are different for each phase. In the bar coil 16 used, not only slot discharge but also discharge due to delamination (large voids formed inside the insulating layer) occurred.

The amount of ozone generated is determined by the following algorithm.
(1) Algorithm to obtain cumulative discharge charge related to slot discharge (Figure 3)
(2) Algorithm to calculate discharge power amount from cumulative discharge charge amount (Figure 11)
(3) Algorithm for calculating the amount of ozone generated from the amount of discharged power (Figure 13)
FIG. 3 shows an algorithm for obtaining the integrated discharge power amount. The following explanation is for three-phase alternating current, 50 Hz (one cycle 20 ms).

(S1) In the PC 15, the PD pattern is acquired in three phases at once.

(S2) From the PD pattern shown in FIG. 2, a portion (phase) that changes most steeply in positive polarity is extracted (first phase (A) in FIG. 4). This is because the PD pattern of the slot discharge has a positive polarity and a steep shape, as shown in FIG. In other words, the negative polarity of the PD pattern of slot discharge is generally negligibly smaller than the positive polarity.

(S3) As shown in FIG. 4, a pattern change of negative polarity (second phase (B)) shifted by 180° from the position of the first phase (A) is extracted.

(S4) Compare the patterns of the first phase (A) and the second phase (B). The comparison is made based on the slope and size, as shown in FIG. If the change in the first phase (A) is greater than the change in the second phase (B), proceed to S5; if the change in the first phase (A) is less than or equal to the change in the second phase (B), proceed to S6. do.

(S5) If the change in the first phase (A) is larger, it is determined that it is a slot discharge, and the integrated discharge charge amount Qi (A) is obtained. As shown in FIG. 7, the acquisition method is to apply a triangular shape to cover the PD pattern of the first phase (A) and calculate its area. However, in the PD pattern obtained in FIG. 2, the same phase and the same amount of charge are overwritten multiple times, and the patterns are color-coded depending on the frequency (number of times). This is decomposed to find out how many times the overwriting occurs, and the area of the PD pattern of each frequency (number of times) is calculated and added to obtain the integrated discharge charge amount Qi (A).

Here, a method for calculating the integrated discharge charge amount Qi (A) will be explained based on FIGS. 7 and 8.

(S21) The overwritten PD pattern is decomposed. The number of times the PD pattern is overwritten at the same position is indicated by a number. Check how many times the same phase and discharge charge amount are overwritten. Those separated by one point are excluded. As shown in Figure 7, the number of overwritten data minus 1 from (original data: j = 1) is (1st time: j = 2), and from (1st time: j = 2) The number of overwritten times minus 1 is (2nd time: j=3). This is repeated to decompose the PD pattern.

(S22) Let the number of decompositions be j and k=1.

(S23) Draw a triangle whose apex is the peak value near the first phase (A).

(S24) Determine the base and height of the triangle.

(S25) Calculate the cumulative amount of discharged charge Qik(A) using Qik(A)=base×height/2.

(S26) Increment k.

(S27) It is determined whether k is larger than j. If k is larger than j, the process moves to S28, and if k is less than or equal to j, the process returns to S23.

(S28) Calculate the cumulative amount of discharged charge Qi (A) by Qi (A) = ΣQik (A).

Returning to the explanation of FIG. 3.

(S7) As shown in FIG. 4, the positive polarity portion shifted by −120° from the position of the first phase (A) is extracted as the third phase (C).

(S8) As shown in FIG. 4, a negative polarity position shifted by 180° from the third phase (C) is extracted as the fourth phase (D).

(S9) Compare the pattern (magnitude, slope) of the change in the third phase (C) and the change in the fourth phase (D), and find that the change in the third phase (C) is greater than the change in the fourth phase (D). If the change in the third phase (C) is also larger than the change in the fourth phase (D), the process moves to S11.

(S10) The same process as S5 is performed to obtain the integrated discharge charge amount Qi(C).

(S12) As shown in FIG. Extract as (E).

(S13) As shown in FIG. 4, a negative polarity position shifted by 180° from the fifth phase (E) is extracted as the sixth phase (F).

(S14) Compare the pattern (magnitude, slope) of the change in the fifth phase (E) and the change in the sixth phase (F), and if the change in the fifth phase (E) is larger, proceed to S15, If the change in the fifth phase (E) is less than or equal to the change in the sixth phase (F), the process moves to S16.

(S15) The same process as S5 is performed to obtain the integrated discharge charge amount Qi(E).

(S6, S11, S16) If it cannot be determined whether it is a slot discharge or not, (if the change in the second phase (B) is greater than the change in the first phase (A), the change in the fourth phase (D) If the change is greater than or equal to the change in the third phase (C), or if the change in the sixth phase (F) is greater than or equal to the change in the fifth phase (E), the determination method shown in FIGS. 9 and 10 is performed. The judgment method is to flip the negative PD pattern upside down and shift it 180 degrees, and then subtract the negative PD pattern from the positive PD pattern once to determine if the positive PD pattern contains delamination or internal voids. After reducing the negative polarity, the positive polarity PD pattern and the negative polarity PD pattern are compared.

If the magnitude of the change in the first phase (A)≒the magnitude of the change in the second phase (B), a slot discharge exists hidden in the PD pattern of a large partial discharge (delamination, internal void) in the insulating layer. There are cases. At this time, the processes shown in FIGS. 9 and 10 are performed to determine whether slot discharge is occurring or not.

(S31) In the PC 15, the PD pattern is acquired in three phases at once.

(S32) Extract a negative polarity PD pattern.

(S33) The negative polarity PD pattern is inverted vertically.

(S34) Shift the phase of the negative polarity PD pattern by 180°.

(S35) A negative-polarity PD pattern is drawn only once from a positive-polarity PD pattern.

(S36) It is determined whether slope 1 of the negative polarity PD pattern is smaller than slope 2 of the positive polarity PD pattern. If the slope 1 is smaller than the slope 2, the process moves to S37 and it is determined that it is a slot discharge, and if the slope 1 is more than or equal to the slope 2, the process moves to S38 and it is determined that it is not a slot discharge (delamination).

This utilizes the fact that partial discharge patterns other than slot discharge have symmetry between positive polarity and negative polarity, as shown in FIG. By comparison, if the slope of the positive PD pattern is large, it is a slot discharge.

Next, the amount of discharge power that contributes to ionizing oxygen is calculated. As shown in FIG. 11, the amount of discharged power is calculated in the processes of S41 to S47.

(S41) The total discharge charge amount Qi (A), Qi (C), and Qi (E) obtained in FIG. 3 (determined to be slot discharge) are added together to determine the total discharge charge amount Q.

(S42) Since the total discharge charge amount Q is the discharge charge amount per cycle (20 ms), it is multiplied by 50 to obtain the discharge charge amount Q per second (1 s).

(S43) Since the proportion of oxygen in the air is 20.9%, the discharge charge amount Q(1s) is multiplied by 0.209 to obtain the charge amount Q(O) used to ionize oxygen.

(S44) Here, since the unit of charge Q(O) is [C/s] and the unit of current is [A] = [C/s], Q(O) can be regarded as discharge current I. can.

(S45) As shown in FIG. 12, slot discharge occurs in the gap 19 created between the surface of the insulating layer 17 of the electric wire and the slot wall surface 18. At this time, a potential V that is substantially the same as the applied voltage V is applied to the surface of the insulating layer 17, and the slot wall surface 18 is at a potential of 0V because it is grounded. Therefore, the potential applied within this gap 19 is V.

(S46) The discharge power P generated within the air gap 19 is calculated by I×V.

(S47) Further, the discharge power amount W is determined by integrating the discharge power P over one hour.

Next, each of the first to third ozone generation amounts G(1), G(2), and G(3) are determined. The algorithm is shown in FIG.

(S51) Define the maximum ozone production efficiency η (eta). The maximum ozone generation efficiency η is set to η≈80 g/kWh (in the case of silent discharge) using the value of Non-Patent Document 1 below.
Noriichi Tabata (Mitsubishi Electric Corporation) "Ozone Generation and Production Efficiency", Journal of the Japan Society for Plasma and Nuclear Fusion 74 (10), 1119-1126, 1998-10 (S52) Calculate E/n and use the following formula. to find the correction coefficient α. Here, E is the electric field in the gap (voltage to ground/distance of the gap), and n is the number density n of oxygen molecules in the gap. For example, when the voltage to ground is 6.35 kV, E/n=113.4 and α=0.86. α=-6×10-5×(E/n)2+0.0209×(E/n)-0.7396 (S53) Derived from stator temperature, dew point or temperature/humidity measured by water vapor amount acquisition means 12 A correction coefficient β due to ozone decomposition is determined from the amount of water vapor. Generally, information such as the fact that ozone is easily decomposed at high temperatures of 80° C. or higher is given as a correction coefficient β for correction.

(S54) The first ozone generation amount G(1) per hour is determined by considering the correction coefficients α and β. G(1)=η×W×α×β, and this value is the amount of ozone generated per hour released from inside the slot.

Next, the third ozone generation amount G(3) generated from the straight portion outside the groove and the coil end is determined.

(S55) Gas concentration (ozone concentration) C [mg/L] is measured using the gas concentration meter 14.

(S56) Measure the gas flow rate (ozone flow rate) Q [L/min] flowing through the gas concentration meter 14.

(S57) Obtain the ozone amount M per hour from the ozone concentration C [mg/L] and the ozone flow rate Q [L/min].

M [mg] = C [mg/L] x Q [L/min] x 60 [min]
(S58) As shown in FIG. 14, especially in the closed type generator/motor 1, air is circulated within the system for cooling, and ozone is decomposed during the circulation. Therefore, the second ozone generation amount G(2) actually emitted from the ozone generation source 20 is different from the ozone amount measured by the gas concentration meter 14.

To correct this, the ozone amount M is divided by the ozone decomposition rate γ (gamma) to obtain the actual second ozone generation amount G(2). Note that the ozone decomposition rate γ is determined by taking into account the influence of the volume inside the generator/motor 1, the temperature, the distance between the ozone generation source and the gas inlet, and the like.

(S59) The difference between the first ozone generation amount G(1) calculated from the PD pattern of slot discharge and the second ozone generation amount G(2) calculated from the ozone concentration measured from the gas concentration meter 14 is other than slot discharge. This is the third ozone generation amount G(3) due to the discharge occurring in the groove, and this can be determined to be the ozone generation amount from the straight line portion outside the groove and the coil end.

As shown above, by applying the algorithm in this embodiment, the amount of ozone generation can be determined from the partial discharge pattern. Moreover, the ozone generation sources can be distinguished into at least two sources (inside the slot, a straight part outside the groove, and the coil end).

Although only the specific examples described in the present invention have been described in detail above, it is obvious to those skilled in the art that various modifications and modifications can be made within the scope of the technical idea of the present invention. Naturally, such variations and modifications fall within the scope of the claims.

1... Generator/Electric motor (rotating machine)
2...Switching board 3...High voltage wiring 4...TEV sensor, surface current sensor 5...Through electrode 6...Vacuum capacitor 7...Non-contact PD sensor 8...Capacitor for voltage confirmation 9...Detection impedance 10...Oscilloscope (partial discharge pattern acquisition means) )
11...Data logger 12...Dew point meter, temperature/humidity sensor (water vapor amount acquisition means)
13...Temperature detection means 14...Gas concentration meter (gas measurement means)
15...PC (data processing storage means)
16...Bar coil 17...Insulating layer 18...Slot wall surface 19...Gap 20...Ozone generation source

Claims (6)

A rotating machine insulation deterioration diagnosis device,
Partial discharge detection means for detecting partial discharge of the rotating machine;
temperature detection means for measuring the temperature of the stator of the rotating machine;
Water vapor amount acquisition means for measuring the dew point or temperature/humidity of the cooling gas inside the rotating machine;
a gas measuring means for measuring ozone concentration and ozone flow rate inside the rotating machine;
Partial discharge pattern acquisition means for acquiring a partial discharge pattern of phase and discharge charge amount from the detected partial discharge;
an integrated discharge charge amount acquisition process for obtaining an integrated discharge charge amount related to slot discharge from the partial discharge pattern; a discharge power amount acquisition process for obtaining a discharge power amount from the integrated discharge charge amount; a data processing storage means that performs an ozone generation amount acquisition process for determining a first ozone generation amount;
An insulation deterioration diagnostic device comprising: The ozone generation amount acquisition process includes:
A second ozone generation amount is determined based on the ozone concentration and the ozone flow rate, and a third ozone generation amount is determined based on the difference between the second ozone generation amount and the first ozone generation amount due to discharge occurring other than slot discharge. 2. The insulation deterioration diagnostic device according to claim 1, wherein: The integrated discharge charge amount acquisition process includes:
From the partial discharge pattern, extract a first phase of positive polarity and the steepest change, extract a second phase of negative polarity change that is 180° out of phase with respect to the first phase, and and a change in the second phase, and if the change in the first phase is larger, it is determined that it is a slot discharge, and an integrated discharge charge amount in the first phase is obtained;
A third phase of positive polarity change that is -120° out of phase from the first phase is extracted, a fourth phase of negative polarity change that is 180° out of phase with respect to the third phase, and Comparing the change in the third phase with the change in the fourth phase, if the change in the third phase is larger, determining that it is a slot discharge and obtaining the cumulative amount of discharge charge in the third phase,
A fifth phase of positive polarity change that is -240° out of phase from the first phase is extracted, a sixth phase of negative polarity change that is 180° out of phase with respect to the fifth phase, and A change in the fifth phase is compared with a change in the sixth phase, and if the change in the fifth phase is larger, it is determined that it is a slot discharge, and an integrated discharge charge amount in the fifth phase is obtained. Item 2. Insulation deterioration diagnostic device according to item 1 or 2. The integrated discharge charge amount acquisition process includes:
If the change in the second phase is greater than or equal to the change in the first phase, or if the change in the fourth phase is greater than or equal to the change in the third phase, or if the change in the sixth phase is greater than or equal to the change in the fifth phase. In cases where there is more than a change,
Extract the negative partial discharge pattern, flip the negative partial discharge pattern upside down and shift the phase by 180°, subtract the negative partial discharge pattern from the positive partial discharge pattern, and calculate the slope of the negative partial discharge pattern. Insulation deterioration according to claim 3, characterized in that the slope of the positive polarity partial discharge pattern is compared with the slope of the positive polarity partial discharge pattern, and if the positive polarity partial discharge pattern is larger than the negative polarity partial discharge pattern, it is determined that it is a slot discharge. Diagnostic equipment. The discharge power amount acquisition process includes:
The total discharge charge amount is calculated by adding the cumulative discharge charge amount of each phase determined to be slot discharge, and the discharge charge amount per second is calculated based on the total discharge charge amount, and the total discharge charge amount per second is calculated. Calculate the amount of charge that ionizes oxygen based on the amount of discharge charge, convert the unit of the charge amount to calculate the discharge current, find the voltage related to the gap between the insulating layer of the wire and the slot wall surface, 5. The insulation deterioration diagnosing device according to claim 3, wherein the discharge power is calculated based on the discharge current and the voltage, and the amount of discharge power per hour is calculated based on the discharge power. The ozone generation amount acquisition process includes:
The maximum ozone generation efficiency was defined, the correction coefficient α was calculated based on the electrolysis in the gap between the insulating layer of the electric wire and the slot wall surface, and the number density of oxygen molecules in the gap, and the correction coefficient α was measured by the water vapor amount acquisition means. A correction coefficient β is calculated based on the amount of water vapor derived from the dew point or the temperature/humidity, and the first ozone generation amount per hour is calculated based on the discharge power amount, the correction coefficient α, and the correction coefficient β. The second ozone generation amount is determined based on the ozone concentration and the ozone flow rate, and the third ozone generation amount due to the discharge occurring other than the slot discharge is determined by the difference between the second ozone generation amount and the first ozone generation amount. The insulation deterioration diagnostic device according to any one of claims 1 to 5, characterized in that the amount of ozone generated is determined.

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