JP5767490B2 - Discharge detection method and discharge detection system - Google Patents

Description

  The present invention relates to a discharge detection method capable of detecting a discharge of a rotating electrical machine and a discharge detection system used in the method.

  In recent years, variable speed operation of an inverter motor has been frequently performed in order to efficiently use energy and from the viewpoint of energy saving.

  However, when the motor is driven by an inverter, the motor is exposed to a high voltage pulse with a short rise time (hereinafter referred to as an inverter surge voltage) due to impedance mismatch between the cable and the motor. For this reason, the inverter motor is exposed to a stronger electrical stress than in the case of a normal sine wave driving motor. When electrical stress is applied to the motor, the electric field strength between the air gaps in the insulating component increases, and partial discharge may occur.

  This partial discharge can erode the insulating components and eventually cause dielectric breakdown, which can render the motor inoperable. For this reason, even if a high surge voltage is applied to the inverter motor, it is necessary to design the inverter so that partial discharge does not occur between the motor insulating portions, for example, winding turns. In addition, it is necessary to manufacture an insulating part based on the insulation design, inspect the motor insulation performance before shipment, and to ensure that defective products are not shipped under thorough partial discharge management.

  As a method for detecting the partial discharge in the inverter motor with high sensitivity, those disclosed in Patent Document 1 and Patent Document 2 are known.

JP 2009-288250 A JP 2005-69745 A

  However, in many cases, the detection method as described above cannot specify the position of occurrence of partial discharge in the inverter motor. For this reason, it is difficult to specify the manufacturing process of the poor insulation part.

  In Patent Document 1, since partial discharge detection is measured by current, it is often impossible to specifically specify the position of occurrence of partial discharge in the inverter motor. Furthermore, since a motor determined to be defective is usually disassembled and discarded, this may increase additional material costs and man-hours.

  On the other hand, in Patent Document 2, there is a possibility that a desired insulation failure location cannot be specified due to fluctuations in electromagnetic waves due to partial discharge.

  This invention is made | formed in view of this situation, The objective is to enable it to identify the insulation defect site | part of the insulation part of the stator of a rotary electric machine.

In order to achieve the above object, a discharge detection method according to the present invention includes a stator coil, a stator core in which a plurality of slots into which the stator coils are inserted are formed in the circumferential direction, at least an inner surface of the slot, and the In a discharge detection method for detecting a discharge generated in the insulating portion of the stator for a rotating electrical machine having an insulating portion that insulates from the conductor surface of the stator coil, a predetermined amount is provided on the insulating portion of the stator coil. A coil connection step for connecting voltage to be applied; an application step for applying a predetermined voltage to the stator coil after the coil connection step; and a shaft of the rotating electrical machine stator during the application step. Based on the first discharge detection step for detecting the discharge generated in the insulating portion and the discharge detected in the first discharge detection step, with a pair of axial antennas arranged on both sides in the direction, An axial position specifying step for specifying the axial position of the discharge and a predetermined axial position of the stator for a rotating electrical machine are arranged in the circumferential direction with a circumferential interval between them during the application step. A plurality of circumferential antenna devices that detect the discharge generated in the insulating portion in parallel with each other, and the discharge detected based on the discharge detected in the second discharge detection step. And a circumferential position specifying step for specifying the circumferential position.

Further, the discharge detection method according to the present invention includes a stator coil, a stator core in which a plurality of slots into which the stator coil is inserted is formed in the circumferential direction, at least an inner surface of the slot, and a conductor of the stator coil. In a discharge detection method for detecting a discharge generated in the insulating portion of the stator for a rotating electrical machine having an insulating portion that insulates from the surface, a predetermined voltage is applied to the insulating portion of the stator coil A coil connection step for connecting, an application step for applying a predetermined voltage to the stator coil after the coil connection step, and a circumferential interval with each other during the application step. a circumferential antenna unit group composed if either a plurality of antenna devices, a plurality arranged at predetermined axial intervals, said a plurality of antenna devices, the discharge from each other at the same time parallel to occur by the insulating portion A discharge detection step of detecting and, on the basis of the discharge detected by the discharge detection step, and having a axial position specifying step of specifying each of the axial position and circumferential position of the discharge.

The discharge detection system according to the present invention includes a stator coil, a stator core in which a plurality of slots into which the stator coil is inserted is formed in the circumferential direction, at least the inner surface of the slot, and the stator coil. In a discharge detection system for measuring a discharge generated in the insulating portion of the stator for a rotating electrical machine having an insulating portion that insulates between the conductor surfaces, each of the rotating electrical machine stators is disposed on both sides in the axial direction, A pair of axial antenna devices capable of sensing electromagnetic waves radiated by electric discharge, and electromagnetic waves radiated by electric discharge disposed at circumferential positions at predetermined circumferential positions at a predetermined axial position of the rotating electric machine stator. and a plurality of circumferentially antenna apparatus capable sensed simultaneously in parallel with one another, each electrically connected to the pair of axial antenna device and each circumferential direction antenna device And at least one of the pair of axial antenna devices and each of the circumferential antenna devices has a signal reading device configured to be able to input an electrical signal indicating that when discharge is detected. It is characterized by.

The discharge detection system according to the present invention includes a stator coil, a stator core in which a plurality of slots into which the stator coil is inserted is formed in the circumferential direction, at least the inner surface of the slot, and the stator coil. In a discharge detection system for measuring a discharge generated in the insulating part of the stator for a rotating electrical machine having an insulating part that insulates from the surface of the conductor, each can sense an electromagnetic wave radiated by the discharge and be circumferential with respect to each other An antenna device group comprising a plurality of antenna devices arranged in the circumferential direction at intervals and capable of sensing simultaneously in parallel with each other, and a plurality of antenna devices arranged at predetermined axial intervals, and the antennas When electrically connected to a device and at least one of the antenna devices senses a discharge, an electric signal indicating that fact can be input. And having a No. reading device.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to identify the insulation defect site | part of the insulation part of the stator of a rotary electric machine.

It is a block diagram showing typically the composition of the discharge detection system of a 1st embodiment concerning the present invention. It is a schematic perspective view which shows typically the state which arranged the 1st-8th circumferential direction antenna apparatus of FIG. It is a top view of the 5th circumferential antenna apparatus of FIG. FIG. 2 is a connection diagram illustrating a connection state of the stator coil and the like of FIG. 1. It is a graph which shows the waveform obtained by measuring with the applied voltage measurement part of FIG. 1, and the waveform of the partial discharge obtained with the discharge detection apparatus. It is a graph which shows the voltage waveform obtained with the 1st and 2nd axial direction antenna apparatus of FIG. It is a graph which shows the voltage waveform etc. which are obtained with the 1st-8th circumferential direction antenna apparatus of FIG. It is a connection diagram which shows the connection state of the coil of the discharge detection system of 2nd Embodiment which concerns on this invention. It is a block diagram which shows typically the structure of the discharge detection system of 3rd Embodiment which concerns on this invention. FIG. 10 is a connection diagram illustrating a connection state of the stator coil and the like of FIG. 9. FIG. 10 is a schematic diagram of a U-phase coil in FIG. 9. It is a connection diagram which shows the modification of FIG. It is a schematic perspective view which shows typically the arrangement | sequence of the circumferential direction antenna apparatus of the discharge detection system of 4th Embodiment which concerns on this invention.

  Hereinafter, embodiments of a discharge detection system and a discharge detection method according to the present invention will be described with reference to the drawings.

[First Embodiment]
A first embodiment will be described. FIG. 1 is a block diagram schematically showing the configuration of the discharge detection system of the present embodiment. FIG. 2 is a schematic perspective view schematically showing a state in which the first to eighth circumferential antenna devices 71 to 78 of FIG. 1 are arranged. FIG. 3 is a plan view of the fifth circumferential antenna device 75 of FIG. FIG. 4 is a connection diagram showing a connection state of the stator coil 32 and the like of FIG.

FIG. 5 is a graph showing a waveform obtained by measurement with the voltage detector 16 of FIG. 1 and a partial discharge waveform obtained with the partial discharge detector 14. FIG. 6 is a graph showing voltage waveforms (HA ₁ , HA ₂ ) obtained by the first and second axial antenna devices 61, 62 of FIG. FIG. 7 is a graph showing voltage waveforms and the like obtained by the first to eighth circumferential antenna devices 71 to 78 of FIG.

  First, the configuration of the discharge detection system of this embodiment will be described. This system can detect a partial discharge generated in an insulating portion (not shown) of the stator 30 of the rotating electrical machine, and detects a partial discharge generated between two phases (out of different phases) of the three-phase coils. is there.

  This system includes an AC power supply device 10, a stator installation unit 12 for installing a stator 30 of a rotating electrical machine, and a partial discharge detection device 14. In addition, this system includes two axial antenna devices, that is, a first axial antenna device 61 and a second axial antenna device 62, a set of circumferential antenna device groups 70, and these antenna devices. A first oscilloscope 51 and a second oscilloscope 52 for reading and confirming the detected discharge signal; The system also includes a voltage detection device 16 and a grounding switch Sg.

  The AC power supply device 10 can generate a predetermined AC voltage Vt and can be electrically connected to a connection unit 36 described later.

  The voltage detection device 16 is configured to be able to measure a voltage value generated in the AC power supply device 10.

  The partial discharge detection device 14 outputs a signal based on the partial discharge generated in the motor, and can determine whether or not the partial discharge is generated in the stator 30. In this example, it is possible to detect a partial discharge generated when an AC voltage Vt is applied to a stator coil 32 described later.

  A stator 30 of a rotating electrical machine that is a target of discharge detection using the discharge detection system of the present embodiment includes a stator coil 32, a stator core 34, and an insulating portion (not shown).

The stator coil 32 constitutes a U-phase, V-phase, and W-phase coil, and a connection portion that can be wired to a wire electrically connected to the AC power supply device 10, for example, at the coil end of each phase. 36 is formed. Each phase respectively connectable coil ends to another wiring, to form a U ₁ connection portion at one end of the coil of the U phase to form a U ₂ connecting part on the opposite side. Similarly, a V ₁ connection and a V ₂ connection are formed at each end of the V-phase coil, and a W ₁ connection and a W ₂ connection are formed at each end of the W-phase coil. Is done. A connection method for detecting a partial discharge generated between different phases (in this example, between the U phase and the V phase) will be described later.

  The stator core 34 has a substantially cylindrical shape formed by laminating a plurality of steel plates, and a through portion 35 penetrating in the axial direction is formed inside. A rotor (not shown) is disposed in the through portion 35. A plurality of slots (not shown) are formed on the inner surface of the through portion 35 of the stator core 34 so as to open radially inward and into which the stator coil 32 can be inserted. The slots are formed at equal intervals in the circumferential direction. The stator core 34 can be electrically grounded and is configured to be grounded when the grounding switch Sg is closed.

  As an insulating part, the insulation part between the ground which insulates between each inner surface of each slot and the conductor surface of the stator coil 32, the insulation part between different phases which insulates between the stator coils of a different phase, and a stator coil There is an inter-turn insulation that insulates between the internal turns. After forming these insulating portions, the stator coil is dried and cured by vacuum impregnation and dipping treatment with a varnish made of epoxy or polyester resin together with the stator.

  The first axial antenna device 61 is disposed on the motor connection side (left side in FIG. 1) outside the stator 30 in the axial direction. The second axial antenna device 62 is disposed outside the stator in the axial direction and on the side opposite to the motor connection (right side in FIG. 1). These first and second axial antenna devices 61 and 62 are of a horn antenna type, and can detect an electromagnetic wave radiated by a partial discharge generated in an insulating portion.

  The circumferential antenna device group 70 includes eight circumferential antenna devices, that is, first to eighth circumferential antenna devices 71 to 78.

  The first circumferential antenna device 71 is of a loop antenna type having a predetermined diameter D arranged in the through portion 35 of the stator 30 (FIG. 3). Each of the second to eighth circumferential antenna devices 72 to 78 is of a loop antenna type, similar to the first circumferential antenna device 71, and can detect electromagnetic waves radiated by partial discharge generated in the insulating portion. It is.

These first to eighth circumferential antenna devices 71 to 78 are arranged at predetermined axial positions in the circumferential direction at equal intervals (FIG. 2). Moreover, these 1st-8th circumferential direction antenna apparatuses 71-78 are integrally movable in an axial direction.

  In the first oscilloscope 51, the first and second axial antenna devices 61 and 62 are electrically connected to each other, and partial discharges detected by the first and second axial antenna devices 61 and 62 are detected. Such electrical signals can be input.

  The first oscilloscope 51 is electrically connected to the partial discharge detection device 14. A signal relating to the partial discharge detected by the partial discharge detection device 14 can be input.

  In the second oscilloscope 52, the first to eighth circumferential antenna devices 71 to 78 can be electrically connected to each other, and the partial discharges detected by the first to eighth circumferential antenna devices 71 to 78 are connected. It is possible to input an electrical signal related to. The second oscilloscope 52 can be electrically connected to the first oscilloscope 51.

  Details of the electrical wiring of the first and second oscilloscopes 51 and 52 are omitted.

  Here, a connection method for detecting a partial discharge generated between the U phase and the V phase will be described.

With the U ₁ connection portion as the high voltage side and the V ₁ connection portion as the ground side (FIGS. 1 and 4), the AC voltage Vt is connected between the U ₁ connection portion and the V ₁ connection portion. Moreover, the U ₂ connection part, the V ₂ connection part, and the W ₂ connection part are in an open state. The motor stator is electrically disconnected from the ground by a grounding switch Sg or the like. Thereby, the connection for detecting the partial discharge generated between the U phase and the V phase is completed.

  Next, a procedure for detecting a partial discharge generated between the U phase and the V phase using the partial discharge detection device 14 will be described.

First, the stator 30 is installed in the stator installation part 12, and it connects as shown in FIG. In this state, a predetermined AC voltage Vt is applied. The AC voltage Vt is a sine wave indicated by the voltage waveform _VAC shown in FIG. This voltage waveform _VAC is a voltage measurement value obtained by the voltage detector 16.

  The value of the AC voltage Vt is the same as the inverter surge voltage that appears at the motor end when the inverter is driven, and the peak-to-peak voltage value is the same, and is multiplied by a safety factor that takes into account processing failures and power supply voltage fluctuations in the actual machine. The voltage value. Usually, if the partial discharge start voltage of the actual machine is equal to or higher than Vt, the partial discharge is not detected, and the insulation of the model is determined to be acceptable.

On the other hand, when the partial discharge occurs in the insulating portion of the stator 30 when the AC voltage Vt is applied, the partial discharge detection device 14 detects this partial discharge. In this case, the pulse waveform V _IP due to the partial discharge as shown in FIG. 5 occurs.

  After confirming that the partial discharge has occurred in the insulating portion of the stator 30, the axial position and the circumferential position of the partial discharge are specified. First, the process of specifying the axial position will be described.

  First, the first and second axial antenna devices 61 and 62 are arranged on both sides of the stator 30 in the axial direction. In this state, the AC power supply 10 applies the AC voltage Vt to the stator coil 32 to generate a partial discharge as shown in FIG.

The graph of FIG. 6 shows voltage signals obtained by the first and second axial antenna devices 61 and 62, the horizontal axis is time, and the vertical axis is the voltage obtained by each antenna device 61 and 62. . The upper waveform (waveform HA ₁ ) in the graph of FIG. 6 is a voltage signal obtained by the first axial antenna device 61, and the lower waveform (waveform HA ₂ ) is the second axial antenna device. 62 is a voltage signal obtained at 62.

The waveform HA ₁ has a direction from the point of time zero (intersection of the vertical axis and the horizontal axis in FIG. 6) from the left to the right in FIG. 6 away from the first axial antenna device 61 (FIG. 1). To the right). In the waveform HA ₂ , the direction from the time zero to the left to the right in FIG. 6 corresponds to the direction farther from the second axial antenna device 62 (the left direction in FIG. 1). That is, the horizontal axis (time axis) in FIG. 6 corresponds to the axial position of the stator 30. For this reason, the axial position can be specified from the waveform HA ₁ and the waveform HA _{2 as} follows.

In FIG. 6, the waveform HA ₁ has a maximum voltage value V _P1 (peak) in a portion surrounded by a broken line in FIG. 6. Further, the waveform HA ₂ has a maximum voltage value V _P2 (peak) in a portion surrounded by a broken line. These peaks V _P1 and V _P2 are caused by partial discharge. Comparing these peaks V _P1 and V _P2 , it can be confirmed that the phase of V _P1 is advanced by τ in time with respect to V _P2 . This phase difference τ represents the time difference until electromagnetic waves emitted from the discharge source reach HA ₁ and HA ₂ . In addition, it can be seen that the strength _{V P1} is greater than _{V P2.} The difference in intensity includes information on the distance from the discharge source, and together with the time difference, the position in the axial direction of the partial discharge occurrence location can be specified from these information.

In FIG. 6, V _P1 detects a signal earlier than V _P2 , and as a result, it can be specified that the position where the partial discharge occurs is slightly on the left side of the motor. Incidentally, if the difference in the intensity and time difference of V _P1 and V _P2 does not occur, it can be identified as those discharge source occurs in the central portion of the rotating machine.

  Next, the process of identifying the circumferential position where partial discharge occurs at the axial position identified by the above procedure will be described.

  First, the first to eighth circumferential antenna devices 71 to 78 are arranged at the specified axial position, that is, a position slightly to the left of the axial center of the stator 30. Thereafter, the first to eighth circumferential antenna devices 71 to 78 are electrically connected to the first oscilloscope 51, and the waveforms obtained from the first to eighth circumferential antenna devices 71 to 78 are observed. Make it possible.

The graph of FIG. 7 displays the waveforms obtained by the first oscilloscope 51 collectively, with the horizontal axis representing time and the vertical axis representing voltage. This graph shows a voltage signal obtained by the first axial antenna device 61 described in FIG. 6 and a voltage signal obtained by the first to eighth circumferential antenna devices 71 to 78. Loop numbers 1 to 8 and waveforms R ₁ to R _{8 in} FIG. 7 correspond to the first to eighth circumferential antenna devices 71 to 78, respectively.

In Figure 7, of the waveform _{R 1} ~ waveform _{R 8,} the maximum voltage value appears in the waveform _{R 2.} Further, the waveform R ₁ and waveform R _3, peak slightly smaller has appeared than the maximum voltage value of the waveform R _2. The maximum voltage value of the waveform R ₃ is slightly greater than the maximum voltage value of the waveform R _1.

In addition, the waveforms R ₄ to R ₈ are almost no noise and peaks due to partial discharge are not recognized. That is, when viewed from the maximum voltage value, a relationship of R ₂ > R ₃ > R ₁ is recognized.

In this case, it can be seen that partial discharge has occurred near the circumferential position where the second circumferential antenna device 72 is disposed. Further, from the relationship between the maximum voltage values of the waveform R ₃ and the waveform R ₁ , the circumference in which the third circumferential antenna device 73 is arranged is slightly more than the circumferential position in which the second circumferential antenna device 72 is arranged. It can be identified that a partial discharge has occurred in the direction position.

  As can be seen from the above description, according to the present embodiment, it is possible to specify the axial position and the circumferential position of the partial discharge generated between different phases. Thereby, it is possible to specify a process in which a defect has occurred in a plurality of manufacturing processes for manufacturing the insulating portion. In the present embodiment, the discharge start voltage between the U phase and the V phase is Vt or less. Therefore, if the insulation location resulting from the site specified in this process and the manufacturing process are corrected, the rotating machine has a discharge start voltage equal to or higher than Vt and can be shipped.

  In addition, in this embodiment, between the different phases other than between the U phase and the V phase, between the V phase and the W phase, and between the W phase and the U phase, similarly to the detection between the U phase and the V phase. Partial discharge can be detected.

[Second Embodiment]
A discharge detection system according to the second embodiment will be described with reference to FIG. FIG. 8 is a connection diagram illustrating a connection state of coils in the discharge detection system of the present embodiment. In addition, this embodiment is a modification of 1st Embodiment (FIGS. 1-7), Comprising: The same code | symbol is attached | subjected to the same part or similar part as 1st Embodiment, and duplication description is carried out. Omitted.

  The configuration of the discharge detection system of this embodiment is the same as that of FIG. 1 described in the first embodiment.

  The discharge detection system of this embodiment can detect a partial discharge generated in the insulating portion of the stator 30 of the rotating electrical machine, and detects a partial discharge generated between each of the three-phase coils and the ground. In this example, a connection method for detecting a partial discharge generated between the U phase and the ground will be described.

The U ₁ connection portion connected to the AC power supply 10 as a high pressure side. Further, the V ₁ connecting portion and the W ₁ connecting portion are connected to each other and grounded (FIG. 8). At this time, the grounding switch Sg is closed.

Moreover, the U ₂ connection part, the V ₂ connection part, and the W ₂ connection part are in an open state. Thereby, the connection for detecting the partial discharge generated between the ground in the U phase is completed.

  The axial position and the circumferential position where the partial discharge occurs can be detected by the same procedure as in the first embodiment.

  It is also possible to detect partial discharges that occur between the V-phase and W-phase grounds.

[Third Embodiment]
A discharge detection system according to a third embodiment will be described with reference to FIGS. FIG. 9 is a block diagram schematically showing the configuration of the discharge detection system of the present embodiment. 10 is a connection diagram showing a connection state of the stator coil 32 and the like of FIG. FIG. 11 is a schematic diagram of the U-phase coil of FIG. FIG. 12 is a connection diagram illustrating a modification of FIG.

  In addition, this embodiment is a modification of 1st Embodiment (FIGS. 1-7), Comprising: The same code | symbol is attached | subjected to the same part or similar part as 1st Embodiment, and duplication description is carried out. Omitted.

  The discharge detection system of the present embodiment is capable of detecting a partial discharge that occurs in the insulating portion of the stator 30 of the rotating electrical machine, and detects a partial discharge that occurs between the turns of each of the three-phase coils. This system includes an impulse generator 20 and a power source selection switch Sv in addition to the components of the system (FIG. 1) described in the first embodiment.

  The impulse generator 20 is a device capable of generating an impulse signal having a predetermined voltage intensity. The rise time of the impulse generator 20 is about 1 μs or less. One of the impulse generator 20 and the AC power supply device 10 is electrically connected to the partial discharge detection device 14 by a power supply selection switch Sv.

  The impulse generator 20 is electrically connected to the connection portion 36 of the stator coil 32 by electrically connecting the impulse generator 20 and the partial discharge detector 14 by the power source selection switch Sv.

  Here, a connection method for detecting a partial discharge generated between turns in the U phase will be described.

The impulse generator 20 and the partial discharge detector 14 are electrically connected by the power source selection switch Sv, and the U ₁ connection is electrically connected to the impulse generator 20. Further, the V ₁ connection portion is grounded and the W ₁ connection portion is opened (FIG. 10). At this time, the grounding switch Sg is closed. Further, the U ₂ connection part, the V ₂ connection part, and the W ₂ connection part are connected to each other. Thereby, the connection for detecting the partial discharge generated between the turns in the U phase is completed.

The U phase of the stator coil 32 is wound around the stator core 34 so as to straddle a plurality of slots. When the U phase is schematically represented by one turn as one turn, the U phase is composed of a plurality of turns (U _t1 , U _t2 ,... U _tx in FIG. 11).

  Although illustration is omitted, the V phase and the W phase are also configured by being wound around a plurality of like the U phase.

When an impulse signal having a predetermined voltage intensity (Vt in this example) is applied between the U phase and the ground portion in the connection state shown in FIG. 10, between the input side and the output side of U _t1 in FIG. The voltage load acting during one turn is increased. Here, it is detected whether or not partial discharge occurs.

  The axial position and the circumferential position where the partial discharge occurs can be detected by the same procedure as in the first embodiment.

  With this configuration, it is possible to detect a partial discharge that occurs between turns in the U phase, and to specify an axial position and a circumferential position where the partial discharge occurs.

In addition, as shown in FIG. 12, even if the V ₁ connection portion and the W ₁ connection portion are connected to each other and grounded, the grounding switch Sg is closed and an impulse voltage is applied between them and the U phase, A partial discharge in between can be detected. Similarly, it is also possible to detect a partial discharge that occurs between the V-phase and W-phase turns.

  In the connection shown in FIG. 12, even if the grounding switch Sg is opened, the partial discharge between the U-phase turns can be detected. In this case, it should be noted that the voltage applied between the U-phase turns is reduced to 2/3 times as compared with the case of configuring the connection of FIG. Similarly, it is also possible to detect a partial discharge that occurs between the V-phase and W-phase turns.

[Fourth Embodiment]
A discharge detection system according to a fourth embodiment will be described with reference to FIG. FIG. 13 is a schematic perspective view schematically showing the arrangement of the circumferential antenna devices 71 to 78 of the discharge detection system of the present embodiment. In addition, this embodiment is a modification of 1st Embodiment (FIGS. 1-7), Comprising: The same code | symbol is attached | subjected to the same part or similar part as 1st Embodiment, and duplication description is carried out. Omitted.

  The configuration of the discharge detection system of this embodiment is the same as that of FIG. 1 described in the first embodiment.

  In the discharge detection system of the present embodiment, the first to eighth circumferential antenna devices 71 to 78 are used as one circumferential antenna device group 70, and the circumferential antenna device group 70 is placed in the through portion 35 of the stator 30. In addition, a plurality are arranged at predetermined axial intervals.

  Accordingly, it is possible to specify the axial position where the partial discharge occurs without using the first and second axial antenna devices 61 and 62. Accordingly, space can be saved as compared with the first embodiment.

[Other Embodiments]
The description of the above embodiment is an example for explaining the present invention, and does not limit the invention described in the claims. Moreover, each part structure of this invention is not restricted to the said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim.

In the connection method of the second embodiment, the discharge generation position between the stator coil and the ground is measured for each phase, and the partial discharge generation position is easy to narrow down. For example, the discharge detection described in the second embodiment In the system, the U ₁ connection, the V ₁ connection, and the W ₁ connection may be connected to each other, and a voltage may be applied between these and the ground.

  Even if the discharge detection system (FIG. 9) described in the third embodiment is used, the connection method of the first embodiment (FIG. 4) or the connection method of the second embodiment (FIG. 8) is used. can do. In this case, the power source selection switch Sv may be switched to electrically connect the AC power source device 10 and the partial discharge detection device 14. Thus, the discharge detection system of FIG. 9 can detect not only between turns but also partial discharges between different phases and between grounds and their occurrence positions.

DESCRIPTION OF SYMBOLS 10 ... AC power supply device, 12 ... Stator installation part, 14 ... Partial discharge detection device, 16 ... Voltage detection device, 20 ... Impulse generator, 30 ... Stator, 32 ... Stator coil, 34 ... Stator core, 35 DESCRIPTION OF SYMBOLS ... Penetration part, 36 ... Connection part, 51 ... 1st oscilloscope, 52 ... 2nd oscilloscope, 61 ... 1st axial direction antenna apparatus, 62 ... 2nd axial direction antenna apparatus, 70 ... Circumferential direction antenna apparatus group 71 ... 1st circumferential antenna device, 72 ... 2nd circumferential antenna device, 73 ... 3rd circumferential antenna device, 74 ... 4th circumferential antenna device, 75 ... 5th circumferential antenna device 76 ... Sixth circumferential antenna device, 77 ... Seventh circumferential antenna device, 78 ... Eighth circumferential antenna device

Claims (11)

A stator coil;
A stator core in which a plurality of slots into which the stator coils are inserted are formed in the circumferential direction;
An insulating portion for insulating at least between the inner surface of the slot and the conductor surface of the stator coil;
In a discharge detection method for detecting a discharge generated in the insulating portion of the stator for a rotating electrical machine having
A coil connection step for connecting the insulation coil so that a predetermined voltage is applied to the insulation portion;
An application step of applying a predetermined voltage to the stator coil after the coil connection step;
A first discharge detecting step of detecting a discharge generated in the insulating portion with a pair of axial antennas disposed on both sides in the axial direction of the stator for a rotating electric machine during the application step;
An axial position specifying step for specifying an axial position of the discharge based on the discharge detected in the first discharge detecting step;
During the application process, a discharge generated in the insulating portion by a plurality of circumferential antenna devices arranged in the circumferential direction at a predetermined axial position of the rotating electrical machine stator and spaced apart from each other in the circumferential direction. A second discharge detecting step for simultaneously detecting the two in parallel with each other ;
Based on the discharge detected in the second discharge detection step, a circumferential position specifying step for specifying a circumferential position of the discharge;
A discharge detection method comprising:   2. The discharge according to claim 1, wherein the circumferential discharge specifying step includes a step of specifying a circumferential position of the discharge generation at an axial position of the discharge generation specified in the axial discharge step. Detection method.   3. The discharge detection method according to claim 1, wherein the stator coil includes at least three phases and an inter-phase insulating portion in which different phases are insulated from each other. 4. The connecting step includes a step of connecting so that a predetermined voltage is applied between two phases of the three phases,
The applying step includes a step of applying a predetermined voltage between the two phases connected in the connecting step;
The discharge detection method according to claim 3. The connection step includes a step of connecting between any one of the three phases and the ground portion,
The application step includes a step of applying a predetermined voltage between the phase and the ground portion connected in the connection step;
The discharge detection method according to claim 3. The stator coil has a turn-to-turn insulation portion in which the turns of the stator coil for each phase are insulated;
The connecting step includes a step of connecting so that an impulse voltage of a predetermined intensity can be applied between any one of the three phases and the ground part,
The applying step includes a step of applying an impulse voltage between the phase connected in the connecting step and the ground portion;
The discharge detection method according to claim 3. A stator coil;
A stator core in which a plurality of slots into which the stator coils are inserted are formed in the circumferential direction;
An insulating portion for insulating at least between the inner surface of the slot and the conductor surface of the stator coil;
In a discharge detection method for detecting a discharge generated in the insulating portion of the stator for a rotating electrical machine having
A coil connection step for connecting the insulation coil so that a predetermined voltage is applied to the insulation portion;
An application step of applying a predetermined voltage to the stator coil after the coil connection step;
Wherein the duration of the application process, the circumferential antenna unit group composed if either a plurality of antenna apparatus are arranged circumferentially spaced circumferentially apart from one another, a plurality arranged at predetermined axial intervals, said plurality In the antenna device, a discharge detection step of simultaneously detecting the discharge generated in the insulating portion in parallel with each other ,
Based on the discharge detected in the discharge detection step, an axial position specifying step for specifying an axial position and a circumferential position of the discharge, and
A discharge detection method comprising: A stator coil;
A stator core in which a plurality of slots into which the stator coils are inserted are formed in the circumferential direction;
At least an insulating portion that insulates between the inner surface of the slot and the conductor surface of the stator coil;
In a discharge detection system for measuring a discharge generated in the insulating portion of the stator for a rotating electrical machine having
A pair of axial antenna devices arranged on both sides in the axial direction of the rotating electric machine stator and capable of sensing electromagnetic waves radiated by discharge;
A plurality of circumferential antenna devices that are arranged at circumferential intervals at circumferential positions at predetermined axial positions of the rotating electric machine stator, and that can simultaneously detect electromagnetic waves radiated by discharge in parallel with each other ;
When electrically connected to each of the pair of axial antenna devices and each of the circumferential antenna devices, and when at least one of the pair of axial antenna devices and each of the circumferential antenna devices senses a discharge, A signal reader configured to be able to input an electrical signal indicating the effect,
A discharge detection system comprising: The stator coil comprises at least three phases, and the insulating part is insulated between different phases;
The discharge detection system according to claim 8. The insulating part is insulated between the turns of the stator coil of each phase,
Wired so that an impulse voltage of a predetermined intensity can be applied to any one of the three phases,
10. The discharge detection system according to claim 8 or 9, wherein: A stator coil;
A stator core in which a plurality of slots into which the stator coils are inserted are formed in the circumferential direction;
At least an insulating portion that insulates between the inner surface of the slot and the conductor surface of the stator coil;
In a discharge detection system for measuring a discharge generated in the insulating portion of the stator for a rotating electrical machine having
A circumferential antenna group consisting of a plurality of antenna devices, each of which is capable of sensing an electromagnetic wave radiated by a discharge and arranged in the circumferential direction with a circumferential spacing therebetween and capable of sensing in parallel with each other, has a predetermined axial spacing. A plurality of antenna devices arranged in an array;
A signal reader that is electrically connected to each of the antenna devices and configured to be able to input an electrical signal indicating that when at least one of the antenna devices senses a discharge;
A discharge detection system comprising:

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