Rotor detection device and rotor detection method

Abstract

A rotor detection device (1) according to the present disclosure comprises: a base frame (3); a probe (2) that is connected to the base frame (3) and that is for detecting the state of a wedge (912) which is disposed on the outer circumferential surface (910fo) side of a rotor (910) by contacting the wedge (912); a circumferential position calculation unit (71) that calculates the circumferential position of the rotor (910) with respect to the base frame (3); and a control unit (7) that controls a detection operation by the probe (2) on the basis of the circumferential position calculated by the circumferential position calculation unit (71).

Description

Rotor inspection device and rotor inspection method

[0008] ,

[0007] , ,

[0001] The present disclosure relates to a rotor inspection device and a rotor inspection method.

[0002] In the rotor that constitutes a rotating electrical machine, in order to hold the coil housed in the slots of the iron core, a wedge is provided that is fitted from the outer peripheral side of the slot. However, if a crack occurs in the wedge due to the influence of the centrifugal force generated by the rotation of the rotor, it may cause a failure of the rotating electrical machine. Although the crack can be inspected by pulling out the rotor from the stator, there is a concern that the downtime will be prolonged and damage will be caused to the stator and the rotor during the pulling out or reinsertion.

[0003] Therefore, a inspection device has been proposed that adheres to the teeth of the stator by magnetic adsorption force and can travel in the axial direction within the gap between the stator and the rotor (see, for example, Patent Document 1).

[0004] International Publication No. WO2022 / 249290 (paragraphs 0014 to 0020, FIGS. 2, FIGS. 3, FIGS. 6)

[0005] However, in order to inspect all the wedges arranged in the circumferential direction, every time the axial movement ends, it is necessary to reinstall the inspection device at different positions in the circumferential direction of the stator, which is a time-consuming problem.

[0006] The present disclosure solves the above problems and aims to inspect a plurality of wedges arranged on the rotor without reinstalling the device.

[0007] The rotor inspection device of the present disclosure includes a base frame that is positioned and installed with respect to the inner peripheral surface of the stator of a rotating electrical machine, a probe that is connected to the base frame and contacts a member arranged on the outer peripheral surface side of the rotor that faces the inner peripheral surface of the stator with a gap to inspect the state of the member, a circumferential position calculation unit detection unit that calculates the circumferential position of the rotor with respect to the base frame, and a control unit that controls the inspection operation by the probe based on the circumferential position calculated by the circumferential calculation unit.

[0008] The rotor inspection method of the present disclosure is characterized by comprising the steps of: inserting an inspection device having a probe into the gap between the stator and the rotor of a rotating electric machine and positioning it with respect to the inner circumferential surface of the stator; moving and fixing the inspection device to a position along the axial direction on the inner circumferential surface that is opposite to an area on the outer circumferential surface of the rotor in which a plurality of inspection targets are arranged along the circumferential direction; and rotating the rotor while the axial position of the inspection device is fixed, and bringing the probe into contact with each of the plurality of inspection targets to inspect each of the plurality of inspection targets.

[0009] According to the rotor inspection device or rotor inspection method of this disclosure, the wedges arranged in the circumferential direction can be sequentially inspected by rotating the rotor, so that multiple wedges arranged on the rotor can be inspected without having to reattach the device.

[0010] This is a front view illustrating the configuration of the rotor inspection device according to Embodiment 1. This is a functional block diagram illustrating the configuration of the control unit of the rotor inspection device according to Embodiment 1. Figures 3A and 3B are a cross-sectional view perpendicular to the axis and a cross-sectional view including the axis, illustrating the configuration of the rotating electric machine that is the target of inspection by the rotor inspection device or rotor inspection method according to Embodiment 1. Figures 4A and 4B are a cross-sectional view perpendicular to the axis of the outer peripheral surface portion of the rotor and a further enlarged cross-sectional view of a part thereof, illustrating the configuration of the rotating electric machine that is the target of inspection by the rotor inspection device or rotor inspection method according to Embodiment 1. This is a flowchart illustrating the operation of the rotor inspection device or rotor inspection method according to Embodiment 1. This is a cross-sectional view perpendicular to the axis showing the rotor inspection device according to Embodiment 1 installed in the gap between the rotor and the stator. This is a graph showing the change in distance measured by a laser displacement meter used to determine the circumferential position of the rotor in the rotor inspection device or rotor inspection method according to Embodiment 1. This is a block diagram illustrating the hardware configuration of the part of the rotor inspection device according to Embodiment 1 that performs calculation processing.

[0011] Embodiment 1. Figures 1 to 7 illustrate the configuration and operation of the rotor inspection device or rotor inspection method according to Embodiment 1. Figure 1 is a front view taken from a distant position in the axial direction to illustrate the configuration of the rotor inspection device. Figure 2 is a functional block diagram to illustrate the configuration of the control unit of the rotor inspection device. Figure 3A is a cross-sectional view perpendicular to the shaft of the rotating electric machine to be inspected. Figure 3B is a cross-sectional view including the shaft of the rotating electric machine. Figure 4A is a cross-sectional view perpendicular to the shaft of the outer circumferential surface portion of the rotor of the rotating electric machine. Figure 4B is a cross-sectional view further enlarged from the region R portion of Figure 4A.

[0012] Figure 5 is a flowchart illustrating the operation of the rotor inspection device or the rotor inspection method, and Figure 6 is a cross-sectional view perpendicular to the axis of the area around the gap where the rotor inspection device is installed and positioned and fixed relative to the stator. Figure 7 is a graph showing the change over time in the distance to the outer surface of the rotor, as measured by a laser displacement meter used to determine the circumferential position when the rotor is rotated.

[0013] Before describing the rotor inspection device and rotor inspection method according to Embodiment 1, the rotor to be inspected and the rotating electric machine equipped with the rotor will be described. As shown in Figures 3A and 3B, the rotating electric machine 900 consists of an annular stator 920 and a rotor 910 that is concentrically arranged radially inward from the stator 920 and rotatably supported around an axis 913. The outer circumferential surface 910fo of the rotor 910 faces the inner circumferential surface 920fi of the stator 920 with a gap 900g between them. The outer circumferential surface side of the stator 920 is fixed by a cylindrical housing 930.

[0014] On the outer circumferential surface 910fo of the iron core 911 of the rotor 910, as shown in Figures 4A and 4B, a plurality of teeth 911t protruding outward are formed so as to accommodate a plurality of slots 910s spaced along the circumferential direction Dc. These slots accommodate coils (not shown). Wedges 912 are fitted to close the openings on the outer circumferential side of the slots 910s in order to hold the coils within the slots 910s. Since the wedges 912 are basically fitted to each slot 910s, they are arranged regularly along the circumferential direction Dc. This regular arrangement along the circumferential direction Dc is also formed at different positions in the axial direction Da.

[0015] In other words, the number of wedges 912 to be inspected is the number of slots 910s along the circumferential direction Dc multiplied by the number of different positions along the axial direction Da. For example, if a rotating electric machine 900 has 20 to 40 slots 910s along the circumferential direction Dc and wedges 912 fitted at 3 to 10 different positions along the axial direction Da, then 60 to 400 wedges 912 need to be inspected.

[0016] In particular, in the circumferential direction Dc, there are more than 20 wedges 912, so the technology described in Patent Document 1 requires the inspection device to be reattached more than 20 times, which is time-consuming and laborious. Furthermore, if the inspection device is attached to the inner circumferential surface of the stator that faces downwards, there is a possibility that it may fall onto the rotor 910 and damage it if there is a malfunction in magnetic attraction.

[0017] Therefore, the rotor inspection device 1 according to Embodiment 1 is configured on the premise that it will be inserted into the gap 900g in the upward-facing region of the inner circumferential surface 920fi of the stator 920, rest on the inner circumferential surface 920fi by its own weight, and rotate the rotor 910. As shown in Figure 1, it comprises a base frame 3 that is positioned and placed on the inner circumferential surface 920fi of the stator 920, a probe 2 for inspecting the wedge 912 of the rotor 910, and a link 5 that extends the probe 2 toward the wedge 912 during inspection. The link 5 is configured not only for the extension operation during inspection, but also to reduce the radial thickness by housing the probe 2 inside the base frame 3 when inserting the device into the gap 900g.

[0018] The base frame 3 is provided with a pair of guides 3g on its surface 1fs facing the stator 920 to prevent misalignment in the circumferential direction Dc relative to the stator 920. Furthermore, a traveling body 4, equipped with a pair of wheels 4d for moving the device along the axial direction Da, is positioned on each side of the base frame 3 in the circumferential direction Dc. While the example shows the guides 3g positioned on the base frame 3, this is not the only option; for example, they may be positioned on the traveling body 4. The spacing between the pair of guides 3g and the pair of wheels 4d in the circumferential direction Dc can be freely adjusted according to the specifications of the rotating electric machine 900 being inspected.

[0019] Furthermore, the base frame 3 is equipped with a laser displacement meter 6 for measuring the distance to the outer circumferential surface 910fo of the rotor 910. The rotor inspection device 1 also includes a control unit 7 for coordinating the operation of various parts within the device, as well as with external components or the rotor 910.

[0020] As shown in Figure 2, the control unit 7 includes an inspection control unit 71 that controls the inspection operation, and a probe control unit 75 that controls the operation of the probe 2 and link 5 in accordance with the commands of the inspection control unit 71. It also includes a circumferential position calculation unit 73 that calculates the circumferential position of the rotor 910 based on the output (changes) from the laser displacement meter 6, and an axial control unit 74 that controls the traveling body 4 to control the axial position Da. Furthermore, it includes an interface 72 (indicated as I / F in the figure) that performs input / output operations such as communication with the rotating electric machine 900, display to the operator performing the inspection, and receiving input from the operator.

[0021] Furthermore, it includes a rotating electric machine specification database 77 (indicated as DB in the diagram) that stores specifications for each rotating electric machine 900, such as the shape of the outer circumferential surface 910fo including the position of the wedge 912 and the shape data of the inner circumferential surface 920fi of the stator 920, linked to the model number of the rotating electric machine 900. In addition, it includes a circumferential control unit 76 that controls the rotation (circumferential position) of the rotor 910 during inspection based on the specifications of the rotating electric machine 900.

[0022] Furthermore, the rotor 910 may be equipped with a camera (not shown) to acquire an image of its outer surface 910fo, which can then be transmitted to the operator's display device via the interface 72, allowing the image to be displayed in real time.

[0023] Based on the above configuration, the operation of the rotor inspection device 1 and the rotor inspection method of this disclosure will be explained with reference to the flowchart in Figure 5. First, when information such as the model number of the rotating electric machine 900 to be inspected is input via the interface 72, the inspection control unit 71 reads the specifications of the corresponding rotating electric machine 900 from the rotating electric machine specification database 77 (step S100). Then, based on the read specifications of the stator 920, such as the spacing of the teeth 921t (Figure 6), the spacing between the wheels 4d and the guides 3g is adjusted.

[0024] Next, as shown in Figure 6, the rotor inspection device 1 is positioned and installed within the gap 900g between the rotor 910 and the stator 920, relative to the upward-facing inner surface 920fi of the stator 920, such that the guide 3g is sandwiched between the sides of the two teeth 921t protruding from the iron core 921 (step S110). When inserting the rotor inspection device 1 into the gap 900g, the link 5 is operated to house the probe 2 on the base frame 3 side, allowing it to pass through the section where the gap narrows near the entrance.

[0025] At this time, the rotor inspection device 1 presses against the inner circumferential surface 920fi due to its own weight, so the guide 3g comes into contact with the side surface of the teeth 921t (the irregularities along the inner circumferential surface 920fi that extend along the axial direction Da), thereby restricting movement along the circumferential direction Dc. On the other hand, the guide 3g is configured to slide along the axial direction Da relative to the side surface of the teeth 921t, so as not to hinder the movement of the device along the axial direction Da.

[0026] In this state, based on the data of the position of the wedge 912 in the axial direction Da, the wheel 4d is driven to move the device to an axial position where it can be inspected (step S200). Subsequently, the circumferential control unit 76 issues a command via the interface 72 to the rotor 910 or a turning device (not shown) that controls the rotation of the rotor 910, causing the rotor 910 to start rotating at a rotational speed according to the specifications (step S300).

[0027] As the rotor 910 rotates, the distance from the laser displacement meter 6 to the rotor 910 changes over time as shown in Figure 7, due to changes in the teeth 911t, the wedge 912, and the groove 910c between the teeth 911t and the wedge 912 (Figure 4B), as well as changes in the laser irradiation target. The circumferential position calculation unit 73 then detects a peak Pk where the distance rises sharply, and from the distance change data, it can determine the position of the wedge 912 relative to the device (more precisely, the probe 2). As data for the distance change, for example, the spacing between peaks Pk, or the shape of the peak Pk itself, such as upward sloping or downward sloping, allows this section to be distinguished as "wedge i" or "wedge i+1".

[0028] Then, based on the data from the circumferential position calculation unit 73, when the inspection control unit 71 determines that it has entered the inspection position of the first wedge 912 (wedge i) at a certain axial position ("Yes" in step S410), it extends the link 5 and presses the probe 2 against the wedge i to perform a probe inspection (step S420). During the probe inspection, the probe is scanned along the circumferential direction Dc with respect to the wedge 912, and it is determined whether the operation has been completed for each wedge 912 (step S430). The probe inspection is then performed until the scanning of one wedge is completed ("Yes" in step S430).

[0029] During scanning, the circumferential position of the probe 2 may remain fixed, and scanning may be performed by movement relative to the wedge 912 due to the rotation of the rotor 910, but this is not the only option. For example, as disclosed in Patent Document 1, a mechanism may be provided to move the probe 2 along the circumferential direction Dc relative to the base frame 3, and during this time, the rotation of the rotor 910 may be stopped, and scanning may be performed by moving the probe 2. Furthermore, the rotation of the rotor 910 may be set faster than the rotational speed required for scanning, and the probe 2 may be moved faster than that rotation to optimize the relative speed with respect to the wedge 912. This reduces the time required for movement between the wedges 912 and the intermediate portion between them, further reducing inspection time.

[0030] Once scanning one wedge is complete ("Yes" in step S430), the inspection control unit 71 determines whether the inspection of one full rotation of wedges 912 at that axial position has been completed (step S440). For example, if the inspection of one full rotation has not been completed, such as when scanning fewer than 32 wedges 912 in one rotation ("No" in step S440), the process proceeds to step S400 to perform a probe inspection of the next wedge 912.

[0031] If the inspection for one full rotation is completed (Yes in step S440), the inspection control unit 71 determines whether the movement in the axial direction Da relative to the arrangement distribution of the wedges 912 is the last (step S500). If the movement in the axial direction Da is not the last (No in step S500), the process proceeds to step S200, where the inspection control unit 71, via the axial control unit 74, controls the traveling body 4 to move the device to the next axial position and repeats the above-described operation.

[0032] The inspection is completed when the movement in the axial direction Da is finished ("Yes" in step S500). At this point, the wedge 912 may be allowed to move out of the gap 900g on its own, or it may be moved to a position that is easy for the operator to remove. This makes it possible to inspect all wedges 912 without having to change the mounting of the device midway through the inspection. Also, during the inspection, the rotor inspection device 1 maintains a state in which it is pressing against the inner circumferential surface 920fi by its own weight, so it will not fall and will not damage the rotating electric machine 900.

[0033] Furthermore, even when the rotation axis is oriented vertically, if the wedge 912 is configured to be magnetically attracted to the stator 920, as in Patent Document 1, all wedges 912 can be inspected without having to change the device's mounting midway through the process. In that case, if the device is secured with a rope or the like to prevent it from falling, even if the magnetic attraction is lost, the device will not directly hit the rotor 910 or stator 920, and the rotating electric machine 900 will not be damaged.

[0034] The control unit 7 can be configured, for example, as shown in Figure 8, by a single hardware unit 700 comprising a processor 701 and a storage device 702. The storage device 702, although not shown, comprises a volatile storage device such as random access memory and a non-volatile auxiliary storage device such as flash memory. Alternatively, a hard disk may be provided as an auxiliary storage device instead of flash memory. The processor 701 executes the program input from the storage device 702. In this case, the program is input from the auxiliary storage device to the processor 701 via the volatile storage device. The processor 701 may also output data such as calculation results to the volatile storage device of the storage device 702, or it may save the data to the auxiliary storage device via the volatile storage device.

[0035] While this disclosure describes exemplary embodiments, the various features, aspects, and functions described in the embodiments are not limited to the application of any particular embodiment, but can be applied individually or in various combinations to the embodiments. Accordingly, countless variations not illustrated are conceivable within the scope of the art disclosed in this specification. These include, for example, modifications, additions, or omissions of at least one component.

[0036] This disclosure shows an example in which the rotation of the rotor 910 is controlled by the rotor inspection device 1, but it is not limited to this. For example, in step S410, if it is determined that the inspection position has been entered, a signal is output that the operator can recognize, and the rotation of the rotor 910 may be controlled by the operator. Furthermore, the spacing of the guide 3g, wheels 4d, etc. may also be manually adjusted by the operator in accordance with the specifications of the rotating electric machine 900.

[0037] Furthermore, the sensor used to detect the circumferential position is not limited to the laser displacement meter 6; a camera may be used instead. In that case, the camera and image analysis device can be used in combination to determine whether or not it is an inspection position. Also, regarding movement along the axial direction Da, the device may be moved by pushing or pulling it from an external source along the axial direction Da, rather than being self-propelled by the control of the axial control unit 74.

[0038] Furthermore, while the rotor inspection device 1 and rotor inspection method of this disclosure show an example of inspecting the condition of the wedge 912, the invention is not limited to this. If the components are arranged along the circumferential direction Dc, such as teeth 911t and coils not blocked by the wedge 912, it is possible to obtain the effect of being able to inspect all components without having to change the device midway through the process. In addition, if the objects to be inspected are arranged irregularly along the circumferential direction Dc, the presence or absence of the inspection range may be determined based on the surface shape, image, or arrangement pattern specification data of the objects to be inspected.

[0039] As described above, the rotor inspection device 1 of this disclosure includes a base frame 3 positioned and installed relative to the inner circumferential surface 920fi of the stator 920 of the rotating electric machine 900; a probe 2 connected to the base frame 3 for inspecting the condition of a member (wedge 912) positioned on the outer circumferential surface 910fo side of the rotor 910, which faces the inner circumferential surface 920fi of the stator 920 with a gap 900g between them; a circumferential position calculation unit 73 (laser displacement meter 6) for calculating the circumferential position of the rotor 910 relative to the base frame 3; and a control unit 7 for controlling the inspection operation by the probe 2 based on the circumferential position calculated by the circumferential position calculation unit 73. This makes it possible to efficiently inspect a plurality of wedges 912 arranged along the circumferential direction Dc without having to reattach the rotor inspection device 1 to the inner circumferential surface 920fi of the stator 920.

[0040] Furthermore, if the control unit 7 has a function (interface 72) that notifies the outside when the member to be inspected (wedge 912) reaches the inspection position due to the rotation of the rotor 910, the rotation of the rotor 910 can be controlled efficiently.

[0041] Further, if a circumferential control unit 76 for controlling the rotational drive of the rotor 910 is provided in the control unit 7, the rotational drive of the rotor 910 can be automatically controlled.

[0042] If a guide 3g is provided which enters the irregularities formed along the circumferential direction Dc of the inner circumferential surface 920fi of the stator 920 and prevents the circumferential displacement of the base frame 3 with respect to the stator 920 in the circumferential direction Dc, the inspection of the wedge 912 can be surely executed without causing circumferential displacement in the circumferential direction Dc during the inspection operation or the axial movement operation.

[0043] If a traveling mechanism (traveling body 4) for moving the base frame 3 in the axial direction Da with respect to the inner circumferential surface 920fi of the stator 920 is provided, smooth axial movement becomes possible.

[0044] As described above, according to the rotor inspection method of the present disclosure, a step (step S110) of inserting an inspection device (rotor inspection device 1) having a probe 2 into the gap 900g between the stator 920 and the rotor 910 of the rotating electrical machine 900 and positioning and arranging it with respect to the inner circumferential surface 920fi of the stator 920, among the positions along the axial direction Da on the inner circumferential surface 920fi, at a position facing the region where a plurality of inspection targets (wedges 912) are arranged along the circumferential direction Dc on the outer circumferential surface 910fo of the rotor 910, moving and fixing the inspection device (rotor inspection device 1), and a step of rotating the rotor 910 while the position of the inspection device (rotor inspection device 1) in the axial direction Da is fixed, and bringing the probe 2 into contact with each of the plurality of inspection targets (wedges 912) to inspect each of the plurality of inspection targets (wedges 912) (steps S400 to S440) are configured to be included. Thereby, the plurality of wedges 912 arranged along the circumferential direction Dc can be efficiently inspected without re-mounting the rotor inspection device 1 with respect to the inner circumferential surface 920fi of the stator 920.

[0045] 1: Rotor inspection device (inspection device), 2: Probe, 3: Base frame, 3g: Guide, 4: Traveling body, 5: Link, 6: Laser displacement meter, 7: Control unit, 71: Inspection control unit, 72: Interface, 73: Circumferential position calculation unit, 74: Axial control unit, 75: Probe control unit, 76: Circumferential control unit, 77: Rotating electric machine specification database, 900: Rotating electric machine, 900g: Gap, 910: Rotor, 910fo: Outer surface, 911: Iron core, 911t: Teeth, 912: Wedge (member), 920: Stator, 920fi: Inner surface, 921: Iron core, 921t: Teeth, Da: Axial direction, Dc: Circumferential direction, Pk: Peak.

Claims

1. A rotor inspection device comprising: a base frame positioned and installed relative to the inner circumferential surface of a stator of a rotating electric machine; a probe connected to the base frame and in contact with a member positioned on the outer circumferential surface side of the rotor, which is opposed to the inner circumferential surface of the stator with a gap between them, for inspecting the condition of the member; a circumferential position calculation unit for calculating the circumferential position of the rotor relative to the base frame; and a control unit for controlling the inspection operation by the probe based on the circumferential position calculated by the circumferential position calculation unit.

2. The rotor inspection device according to claim 1, characterized in that the control unit has a function to notify the outside when the member to be inspected reaches the inspection position due to the rotation of the rotor.

3. The rotor inspection device according to claim 1 or 2, characterized in that the control unit is provided with a circumferential control unit that controls the rotational drive of the rotor.

4. The rotor inspection device according to any one of claims 1 to 3, characterized in that it is provided with a guide that enters into irregularities formed along the circumferential direction on the inner surface of the stator and prevents circumferential displacement of the base frame relative to the stator.

5. The rotor inspection device according to claim 4, further comprising a travel mechanism for moving the base frame axially relative to the inner circumferential surface of the stator.

6. A rotor inspection method characterized by comprising the steps of: inserting an inspection device having a probe into the gap between the stator and rotor of a rotating electric machine and positioning it relative to the inner circumferential surface of the stator; moving and fixing the inspection device to a position along the axial direction on the inner circumferential surface that is opposite to an area on the outer circumferential surface of the rotor in which a plurality of inspection targets are arranged along the circumferential direction; and rotating the rotor while the axial position of the inspection device is fixed, and bringing the probe into contact with each of the plurality of inspection targets to inspect each of the plurality of inspection targets.

Images