JP2002365326A - Insulation diagnostic method and insulation diagnostic device for dynamoelectric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interlayer insulation diagnostic technique, capable of discriminating partial discharge by interlayer discharge from a partial discharge through ground insulation for diagnosing insulation state. SOLUTION: A probe 2, for detecting a partial discharge current from a coil to be diagnosed, is connected every coil of a dynamoelectric machine or every block comprising two or more coils, and the partial discharge current detected by the probe 2 is read via an interface device 540. The polarity of the read partial discharge current is determined by a computer 510, to discriminate whether the partial discharge current concerned is generated by partial discharge by interlayer insulation or by partial discharge by ground insulation, it is determined whether or not an abnormality exists in the interlayer insulation by comparing with a preliminarily stored reference value, and the result is outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for diagnosing interlayer insulation of a rotating electric machine coil, and more particularly to providing knowledge on interlayer insulation for a newly designed rotating machine.
The present invention relates to a technique for diagnosing interlayer insulation that contributes to operation while monitoring the insulation state of a rotating machine.

[0002]

2. Description of the Related Art Generally, a rotating electric machine is formed of a stator 181 and a rotor 182 as shown in FIG. The stator coil 160 of the rotating electric machine is installed in the stator slot 183. When the coil 160 is removed from the slot, it has the shape shown in FIG. 39A. Further, as shown in the cross-sectional view of FIG.
The coil conductor bundle 172 formed by winding the coil conductor 171 whose outer periphery is covered with the coil 70 a plurality of times is provided with ground insulation 173 and formed. The former interlayer insulation 170 is provided between coil conductors,
That is, the windings are insulated. On the other hand, the ground insulation 173 is
The coil conductor 171 is insulated from the core which is at the earth potential.

In general, when a rotating electric machine is operated at a commercial frequency, (rated voltage) / √3 V is applied to the ground insulation. On the other hand, the interlayer insulation between coil conductors requires several volts.
Only about voltage is applied. For this reason, the conventional insulation diagnosis is mainly performed on the ground insulation.

On the other hand, in recent years, rotary electric machines have been actively driven by inverters. In the inverter drive motor, for example, Technical Report No. 739 of the Institute of Electrical Engineers of Japan, p. Like 14,
It has been reported that a large voltage is shared by interlayer insulation. In particular, in an inverter using an IGBT that is a high-speed switching element, a large voltage is applied due to interlayer insulation. For this reason, in the inverter-driven rotating electric machine, insulation diagnosis of not only ground insulation but also interlayer insulation is required.

[0005] Conventionally, as a diagnostic device for such interlayer insulation, for example, a partial discharge which is one of the degradation signals of interlayer insulation disclosed in JP-A-8-122388 and JP-A-9-257762 is disclosed. There is a device to detect. Also,
There is an apparatus disclosed in Japanese Patent Application Laid-Open No. 9-257862 for detecting an interlayer short-circuit state. In the former interlayer insulation diagnostic device, a voltage is applied to the interlayer insulation by a surge power supply such as a high-frequency high-voltage power supply or an impulse, and a current,
Detects various signals such as electromagnetic waves and sound waves. On the other hand, the latter interlayer insulation diagnostic device applies a surge voltage to the coil,
The short circuit of the interlayer insulation is detected from the difference in the detection signal waveform generated due to the difference in the propagation time of the surge.

[0006]

In the former device for diagnosing interlayer insulation, when a voltage is applied to the coil, the voltage is applied not only to the interlayer insulation but also to the ground insulation. For this reason, partial discharge occurs not only in interlayer insulation but also in ground insulation. However, in the former method, a partial discharge in interlayer insulation and a partial discharge in ground insulation cannot be distinguished. For this reason, it was difficult to diagnose the insulation of the interlayer insulation.

On the other hand, an interlayer insulation diagnostic device using a surge voltage can detect only a complete interlayer short-circuit state, as described in JP-A-8-122388. Therefore, it is not sufficient as an insulation diagnosis of interlayer insulation.

As described above, conventionally, it has been difficult for a rotary electric machine to diagnose the insulation deterioration of interlayer insulation. In such a situation, there is a problem that it is difficult to drive a commercial frequency power supply or a used rotating electric machine manufactured for an old type inverter power supply with a new inverter power supply.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an interlayer insulation diagnosing technique capable of diagnosing an insulation state by distinguishing between partial discharge in interlayer insulation and partial discharge in ground insulation.

[0010]

SUMMARY OF THE INVENTION The basic principle of the present invention is to distinguish between partial insulation between interlayer insulation and ground insulation based on the polarity of a discharge current detected by a discharge current sensor. As a result, an interlayer insulation diagnosis for distinguishing partial discharge between interlayer insulation and ground insulation and a device therefor are realized.

[0011] For example, in a first aspect of the interlayer insulation diagnosis of the present invention, a power supply line or a coupling capacitor connected to a power supply line of a lead portion of a rotating electric machine and a discharge current sensor installed at a connection between coils of the rotating electric machine. The partial discharge between the interlayer insulation and the ground insulation is distinguished based on the polarity of the partial discharge current detected by.

Further, in the second aspect, instead of attaching a discharge current sensor to the inter-coil connection portion, a partial discharge flowing from the inter-coil connection portion conductor to the ground is capacitively coupled between the inter-coil connection portion conductor and the ground. By detecting a current with a discharge current sensor, an interlayer insulation diagnosis is performed. In this case,
In particular, in a rotating electrical machine in which the neutral point is grounded, the discharge current sensor can be installed on the neutral point ground wire.

The present invention provides, as another aspect, for example,
The measurement of the ground voltage waveform of each coil can also be realized by an interlayer insulation diagnostic device provided with a measuring unit for distinguishing between partial insulation and interlayer discharge based on the phase of the voltage waveform and the polarity of the discharge current.

Further, for example, a connection portion between coils, or
An interlayer insulation diagnostic device in which a discharge current sensor is provided at the end of the rotating electrical machine coil end opposite to the coil connection side, instead of attaching a discharge current detection sensor to the capacitive connection between the coil connection and the ground. It can also be realized by

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 shows an interlayer insulation diagnostic apparatus according to a first embodiment. In the present embodiment, an example will be described in which the induction motor 10 is used for performing an interlayer insulation diagnosis.

In the interlayer insulation diagnostic apparatus of the present embodiment, the test power supply 7 and the induction motor 10 are connected, and the induction motor 1
0, a coupling capacitor is arranged on the leading side of the first coil of any phase, a first current probe 1 for detecting a current flowing through the coupling capacitor, and an induction motor 1
The current probe 2 includes a current probe 2 for detecting a current flowing through the stator-to-coil-coil connection unit 14, and a diagnosis support device 400 that receives an output signal of each of the current probes 1 and 2 to perform diagnosis. The diagnosis support device 400 includes the current probes 1 and
2 multi-channel high-pass filter (cutoff frequency 1 to 100 MHz) for removing power supply frequency components from the output signal
z) 3, a logical discriminator 4 for performing logical judgment on the output signal from which the power supply frequency component has been removed, and a discharge detector 5 for detecting a discharge state.

In this embodiment, specifically, the U-phase first coil 1 of the induction motor 10 (6.6 kV, 500 kVA)
1 is connected to a test power supply 7 (6.6 kV, 200 kHz, sine wave), and the first coil 13 of the V and W phases is connected to the ground. The coupling capacitor 6 is connected to the U-phase power line 9.
(100 pF), the low-voltage side of the coupling capacitor 6 is connected to the ground, and the current probe 1 is installed on the connection line. On the other hand, the current probe 2 is installed at the connection part 14 between the stator coils of the induction motor 10. FIG. 1 shows an example in which the current probe 2 is arranged at a connection portion 14 between the U-phase first coil 11 and the U-phase second coil.

The output signals of the current probes 1 and 2 are input to a multi-channel high-pass filter (cutoff frequency 1 MHz) 3 where power supply frequency components are removed. Thereafter, it is input to the discharge detector 5 via the logical discriminator 4. For example, a digital oscilloscope (band 1 GHz, sampling frequency 4 GS / s) is used as the discharge detector 5. The discharge detector 5 detects the discharge state and displays the result, so that the coil can be diagnosed. That is, the discharge detector 5 functions as a device that supports insulation diagnosis.

The test power supply 7 includes a high-frequency power supply 7a,
And an internal impedance 8. This internal impedance 8 functions as a protection resistor and a blocking impedance.

Each of the current probes 1 and 2 is composed of, for example, a coil for detecting a current, and functions as a sensor. Each of the current probes 1 and 2 has a structure in which a part of the coil can be opened and closed, and a wire to be detected can be arranged in the coil. When a part of the line to be detected can be detached, the current probes 1 and 2 need not be able to be opened and closed. Further, one or both of the current probes 1 and 2 can be incorporated in a rotating machine in advance. When diagnosing such a rotating machine, a built-in current probe can be used.

FIG. 4 shows an example of the logical discriminator 4. In the logic discriminator 4, the discharge currents of the current probes 1 and 2 are compared with the ground potential by the comparator 190, and are converted into positive polarity and negative polarity signals of 5V and 0V, respectively. The polarity signal is exclusive when detecting partial discharge of interlayer insulation.
A switch 194 which is input to an OR (exclusive OR) circuit 191 and an inverting circuit 192 and whose output is turned on at H level is provided.
Is input to the trigger terminal. On the other hand, when the partial discharge of the ground insulation is detected, the output of the exclusive OR circuit 191 is input to the trigger terminal of the switch 194 by the switch 193. When the pulse width of the partial discharge signal is small, the output of the comparator 190 may be input to a monostable multivibrator to extract a signal having a pulse width at which the logic circuit operates.

The logical discriminator 4 can determine whether the partial discharge is a partial discharge in interlayer insulation or a partial discharge in ground insulation. FIG. 3 shows an example in which an interlayer insulating partial discharge current is discriminated as an output signal 26 by the logic discriminator 4. In FIG. 3, the interlayer insulation partial discharge current 22 is indicated by a solid line, and the ground insulation partial discharge current 23 is indicated by a broken line.
Is represented.

Next, the principle and operation of the diagnostic apparatus for interlayer insulation according to the first embodiment will be described.

FIG. 2 shows a ladder-type equivalent circuit model of the induction motor coil, and a partial discharge current path for interlayer insulation and ground insulation at the time of positive polarity discharge. In FIG. 2, for simplicity of description, one coil is represented by a T-type equivalent circuit of a capacitance C _g of ground insulation, a capacitance C _r of interlayer insulation, and an inductance L of the coil. The high frequency component of the partial discharge current is
Flow capacitance C _r of the inter-layer insulating, low-frequency components to flow the inductance L of the coil, in particular, considered as one block parallel circuit portion C _r and L, shows the path of the discharge current. The polarity of the current probes 1 and 2 is such that the current flowing in the direction toward the test phase lead 27 outside the rotating electric machine is positive, and the inside of the rotating electric machine is from the test phase lead 27 to the other phase lead 2.
The direction of the current flowing through 8 is positive. In FIG. 2, it is assumed that either a partial discharge of interlayer insulation or a partial discharge of ground insulation occurs, and the occurrence position is indicated by a star mark 2.
It is assumed that a partial discharge of interlayer insulation occurs at a position indicated by 0, and a partial discharge of ground insulation occurs at a position indicated by an asterisk 21.

In the current probe 1 of the interlayer insulation diagnostic device,
The discharge currents of the interlayer insulation and the ground insulation have the same polarity. For this reason, it is not possible to distinguish between partial discharge in interlayer insulation and partial discharge in ground insulation. On the other hand, in the current probe 2, the partial discharge current in the interlayer insulation and the discharge current in the ground insulation have opposite polarities. However, when the polarity of the power supply voltage is inverted, the partial discharge currents of the interlayer insulation and the ground insulation are also inverted. For this reason, the current probe 2 alone cannot distinguish between partial discharge in interlayer insulation and partial discharge in ground insulation. However,
When the partial discharge currents detected by the current probes 1 and 2 are compared, as shown in Table 1, regardless of the discharge polarity,
It has the same polarity in the interlayer insulation partial discharge, and has the opposite polarity in the ground insulation partial discharge.

[0027]

[Table 1] Therefore, in the logic discriminator 4, the current probes 1, 2
By logically discriminating the combinations of polarities shown in Table 1, it is possible to distinguish between partial discharge in interlayer insulation and partial discharge in ground insulation. That is, the logical discriminator 4 detects any partial discharge of the interlayer insulation by passing any signal of the current probes 1 and 2 to the discharge detector only when the discharge currents of the current probes 1 and 2 have the same polarity. can do. On the other hand, only when the discharge current pulse has the opposite polarity, by passing the signal through the discharge detector, the partial discharge of the ground insulation can be detected.

The partial discharge current 24 detected by the current probe 1 and the partial discharge current 25 detected by the current probe 2 are input to the logic discriminator 4. The logical discriminator 4 performs a logical determination based on the above-described operation principle and outputs an output signal 26. In the example of FIG. 3, an interlayer insulating partial discharge current is detected.

The above polarity discrimination is represented by a truth table as shown in Table 2.
Becomes However, in the input of Table 2, the positive polarity of the current probe detection current is “1” and the negative polarity is “0”. The output is "1" if true and "0" if false.

[0030]

[Table 2] FIGS. 2, 3 and Table 1 show the partial discharge discriminating action of the interlayer insulation and the ground insulation of the first coil. For other coils, a current probe is installed at the connection between the coils at both ends of the coil, and by comparing the polarities of the discharge currents, it is possible to discriminate between partial discharge in interlayer insulation and partial discharge in ground insulation. Also, a plurality of coils are made into one block,
By installing current probes on the power supply line sandwiching each block, the capacitor connected to the power supply line, and the connection between the coils, the partial discharge in the interlayer insulation and the part in the ground insulation generated by the coils in the block Discharge can be determined. In addition, when installing a current probe at the lead of the non-partial discharge measurement phase, the current probe can be placed at the ground wire connecting the lead and the ground.

Further, in the first embodiment, it is possible to specify a partial insulation discharge generating coil to the ground or measure a partial discharge generated from the specific coil based on the polarity of the partial discharge current. This is because, in the present embodiment, the discharge current polarities of the current probes provided at both ends of the grounding partial discharge generating coil are opposite.

On the other hand, in the interlayer insulation partial discharge, no matter which coil generates the partial discharge, all the current probes
In the positive discharge, a positive current is detected, and in the negative discharge, a negative current is detected. For this reason, it is not possible to find an interlayer insulating partial discharge generating coil only by the polarity of the partial discharge current. However, the interlayer insulating partial discharge generating coil can be specified by measuring the delay of the time when the discharge current reaches each current probe after the partial discharge occurs. This is because the discharge current is detected earliest by the current probe closest to the interlayer insulating partial discharge coil.

Table 3 shows the current polarities of the respective current probes when a partial discharge of the fourth coil to the ground occurs from the outlet. The polarity of the discharge current is reversed with respect to the grounding partial discharge generating coil. For this reason, by examining the polarity pattern of the discharge current of each current probe, or by scanning while reducing the number of coils in the test block, and finding a coil whose polarity is reversed, the ground-isolated partial discharge generating coil can be specified.

[0034]

[Table 3] FIG. 5A shows an example in which the discharge current pulse determined from the discharge current polarity pattern in Table 3 as the interlayer insulating partial discharge is displayed with the vertical axis representing the current and the horizontal axis representing the time. FIG. 5B shows the positional relationship between the interlayer insulating partial discharge generating coil and each current probe. The reference numerals in FIG. 5A correspond to the reference numerals indicating the current probes in FIG. 5B. The discharge current is detected earliest by the current probes 231 and 232 installed at both ends of the coil 230 (indicated by an asterisk in the figure) where the interlayer insulation partial discharge has occurred. Further, as the distance from the discharge source increases, the arrival time of the discharge current is delayed. Therefore, the interlayer insulating partial discharge generating coil can specify the interlayer insulating partial discharge generating coil by finding the current probe from which the discharge current is detected earliest. This method can be specified by triggering the rise (or fall) of each current pulse and comparing the rise (or fall) times as described above.

In the apparatus described so far, the diagnosis itself is performed by the operator. However, the insulation diagnosis can be performed by the device itself based on the result of the discharge detection. As such a system, there is a system using the information processing device 500, for example, a system shown in FIGS. 26, 28, 31, and the like.

FIGS. 6 to 9 show current probes installed on all coils, and specify the interlayer insulation and ground insulation partial discharge sources of each coil from the polarity pattern and the discharge current arrival time.
The example which measured each partial discharge characteristic is shown. On the other hand, FIGS. 10 and 11 show a search flowchart for scanning while reducing the number of coils in the test block to find a coil whose polarity is reversed. A program for realizing this flowchart is stored in an external storage device 5
14 is stored. For this search, a multi-channel high-pass filter 3 and a logical discrimination circuit 4 shown in FIG.
Are provided corresponding to the current probes installed for all the coils. In addition, a device for measuring the time change of the discharge is installed in the same manner. The number of these devices that do not need to be used at the same time can be reduced by switching and using them. Then, an interface device 540 (FIG. 3) for converting the obtained signal into a digitally processable signal.
7) through the computer 510 (see FIG. 37).
And performs a search process, and also performs a subsequent data process, a screen display process, and the like. The screen display processing includes displaying screens illustrated in FIGS. 6 to 9, and
An instruction operation for this is given.

Here, the configuration of the computer 510 will be described. As shown in FIG.
Has a central processing unit (CPU) 511, a read only memory (ROM) 512, a random access memory (RAM) 513, and an external storage device 514 including a hard disk device or the like. External storage device 514
Stores an operating system, various application programs, and the like as programs executed by the computer 510. A typical example of the application program is a diagnostic program executed in the present invention. Further, as data, for example, various measurement data described later and various values obtained from the measurement data are stored. These data are processed by the computer 510 as described later, and are used for displaying in the form of a characteristic diagram or the like. An example of processing by the computer 510 is shown in FIG.
6, FIG. 31, FIG. 37, etc. The processing will be described later.

The computer 510 includes an input device such as a keyboard 521 and a mouse 522, a display device 530 such as a liquid crystal display, and an interface device 540 that receives measured values and outputs a signal for controlling the measuring device. Connected. The information processing system 500 includes the computer 510 and these devices. The information processing system 500 can be configured by a general computer system. In addition, it can be configured using a control computer. Further, the configuration can be made using a dedicated computer. Here, as the measuring device, the first coil 1,
The second coil 2, the test power supply device 7, and a plurality of second coil 2 selection switching devices are exemplified. Further, the diagnosis support device 400 shown in FIG. 1 can be used as a measurement device.

The interface device 540 includes a multi-channel high-speed A / D converter 541 and a digital filter 542.
Etc. Although not shown, a transmission / reception driver for transmitting / receiving signals to / from the measurement device is provided. Further, although not shown, the computer 5
There is also a circuit for transmitting the command from 10.

FIGS. 6 to 9 show examples of screens showing the measurement results. Each of them is shown as an example of the explanation screen displayed on the display device 530 (see FIG. 37) connected to the computer 510. In the example of FIG. 37, the detected data is taken into the computer 510 via the interface device 540 and processed by using a program and data prepared in advance in the external storage device 514 to be displayed. As a program, for example, EMT
P (Elector-Magnetic Transients Program) is used.

In FIG. 6 to FIG.
Along the lower edge of 300, the selection icon group 531
0 is displayed, and a screen to be displayed can be selected by clicking any one. In the upper left part, a function explanation section 5320 including symbols f6 and f7 indicating function keys assigned in advance and an explanation thereof is displayed. An area 5330 for displaying a characteristic diagram or the like is set in a large part of the upper side of the screen 5300. A necessary key among the function keys f6 and f7 displayed on each screen is
By operating in step 1, the characteristic chart assigned to each can be selectively displayed. In this embodiment and other embodiments described later, the function keys are displayed as icons. As a result, mouse 5
With 22, a pointer (not shown) can be positioned on the corresponding function key and clicked to select the function.

As the selection icon group 5310, for example, in FIG. 6, [FIG. B], [FIG. C], [FIG. D], [v setting], [n setting], [ground], [coil], Save,
The [Diagnosis] and [End] icons are displayed. These icon groups are displayed with some of them changed depending on the screen to be displayed.

In FIG. 6, the function key f6
, And a coil sharing voltage display <interlayer insulation maximum discharge charge-voltage characteristic> is assigned to f7. In the current display state of FIG. 6, f7 is selected, FIG. A-1 (coil sharing voltage distribution) is displayed in the left area 5331 of the characteristic diagram display area 5330, and FIG. Discharge charge-voltage characteristics) are displayed. Here, in FIG. A-1, the target coil is represented by a figure, for example, a square, and the connection state of the coil is connected to the figure corresponding to the coil for each phase of UVW by a corresponding number. The connected state is schematically displayed. On the other hand, in A-2, the characteristics are shown in a graph. When there are many coils, they may be similarly described in units of coil blocks.

FIG. 7 shows a display screen after the icon 5311 of [FIG. B] displayed on the screen in FIG. 6 is clicked. In this screen, the function key f6 is selected. In FIG. 7,
In the state where FIG. B-1 is displayed in the left area 5331, a message "Click to display the maximum discharge charge-voltage characteristic" is displayed on the screen, and that portion is a selection key. Similar displays are also shown in FIGS. 8 and 9.

FIG. 7 schematically shows a state in which the figures representing the coils are connected to the corresponding numbers of the respective phases of UVW in the left area of the characteristic diagram display area 5330 in the same manner as in FIG. it's shown. However, FIG. 7 shows a state in which the mouse pointer MP is positioned on any one of the coils, and a button of the mouse 522 is clicked to select the coil. That is, the display mode of the graphic representing the selected coil is changed to clearly indicate that the selected coil is selected. In the case of FIG. 7, for the sake of convenience, the figure representing the coil is represented by hatching. Of course, when another coil is selected, a hatched line is added to the figure indicating the other coil. On the other hand, in the right area 5332 of the characteristic diagram display area 5330, FIG. B-2 (coil maximum discharge charge amount-voltage characteristic) for the selected coil is displayed. In addition, about the aspect of this display,
Basically, the same applies to FIGS. 8, 9, 27, 29, and 30.

In the processing of FIG. 10, first, m = 0, n
= (U, V phase coil number) (step 101)
A partial discharge in interlayer insulation and a partial discharge in ground insulation are identified (step 102). In the interlayer insulation partial discharge, since the polarity of the discharge current detected by all the current probes is the same, it can be distinguished from the ground insulation partial discharge. This detection
It can be performed by taking in the result performed in the logic discriminator 4 described above. Of course, without using a logical discriminator, each detection signal can be taken into a computer and discriminated by determining the polarity of each of them as in a logical discriminator.

When the interlayer insulation partial discharge is measured,
The search program displays a screen recommending that “a large number of current probes are installed and the generated coil is identified from the difference in the partial discharge pulse detection time of each current probe”.
Is displayed (step 109a).

When the partial discharge to the ground is measured,
The maximum discharge charge is used as the trigger charge, and the coil is found by reducing the distance between the coupling capacitor and the current probe set in the non-partial discharge measurement phase one by one from both sides (steps 105 to 109c).

In the process of FIG. 11, first, m = 0, n
= (The number of U and V phase coils) (step 111),
Identify partial discharge between interlayer insulation and ground insulation (Step 1)
12). In the interlayer insulation partial discharge, since the polarity of the discharge current detected by all the current probes is the same, it can be distinguished from the ground insulation partial discharge. When the interlayer insulation partial discharge is measured, this search program displays a screen that recommends "Install a large number of current probes and specify the generated coil from the difference in the partial discharge pulse detection time of each current probe". The information is displayed on the device 530, and the process ends (step 119).

When the partial discharge to the ground is measured,
Using the maximum discharge charge amount as a trigger charge amount, the interval between the current probes installed in the coupling capacitor and the non-partial discharge measurement phase is divided into two while the interval between the current probes is reduced, and the corresponding coil is found (steps 113 to 118).

Note that both the processing of the flowchart shown in FIG. 10 and the processing of the flowchart shown in FIG.
In particular, when a high-frequency voltage is applied and the voltage is concentrated at the tap, since the partial discharge does not occur from the non-partial discharge measurement phase, the current probe on the opposite side of the coupling capacitor is connected to the neutral point. In this case, the number of search coils is reduced, and the coil having partial insulation against ground can be found at higher speed.

The calibration of the inter-layer insulation partial discharge charge amount is performed by a battery type.
Use a floating potential charge calibrator such as
Calibration charge in parallel with one coil via capacitance of insulating layer
Can be injected and calibrated. However, the amount of injected charge in this case
Calculates the charge calibrator display value as Q ₀, Charge calibrator series
The capacitance of the capacitor is C₀Of the insulation layer between the coils
Capacity C_sThen, the injected charge amount Q is equal to the first
In IL, Q = C_s/ (C₀+ C_s) Q₀ Becomes In other cases, Q = C_s/ (2C₀+ C_s) Q₀ Becomes

On the other hand, the calibration of the partial discharge charge amount to the ground insulation may be performed by injecting the calibration charge into the lead of the rotating electric machine as in the related art. However, it is desirable to perform calibration between each coil via the capacitance of the inter-coil connection insulating layer. In addition, in both the interlayer insulation and the ground insulation, in the equivalent circuit model of the rotating electric machine as shown in FIG. 2, a right angle capacitor in which a capacitor sufficiently smaller than each capacitance is connected in series in parallel with the interlayer insulation or the ground insulation of each coil in series. Calibration can also be performed by connecting a wave power supply. That is, the voltage generated in the discharge detection probe is calculated using EMTP or the like,
The voltage charge calibration coefficient may be obtained and calibrated from the ratio of the discharge charge amount obtained from the product of the square wave voltage and the capacitance of the capacitor connected to the square wave power supply to the voltage generated by the discharge probe.

Regarding the circuit constant of the equivalent circuit, the ground insulation capacitance C _g is obtained by measuring the capacitance between the coil conductor of one coil and the ground electrode grounded on the ground insulation surface by an impedance measuring instrument such as an LCR meter. Obtained by measuring. Further, the inductance L and the interlayer insulation capacitance C
_r is the impedance of the starting point and the ending point of the coil conductor of one coil, and the inductance L is obtained from the impedance and frequency on the lower frequency side than the resonance frequency of the inductance of the interlayer insulation and the ground insulation. it can be obtained an interlayer dielectric capacitance C _r.

The relationship between the shared voltage and the partial discharge characteristics of the interlayer insulation and ground insulation of each coil can be determined by installing a surface potential sensor at the connection between the coils and measuring the shared voltage, or by using an EMTP or the like to obtain an equivalent circuit of the rotating electric machine. It can be obtained by calculating the shared voltage of each part when a high-frequency voltage is applied to the model, obtaining the applied voltage of interlayer insulation and ground insulation, and comparing it with the partial discharge characteristics.

In the first embodiment, U-VW charging is performed,
Although the U-phase partial discharge was measured, insulation diagnosis of each phase can be performed by applying V-WU and W-UV charging. In particular,
In the extraction of the non-partial discharge measurement phase (in the first embodiment, the extraction of the V and W phases), the surge impedance of the coil is about (Equation 1)
It is desirable to connect an impedance of (100 to several kΩ) and connect it to the ground because the reflection oscillation of the partial discharge current can be suppressed. However, as long as the attenuation of the partial discharge in the rotating electric machine is large and the influence of the reflection is small, there is no problem whether it is directly grounded or not grounded.

In this embodiment, the test is performed for each phase. However, UV-W, VW-U, WU-V phase charging or U-V
A VW three-phase batch application may be applied, and a plurality of phases may be tested collectively.

In the diagnostic apparatus for interlayer insulation according to the first embodiment,
Although a high-frequency power supply of 200 kHz was used as the power supply, a voltage can be applied to a necessary place in the rotating machine by applying high-frequency voltages of various frequencies. In particular, when the voltage is concentrated on the coil near the outlet, the frequency of the power supply voltage is calculated using the inductance L of one coil, the interlayer insulation capacitance C _r , and the ground insulation capacitance C _g of FIG.

[0059]

(Equation 1) It is desirable that

[0060] If the circuit constant is not known, 1 measures the impedance between the start and end points of the coil conductors of the coils, it is possible to obtain the resonance frequency of the inductance L and the interlayer insulating capacitance C _r. By applying a high frequency higher than the obtained resonance frequency, almost the same result can be obtained. this is,
In a general rotating electric machine, the ground insulation capacitance C _g is smaller than the interlayer insulation capacitance C _r. Therefore, if the ground insulation capacitance C _g can be neglected, the above equation is equivalent to the inductance L of one coil. considered to become a parallel resonance frequency of the interlayer insulating capacitance C _r.

FIGS. 12A and 12B show examples of potential distribution measurement when the applied voltage frequency of a rotating electric machine having a resonance frequency of 100 kHz is changed. FIG. 12A shows the change of the coil-to-ground voltage with respect to the coil number from the outlet. On the other hand, FIG. 12B shows a change in the coil sharing voltage with respect to the coil number from the outlet. When diagnosing the interlayer insulation of all the coils at once, the power supply frequency should be lower than the resonance frequency and the voltage distribution should be made equal.

When a high-frequency voltage is applied, a large-capacity power supply is required because the charging current flowing through the capacitance of the ground insulation is large. However, testing with a large-capacity power supply is not preferable from the viewpoint of energy saving. For this reason, in the high-frequency power supply of the interlayer insulation diagnostic device of the present invention, as shown in FIG. Thus, the current capacity of the power supply can be reduced. Or, as shown in FIG. 13B,
By connecting the inductive load 31 in series and causing series resonance, the output voltage of the power supply can be reduced. In addition, the power supply capacity can be reduced by using an intermittent sine wave as shown in FIG. 14A instead of a continuous sine wave, and a waveform that attenuates with time as shown in FIG. 14B. . Furthermore, in addition to the high-frequency power supply, a surge power supply such as an impulse, a triangular wave, a rectangular wave, or an inverter power supply can be used as the power supply. In particular, since an inverter power supply can be used, the interlayer insulation diagnosis device of the present invention can be installed in a rotating electric machine, and interlayer insulation diagnosis can be performed even during inverter driving.

In the first embodiment, a surge power supply can be used in the interlayer insulation diagnosis device. Therefore, a conventional interlayer short-circuit test can be performed. Further, after the withstand voltage test of the interlayer insulation, it is possible to examine whether there is a coil having a short circuit between layers. However, in the conventional interlayer short-circuit diagnosis device, it is difficult to specify the interlayer short-circuit coil even if the existence of the interlayer short-circuit coil can be detected. However, in the interlayer insulation diagnostic apparatus according to the first embodiment, as described above, by measuring the voltage-current characteristics of each coil with the surface potential sensor and the discharge current sensor installed on each coil, The short-circuit coil can be specified.

FIG. 15 shows the voltage and current characteristics of the interlayer short-circuit coil and the sound coil. In the healthy coil 201, when the current flowing through the coil increases, the coil sharing voltage also increases in proportion to this. On the other hand, in the interlayer short-circuit coil 200, the generated voltage is smaller than that of the healthy coil, and the voltage is almost zero even if the current increases. This is because in the healthy coil 201, as shown in FIG. 16B, impedance is generated due to self-inductance. On the other hand, the interlayer short-circuit coil 20
At 0, as shown in FIG. 16A, a short-circuit current of (number of turns -1) times flows in a direction to cancel the input current in the closed circuit formed in the short-circuit portion, and becomes a state equivalent to a transformer of a secondary short-circuit,
The impedance drops significantly. For this reason, in the interlayer short-circuit coil 200, the generated voltage is smaller than that of the healthy coil, and the voltage does not increase even if the current increases.

In the first embodiment, a 100 pF capacitor is used as the coupling capacitor 6. However, it is desirable to use a capacitor having a large capacity because the partial discharge detection sensitivity is improved for both interlayer insulation and ground insulation. In particular, if the stray capacitance of the power supply line is almost equal to the capacitance of the coupling capacitor, the partial discharge detection sensitivity does not decrease even if the coupling capacitor is removed. Therefore, when the stray capacitance of the power supply line can be used, the size of the device can be reduced. As described above, when the coupling capacitor is not used, or when it is difficult to install the current probe on the ground line of the coupling capacitor, the current probe is installed on the power supply line.

In the present embodiment, the stray capacitance of the power supply line is connected in parallel with the ground insulation. By further inserting a capacitor in parallel, the partial discharge detection sensitivity of the interlayer insulation can be selectively improved. Therefore, when it is desired to selectively diagnose the interlayer insulation, it is desirable to insert a parallel capacitor.

As the current probe for detecting discharge used in the first embodiment, a Hall element type or a CT type can be used. In addition, a Rogowski coil, a high-frequency CT, or the like can be used.
In each case, the frequency band is 1 MHz or more, preferably 10 MHz.
Those having excellent high frequency characteristics of not less than MHz are desirable.

In this embodiment, a high-pass filter is used. However, when the power supply frequency is constant, a frequency cutoff filter called a notch, band rejection, band elimination filter or the like may be used. Further, when a filter having a sharp attenuation gradient is used, the cut-off frequency of the high-pass filter can be lowered and the frequency component of the partial discharge signal can be passed through more. It is desirable to use an analog or digital filter having an attenuation gradient of / oct or more. Since the background noise of the filter and the measuring instrument increases in proportion to √ (bandwidth), it is desirable to limit the frequency band of the filter and the measuring instrument to the band of the current probe or less.

In the first embodiment, a logic discriminator is used for discriminating between partial discharge in interlayer insulation and partial discharge in ground insulation. In addition, an analog circuit such as an adder or a subtractor can be used. That is, in Table 1,
The partial discharge of the interlayer insulation has the same polarity in the current probes 1 and 2,
Since the partial discharge of the ground insulation has the opposite polarity, the adder can output the partial discharge signal of the interlayer insulation and the subtractor can output the partial discharge signal of the ground insulation to the discharge detector 5. In particular, when detecting partial discharge of interlayer insulation, the current probe installed on the low voltage side of the coupling capacitor and the other current probes have the power supply frequency components of opposite polarity, while the partial discharge signal has the same polarity. Therefore, the power supply frequency component can be canceled by inserting an adder before the filter. Therefore, the cutoff frequency of the filter can be lowered,
More signal components can be passed. Adder,
As a subtractor, in addition to semiconductor circuits such as operational amplifiers,
A transformer with a divided winding can be used.

As the discharge detector 5, a high-speed analog / digital oscilloscope, a high-speed A / D converter, an impulse voltmeter or the like having a band equal to or larger than the band of the current probe can be used. In particular, digital oscilloscopes and A /
In the case of using a D converter, the logic discriminator and the filter circuit at the preceding stage can be substituted by a polarity discriminator, a logic gate, a digital filter function built in a digital oscilloscope or an A / D converter. Alternatively, data measured with a digital oscilloscope or A / D converter
The program may be transferred to a computer and subjected to logical discrimination and filtering by a program on the computer. That is,
The discharge detector 5 may be constituted by, for example, an information processing system 500 shown in FIG.

Although an induction motor is used as an object to which the above embodiment is applied, the present invention can be applied to an interlayer insulation diagnosis of other rotating electric machines such as a synchronous machine.

Next, a second embodiment of the present invention will be described. FIG. 17 shows an interlayer insulation diagnostic device according to the second embodiment. In this embodiment, instead of installing the current probe 2 at the inter-coil connection in the first embodiment described above, an electrode 40 is installed on the surface of the inter-coil connection insulating layer, and a ground voltage is applied between the electrode and the ground. A measuring capacitor 41 is inserted, and the inter-coil connecting portion conductor and the ground are capacitively coupled by the capacitance 42 of the inter-coil connecting portion insulating layer and the ground voltage measuring capacitor 41. The discharge current flowing to the ground is detected by the current probe 2.
However, in the polarity of the current probe in the second embodiment, the direction of the current flowing from the power supply side to the ground is positive.
In particular, in a rotating electric machine in which the neutral point is grounded, the current probe can be installed on the neutral point grounding line without capacitively coupling the connection between the coils and the ground. Also, for the extraction of the non-partial discharge measurement phase, a current probe can be installed on the ground wire connecting the extraction and the ground.

Also in this embodiment, the diagnosis support device 40
0, a coupling capacitor 6, and a test power supply 7 are used. The diagnosis support device 400 includes a multi-channel high-pass filter 3, a logical discriminator 4, and a discharge measuring device 5. In addition, the collection and processing of data and diagnosis can be realized by using the above-described information processing system.

The following is an explanation of the interlayer insulation diagnostic device of this embodiment.
The operation will be described. FIG. 18 shows the ladder of the induction motor coil.
Type equivalent circuit model and partial discharge of interlayer insulation and ground insulation
4 shows an electric current path. In the model shown in FIG.
As with the model, _rAnd a parallel circuit of L
And the discharge current path is shown. In this embodiment
Also, similarly to the first embodiment, the current probes 1 and 2 are simply connected.
If used alone, the partial discharge voltage for interlayer insulation and ground insulation
The flow cannot be determined. However, in the second embodiment
Is the current probe in the interlayer insulation partial discharge as shown in Table 4.
The polarity of 1 and 2 is opposite polarity, and the same polarity in partial insulation to ground.
Become.

[0075]

[Table 4] Accordingly, by determining the polarity of the partial discharge current detected by the current probes 1 and 2 by the logic discriminator 4 as in the first embodiment, it is possible to distinguish the partial discharge between the interlayer insulation and the ground insulation. However, in the present embodiment, since the discharge current polarities of the interlayer insulation and the ground insulation are opposite to those of the first embodiment, the truth table in Table 2 and the logical discrimination circuit in FIG. The criteria for insulation to ground are reversed.
Further, the use of the adder and the subtractor described in the first embodiment is reversed.

In the second embodiment, the interlayer insulating partial discharge generating coil is specified from the polarity of the partial discharge current, or
Partial discharge generated from a specific coil can be measured. This is because, in the second embodiment, as shown in Table 5, the discharge current polarities of the current probes provided at both ends of the interlayer insulating partial discharge generating coil are opposite to each other. This corresponds to the fact that the insulated partial discharge generating coil to the ground can be detected from the polarity of the partial discharge current in the first embodiment. Therefore, also in the second embodiment, by examining the discharge current polarity patterns of the plurality of current probes or by scanning while reducing the number of coils in the test block and finding the coil whose polarity is reversed, the interlayer insulation partial discharge generation coil Can be specified.

[0077]

[Table 5] As the search algorithm for specifying the partial discharge generating coil, the search algorithm according to the first embodiment shown in FIGS. 10 and 11, that is, the search algorithm used in the flowcharts shown in FIGS. it can.

As described above, in the second embodiment, since the interlayer insulation partial discharge generating coil can be specified, the coil in which the interlayer insulation has deteriorated can be detected and removed.
In the second embodiment, the ground-insulated partial discharge generating coil can be specified by measuring the delay of the time when the discharge current reaches each current probe after the ground-insulated partial discharge occurs.

In the second embodiment, since the capacitor 41 for measuring a ground voltage is provided, unlike the first embodiment, the capacitance of the capacitor 41 and the capacitance of the capacitor 41 do not need to be newly provided. Capacitance 4 of the insulating layer between the coils
The coil-to-ground voltage and the coil-sharing voltage can be measured by dividing the capacitance by 2. In addition, even if the electrode 40 provided on the surface of the insulating layer between the coils is directly connected to the ground without connecting the capacitor 41 for measuring the ground voltage, and the current probe 2 is installed on the connection wire, the interlayer insulation and the insulation can be obtained. Can distinguish between ground insulation. In this case, an edge discharge occurs at the electrode 40 provided on the surface of the inter-coil connection insulating layer. The edge discharge is suppressed by applying an electric field relaxing paint to the electrode end or by arranging the electric field relaxing electrode. it can.

In the case where discharge current detection is performed for two or more inter-coil connection portions by capacitive coupling between the inter-coil connection portion and the ground, the end discharge is distinguished from the interlayer discharge and the partial discharge of the ground insulation. it can. This is because, as shown in Table 6, the polarity of the discharge current of the current probe is reversed between the inter-coil connection portion where the end discharge occurs and the inter-coil connection portions located on both sides thereof. Therefore, by finding an inter-coil connection part having a partial discharge current having a different polarity from that of the current probe installed at the inter-coil connection part located on both sides, it is possible to specify an end discharge generation source and perform an electric field relaxation process. Note that this can be performed by identifying from the discharge current polarity patterns of the plurality of current probes installed as described above, or by performing scanning while reducing the number of coils in the test block.

[0081]

[Table 6] FIG. 19 shows a flowchart in which, when the procedure shown in FIG. 10 is used as a method for searching for an interlayer insulation partial discharge generating coil, an identification sequence of an end discharge generating coil is added. When the test block is initially large, the edge discharge is regarded as the same as the partial discharge to the ground, and can be distinguished from the partial discharge to the interlayer insulation. In addition, in the insulated partial discharge to the ground, since the polarities of all the current probes match, it can be distinguished from the end discharge. The procedure from steps 1901 to 1908 is described in FIG.
0 is common to the procedure shown in FIG. However, because of the difference in the installation of the probe, the retrieved result is the m-th coil interlayer insulation partial discharge (step 1909) and the (n + 1) th coil interlayer insulation partial discharge (step 1910). On the other hand, steps 1911 to 1920 are an identification sequence of the end discharge generating coil. Steps 1911 to 1915 are processed in the same procedure as steps 1903 to 1907. Then, in step 1915, when the discharge current polarity is equal between the current probe #m and the coil #n, it is determined whether or not the coil #n is (n = m + 1) (step 1916), and (n = m + 1) If so, it is determined that the partial discharge to the ground is insulated (Step 191
7). On the other hand, if the coil #n is not (n = m + 1), the process returns to step 1914.

Also in the search method corresponding to FIG. 11, after the identification of the ground insulation and the interlayer insulation partial discharge, the identification sequence of the ground insulation partial discharge and the edge discharge is added, whereby the interlayer insulation and the interlayer insulation partial discharge are added.
Discharge can be distinguished between partial discharge to ground and end discharge.

As the discharge current sensor of the second embodiment, a Hall element type, a CT type current probe, a Rogowski coil, and a high-frequency CT can be used as in the first embodiment. Alternatively, a resistor can be used. Also,
When measuring the amount of discharge charge instead of measuring the discharge current, the discharge charge sensor can use a CR detection circuit formed by a resistor and a capacitor, or an LCR detector formed by a resistor, a capacitor, and an inductance. Note that L
When the partial discharge is tuned and detected by the CR detector, the partial discharge can be measured with higher accuracy by further providing a tuning amplifier and a detection circuit between the logical discriminator and the discharge detector.

On the other hand, when the partial discharge is detected while measuring the ground voltage of the coil as in the second embodiment or the first embodiment, generally, as shown in FIG. If the phase of the ground voltage is −90 ° to 90 °, the discharge is positive. If the phase is 90 ° to 270 °, the discharge is negative. By the way, when a discharge occurs in the first coil as in the first and second embodiments, in the current probe 2, the discharge currents of the interlayer insulation and the ground insulation have opposite polarities. For this reason, if a logical discriminator that allows only a negative partial discharge pulse to pass from -90 ° to 90 ° and allows a positive partial discharge pulse to pass from 90 ° to 270 ° is used, partial discharge of interlayer insulation can be performed. Can be detected. If the polarity gate of the logic discriminator is reversed, a partial discharge of the ground insulation can be detected. Therefore, at least the current probe 1 provided on the ground line of the coupling capacitor can be removed.
At the same time, the coupling capacitor can be eliminated, and the device can be downsized.

Table 7 shows the voltage to ground, interlayer insulation, the discharge polarity of partial discharge to ground, and the polarity of the discharge current detected by the current probe 2. The current probe 2 detects a positive-polarity discharge current in the interlayer insulating positive-polarity discharge and a negative-polarity discharge current in the negative-polarity discharge. On the other hand, the partial discharge current to the ground insulation has the opposite polarity to the partial discharge current to the interlayer insulation. Therefore,-
90 ° -90 ° is “0”, 90 ° -270 ° is “1”,
Assuming that the positive polarity of the current detected by the current probe is “1” and the negative polarity is “0”, as shown in the truth table in Table 8, the interlayer insulation partial discharge is identified by Exclusive OR, and the ground insulation partial discharge is identified by the reverse. it can. However, in the output of Table 8, if true, "1" was set.

[0086]

[Table 7]

[Table 8] FIG. 21 shows a circuit example of a logic discriminator that distinguishes partial discharge between interlayer insulation and ground insulation based on the phase of the ground voltage and the discharge current polarity of the current probe 2. In the present logical discriminator, the discharge current signal of the current probe 2 and the ground voltage signal are compared with the ground potential by the comparator 210, and are converted into positive polarity signals and negative polarity signals of 5V and 0V, respectively. The polarity signal of the ground voltage is input to the delay circuit 211 to delay the phase by π / 2. As the delay circuit 211, for example, a monostable multivibrator can be used. The output of the delay circuit 211 is input to the exclusive OR circuit 212 together with the polarity signal of the current probe 2. The output of the exclusive OR circuit 212 is connected to the switch 2 when detecting the interlayer insulation partial discharge.
13 is input as a trigger of a switch 214 that is turned on at H level. On the other hand, when measuring the partial discharge to the ground, the output of the exclusive OR circuit 212 is
After that, the signal is input as a trigger of the switch 214. FIG. 20 shows an example in which an interlayer insulating partial discharge is extracted from a ground voltage waveform and a partial discharge pulse train.

FIG. 22 shows an interlayer insulation diagnostic apparatus according to the third embodiment. In the interlayer insulation diagnostic device according to the third embodiment, the current probe 2 of the inter-coil connection portion according to the first embodiment is used.
Is installed in the coil end portion 60 of the rotating electrical machine coil end portion opposite to the inter-coil connection portion. Hereinafter, the discriminating operation between the interlayer insulation and the ground insulation in the third embodiment will be described.

FIG. 23 shows an equivalent circuit model of one coil and partial discharge currents of interlayer insulation and ground insulation. 1 coil of the rotary electric machine is formed of a plurality of turns, the electrostatic capacitance c _r of the interlayer insulation between the winding turns is, the electrostatic capacitance c _g of ground insulation is present between turns and ground. Therefore, the equivalent circuit of FIG. 23 is established. On the other hand, the current probe 61 installed at the coil end portion is linked to all the turn conductors of one coil, and thus can be considered to be installed at each turn conductor. When a partial discharge occurs in such a coil, a partial discharge current flows through the path in FIG. That is,
In the high-frequency region, the impedance of the capacitance of the interlayer insulation is smaller than the inductance of the coil, so that the high-frequency partial discharge current flows through the capacitance of the interlayer insulation.
On the other hand, in the last turn, since the capacitance of the ground insulation is small, the partial discharge current also flows through the inductance of the coil. In fact, in Example 1, _{cr to} 1000 pF, L to
Since 0.1 mH and c _{g to} 100 pF, the above operation is satisfied when the detection frequency region of the partial discharge current is 1 MHz or more. On the other hand, the low-frequency partial discharge current propagates through the coil inductance, but is removed by the high-pass filter 3, so that it does not affect the determination of partial discharge between interlayer insulation and ground insulation. As a result, the partial discharge currents detected by the current probes 1 and 61 are as shown in Table 9,
As in the case of the first embodiment, partial discharge between interlayer insulation and ground insulation can be determined.

[0089]

[Table 9] However, the polarity of the current probe was such that the current flowing in the direction toward the output of the test phase outside the rotating electrical machine was positive, and the direction of the current flowing from the output of the test phase to the output of the other phase was positive inside the rotating electrical machine. As described in the operation of the first embodiment, in the present invention, in order to determine partial discharge of interlayer insulation and ground insulation of a coil sandwiched by current probes or a block including a plurality of coils, a third embodiment is described. In the embodiment, the detection area is shifted by half the coil from the first embodiment. Further, in the third embodiment, as in the first embodiment, the partial-discharge current generating coil is grounded based on the polarity of the partial discharge current.
An interlayer insulating partial discharge generating coil can be specified from the difference in current arrival time.

In the interlayer insulation diagnostic apparatus according to the third embodiment,
Similarly to the first embodiment, an interlayer short-circuit test can be performed to specify an interlayer short-circuit coil.

FIG. 24 shows current characteristics of the interlayer short-circuit coil and the sound coil. In the healthy coil 201, the current of the current probe also increases in proportion to the input current to the coil. Also,
This inclination substantially matches the number of turns of the coil. On the other hand, in the interlayer short-circuit coil 200, even if the current increases, the current is almost zero. This is because, as shown in FIG.
In 1, the current probe linked to the coil detects n × I current. In contrast, the interlayer short-circuit coil 20
At 0, as shown in FIG. 25A, the current (n−1) × I flowing through the remaining sound winding and the short-circuit current (n−1) I flowing in the direction to cancel the magnetic field generated by the input current are opposite. This is because the current probe is linked in the direction, and the current probe detection current becomes 0.

Next, the insulation deterioration diagnosis of the rotating electric machine is performed by using the above-described interlayer insulation diagnosis device, and
An example in which at least the coil is updated as necessary will be described. FIGS. 26 and 27 show an example in which the interlayer insulation diagnostic device of the first embodiment is installed to diagnose the interlayer insulation and the ground insulation of the induction motor. In the present embodiment, UVW three-phase collective charging is performed. In addition, the current probes 1 and 2 were installed on the power supply line of each phase and the connection between the coils, respectively. The output of each current probe 1, 2 is
Input to 0. In the interface device 540, the analog signal is converted into a digital signal by the multi-channel high-speed A / D converter 541, and after the power supply frequency component is removed by the built-in digital filter 542,
Send to computer 510.

The transmitted data is displayed on the partial discharge measurement result screen, as shown in FIGS. 6 to 9, and by operating the function key, the interlayer insulation and ground insulation partial discharge characteristics of each coil can be examined. it can. Further, by instructing the [diagnosis] icon 5312, the amount of discharged electric charge for which the coil has to be updated, for example, with respect to ground insulation, is described in “Generator Winding Insulation Deterioration Criteria” No. 67001 (1967-4), with regard to interlayer insulation, it is basically compared with non-partial discharge at a shared voltage during operation, and with respect to ground insulation and interlayer insulation partial discharge characteristics of each coil. In the case where a partial discharge generating coil exceeding the reference in ground voltage during operation is found in the ground insulation and a coil in which the partial discharge start / extinction voltage is lower than the shared voltage in the operation in interlayer insulation, the computer 51 is used.
0 is the display screen 53 of the display device 530 as shown in FIG.
00, a warning window 5340 is displayed, and a message 5341 warning the user is displayed in the window 5340.
Is displayed.

In this case, in the characteristic diagram display area 5330, the characteristic diagram selected by the icon group 5310, for example, in the example of FIG. 27, the left region 5331 includes FIG. Is displayed. In this figure, the coil is represented by a figure, for example, a square, and this is schematically shown in a state in which the squares corresponding to the respective phases of the UVW are connected by the number thereof and star-connected.
Then, the display mode of the graphic representing the coil having a problem in the insulation state is changed and displayed. Specifically, for example, highlighting such as thickening, changing the color, and blinking the frame line of the figure representing the coil is performed. Further, for each figure, similarly to the icon, the pointer MP is placed on the figure, and the selection of the coil represented by the figure is accepted by clicking the button of the mouse 522. In response to this, in the right area 5332 of the characteristic diagram display area 5330, a diagram showing the characteristics of the selected coil, in the example of FIG. 27, FIG. B-2 (coil maximum discharge charge-voltage characteristics) is displayed.

The values of the ground voltage and the inter-layer insulation voltage of each coil during operation are previously measured or calculated by a circuit calculation program such as EMTP, and stored in the computer. When the user of the induction motor finds a defective coil, the user instructs the [Contact] icon 5313, and the computer 510 contacts a manufacturer connected via a network. In an environment without a network, the telephone number displayed on the contact is called. Thereby, the coil is updated or the induction motor itself is updated.

[0096] By performing the above, proper operation can be performed without using an induction motor until the dielectric breakdown occurs. In particular, in the insulation diagnosis using the interlayer insulation diagnosis apparatus of the present invention, a coil having a defect in interlayer insulation, which has been difficult to find in the past, can be found. For this reason, compared to the past,
A more reliable induction motor can be provided.

FIG. 28 shows an example of diagnosing interlayer insulation and ground insulation of an induction motor using an inverter power supply.
In this embodiment, the induction motor 223 is connected to the inverter power supply 221 connected to the AC power supply 220 by the power cable 222. In the present embodiment, since the inverter power supply used for the operation of the induction motor is used directly, it is not necessary to measure or calculate the ground voltage and the interlayer insulation voltage of each coil particularly during the above-mentioned operation. For this reason,
Insulation diagnosis can be performed in a short time. In addition, U
When a three-phase alternating current is applied to VW, if the detection currents of the current probes installed in each coil of each phase of UVW are summed up with the same current probe installation position number from the lead, the power supply frequency components cancel each other, so partial discharge occurs. Can be more clearly detected.

Further, in the rotating electric machine equipped with the interlayer insulation diagnostic apparatus of the present invention, partial discharge can be measured even while the induction motor is operated by the inverter power supply, so that the deterioration state of the insulating layer is always grasped. be able to.

FIG. 29 shows an example of an induction motor in which the operation has been stopped because the maximum discharge charge amount of the ground insulation has increased rapidly. FIG. 30 shows an example in which a large void is generated in interlayer insulation due to vibration or thermal deterioration, and a partial discharge is suddenly detected. Note that the screen display method in FIGS. 29 and 30 is the same as that in FIGS. 7, 8, 9 and 27 described above.

As described above, according to the interlayer insulation diagnostic apparatus of the present invention, even in the rotating electric machine which has conventionally been rapidly deteriorated due to the operating condition and the like and has a danger of insulation breakdown during a blank period between the regular diagnostics, The operation can be stopped before the insulation breakdown to update the coil or the rotating electric machine main body. As described above, with the interlayer insulation diagnosis device of the present invention, it is possible to perform a diagnosis of the deterioration of the interlayer insulation between rotating electric machines and to provide a rotating electric machine with higher reliability than before.

The above insulation diagnosis system can be summarized as shown in FIG. That is, in the present insulation diagnosis system, the interlayer / ground insulation partial discharge measurement unit 112 connected to the rotating electric machine 118 and the power supply 141 capable of switching the type of power supply, voltage application phase, and the like, and the computer 510 for controlling the same are provided by: The communication line 111 and the interface device 540 are connected. The communication line 111 for transmitting and receiving commands, data, and the like includes, for example, GP-I
B, USB, RS-232C, a communication network and the like are used. Computer 51 used in the apparatus of FIG.
As 0, for example, a computer having a hardware system configuration shown in FIG. 37 can be used. Computer 51 realized by executing a program
The processing unit 511 that performs data processing includes an internal function of “0”.
0, a storage unit 5120 for performing data storage processing, and a display and input / output unit 5130 for performing display and input / output control
And a measuring device control unit 5140 that controls the measuring device.

The external storage device 514 managed by the storage unit 5120 stores data used for diagnosis. FIG. 33 shows an example thereof. Storage device 5
14 includes, for example, a data file 51 including data in the rotating electrical machine interlayer insulation diagnostic device.
41, and a data file 5142 including a user name, a delivery destination, a product model, specifications, a serial number, a manufacturing time, a delivery date, and the like.
And a drawing data file 5143 containing drawing data;
A data file 5144 having rotating electrical machine voltage distribution data during operation, a data file 5145 having ground / interlayer insulation partial discharge characteristic data, and a data file 5146 having ground / interlayer insulation partial discharge reference data are stored.

The processing section 5110 performs insulation diagnosis according to, for example, an operator's input command in accordance with the insulation diagnosis flowchart shown in FIG. That is, the partial discharge starting voltage V
i, the partial discharge extinction voltage Ve, and the maximum discharge charge amount Qma
ax is obtained (step 2001). Next, Qmax
Is greater than or equal to the reference discharge charge to ground insulation (step 2002). When Qmax is equal to or greater than the ground-discharge reference discharge charge, it is determined that “the coil or the rotating electric machine should be updated”. And a warning message 5 to that effect
341 is displayed in the warning window 5340 of the display screen 5300 of the display device 530 (step 2004).
On the other hand, when Qmax is less than the ground insulation reference discharge charge, it is determined whether Vi and Ve are each equal to or lower than the interlayer insulation sharing voltage. When Vi and Ve are each equal to or lower than the inter-layer insulation shared voltage, the process proceeds to step 2004, and the same processing as the above-described coating is performed. If not,
It is determined that the inspection has passed (step 2005).

Next, an example of determining whether or not a used rotating electric machine manufactured for a commercial frequency power supply or an old type inverter power supply can be driven by a new inverter and improving the same will be described with reference to FIGS. 34 and 35. In this example, not only the diagnostic apparatus of the present invention but also a rotating electric machine user 900 and an insulation diagnosis company 9
01, coil manufacture and renewal company 902, and inverter manufacturer 920. However,
In some cases, these parties may also serve as each other. The act between the parties involved here is the exchange of various information,
The computer systems of the respective parties can be connected via a communication line to perform information transmission and reception.
Progress management is performed in each computer system in accordance with the exchange of information between the parties.

In this example, the user 900 requests the inverter manufacturer 920 to install a new inverter. Also, when introducing the new inverter, the user 900 requests the insulation diagnosis company 901 to determine whether or not the new inverter can drive the used induction motor. Insulation diagnosis contractor 9
01, when the interlayer insulation diagnostic apparatus of the present invention is used by using a high-frequency voltage as a power supply, the interlayer insulation shared voltage at the time of driving a new inverter obtained by measurement or a circuit calculation program such as EMTP is inputted. Is measured. However, when using a power supply capable of outputting a surge voltage having the same waveform as the new inverter, for example, the same peak value and wave front length, this operation can be omitted.

When the interlayer insulation diagnostic apparatus displays a screen recommending the update of the coil or the rotating electric machine or a screen recommending the improvement of the inverter waveform as shown in FIG. Result 90
Report to 0. If necessary, the partial discharge onset / extinction voltage is also reported. If a surge power supply is used, the partial discharge start / disappearance voltage and wavefront length are also reported. As a result,
The user 900 requests the coil manufacturing and updating company 902 to manufacture and update the coil, or
20 is requested to improve the inverter waveform. When the coil policy and the renewal company 920 receive the request, after renewing the coil, the diagnosis is performed again, and it is confirmed that the warning screen is not displayed. When the inverter manufacturer receives the request, at least, for example, by increasing the wavefront length 130, reducing the switching voltage 131, or reducing the switching surge voltage 132 as shown in FIG. In the improved waveform, the inter-layer insulation sharing voltage is set to be lower than the inter-layer insulation partial discharge start / extinction voltage. As a result, a used rotating electric machine manufactured for a commercial frequency power supply or an old type inverter power supply can be safely operated with a new inverter.The detection of partial discharge and the diagnosis based on the detected data are performed separately. It may be performed by a device. For example, the system for detecting partial discharge is a configurable system that can be brought to the site, and diagnosis is performed on another computer, for example, a host computer. Diagnosis is, for example,
Data is accumulated by a system that detects partial discharge,
The diagnosis can be made offline in the host computer. In addition, a system for detecting partial discharge can be connected to a computer running on foot via a communication line to perform online diagnosis.

As described above, according to each of the embodiments described above, the insulation diagnosis of the rotating electric machine can be performed with higher reliability than in the related art. As a result, it is possible to present a warning message indicating that the coil or the motor needs to be updated as necessary. In particular, a more reliable rotating electric machine can be provided by installing the interlayer insulation diagnostic apparatus of the present invention in the rotating electric machine, measuring partial discharge even during operation, and diagnosing insulation deterioration.

Further, by using the above-described diagnostic technique,
Interlayer insulation and ground insulation Partial discharge characteristics data are compared with the coil rewind reference. If the partial discharge charge amount or the partial discharge start / disappearance voltage does not satisfy the standard, the coil or rotating electric machine is updated and the inverter waveform is improved. Notification of the necessity can be realized. Furthermore, it is possible to determine whether or not a used rotating electric machine manufactured for a commercial frequency power supply or an old type inverter power supply can be driven by a new inverter by using the above-described diagnostic technique. as a result,
By improving the coil of the rotating electric machine and the like and improving the waveform of the inverter, it is possible to use the motor more safely.

Further, the above system compares the interlayer insulation partial discharge characteristic data with the interlayer insulation shared voltage when an inverter surge is applied, and determines whether at least the shared voltage is higher than the partial discharge start or disappearance voltage, or the partial discharge characteristic. System that notifies that the coil or rotating electric machine needs to be updated and the inverter waveform needs to be improved when it is determined that the interlayer insulation has deteriorated to such an extent that it cannot withstand future operation due to the relationship between the voltage and the residual breakdown voltage. Can be realized by:

As described above, the diagnostic apparatus of the present invention can measure the partial discharge characteristics of the interlayer insulation and diagnose the deterioration of the interlayer insulation of the rotating electrical machine, thereby providing a highly reliable rotating electrical machine. It becomes possible. Further, with the diagnostic device of the present invention, it is possible to determine whether a used rotary electric machine manufactured for a commercial frequency power supply or an old type inverter power supply can be driven by a new inverter. And if necessary, it can be improved. As a result, a highly reliable rotating electric machine that can be safely driven and an inverter power supply can be realized.

[0111]

As described above, according to the present invention,
The insulation state can be diagnosed by distinguishing between the partial discharge in the interlayer insulation and the partial discharge in the ground insulation.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an interlayer insulation diagnostic device according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a ladder-type equivalent circuit model of the induction motor coil, and a partial discharge current path of interlayer insulation and ground insulation in the interlayer insulation diagnosis device of the first embodiment.

FIG. 3 is an explanatory diagram showing an operation of discriminating a partial discharge current waveform detected by a current probe by a logical discrimination circuit.

FIG. 4 is a block diagram showing an example of a configuration of a logical discriminator that can be used in the present invention.

FIG. 5A is a graph showing a delay in rising of a current pulse due to a delay in arrival time of an interlayer insulating partial discharge current;
FIG. 5B is an explanatory diagram showing a positional relationship between a coil and a current probe.

FIG. 6 is an explanatory diagram showing an example of a display screen showing a rotating electrical machine coil voltage distribution and a maximum discharge charge-voltage characteristic;

FIG. 7 is a graph showing a maximum discharge charge distribution of a rotating electric machine coil;
FIG. 5 is an explanatory diagram showing an example of a display screen showing a maximum discharge charge-voltage characteristic.

FIG. 8 is a diagram showing a maximum discharge charge distribution of a rotating electric machine coil;
Explanatory drawing which shows an example of a discharge occurrence frequency-discharge charge amount characteristic display screen.

FIG. 9 is an explanatory view showing an example of a rotating electric machine coil discharge occurrence frequency distribution, discharge occurrence frequency-voltage characteristic display screen.

FIG. 10 is a flowchart for specifying a partial discharge generating coil by changing the position of the current probe from the output of the partial discharge measurement phase and the output of the non-partial discharge measurement phase while reducing the number of coils one by one.

FIG. 11 is a flowchart for specifying a partial discharge generating coil by changing the position of the current probe while dividing the current probe position into two parts, namely, a partial discharge measurement phase and a non-partial discharge measurement phase.

12A is a graph showing a change in coil-to-ground voltage with respect to a coil number from an outlet when the power supply frequency is changed, and FIG. 12B is a graph showing a change in a coil sharing voltage with respect to the coil number from the outlet when the power supply frequency is changed. FIG.

FIG. 13A is a circuit diagram showing a circuit configuration for reducing the current capacity of a power supply by applying an inductive load to a rotating electric machine and a coupling capacitor in parallel and causing parallel resonance, and FIG. FIG. 2 is a circuit diagram showing a circuit configuration for reducing an output voltage of a power supply by applying an inductive load and causing series resonance.

14A is a waveform diagram illustrating a power supply capacity reducing method using an intermittent sine wave pulse, and FIG. 14B is a waveform diagram illustrating a power supply capacity reducing method using an attenuation waveform.

FIG. 15 is a graph showing the relationship between the current probe detection current of the interlayer short-circuit coil and the healthy coil and the coil sharing voltage.

16A is an explanatory diagram showing an equivalent circuit of an interlayer short-circuit coil, and FIG. 16B is an explanatory diagram showing an equivalent circuit of a sound coil.

FIG. 17 is a block diagram showing a configuration of an interlayer insulation diagnosis device according to a second embodiment of the present invention.

FIG. 18 is a circuit diagram showing a ladder-type equivalent circuit model of an induction motor coil and a partial discharge current path of interlayer insulation and ground insulation in the diagnostic apparatus of the second embodiment.

FIG. 19 is a diagram showing an interlayer insulating partial discharge and an end discharge generating portion by changing the position of the current probe while reducing the number of coils one by one from the partial discharge measurement phase and the non-partial discharge measurement phase. Flowchart.

FIG. 20 is a waveform chart showing the relationship between the phase of the ground voltage and the polarity of the partial discharge to the ground.

FIG. 21 is a diagram showing a phase of a ground voltage and a current probe 2;
FIG. 4 is a block diagram showing a configuration of a logical discriminator that distinguishes partial discharge between interlayer insulation and ground insulation based on the polarity of the discharge current.

FIG. 22 is a block diagram showing a configuration of an interlayer insulation diagnosis device according to a third embodiment of the present invention.

FIG. 23 is a circuit diagram showing a detailed equivalent circuit model of an induction motor and a partial discharge current path for interlayer insulation and ground insulation in the diagnostic apparatus of the third embodiment.

FIG. 24 is a graph showing a relationship between a coil input current of an interlayer short-circuit coil and a healthy coil and a current probe detection current.

FIG. 25A is an explanatory diagram showing that a current probe detection current of an interlayer short-circuit coil becomes 0, and FIG. 25B is an explanatory diagram showing an equivalent circuit of a sound coil.

FIG. 26 is a wiring diagram showing an example of insulation diagnosis of an induction motor using a high-frequency voltage.

FIG. 27 is an explanatory diagram showing an example of a display screen when a defect in interlayer insulation is found during insulation diagnosis.

FIG. 28 is an explanatory diagram showing an example of the position of an inverter-driven rotary electric machine in which an interlayer insulation diagnosis device is installed.

FIG. 29 is an explanatory view showing an example of a display screen when a rotating electrical machine in which the amount of partial discharge charge to ground insulation is suddenly detected by measuring partial discharge even during inverter operation.

FIG. 30 is an example in which a rotating electrical machine in which a partial discharge has suddenly occurred from interlayer insulation due to a failure is detected by measuring the partial discharge even during the inverter operation.

FIG. 31 is a block diagram showing a configuration example of a simplified insulation diagnosis system.

FIG. 32 is a flowchart showing a procedure of insulation diagnosis.

FIG. 33 is an explanatory diagram showing an example of the position of a data file of the insulation diagnosis system;

FIG. 34 is an explanatory diagram showing a procedure for taking measures against driving a used rotating machine by an inverter.

FIG. 35 is an explanatory diagram showing a procedure for taking measures for improving the waveform of the inverter that drives the rotating machine.

FIG. 36 is a waveform chart showing waveforms for improving a waveform of an inverter that drives a rotating machine.

FIG. 37 is a block diagram showing an example of a hardware system configuration of an information processing system used for processing for detecting and diagnosing partial discharge in the present invention.

FIG. 38 is a partially cut-away side view showing the structure of the rotating electric machine.

FIG. 39A is a perspective view showing a structure of a coil of the rotating electric machine, and FIG. 39B is a sectional view taken along line AA ′.

[Explanation of symbols]

Reference Signs List 1 current probe installed in coupling capacitor 2 current probe installed in connection between first coil and second coil 3 multi-channel high-pass filter 4 logic discriminator 5 discharge measuring instrument 6 coupling capacitor 7 test power supply 8 test Power supply internal impedance, protection resistance, blocking impedance 9 Power line 10 Induction motor 11 U-phase first coil 12 U-phase second coil 13 V-phase or W-phase first coil 14 U-phase first coil-second coil connection 15 U-phase second coil-third coil connection portion 16 Rotating electrical machine coil end portion connecting side coil 17 Non-connecting side between rotating electrical machine coil end portion coil 20 Interlayer insulating partial discharge 21 Ground insulating partial discharge 22 Interlayer insulating partial discharge current 23 Partial discharge current to ground insulation 24 Partial discharge current detected by current probe 1 25 Current probe 2 Partial discharge current detected in 2 26 Output signal of logical discriminator 27 Extraction of test phase 28 Extraction of other phase 30 Rotating electric machine and coupling capacitor 31 Coil 40 Electrode installed on insulating layer surface of connection between coils 41 Coil to ground voltage Capacitor for measurement 42 Insulation layer capacitance at connection between coils 50 Coil-to-ground voltage 51 Example of partial-discharge pulse train to ground insulation 60 Coil end part opposite to lead 61 Current probe installed at coil end opposite to lead 160 Rotating electric machine Coil 100 Rotary electric machine user 101 Insulation diagnostic company 102 Coil manufacture and update company 111 Command / data communication line 112 Interlayer / ground insulation partial discharge measuring unit 118 Rotary electric machine 120 Inverter manufacturer 130 Crest length 131 Switching voltage 132 Switching surge voltage 140 Insulation diagnosis Apparatus 141 Power supply 161 Coil outlet (in) 162 Coil outlet (out) 163 Ground electrode 170 Interlayer insulation 171 Coil conductor 172 Coil conductor bundle 173 Ground insulation 180 Rotator 181 Stator 182 Rotor 183 Stator slot 190 Comparator 191 Exclusive OR circuit 192 Inversion circuit 193 Interlayer insulation, ground insulation partial discharge switch 194 Gate switch 200 Interlayer short circuit coil 201 Healthy coil 210 Comparator 211 Delay circuit 212 Exclusive OR circuit 213 Interlayer insulation, ground insulation partial discharge changeover switch 214 Gate switch 215 Inversion circuit 220 AC Power supply 221 Inverter power supply 222 Power cable 223 Induction motor 230 Interlayer insulated partial discharge generating coil 231 Coils at both ends of interlayer insulated partial discharge generating coil The current probe 232 located at the connection between the coils on the power supply side at the connection between the coils, the current probe 233 located at the connection between the coils at the neutral point side at the connection between the coils at both ends of the interlayer insulation partial discharge generating coil The current probe located at the connection between the coils on the power supply side at the connection between the coils that is one away from the insulated partial discharge generating coil, and the neutral point side at the connection between the coils that is one away from the interlayer insulated partial discharge generating coil The current probe 235 located at the inter-coil connection part of the current source 235 The current probe located at the inter-coil connection part on the power supply side at two distances from the interlayer insulation partial discharge generation coil 236 Two from the interlayer insulation partial discharge generation coil A current probe located at a neutral point-side inter-coil connection part at a remote inter-coil connection part 500 Information processing system 5 10 computer 530 display device 540 interface device

Continued on the front page (72) Inventor Keiji Fukushi 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-term in Hitachi Research Laboratory, Hitachi Ltd. 2G014 AA15 AA16 AA18 AB06 2G016 BC02 BD01 BD11 BD15

Claims (23)

[Claims] In a method for diagnosing insulation of a rotating electric machine, a partial discharge current is detected and detected for a coil to be diagnosed behind a position where the presence or absence of partial discharge of the coil is to be detected when viewed from a power supply side. The polarity of the partial discharge current is determined, and based on the result, it is distinguished whether the partial discharge current is due to partial discharge due to interlayer insulation or to partial discharge due to ground insulation. Diagnostic method. 2. The method for diagnosing insulation of a rotating electric machine according to claim 1, further comprising detecting a partial discharge current at a lead portion of a coil of the rotating electric machine, and detecting a polarity of the detected partial discharge current and a rear position of the coil. Comparing the polarity of the partial discharge current detected in the above, based on the result, to distinguish whether the partial discharge current is due to partial discharge due to interlayer insulation, or due to partial discharge to ground insulation, Diagnosis method for insulation of rotating electrical machines. 3. The insulation diagnosis method for a rotating electric machine according to claim 2, wherein when a partial discharge current detected at a position behind the coil is detected at a connection portion between the coils, the polarity of the partial discharge current is determined by the polarity of the coil. A method for diagnosing insulation of a rotating electric machine, comprising: determining the polarity of a partial discharge current detected at a lead-out portion; in the case of the same phase, a partial discharge due to interlayer insulation; and in the case of a reverse phase, determining a partial discharge due to ground insulation. . 4. The method for diagnosing insulation of a rotating electric machine according to claim 2, wherein when the partial discharge current detected at a position behind the coil is detected between the ground and the ground, the polarity of the partial discharge current is determined by a lead portion of the coil. 3. A method of diagnosing insulation of a rotating electrical machine, characterized in that the polarity of the partial discharge current detected in step (a) is opposite to the partial discharge due to interlayer insulation when the phase is opposite, and when the phase is the same, it is determined as partial discharge due to ground insulation. 5. The method for diagnosing insulation of a rotating electric machine according to claim 1, wherein a polarity of a partial discharge current detected at a position behind the coil and a phase of a voltage applied to the coil are compared to determine a voltage applied to the coil. When the phase of the partial discharge current is −90 ° to 90 °, it is determined that the partial discharge current is positive if the polarity is interlayer insulation, and if the polarity is negative, the partial discharge is ground insulation. A method for diagnosing insulation of a rotating electrical machine, characterized in that if the polarity is negative, it is determined that the discharge is interlayer insulation, and if the polarity is positive, it is partial discharge of ground insulation. 6. An insulation diagnostic apparatus comprising: acquiring a polarity of a partial discharge current detected by a discharge current sensor, and distinguishing between partial discharge between interlayer insulation and ground insulation based on the acquired polarity of the partial discharge current. . 7. The insulation diagnostic apparatus according to claim 6, wherein a power supply line of a lead portion of the rotating electric machine, or a coupling capacitor connected to the power supply line, a connection portion between coils of the rotating electric machine, a neutral point, Acquire the polarity of the partial discharge current detected by the discharge current sensor installed in the power supply line of the other-phase tapping part, and any of the coupling capacitors connected to the power supply line of the other-phase tapping part, and An insulation diagnostic device that distinguishes partial discharge between interlayer insulation and ground insulation based on polarity. 8. The insulation diagnostic apparatus according to claim 6, wherein the power supply line of the lead portion of the rotating electric machine, or a coupling capacitor connected to the power supply line, and a connection conductor between the coils of the rotating electric machine and ground. Insulation diagnosis characterized by acquiring the polarity of a partial discharge current detected by a discharge current sensor installed in a capacitive coupling part and distinguishing partial discharge between interlayer insulation and ground insulation based on the polarity. apparatus. 9. The insulation diagnostic apparatus according to claim 6, further comprising obtaining a voltage waveform to the ground of the coil, and distinguishing partial discharge between interlayer insulation and ground insulation from the voltage waveform and the polarity of the discharge current. An insulation diagnostic device characterized by the above-mentioned. 10. The insulation diagnostic apparatus according to claim 6, wherein a power line of the lead portion of the rotating electric machine, or a coupling capacitor connected to the power line, and a coil end located on a side opposite to a connection side between the coils. An insulation diagnostic apparatus characterized in that a partial discharge of interlayer insulation and a partial discharge of ground insulation are distinguished based on a polarity of a partial discharge current detected by a discharge current sensor installed in a section. 11. A rotating electric machine having a plurality of coils mounted thereon, wherein a conductor between the coils connecting the coils and the ground are capacitively coupled, and a discharge current sensor is provided at the capacitively coupled portion. Rotating electric machine. 12. The rotating electric machine according to claim 11, wherein, when the neutral point is grounded, a discharge current sensor is provided on a neutral point ground wire at a connection portion between the coils corresponding to the neutral point. A rotating electric machine characterized by the above-mentioned. 13. The rotating electric machine according to claim 11, wherein a current probe, a Rogowski coil, a high-frequency CT, or a resistor is used as the discharge current sensor. Electric machine. 14. A method of measuring a voltage applied to a coil of a rotating electrical machine, wherein a voltage generated in a capacitive or resistive voltage divider is provided at a lead portion, and a voltage of a capacitive coupling portion between the coil and a ground is provided at a connection between coils. A method for measuring a voltage applied to a coil of a rotating electric machine, characterized by measuring the generated voltage. 15. An insulation diagnosis device for performing insulation diagnosis of a coil of a rotating electric machine, wherein a sensor for detecting a partial discharge current from a coil to be diagnosed, and a partial discharge current detected by the sensor are taken in and taken in. Determine the polarity of the partial discharge current, whether the partial discharge current is due to partial discharge due to interlayer insulation,
An insulation diagnosis device, comprising: a diagnosis support device that distinguishes whether the discharge is caused by partial discharge of ground insulation and displays a state of the partial discharge based on a result of the discrimination. 16. An insulation diagnosis device for performing insulation diagnosis of a coil of a rotating electrical machine, comprising: a sensor for detecting a partial discharge current from a coil to be diagnosed; and a partial discharge current detected by the sensor. Determine the polarity of the partial discharge current, whether the partial discharge current is due to partial discharge due to interlayer insulation,
A discriminator that distinguishes whether it is due to partial discharge of ground insulation, and an information processing system that takes in the discrimination result, compares it with a reference value stored in advance, determines whether it is abnormal, and outputs the result An insulation diagnostic device comprising: 17. The insulation diagnostic apparatus according to claim 16, wherein the information processing system includes a computer that performs data processing, a display device, and an input device that receives an input instruction. Regarding the coil, the coil is represented by a graphic, the connection state is schematically displayed on the display screen of the display device, and the display mode of the graphic representing the coil determined to be abnormal is changed to indicate that the insulation is abnormal. An insulation diagnostic device for displaying the presence of a fault. 18. The insulation diagnostic apparatus according to claim 17, wherein the computer, when receiving a selection instruction from the input device for a coil graphic displayed on a display device, determines a coil corresponding to the graphic. An insulation diagnostic apparatus, wherein a characteristic diagram is displayed on a display screen. 19. The method of claim 6, 7, 8, 9, 15, 16,
A rotating electrical machine having the insulation diagnosis device according to any one of claims 17 and 18, and capable of performing insulation diagnosis even during operation. 20. The method of claim 6, 7, 8, 9, 15, 16,
The insulation diagnostic apparatus according to any one of claims 17 and 18, wherein the sensor for detecting the discharge current includes a current probe,
An insulation diagnostic apparatus characterized by using one of a Rogowski coil, a high-frequency CT, and a resistor. 21. An insulation diagnosis method for a rotating electric machine, wherein a sensor for detecting a partial discharge current from a coil to be diagnosed is connected for each coil of the rotating electric machine or for each block including a plurality of coils. During the operation of the rotating electric machine, a partial discharge current detected by the sensor is captured, the polarity of the captured partial discharge current is determined, and whether the partial discharge current is due to partial discharge due to interlayer insulation or to the ground. It is characterized by discriminating whether it is due to partial discharge of insulation, determining whether there is an abnormality in interlayer insulation, comparing with a previously stored reference value, determining whether there is an abnormality, and outputting the result. A method for diagnosing insulation of a rotating electric machine. 22. A method for providing an insulation diagnosis service for a rotating electric machine, comprising: receiving a request for insulation diagnosis for the rotating electric machine, for each coil of the requested rotating electric machine, or for each block including a plurality of coils. Connect a sensor for detecting the partial discharge current from the coil to be diagnosed, during the operation of the rotating electrical machine, capture the partial discharge current detected by the sensor, determine the polarity of the captured partial discharge current, By discriminating whether the partial discharge current is due to partial discharge due to interlayer insulation or to partial discharge due to ground insulation, whether there is an abnormality in interlayer insulation is compared with a previously stored reference value, A method for providing an insulation diagnosis service for a rotating electrical machine, comprising: determining whether there is a motor; and outputting the result. 23. A method for providing an insulation diagnosis service for a rotating electric machine, comprising: receiving a request for a diagnosis as to whether or not an inverter can be operated for the rotating electric machine; For each block including, a sensor for detecting a partial discharge current from a coil to be diagnosed is connected, and during the operation of the rotating electric machine, the partial discharge current detected by the sensor is taken in, and the polarity of the taken-in partial discharge current is taken. To determine whether the partial discharge current is due to partial discharge due to interlayer insulation or to partial discharge due to ground insulation, to obtain information indicating the degree of interlayer insulation, based on the obtained information And a method of providing an insulation diagnosis service for a rotating electric machine, characterized by presenting an improved inverter waveform.