JP2019203861A - System and method for detecting anomalies of main shaft bearing of wind power generator - Google Patents

Abstract

To provide a system and a method for detecting anomalies of a wind power generator main shaft bearing, which enhance accuracy in detection of damage to a main shaft bearing of a wind power generator.SOLUTION: A wind power generator main shaft bearing anomaly detection system is provided, comprising: a detection unit for detecting vibration of a main shaft bearing of a wind power generator; and a diagnostic unit configured to set a frequency band for assessing vibration information detected by the detection unit, and perform main shaft bearing anomaly determination processing using the vibration information limited to the frequency band set thereby.SELECTED DRAWING: Figure 10

Description

  The present invention relates to an abnormality detection system and an abnormality detection method for a main shaft bearing of a wind power generator.

  In recent years, wind power generation is rapidly spreading as a clean energy source that does not generate carbon dioxide that causes global warming.

  In a wind power generator, a main shaft bearing and a generator bearing that rotatably support a main shaft to which the rotor is attached are based on the rotational motion of the rotor caused by wind force as a power source of the generator. In order to stably supply power by a wind power generator, it is necessary to detect such abnormalities in various bearings at an early stage. For example, bearing anomalies can be detected by performing vibration analysis of the bearing using Fast Fourier Transform (FFT) processing and detecting the peak component of the frequency vibration that is characteristic of the damaged position of the bearing. It is said that. For example, as a method for diagnosing a bearing abnormality using FFT processing, a technique for diagnosing a rolling bearing abnormality based on the effective value of the vibration waveform and the effective value of the AC component of the envelope waveform is disclosed (for example, Patent Document 1). ).

JP 2011-154020 A

  When detecting damage to the main shaft bearing of a wind power generator, disturbance such as the meshing frequency of the gear of the gearbox may be disturbed and vibration analysis may be hindered, and the abnormality may not be detected accurately. Further, the load applied to the main shaft bearing is large, and the shock vibration at the time of damage can excite the structural system of the wind power generator. In the above prior art, the low-frequency component is cut off using a high-pass filter, and the result of frequency analysis is used in combination to improve the reliability of the abnormality diagnosis result. For example, the main axis of a wind power generator When the vibration frequency due to the damage of the bearing and the vibration frequency due to the plurality of disturbance elements are close to each other, there is a possibility that the detection accuracy of the damage to the main shaft bearing of the wind power generator is lowered.

  The present invention has been made in view of the above problems, and provides an abnormality detection system and an abnormality detection method for a main shaft bearing of a wind power generator that can improve the accuracy of detecting damage to the main shaft bearing of the wind power generator. The purpose is.

  In order to achieve the above object, an abnormality detection system for a main shaft bearing of a wind power generator according to an aspect of the present invention includes a detection device that detects vibration of the main shaft bearing of the wind power generator, and vibration detected by the detection device. A diagnostic device that sets a frequency band for determining the information and performs an abnormality determination process of the spindle bearing based on vibration information limited to the set frequency band.

  Thereby, the frequency component of the vibration by disturbance elements other than the vibration frequency resulting from the damage of the main shaft bearing of a wind power generator can be suppressed, and the detection accuracy of the damage of the main shaft bearing of a wind power generator can be improved.

  As a desirable mode of an abnormality detection system for a main shaft bearing of a wind power generator, the detection device detects a rotation speed of the wind power generator, and the diagnosis device performs a frequency of performing the abnormality determination process according to the rotation speed. It is preferable to set a band.

  Thereby, the frequency band at the time of performing the vibration analysis process of the main shaft bearing of the wind power generator can be appropriately set regardless of the rotational speed of the wind power generator.

  As a desirable mode of an abnormality detection system for a main shaft bearing of a wind power generator, the diagnostic device includes a first frequency band having a frequency band that is higher than the first frequency and higher than the first frequency and less than the second frequency as a pass band. And setting one or both of the second frequency bands not including the first frequency band and having a frequency band higher than the third frequency as a pass band as a frequency band for performing the abnormality determination process. Is preferred.

  Thereby, the frequency component of the vibration contained in the frequency band except one or both of the first frequency band and the second frequency band can be suppressed.

  As a desirable mode of an abnormality detection system for a main shaft bearing of a wind power generator, the wind power generator has a plurality of gear mechanisms configured by meshing gears provided on two rotating shafts, and the plurality of gear mechanisms. Includes a first gear mechanism and a second gear mechanism, wherein the first frequency is higher than a primary component of a frequency of vibration generated in the first gear mechanism, and the second frequency is The first frequency component of the vibration generated in the second gear mechanism is preferably lower.

  Thereby, the primary component of the frequency of vibration generated in the first gear mechanism and the primary component of the frequency of vibration generated in the second gear mechanism are suppressed.

  As a desirable mode of an abnormality detection system for a main shaft bearing of a wind power generator, the wind power generator has a plurality of gear mechanisms configured by meshing gears provided on two rotating shafts, and the plurality of gear mechanisms. Includes a first gear mechanism and a second gear mechanism, and the first frequency is based on an m-order component of a frequency of vibration generated in the first gear mechanism (m is a natural number of 1 or more). The second frequency is preferably lower than the n-order component (n is a natural number of 1 or more) of the frequency of vibration generated in the second gear mechanism.

  Thereby, the frequency up to the m-th order component of the vibration frequency generated in the first gear mechanism and the n-th order component or more of the vibration frequency generated in the second gear mechanism are suppressed.

  As a desirable aspect of the anomaly detection system for the main shaft bearing of the wind power generator, it is preferable that the frequency is higher than the frequency of vibration excited by impact vibration propagating from the blade of the wind power generator.

  Thereby, the frequency component of the vibration excited by the impact vibration propagating from the blade of the wind power generator is suppressed.

  As a desirable mode of an abnormality detection system for a main shaft bearing of a wind power generator, the diagnostic device may perform primary determination processing in the abnormality determination processing based on an effective value or partial overall value of vibration limited to the frequency band. preferable.

  Thereby, before performing a vibration analysis, it can be determined that there is no abnormality in the main shaft bearing.

  As a desirable mode of an abnormality detection system for a main shaft bearing of a wind power generator, when an abnormality is detected in the primary determination process, the diagnostic device performs an analysis process of vibration limited to the frequency band, and the analysis result Based on the above, it is preferable to perform the secondary determination process in the abnormality determination process.

  Thereby, damage to the main shaft bearing can be appropriately determined.

  The abnormality detection method for a main shaft bearing of a wind power generator according to an aspect of the present invention is limited to the step of setting a frequency band for determining vibration information of the main shaft bearing of the wind power generator and the set frequency band. Based on the effective value or partial overall value of vibration, performing a primary determination process of the main shaft bearing, and when an abnormality is detected in the primary determination process, performing an analysis process of vibration limited to the frequency band, The method includes a step of performing a secondary determination process on the spindle bearing based on the result of the analysis process, and a step of outputting the result of the primary determination process or the secondary determination process.

  Thereby, the influence by the vibration frequency by disturbance elements other than the vibration frequency resulting from the damage of the main shaft bearing of a wind power generator can be suppressed, and the detection accuracy of the damage of the main shaft bearing of a wind power generator can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, the abnormality detection system and abnormality detection method of the main shaft bearing of a wind power generator which can raise the detection accuracy of the main shaft bearing of a wind power generator can be provided.

FIG. 1 is a schematic configuration diagram illustrating an example of an overall configuration of a wind power generation system to which an abnormality detection system for a main shaft bearing of a wind power generator according to an embodiment is applied. FIG. 2 is a schematic structural diagram of the wind power generator. FIG. 3 is a schematic view showing an example of the structure of the speed increaser. FIG. 4 is a diagram illustrating an example of a diagnosis device in the abnormality diagnosis system for the main shaft bearing of the wind power generator according to the embodiment. FIG. 5 is a schematic diagram illustrating an example of the abnormality determination process. FIG. 6 is an image diagram showing the relationship between the rotational speed of the wind power generator and the frequency band in the abnormality determination process. FIG. 7A is a diagram illustrating an effective value calculation process result of a vibration analysis process result depending on the presence / absence of a band limitation process. FIG. 7B is an enlarged view of (b) and (c) of FIG. 7A in the effective value direction. FIG. 8A is a diagram illustrating an effective value calculation process result of a vibration analysis process result depending on whether or not a band limiting process is performed when the power generation amount of the wind power generator is relatively small. FIG. 8B is an enlarged view of (b) and (c) of FIG. 8A in the effective value direction. FIG. 9 is a diagram illustrating an example of a frequency analysis result in the abnormality detection system for the main shaft bearing of the wind power generator according to the embodiment. FIG. 10 is a flowchart illustrating an example of an abnormality determination processing procedure according to the embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, modes for carrying out the invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings. In addition, this indication is not limited by the following embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the constituent elements disclosed in the following embodiments can be appropriately combined.

  FIG. 1 is a schematic configuration diagram illustrating an example of an overall configuration of a wind power generation system to which an abnormality detection system for a main shaft bearing of a wind power generator according to an embodiment is applied.

  The wind power generation system 1 illustrated in FIG. 1 is provided in a collective wind power plant in which, for example, several tens of wind power generators 100 are installed on a vast site or on the ocean. The wind power generation system 1 includes a detection device 10 provided in each wind power generator 100 and a diagnosis device 20 provided in, for example, a collective wind power plant or an external management facility.

  FIG. 2 is a schematic structural diagram of the wind power generator. The wind power generator 100 includes a detection device 10, a rotor 30, a speed increaser 50, and a power generator 60. The detection device 10, the speed increaser 50, and the generator 60 are stored in the nacelle 70. The rotor 30, the main shaft 40, the speed increaser 50, the coupling 43, and the generator 60 are supported by a main shaft bearing 41 stored in a main shaft bearing housing 42 that is mounted on a base (frame) 90 supported by a tower 80. The The speed increaser 50 has a torque arm 53 mounted on a base (frame) 90 to prevent its own rotation, but the spindle bearing 41 receives its own weight.

  The rotor 30 includes a hub 31 and a plurality of blades 32 provided on the hub 31. The hub 31 is connected to the speed increaser 50 via the main shaft 40 and is rotatably supported by the main shaft bearing 41. The main shaft 40 transmits the rotational torque generated when the rotor 30 rotates due to the blade 32 receiving wind force to the gearbox 50.

  The speed increaser 50 is provided between the main shaft 40 and the generator 60. The speed increaser 50 increases the rotational speed of the main shaft 40 and outputs the increased rotational torque to the generator 60 via the output shaft 61.

  The generator 60 generates electric power using the rotational torque received from the speed increaser 50 via the output shaft 61. The generator 60 is constituted by, for example, an induction generator or a synchronous generator.

  The detection device 10 includes a data collection unit 11, a vibration sensor 12, a rotation speed sensor 13, and a power generation amount sensor 14.

  The vibration sensor 12 is, for example, an acceleration sensor, a speed sensor, a displacement sensor, or the like, and detects vibration generated in the wind power generator 100. FIG. 2 illustrates a configuration in which the vibration sensor 12 is only provided in the main shaft bearing housing 42. The present disclosure is not limited by the number of vibration sensors 12 or the attachment positions.

  The rotational speed sensor 13 is, for example, a rotational sensor such as a rotary encoder or a resolver, and detects the rotational speed (rotational speed) of the main shaft 40 or the output shaft 61, for example. In FIG. 2, the structure which provided only the rotational speed sensor 13 which detects the rotation speed (rotational speed) of the output shaft 61 is illustrated. The present disclosure is not limited by the number and types of rotation speed sensors 13, attachment positions, and the like.

  The power generation amount sensor 14 is, for example, a current sensor such as a Rogowski coil provided on any one of the three-phase output cables of the generator 60. This current sensor The amount of power generated by the wind power generator 100 is calculated from the current detected by. The power generation amount of the wind power generator 100 is acquired from a remote control monitoring system (SCADA: Supervision Control Data Acquisition) that monitors the wind power generation system 1 shown in FIG. 1 via a network such as an optical line, for example. Is possible. The present disclosure is not limited by the method for obtaining the power generation amount of the wind power generator 100. Further, the present disclosure is not limited by the mounting position of the power generation amount sensor 14.

  The data collection unit 11 collects the vibration detected by the vibration sensor 12, the rotational speed detected by the rotational speed sensor 13, and the power generation amount detected by the power generation amount sensor 14. The detection device 10 outputs the vibration, rotation speed, and power generation amount collected by the data collection unit 11 to the diagnosis device 20 via the network 200 (see FIG. 1). The network 200 may be, for example, an Internet line or a LAN (Local Area Network). Furthermore, each wind power generator 100 in the collective wind power plant is connected by a LAN, and a VPN (Virtual Private Network) is constructed with a LAN of an external management facility where the diagnostic device 20 is provided. Also good.

  FIG. 3 is a schematic view showing an example of the structure of the speed increaser. As shown in FIG. 3, the speed increaser 50 includes a housing 501 and a planetary gear device 502 and a secondary speed increasing device 503 housed in the housing 501.

  An input shaft 51 is rotatably supported on the housing 501 via an input shaft bearing 52. Further, on the inner side of the housing 501, a low speed shaft 505 disposed concentrically with the input shaft 51, and an intermediate shaft 506 and an output shaft 61 disposed in parallel with the low speed shaft 505 are respectively bearings ( It is supported rotatably via a reference number omitted).

  The planetary gear device 502 plays a role of increasing the rotation of the input shaft 51 and transmitting it to the low speed shaft 505.

  The planetary gear device 502 includes a sun gear 508, a ring gear 509, and a plurality of cylindrical planetary gears 510. The sun gear 508 is provided on the outer peripheral surface of one end portion (left end portion in FIG. 3) of the low speed shaft 505. The ring gear 509 is provided on the inner peripheral surface of the housing 501 and is arranged concentrically around the sun gear 508. The plurality of planetary gears 510 are arranged at equal intervals in the circumferential direction between the sun gear 508 and the ring gear 509. Then, the teeth provided on the outer peripheral surface of the planetary gear 510 are respectively meshed with the teeth provided on the outer peripheral surface of the sun gear 508 and the teeth provided on the inner peripheral surface of the ring gear 509 to constitute a gear mechanism. Yes. The planetary gears 510 are rotatably supported via a pair of cylindrical roller bearings 512 arranged in double rows around a cylindrical planetary shaft 511 parallel to the sun gear 508 and the ring gear 509, respectively. Has been. Further, the base end portion (left end portion in FIG. 3) of the planetary shaft 511 is supported and fixed to a carrier 513 provided integrally with one end portion (right end portion in FIG. 3) of the input shaft 51, respectively.

  The secondary speed increasing device 503 plays a role of further increasing the rotation of the low speed shaft 505 and transmitting it to the output shaft 61.

  The secondary speed increasing device 503 meshes a large-diameter input gear 524 that is externally fitted and fixed to the intermediate portion of the low-speed shaft 505 with a small-diameter first intermediate gear 525 provided on the outer peripheral surface of the intermediate portion of the intermediate shaft 506. The gear mechanism is configured. Further, the secondary speed increasing device 503 includes a large-diameter second intermediate gear 526 that is externally fitted and fixed to one end portion (left end portion in FIG. 3) of the intermediate shaft 506, and one end portion (left end portion in FIG. 3) of the output shaft 61. ) A gear mechanism is configured by meshing with an output gear 527 provided on the outer peripheral surface.

  The spindle bearing 41 shown in FIG. 2 is an abnormality detection target in the bearing abnormality detection system according to the present embodiment. In the example shown in FIG. 2, the vibration sensor 12 is provided in the vicinity of the main shaft bearing 41. The bearing abnormality detection system according to the present embodiment includes the vibration sensor 12, the rotation speed sensor 13, the detection device 10, and the diagnosis device 20, and detects damage to the main shaft bearing 41.

  FIG. 4 is a diagram illustrating an example of a diagnostic device in the abnormality detection system for the main shaft bearing of the wind power generator according to the embodiment. As shown in FIG. 4, the diagnostic device 20 is a general information processing terminal such as a PC, and includes a processing unit 21, a storage unit 22, a communication unit 23, an input unit 24, and a display unit 25. Are configured to be able to transmit and receive data via the bus 26.

  The processing unit 21 is a component that performs data transfer between the respective units via a predetermined memory and controls the entire diagnosis apparatus 20, and a program stored in a predetermined memory by a CPU (Central Processing Unit). It is realized by executing.

  The storage unit 22 is a configuration unit that stores data from the processing unit 21 and reads data stored by the processing unit 21, and is, for example, a non-volatile device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive). This is realized by a sexual memory device.

  The communication unit 23 is a component that communicates with the detection device 10 of each wind power generator 100, and is realized by, for example, a NIC (Network Interface Card) or the like.

  The input unit 24 is a component for an operator to input data and instructions, and is realized by, for example, a keyboard, a mouse, a touch panel, or the like.

  The display unit 25 is a component that displays data in response to an instruction from the processing unit 21 and is realized by, for example, a liquid crystal display (LCD).

  The diagnosis device 20 operates according to an abnormality determination processing program stored in the storage unit 22, and the abnormality determination processing according to the embodiment is realized by the abnormality determination processing program.

  The diagnostic device 20 is detected by the vibration detection signal including information on the vibration detected by the vibration sensor 12, the rotation speed detection signal including information on the rotation speed detected by the rotation speed sensor 13, and the power generation amount sensor 14. A power generation amount detection signal including information on the power generation amount is input. The diagnostic device 20 performs an abnormality determination process for the spindle bearing 41 based on the vibration detection signal, the rotation speed detection signal, and the power generation amount detection signal.

  FIG. 5 is a schematic diagram illustrating an example of the abnormality determination process. The abnormality determination process shown in FIG. 5 is executed by, for example, the processing unit 21 shown in FIG. 6 is an image diagram showing the relationship between the rotational speed of the wind power generator and the frequency band in the abnormality determination process shown in FIG. The relationship between the rotation speed and the frequency band illustrated in FIG. 6 is stored in the storage unit 22 of the diagnostic device 20, for example. The relationship between the rotation speed and the frequency band stored in the storage unit 22 may be numerical data or may be a discrete value such as digital data.

  The diagnosis device 20 receives the vibration detection signal, the rotation speed detection signal, and the power generation amount detection signal output from the detection device 10. Specifically, a vibration detection signal, a rotation speed detection signal, and a power generation amount detection signal are input from the detection device 10 to the processing unit 21 via the communication unit 23 illustrated in FIG.

  The processing unit 21 reads data indicating the relationship between the rotation speed and the frequency band shown in FIG. 6 stored in the storage unit 22, and sets the frequency band for performing the abnormality determination process. Specifically, the processing unit 21 uses a frequency band higher than the first frequency b1 and lower than the second frequency b2 as a passband and a frequency band higher than the third frequency b3 as a passband. One or both of the second frequency bands FW2 to be set are set as frequency bands for performing the abnormality determination process. The processing unit 21 performs the band limiting process S1 of the vibration detection signal in the set frequency band.

  In the present embodiment, the third frequency b3 is higher than the second frequency b2. That is, the relationship between the first frequency b1, the second frequency b2, and the third frequency b3 is expressed by the following equation (1).

  b1 <b2 <b3 (1)

  The definitions of the first frequency b1, the second frequency b2, and the third frequency b3 will be described later.

  Subsequently, the processing unit 21 performs a calculation process S2 as a result of the band limiting process S1. For example, the processing unit 21 calculates the effective value of the frequency component in one or both of the first frequency band FW1 set in the band limiting process S1 and the second frequency band FW2 set in the band limiting process S1. Perform processing.

  Subsequently, the processing unit 21 performs the primary determination process S3 in the abnormality determination process of the spindle bearing 41 based on the result of the calculation process S2. The determination criterion for the presence or absence of abnormality in the primary determination process S3 is based on, for example, a threshold value of an effective value set in advance for each frequency band. When it is determined that there is no abnormality in the primary determination process S3, the result of the primary determination process S3 is output. Specifically, the processing unit 21 outputs the result of the primary determination process S3 to the display unit 25, for example.

  When it determines with abnormality by primary determination process S3, the process part 21 performs vibration analysis process S4 based on the result of calculation process S2. Specifically, the processing unit 21 performs an envelope (envelope) process of digital data obtained by AD-converting an analog value with respect to the frequency band set in the band limiting process S1, and performs high-speed processing on the data after the envelope process. The vibration analysis process S4 is performed by Fourier transform (FFT: Fast Fourier Transform).

  Subsequently, the processing unit 21 performs a secondary determination process S5 in the abnormality determination process of the spindle bearing 41 based on the vibration analysis process S4. The presence / absence of abnormality is determined based on, for example, the degree of coincidence between the theoretical frequency of the bearing and the characteristic frequency of the vibration analysis result, but the present disclosure is not limited.

  Subsequently, the processing unit 21 outputs the result of the secondary determination process S5. Specifically, the processing unit 21 outputs the results of the primary determination process S3 and the secondary determination process S5 to the display unit 25, for example. The display mode displayed on the display unit 25 may be, for example, a display mode indicating whether the main shaft bearing 41 is abnormal or normal, in other words, whether the main shaft bearing 41 is damaged. . Further, a display mode may be used that displays various data such as the amount of power generation, the frequency band, and the result of the vibration analysis process S4 when the abnormality determination process is performed.

  Further, for example, the processing unit 21 stores various data such as the results of the primary determination process S3 and the secondary determination process S5, or the rotation speed, the frequency band when the abnormality determination process is performed, and the result of the vibration analysis process S4. It outputs to 22 and memorize | stores it. In this way, the administrator of the wind power generator 100 operates the input unit 24 to store the results of the primary determination process S3 and the secondary determination process S5 stored in the storage unit 22, and various data during the abnormality determination process. Over time can be displayed on the display unit 25. In addition, the administrator of the wind power generator 100 operates the input unit 24 to display the results of the primary determination process S3 and the secondary determination process S5 stored in the storage unit 22, and the changes over time in various data during the abnormality determination process. And can be output via the communication unit 23. Thereby, the damage degree of the main shaft bearing 41 of the wind power generator 100 and the process up to the damage can be easily grasped.

  Next, the concept of the abnormality determination process in this embodiment will be described.

  In the wind power generator 100, it is considered that the impact vibration when the main shaft bearing 41 is damaged has a large load applied to the main shaft bearing 41 and can excite the structural system including the casing 501 of the gearbox 50.

  On the other hand, the meshing vibration of the gear inside the gearbox 50 propagates to the spindle bearing housing 42 provided with the vibration sensor 12. For this reason, in the case where the vibration frequency of the impact vibration due to the damage of the main shaft bearing 41 and the vibration frequency due to disturbance elements such as the meshing vibration of the gear inside the gearbox 50 are close to each other, the main shaft bearing There is a possibility that the detection accuracy of the damage 41 is lowered.

  Here, the teeth provided on the outer peripheral surface of the first gear of the speed increaser 50, that is, the planetary gear 510, are provided on the outer peripheral surface of the sun gear 508 and the inner peripheral surface of the ring gear 509, respectively. A gear mechanism configured by meshing the teeth is referred to as a “first gear mechanism”. The second gear of the speed increaser 50, that is, the input gear 524 provided on the low-speed shaft 505 and the first intermediate gear 525 provided on the outer peripheral surface of the intermediate portion of the intermediate shaft 506 are meshed. This gear mechanism is referred to as a “second gear mechanism”. The inventor of the present disclosure limits the frequency band between the primary component of the frequency of meshing vibration in the first gear mechanism and the primary component of the frequency of meshing vibration in the second gear mechanism to perform vibration analysis processing. It has been found that it is easier to catch signs of damage to the spindle bearing 41 by performing the above.

  In the present embodiment, a frequency higher than the primary component of the frequency of meshing vibration in the first gear mechanism is set as the first frequency b1 shown in FIG. The first frequency b1 [Hz] is as follows when the number of teeth of the sun gear 508 is Ts [number], the number of teeth of the ring gear 509 is Tr [number], and the rotational frequency of the sun gear 508 is fs [Hz]. It is represented by the formula (2).

  b1> (Ts × Tr / (Ts + Tr)) × fs (2)

  The first frequency b1 [Hz] is expressed by the following equation (3) when the revolution frequency of the planetary gear 510 is fc [Hz].

  b1> Tr × fc (3)

  In the present embodiment, the frequency lower than the primary component of the meshing vibration frequency in the second gear mechanism is set as the second frequency b2 shown in FIG. The second frequency b2 [Hz] is expressed by the following equation (4) when the number of teeth of the input gear 524 is T3 [pieces] and the rotation speed is R3 [rps].

  b2 <T3 × R3 (4)

  The second frequency b2 [Hz] is expressed by the following equation (5) when the number of teeth of the first intermediate gear 525 is T4 [pieces] and the rotation speed is R4 [rps].

  b2 <T4 × R4 (5)

  The rotational speed of the sun gear 508, the rotational speed of the ring gear 509, the rotational speed of the input gear 524, and the rotational speed of the first intermediate gear 525 are the rotational speed of the main shaft 40, in other words, the rotational speed of the wind power generator 100. Proportional. That is, the first frequency b1 and the second frequency b2 may be set so as to change in proportion to the rotational speed a of the wind power generator 100 as shown in FIG. In the band limiting process S1 shown in FIG. 5, the frequency band in which the subsequent vibration analysis process S4 is performed is set to a first frequency band FW1 that is higher than the first frequency b1 and lower than the second frequency b2. Thereby, the primary component of the frequency of the meshing vibration in the first gear mechanism and the primary component of the frequency of the meshing vibration in the second gear mechanism can be suppressed.

  In addition, shock vibration from the blade 32 propagates to the main shaft bearing housing 42 provided with the vibration sensor 12, and this shock vibration is cited as one of disturbance elements that greatly hinders vibration analysis of the main shaft bearing 41. The vibration level and occurrence frequency of the impact vibration propagating from the blade 32 are different for each wind power generator 100. Further, the impact vibration propagating from the blade 32 is higher than the primary component of the frequency component of the meshing vibration of the first gear mechanism and the primary component of the frequency component of the meshing vibration of the second gear mechanism. Excited in a high, approximately several kHz band.

  In the present embodiment, a frequency higher than the frequency of the vibration excited by the impact vibration propagating from the blade 32 is set as the third frequency b3 shown in FIG. The frequency of the vibration excited by the impact vibration propagating from the blade 32 does not depend on the rotation speed, and the generated frequency band is substantially constant. That is, the third frequency b3 may be set to a constant frequency that does not depend on the rotational speed a of the wind power generator 100 as shown in FIG. In the band limiting process S1 shown in FIG. 5, the frequency band in which the subsequent vibration analysis process S4 is performed is set to the second frequency band FW2 higher than the third frequency b3, thereby being excited by the impact vibration propagating from the blade 32. The frequency component of vibration can be suppressed.

  When the amount of power generated by the wind power generator 100 is relatively small, the load zone is stable due to the weight of the rotor 30, so that the impact vibration due to damage to the main shaft bearing 41 is stabilized. Further, since disturbance elements such as meshing vibrations of gears inside the gearbox 50 are also suppressed, the abnormality determination processing is performed when the power generation amount of the wind power generator 100 is relatively small. Can be detected with high accuracy.

  For this reason, for example, a predetermined power generation amount threshold value Wth may be provided for the power generation amount of the wind power generator 100 as one of determination criteria for performing the abnormality determination process. The power generation amount threshold value Wth may be stored in the storage unit 22 of the diagnostic device 20, for example. The relationship between the rotation speed and the frequency band stored in the storage unit 22 may be numerical data or may be a discrete value such as digital data. The power generation threshold Wth is expressed by the following equation (6), where W is the power generation amount of the wind power generator 100.

  W ≦ Wth (6)

  It is desirable that the power generation amount threshold value Wth be an upper limit value that can detect damage to the main shaft bearing 41 and that the abnormality determination process is not performed when the above formula (6) is not satisfied.

  FIG. 7A is a diagram illustrating an effective value calculation process result of a vibration analysis process result depending on the presence / absence of a band limitation process.

  (A) shown to FIG. 7A has shown the effective value calculation process result of the vibration analysis process result when not performing a band limitation process.

  (B) shown to FIG. 7A has shown the effective value calculation process result of the vibration analysis process result at the time of carrying out band limitation to the 1st frequency band FW1 shown in FIG.

  (C) shown in FIG. 7A shows the effective value calculation processing result of the vibration analysis processing result when the band is limited to the second frequency band FW2 shown in FIG.

  In the RMS value calculation result of the vibration analysis process result when the band limiting process shown in FIG. 7A is not performed, the error bar indicating the standard deviation of the RMS value has a large width, so the abnormality determination process for the spindle bearing 41 is performed. May cause false detection. On the other hand, in the effective value calculation processing results of the vibration analysis processing results shown in (b) of FIG. 7A and (c) of FIG. 7A, the error bar indicating the standard deviation of the effective value is clear while the difference of the effective value itself is clear. Since the width is small, vibration changes indicating signs of damage to the spindle bearing 41 are captured with high sensitivity. FIG. 7B is an enlarged view of (b) and (c) of FIG. 7A in the effective value direction.

  FIG. 8A is a diagram illustrating an effective value calculation process result of a vibration analysis process result depending on whether or not a band limiting process is performed when the power generation amount of the wind power generator is relatively small.

  (A) shown to FIG. 8A has shown the effective value calculation process result of the vibration analysis process result when not performing a band limitation process.

  (B) shown in FIG. 8A shows the effective value calculation processing result of the vibration analysis processing result when the band is limited to the first frequency band FW1 shown in FIG.

  (C) shown in FIG. 8A shows the effective value calculation processing result of the vibration analysis processing result when the band is limited to the second frequency band FW2 shown in FIG.

  As shown in (a), (b), and (c) of FIG. 8A, when the power generation amount of the wind power generator 100 is relatively small, the width of the error bar indicating the standard deviation of the effective value is small. It can be seen that the vibration change of the spindle bearing 41 is better captured as compared to the example shown in FIG. In particular, in (b) and (c) of FIG. 8A in which frequency components due to disturbance elements are removed, not only the width of the error bar indicating the standard deviation of the effective value but also the difference in the effective value itself appears more clearly. . FIG. 8B is an enlarged view of (b) and (c) of FIG. 8A in the effective value direction.

  Thus, in order to capture the signs of damage to the main shaft bearing 41, the above-described band limiting process is effective. By suppressing the vibration component due to the disturbance element, the vibration change indicating the signs of damage to the main shaft bearing 41 can be performed. Can be captured with good sensitivity. In particular, when the power generation amount is relatively small, the abnormality determination process of the spindle bearing 41 with higher sensitivity can be performed by suppressing the vibration component due to the disturbance element and performing the subsequent process.

  When the amount of power generated by the wind power generator 100 is large, the position of the load zone of the main shaft bearing 41 may change due to the moment applied to the main shaft bearing 41, and the damaged portion of the main shaft bearing 41 may become unloaded. . In this case, the impact vibration when the rolling element of the main shaft bearing 41 passes through the damaged portion does not occur, and a frequency component indicating an indication of damage to the main shaft bearing 41 may not occur. Therefore, it is desirable to perform the abnormality determination process for the main shaft bearing 41 within a range where the power generation amount W of the wind power generator 100 is equal to or less than the predetermined power generation amount threshold value Wth expressed by the above equation (6).

  FIG. 9 is a diagram illustrating an example of a frequency analysis result in the abnormality detection system for the main shaft bearing of the wind power generator according to the embodiment. In the present embodiment, as described above, by limiting the band to one or both of the first frequency band FW1 and the second frequency band FW2 illustrated in FIG. 6, damage to the main shaft bearing 41 is performed as illustrated in FIG. It becomes easy to catch the frequency component which shows the sign of.

  As described above, in the present embodiment, one or both of the first frequency band FW1 and the second frequency band FW2 illustrated in FIG. 6 is set as a frequency band for performing the abnormality determination process. Thereby, when performing the abnormality determination process of the main shaft bearing 41 of the wind power generator 100, the vibration frequency due to disturbance elements other than the vibration frequency of the impact vibration due to the damage of the main shaft bearing 41 is suppressed, and the main shaft bearing 41 is not damaged. Detection accuracy is improved.

  Furthermore, when the power generation amount W of the wind power generator 100 is equal to or less than the predetermined power generation amount threshold value Wth, it is possible to perform the abnormality determination process for the spindle bearing 41 with higher sensitivity by performing the subsequent processing.

  Note that the conditions for performing the abnormality determination process for the main shaft bearing 41 of the wind power generator 100 are not limited to the power generation amount of the wind power generator 100, but may be other conditions indicating the operating state of the wind power generator 100. good. Examples of such conditions include the rotational speed of the main shaft 40 and the output shaft 61 (the generator 60).

  FIG. 10 is a flowchart illustrating an example of an abnormality determination processing procedure according to the embodiment. Hereinafter, according to the flowchart shown in FIG. 10, the abnormality determination processing procedure according to the embodiment will be described.

  First, the processing unit 21 of the diagnostic device 20 acquires a vibration detection signal, a rotation speed detection signal, and a power generation amount detection signal from the detection device 10 (step S101).

  Subsequently, the processing unit 21 extracts the power generation amount W of the wind power generator 100 from the power generation amount detection signal (step S102).

  The processing unit 21 determines whether or not the power generation amount W of the wind power generator 100 extracted in step S102 is equal to or less than the power generation amount threshold Wth (W ≦ Wth) (step S103). When the power generation amount W of the wind power generator 100 is equal to or less than the power generation amount threshold Wth (step S103; Yes), the process proceeds to step S104. When the power generation amount W of the wind power generator 100 is larger than the power generation amount threshold Wth (step S103; No), the process returns to step S101, and the processes of steps S101 and S102 are repeated.

  The processing unit 21 performs the band limitation process of the vibration detection signal in one or both of the first condition and the second condition set in step S103 (step S104).

  Subsequently, the processing unit 21 performs a calculation process S2 as a result of the band limitation process S1 (step S105). For example, the processing unit 21 performs an effective value calculation process for the frequency band set in the band limiting process S1.

  Subsequently, the processing unit 21 performs the primary determination process S3 in the abnormality determination process of the main shaft bearing 41 based on the result of the calculation process S2 (step S106). When it is determined by the primary determination process S3 that there is no abnormality (step S106; No), as a result of the primary determination process S3, the main shaft bearing 41 is assumed to be normal, and the determination process result is output (step S109). The process returns to S101.

  When it determines with abnormality by primary determination process S3 (step S106; Yes), the process part 21 performs vibration analysis process S4 based on the result of calculation process S2 (step S107). Specifically, the processing unit 21 performs an envelope (envelope) process of digital data obtained by AD-converting an analog value with respect to the frequency band set in the band limiting process S1, and performs high-speed processing on the data after the envelope process. The vibration analysis process S4 is performed by Fourier transform (FFT: Fast Fourier Transform).

  Subsequently, the processing unit 21 performs the secondary determination process S5 in the abnormality determination process of the spindle bearing 41 based on the vibration analysis process S4 (step S108). If it is determined by the secondary determination process S5 that there is no abnormality (step S108; No), the result of the secondary determination process S5 is that the spindle bearing 41 is normal, and the determination process result is output (step S109). The process returns to step S101.

  If it is determined that there is an abnormality in the secondary determination process S5 (step S108; Yes), it is determined that an abnormality of the main shaft bearing 41 has been detected, and the determination process result is output (step S110), and the process returns to step S101.

  By repeatedly executing the abnormality determination process described above, it is possible to improve the accuracy of detecting damage to the spindle bearing 41.

  In the present embodiment, the mode in which the effective value calculation process is performed in the calculation process S2 has been described. However, for example, a mode in which a partial overall value is calculated may be used.

  In the above-described embodiment, the first frequency is set higher than the primary component of the vibration frequency generated by the first gear mechanism, and the second frequency is the primary frequency of the vibration generated by the second gear mechanism. The aspect which makes it lower than a component was shown. As another aspect, the first frequency is higher than the m-order component of the frequency of vibration generated by the first gear mechanism (m is a natural number of 1 or more), and the second frequency is generated by the second gear mechanism. The aspect which makes it lower than the n-order component (n is a natural number greater than or equal to 1) of the frequency of may be sufficient.

  As described above, the abnormality detection system and abnormality detection method for the main shaft bearing of the wind power generator according to the embodiment sets the frequency band for determining the information on the vibration detected by the detection device 10, and the set frequency band The abnormality determination process of the main shaft bearing 41 is performed based on the vibration information limited to.

  Thereby, when performing the abnormality determination process of the main shaft bearing 41 of the wind power generator 100, the frequency component of vibration due to disturbance elements other than the vibration frequency of the impact vibration due to the damage of the main shaft bearing 41 is suppressed, and the main shaft bearing 41 Damage detection accuracy is improved.

  Specifically, in the configuration including the first gear mechanism and the second gear mechanism, the vibration generated by the second gear mechanism is higher than the primary component of the frequency of vibration generated by the first gear mechanism. A first frequency band lower than the primary component of the frequency is set as a frequency band for performing the abnormality determination process of the main shaft bearing 41. Thereby, the primary component of the frequency of vibration generated in the first gear mechanism and the primary component of the frequency of vibration generated in the second gear mechanism are suppressed.

  In addition, a second frequency band higher than the frequency of the vibration excited by the impact vibration propagating from the blade 32 of the wind power generator 100 is set as a frequency band for performing the abnormality determination process of the main shaft bearing 41. Thereby, the frequency component of the vibration excited by the impact vibration propagating from the blade 32 of the wind power generator 100 is suppressed.

  Thus, according to this embodiment, the abnormality detection system and abnormality detection method of the main shaft bearing of a wind power generator which can raise the detection accuracy of the damage of the main shaft bearing of a wind power generator are obtained.

DESCRIPTION OF SYMBOLS 1 Wind power generation system 10 Detection apparatus 11 Data collection part 12 Vibration sensor 13 Rotational speed sensor 14 Electric power generation amount sensor 20 Diagnosis apparatus 21 Processing part 22 Storage part 23 Communication part 24 Input part 25 Display part 26 Bus 30 Rotor 31 Hub 32 Blade 40 Spindle 41 Main shaft bearing 42 Main shaft bearing housing 43 Coupling 50 Speed up gear 51 Input shaft 52 Input shaft bearing 53 Torque arm 60 Generator 61 Output shaft 70 Nacelle 80 Tower 90 Base (frame)
DESCRIPTION OF SYMBOLS 100 Wind power generator 200 Network 501 Case 502 Planetary gear apparatus 503 Secondary speed increasing apparatus 505 Low speed shaft 506 Intermediate shaft 508 Sun gear 509 Ring gear 510 Planetary gear 511 Planetary shaft 512 Cylindrical roller bearing 513 Carrier 524 Input gear 525 First intermediate Gear 526 Second intermediate gear 527 Output gear FW1 First frequency band FW2 Second frequency band

Claims (9)

A detection device for detecting the vibration of the main shaft bearing of the wind power generator;
A diagnostic device that sets a frequency band for determining vibration information detected by the detection device and performs abnormality determination processing for the spindle bearing based on vibration information limited to the set frequency band;
An abnormality detection system for a main shaft bearing of a wind power generator. The detection device includes:
Detecting the rotational speed of the wind power generator,
The diagnostic device comprises:
The abnormality detection system for the main shaft bearing of the wind power generator according to claim 1, wherein a frequency band for performing the abnormality determination process is set according to the rotation speed. The diagnostic device comprises:
A first frequency band higher than the first frequency and having a frequency band less than the second frequency higher than the first frequency as a pass band, and a frequency not including the first frequency band and higher than the third frequency The abnormality detection system for a main shaft bearing of a wind power generator according to claim 1 or 2, wherein either or both of the second frequency bands having a band as a pass band are set as frequency bands for performing the abnormality determination process. The wind power generator
Having a plurality of gear mechanisms configured by meshing gears provided on two rotating shafts;
The plurality of gear mechanisms are
A first gear mechanism;
A second gear mechanism;
Including
The first frequency is higher than a primary component of a frequency of vibration generated in the first gear mechanism,
The abnormality detection system for a main shaft bearing of a wind power generator according to claim 3, wherein the second frequency is lower than a primary component of a frequency of vibration generated in the second gear mechanism. The wind power generator
Having a plurality of gear mechanisms configured by meshing gears provided on two rotating shafts;
The plurality of gear mechanisms are
A first gear mechanism;
A second gear mechanism;
Including
The first frequency is higher than an m-order component (m is a natural number of 1 or more) of a frequency of vibration generated in the first gear mechanism,
The abnormality detection system for a main shaft bearing of a wind power generator according to claim 3, wherein the second frequency is lower than an nth-order component (n is a natural number of 1 or more) of a frequency of vibration generated in the second gear mechanism. The abnormality detection system for a main shaft bearing of a wind power generator according to any one of claims 3 to 5, wherein the third frequency is higher than a frequency of vibration excited by impact vibration propagating from a blade of the wind power generator. . The diagnostic device comprises:
The abnormality detection of the main shaft bearing of the wind power generator as described in any one of Claim 1 to 6 which performs the primary determination process in the said abnormality determination process based on the effective value or partial overall value of the vibration restrict | limited to the said frequency band. system. The diagnostic device comprises:
8. When an abnormality is detected in the primary determination process, an analysis process of vibration limited to the frequency band is performed, and a secondary determination process in the abnormality determination process is performed based on a result of the analysis process. An abnormality detection system for the main shaft bearing of the described wind power generator. Setting a frequency band for determining vibration information of the main shaft bearing of the wind power generator;
Based on the effective value or partial overall value of vibration limited to the set frequency band, performing a primary determination process of the spindle bearing;
When an abnormality is detected in the primary determination process, performing a vibration analysis process limited to the frequency band, and performing a secondary determination process of the spindle bearing based on the result of the analysis process;
Outputting the result of the primary determination process or the secondary determination process;
An abnormality detection method for a main shaft bearing of a wind power generator.

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