Measurement device, measurement method and program

Abstract

To provide a method for measuring clearance between a rotating body and a casing of a rotary machine, accurately and in a non-contact manner.SOLUTION: A measurement device is provided, which measures clearance between a rotating body of a rotary machine and a casing enclosing the rotating body, the measurement device comprises: a means of acquiring measurement data on the intensity of reflected light of light emitted from the rotating body in rotation to the casing and measurement data on the distance between the casing and the rotating body based upon the reflected light; a means of removing spike-shaped noise from the acquired measurement data on the distance based upon the measurement data on the intensity of the reflected light; and a means of performing statistical processing on a plurality of pieces of measurement data on the distance after the noise removal and calculating measured values of the clearance.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a measurement apparatus, a measurement method, and a program. [Background technology]

[0002] In rotating machinery such as steam turbines, gas turbines, and compressors, the clearance between the tips of the rotor blades and the inner circumferential surface of the casing that surrounds the rotor blades affects performance. Therefore, it is important to measure the clearance when assembling the rotating machinery, during test runs, and during regular inspections, and to check whether it is an appropriate value.

[0003] Regarding the measurement of the clearance, Patent Document 1 discloses a method of inserting a contact sensor from an opening formed in a casing and pressing the tip of the sensor against a moving blade to measure the clearance. In the method described in Patent Document 1, the rotor is rotated at a low speed while the sensor is brought into contact with the moving blade to measure the clearance, which may cause deformation or damage. In contrast, Patent Document 2 discloses a system in which a light source installed in the casing irradiates light onto the moving blade and receives the reflected light to measure the clearance. In the method described in Patent Document 2, the clearance can be measured without contact, which can prevent damage to the blade and the sensor, but if the noise contained in the reflected light is not properly handled, the measurement accuracy will decrease. In addition, Patent Document 3 discloses a sensor installation structure that allows a sensor for measuring the clearance to be attached so that it can be inserted and removed from the outside of the casing. According to this installation structure, it is not necessary to open or disassemble the casing, and it is possible to install and remove a sensor for measuring the clearance, regardless of whether it is a contact type or a non-contact type. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5984648 [Patent Document 2] Patent No. 6959027 [Patent Document 3] Patent No. 4476116 Summary of the Invention [Problem to be solved by the invention]

[0005] There is a need for a method that can measure the clearance between the rotor blades and the casing non-contact and with high accuracy.

[0006] The present disclosure provides a measurement device, a measurement method, and a program that can solve the above problems. [Means for solving the problem]

[0007] The measuring device disclosed herein is a measuring device that measures the clearance between a rotating body in a rotating machine and a casing surrounding the rotating body, and includes: means for acquiring measurement data of the intensity of reflected light of light irradiated from the casing to the rotating body while rotating, and measurement data of the distance between the casing and the rotating body based on the reflected light; means for removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light; and means for statistically processing a plurality of the distance measurement data after noise removal, and calculating a measurement value of the clearance.

[0008] The measurement method disclosed herein is a method for measuring a clearance between a rotating body in a rotating machine and a casing surrounding the rotating body, and includes the steps of: acquiring measurement data of the intensity of reflected light of light irradiated from the casing to the rotating body while rotating, and measurement data of the distance between the casing and the rotating body based on the reflected light; removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light; and statistically processing the multiple distance measurement data after noise removal to calculate a measurement value of the clearance.

[0009] In addition, the program disclosed herein causes a computer to execute a measurement process for measuring a clearance between a rotating body in a rotating machine and a casing surrounding the rotating body, the measurement process including the steps of acquiring measurement data of the intensity of reflected light of light irradiated from the casing to the rotating body while rotating and measurement data of the distance between the casing and the rotating body based on the reflected light, removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light, and statistically processing the multiple distance measurement data after noise removal to calculate a measurement value of the clearance. Effect of the Invention

[0010] According to the above-described measuring device, measuring method, and program, it is possible to measure the clearance between the tip of a rotating body, such as a rotor blade in a rotary machine, and a casing that houses the rotating body in a non-contact manner with high accuracy. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating an example of a measurement device according to an embodiment. [Diagram 2] 1 is a diagram showing an overview of a confocal sensor according to an embodiment; [Diagram 3] 1 is a schematic cross-sectional view of a rotating machine according to an embodiment; [Figure 4] FIG. 2 is a first diagram showing an example of measurement data according to the embodiment. [Diagram 5] FIG. 2 is a second diagram showing an example of measurement data according to the embodiment. [Figure 6] FIG. 11 is a third diagram showing an example of measurement data according to the embodiment. [Figure 7] FIG. 13 is a diagram showing an example of a frequency distribution of clearance measurement data according to the embodiment. [Figure 8] 10 is a flowchart illustrating an example of a clearance measurement process according to the embodiment. [Figure 9] FIG. 2 is a diagram illustrating an example of a hardware configuration of a measurement apparatus according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] <Embodiment> A clearance measurement device according to an embodiment will be described with reference to the drawings. In the drawings used in the following description, the configuration of parts that are not related to the present disclosure may be omitted or not illustrated.

[0013] (composition) Fig. 1 is a diagram showing an example of a measuring device according to an embodiment, illustrating a block diagram of a measuring device 10 and a schematic diagram of a rotating machine 100 to be measured. As shown in the figure, the measurement device 10 includes a sensor 11, a measurement data acquisition unit 12, a division unit 13, a noise removal unit 14, a clearance measurement unit 15, and a storage unit 16. The sensor 11 is a sensor that measures the distance to an object in a non-contact manner by irradiating the object with light and receiving the light reflected from the object. For example, the sensor 11 is installed so as to irradiate light from a predetermined position along the inner circumferential surface 31 of the casing 3 in the rotating machine 100, and measures the distance from that position to the rotor blade 2 and the intensity of the light reflected by the rotor blade 2. The measurement data acquisition unit 12 acquires the measurement data measured by the sensor 11. The measurement data includes a measurement value of distance and a measurement value of light intensity. The dividing unit 13 divides the measurement data acquired by the measurement data acquiring unit 12 for each rotor blade 2 . The noise removal unit 14 removes noise from the measurement data. The clearance measurement unit 15 calculates the clearance α for each rotor blade 2 from the measurement data for each rotor blade 2 after noise has been removed. The storage unit 16 stores the measurement data acquired by the measurement data acquisition unit 12 and various data processed by the division unit 13, the noise removal unit 14, and the clearance measurement unit 15. Using these functions, the measurement device 10 measures the clearance α, which is the distance between the tip of the rotor blade 2 and the casing 3. The sensor 11, the dividing unit 13, the noise removing unit 14, and the clearance measuring unit 15 will be described in more detail later.

[0014] A rotary machine 100 such as a compressor or a turbine includes a rotor 1 extending along an axis A, multiple stages of rotor blades 2 spaced apart on the outer circumferential surface of the rotor 1 in the direction of the axis A, a casing 3 covering the rotor 1 from the outer circumferential side, and multiple stages of stator blades 4 spaced apart on the inner circumferential surface 31 of the casing 3 in the direction of the axis A. The rotor 1 is supported by a bearing device (not shown) so as to be rotatable about the axis A. The sensor 11 is inserted from the outside of the casing 3 toward the inner circumferential surface 31 through an opening provided in the casing 3, and is installed so as to irradiate light from a position along the inner circumferential surface 31. For installation of the sensor 11, for example, a method disclosed in Patent Document 3 can be applied.

[0015] The sensor 11 is, for example, a confocal sensor. An overview of the confocal sensor 110 is shown in FIG. 2. The confocal sensor 110 is a sensor that irradiates a plurality of wavelengths of light with different focal lengths onto an object 200 and measures the distance to the object 200 from the wavelength of the reflected light. The confocal sensor 110 includes a light source 111, a beam splitter 112, a lens 113, a member 114 with a pinhole, a spectrometer 115, and the like. The beam splitter 112 is made of glass that transmits half of the incident light and reflects the other half, and is used to extract the reflected light 117 that returns via the same path as the light 111a from the light source 111. Half of the light 111a irradiated by the light source 111 passes through the beam splitter 112, and the wavelength is resolved by the lens 113 and irradiated onto the object 200. The light of each wavelength resolved by the lens 113 is adjusted to be focused at a predetermined distance, for example, light 116a of wavelength 1 is L1 mm, light 116b of wavelength 2 is L2 mm, light 116c of wavelength 3 is L3 mm, light 116d of wavelength 4 is L4 mm, etc. Then, for example, if the distance from the lens 113 to the object 200 is just L3 mm, only the reflected light 117 of the light 116c is guided by the beam splitter 112 to pass through the pinhole of the member 114, and the distance L3 is measured by detecting the wavelength 3 of the reflected light 117 by the spectrometer 115. The output of the confocal sensor 110 is the distance from the confocal sensor 110 to the object 200 and the intensity of the reflected light of the wavelength passing through the pinhole from the object 200.

[0016] For example, if the object 200 is coated for heat insulation purposes, the confocal sensor 110 outputs the distance and light intensity from the coating surface of the object 200, and the distance and light intensity from the confocal sensor 110 to the object 200. In this case, a required value is selected according to the purpose. For example, in this example, the intensity of light reflected by the object 200 is greater than that of the coating surface. Therefore, if it is desired to measure the distance to the object 200, the measurement value of the distance obtained together with the measurement value with the greater light intensity is adopted from among the measurement values ​​output from the confocal sensor 110.

[0017] As will be described below, in the measurement device 10, the measurement data acquisition unit 12 acquires the distance and light intensity measured by the sensor 11 (for example, the confocal sensor 110), and extracts data to be evaluated by dividing the measurement data using the division unit 13 and removing noise using the noise removal unit 14, focusing on the light intensity. Then, the clearance measurement unit 15 calculates the clearance α based on the extracted measurement data of the distance.

[0018] 1, as an example, the sensor 11 is provided for one stage of rotor blades 2, but the sensor 11 may be provided for each of all rotor blade stages, or the sensor 11 may be provided for a plurality of representative rotor blade stages to measure the clearance α of the rotor blades 2 constituting the representative rotor blade stages. Note that a rotor blade stage refers to a set of a plurality of rotor blades 2 provided around one circumference of the rotor 1 at the same position in the direction of the axis A.

[0019] FIG. 3 is a schematic diagram of a cross section of a rotary machine 100 when one of a plurality of rotor blade stages is focused on. As illustrated in FIG. 3, one rotor blade stage includes a plurality of rotor blades 2a, 2b, 2c, etc., arranged at intervals in the circumferential direction of an axis A. For example, when the rotor 1 rotates in the direction of the arrow, the clearance α of the rotor blade 2b is measured while the rotor blade 2b passes through the measurement range of the sensor 11, but between the rotor blade 2b and the rotor blade 2c, the distance from the inner peripheral surface 31 of the casing 3 to the outer peripheral surface of the rotor 1 is measured, and when the rotor blade 2c reaches a position where it passes through the measurement range of the sensor 11 again, the clearance α of the rotor blade 2c is measured this time. The measuring device 10 manually or automatically rotates the rotor 1 at a low speed, causes the sensor 11 to measure the distance and light intensity at a predetermined sampling period during the rotation, and accumulates the measurement data. Then, statistical processing is performed on the accumulated measurement data to measure the clearance α for each rotor blade 2, such as clearance α for rotor blade 2a, clearance α for rotor blade 2b, clearance α for rotor blade 2c, etc. An example of the measurement data of the distance measured by sensor 11 while rotor 1 is rotating is shown in Figure 4.

[0020] FIG. 4 is a graph showing distance measurement data among the measured values ​​of distance and light intensity outputted when a certain rotor blade stage is measured by the sensor 11 while the rotor 1 is rotated manually at a low speed. The vertical axis of the graph in FIG. 4 shows distance, and the horizontal axis shows time. 41a to 41l shown in the figure are time periods during which any of the rotor blades 2 constituting the rotor blade stage to be measured enters the measurement range of the sensor 11 as the rotor 1 rotates. Because the rotation is manual, there is variation in the rotation speed, and the time lengths of 41a to 41l are different. The values ​​on the graph during these time periods are the clearance α of the rotor blade 2 passing through the measurement range of the sensor 11. 42a to 42l surrounded by circles show the minimum value of the clearance measured for one rotor blade 2. The time periods other than 41a to 41l are time periods during which the space between the rotor blade 2 and the next rotor blade 2 is within the measurement range of the sensor 11, and at these times, the distance from the inner peripheral surface 31 of the casing 3 to the outer peripheral surface of the rotor 1 is measured. The dividing unit 13 divides the distance measurement data and the light intensity measurement data acquired by the measurement data acquiring unit 12 for each rotor blade 2 .

[0021] (Dividing measurement data) Next, the division of the measurement data will be described with reference to FIG. 5. FIG. 5 shows the transition of the distance and the light intensity measured by the sensor 11 in a time series. The vertical axis of the graph in FIG. 5 is the distance or the light intensity, and the horizontal axis is the time. Graph 51 shows the transition of the distance, and graph 52 shows the transition of the light intensity. The light intensity measured by the sensor 11 increases when the rotor blade 2 reaches the measurement range of the sensor 11, shows a value above a certain value while the rotor blade 2 is passing, and becomes 0 after the rotor blade 2 passes the measurement range. The threshold value 53 (sometimes called the first threshold value) in FIG. 5 is a threshold value for detecting that the rotor blade 2 has reached the measurement range of the sensor 11. The measurement data of the distance measured when the light intensity is equal to or greater than the threshold value 53 is used to evaluate the clearance α. In addition, when the light intensity is equal to or greater than the threshold value 53, a trigger is turned ON, and when the light intensity falls below the threshold value 53 after the trigger is turned ON, the trigger is kept ON for a predetermined trigger holding time 54. The trigger ON state refers to a state in which a certain blade 2 enters the measurement range of the sensor 11 and passes through it completely. In other words, during the trigger ON state, the next blade 2 is not considered to have arrived at the measurement range, regardless of the value of the light intensity. As a result, even if the light intensity momentarily drops below the threshold 53 and immediately returns to above the threshold 53, the measurement data obtained during this period can be regarded as related to the same blade 2, and when dividing the measurement data for each blade 2, confusion with measurement data for another blade 2 can be prevented. In summary, the division unit 13 divides the time-series measurement data acquired by the measurement data acquisition unit 12 for each blade 2 by treating the measurement data for a certain time period, which is extracted by the following algorithms (1) to (3), as measurement data for one blade 2, based on the light intensity of the measurement values ​​obtained by the sensor 11. (1) The measurement data of the distance at the time when the light intensity is equal to or greater than the first threshold (threshold 53) is used as the target for clearance evaluation. (2) When the light intensity exceeds the first threshold, the trigger is turned ON. (3) When a predetermined trigger hold time 54 has elapsed since the light intensity fell below the first threshold, the trigger is turned OFF, and it is determined that the blade 2 has finished passing.

[0022] The dividing unit 13 divides the measurement data according to the above (1) to (3), and stores the divided data in the storage unit 16 for each rotor blade 2. By dividing the measurement data in this manner and associating the divided measurement data with each of the rotor blades 2 that pass through the measurement range of the sensor 11 as the rotor 1 rotates in the order in which the measurement data was obtained, it is possible to accumulate evaluation data of the clearance α for each rotor blade 2. For example, if X rotor blades 2 are provided on the outer periphery of the rotor 1, the measurement data for the 1st, X+1th, 2X+1th, ... are all measurement data of the clearance related to the same rotor blade 2. By dividing the measurement data measured while the rotor 1 is rotating and accumulating evaluation data for each rotor blade 2, it is possible to evaluate the clearance α of one rotor blade 2 based on a large number of measurement data.

[0023] The first threshold is set to an appropriate value between 1% and 50%. Since the light intensity changes depending on the state of the rotor blade 2 (operating time and deterioration), the first threshold is set appropriately depending on the state of the rotor blade 2 and the level of noise that is tolerable. An appropriate value between 0.05 and less than 1 second is set for the trigger holding time 54. This value is set appropriately depending on the rotation speed of the rotor 1, the number of moving blades 2 constituting one stage, the size of the moving blades 2, the distance between adjacent moving blades 2, etc. In addition, the sampling period of the sensor 11 is set to an appropriate value so that as much measurement data as possible can be collected.

[0024] The above describes a data division method that can be applied to situations where the rotation speed of rotor 1 is not constant, such as when rotor 1 is rotated by hand. However, when the rotation speed is known to be constant (the number of blades 2 is also known), such as when rotor 1 is rotated automatically, the measurement data can be divided for each blade 2 not only by the above method, but also by dividing the measurement data at equal intervals in time.

[0025] (Removal of spike noise) The clearance for each rotor blade 2 can be estimated from the measurement data divided for each rotor blade 2, but noise becomes a problem in this case. When measuring by irradiating light onto a dynamic object such as a rotating body, spike-like noise (referred to as spike noise) may be measured. The noise removal unit 14 removes the spike noise from the measurement data divided by the division unit 13. FIG. 6 shows an example of the measurement data after division. The vertical axis of the graph in FIG. 6 is distance or light intensity, and the horizontal axis is time. Graph 61 shows the transition of distance, and graph 62 shows the transition of light intensity. For example, the distance value shown in box 64 is spike noise. Spike noise is likely to occur when passing through a discontinuous part such as a scratch on the object or a corner (edge) of the blade, and is caused by a momentary disturbance of the reflected signal. In the case of a compressor, the spike noise is measured, for example, when the rotor blade 2 enters the measurement range or immediately after passing through. Furthermore, it is known that in rotor blades of compressors and the like, the occurrence of spike noise correlates with a decrease in light intensity, and the light intensity decreases when spike noise is measured. Using this property, the noise removal unit 14 regards the measurement data of the distance measured when the light intensity included in the measurement data falls below a predetermined threshold 63 (sometimes referred to as a second threshold) as spike noise, and excludes it from the evaluation target. For example, the noise removal unit 14 deletes the measurement data of the distance that is regarded as spike noise based on the light intensity from the measurement data for each rotor blade 2 stored in the memory unit 16.

[0026] (Clearance measurement) The clearance measurement unit 15 statistically processes the measurement data after the spike noise has been removed, and calculates the clearance α for each rotor blade 2. For example, the clearance measurement unit 15 calculates a frequency distribution for each rotor blade 2 from the distance measurement data after the spike noise has been removed. FIG. 7 shows an example of a frequency distribution calculated from the distance measurement data for one rotor blade 2. The vertical axis of the frequency distribution diagram (histogram) in FIG. 7 is frequency (frequency of occurrence of distance measurement values), and the horizontal axis is distance (clearance). For example, the clearance measurement unit 15 calculates a histogram as shown in FIG. 7 for each rotor blade 2, and calculates the most frequent value as the clearance α for that rotor blade 2. Alternatively, a predetermined number of clearances may be selected in descending order of frequency, and their average or weighted average (e.g., weighted by frequency) may be calculated as the clearance for the rotor blade 2 to be evaluated. Moreover, the clearance measurement unit 15 may assume that the frequency distribution of the clearance follows a normal distribution, calculate a normal distribution that approximates the clearance histogram, and calculate the average value (expected value) as the clearance α of the rotor blade 2 to be evaluated. Alternatively, the clearance frequency distribution may be assumed to follow a normal distribution, obtain a standard deviation σ, and calculate the minimum value as the clearance α from a range (e.g., a predetermined interval such as a 68% confidence interval for ±1σ, a 95% confidence interval for ±2σ, and a 99.7% confidence interval for ±3σ) that excludes values ​​outside the average value ±iσ (e.g., i=1, 2, 3, etc.; i is not limited to an integer).

[0027] (operation) Next, the operation of the measuring device 10 will be described with reference to FIG. FIG. 8 is a flowchart showing an example of the clearance measurement process according to the embodiment. For example, when assembling the rotating machine 100, during a trial run, or during regular inspection, the sensor 11 is installed at a predetermined position of the casing 3 without opening the casing 3. In addition, when measuring the distance and light intensity while rotating the rotor 1 at a low speed, a sampling period of the sensor 11 is set according to the rotation speed of the rotor 1, the size of the rotor 2, and the like, so that a sufficient number of measurement values ​​can be obtained for one moving blade 2. Next, the sensor 11 measures the distance and light intensity while rotating the rotor 1 at a low speed (step S1). The sensor 11 measures the distance and light intensity at a predetermined sampling period, and outputs the measurement results to the measurement device 10. The measurement data acquisition unit 12 acquires the time-series measurement data (measurement data of distance and measurement data of light intensity) measured by the sensor 11, and stores the data in the memory unit 16 (step S2).

[0028] When the collection of the measurement data is completed, the division unit 13 then reads out the measurement data stored in the storage unit 16 and divides the measurement data for each rotor blade 2 (step S3). As described with reference to Fig. 5, the division unit 13 divides the measurement data using a first threshold value (threshold value 53 in Fig. 5) and a trigger holding time 54, and stores the divided measurement data in the storage unit 16 in association with the rotor blade 2. For example, a mark may be attached to the rotor blade 2 that first passes through the measurement range of the sensor 11, and the measurement data measured first is associated with the marked rotor blade, and then, according to the rotation direction of the rotor 1, the rotor blade 2 that next passes through the measurement range of the sensor 11 is associated with the measurement data measured second, and the rotor blade 2 that passes through the measurement range third is associated with the measurement data measured third, etc.

[0029] Next, the noise removal unit 14 removes spike noise (step S4). For example, the noise removal unit 14 reads out the measurement data for each divided rotor blade 2 stored in the storage unit 16, and performs a process of deleting the measurement data of the distance measured when the light intensity is smaller than the second threshold (threshold 63 in FIG. 6) from each measurement data. Next, the clearance measurement unit 15 performs statistical processing to calculate the clearance (step S5). For example, the clearance measurement unit 15 calculates a moving average of the measurement data of the distance for each rotor blade 2 after noise removal, and calculates the distance (clearance) value of a predetermined number of points for each rotor blade 2. The clearance measurement unit 15 calculates a histogram of the calculated clearance values ​​of the predetermined number of points, and obtains the mode. The clearance measurement unit 15 calculates the mode for each rotor blade 2, and sets the value as the clearance measurement value of the rotor blade 2. The clearance measurement unit 15 stores the calculated clearance measurement value for each rotor blade 2 in the storage unit 16. Next, the clearance measurement unit 15 outputs the calculated clearance measurement value for each rotor blade 2 to a display device, an electronic file, or the like (step S6).

[0030] (effect) As described above, according to this embodiment, it is possible to measure the clearance between the tip of a rotating body, such as a rotor blade in a rotary machine, and a casing that houses the rotating body in a non-contact manner with high accuracy.

[0031] FIG. 9 is a diagram illustrating an example of a hardware configuration of the measurement apparatus according to the embodiment. The computer 900 includes a CPU 901, a main memory device 902, an auxiliary memory device 903, an input / output interface 904, and a communication interface 905. The above-mentioned measuring device 10 is implemented in the computer 900. The above-mentioned functions are stored in the auxiliary memory device 903 in the form of a program. The CPU 901 reads the program from the auxiliary memory device 903, loads it in the main memory device 902, and executes the above-mentioned processing in accordance with the program. The CPU 901 also secures a storage area in the main memory device 902 in accordance with the program. The CPU 901 also secures a storage area in the auxiliary memory device 903 for storing data being processed in accordance with the program.

[0032] A program for realizing all or part of the functions of the measuring device 10 may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read into a computer system and executed to perform processing by each functional unit. The term "computer system" as used herein includes hardware such as an OS and peripheral devices. In addition, if a WWW system is used, the term "computer system" also includes a homepage providing environment (or display environment). In addition, the term "computer-readable recording medium" refers to a portable medium such as a CD, DVD, or USB, or a storage device such as a hard disk built into a computer system. In addition, if the program is distributed to the computer 900 via a communication line, the computer 900 that receives the program may deploy the program in the main storage device 902 and execute the above processing. In addition, the above program may be for realizing part of the above-mentioned functions, or may be capable of realizing the above-mentioned functions in combination with a program already recorded in the computer system.

[0033] As described above, several embodiments according to the present disclosure have been described, but all of these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents as described in the claims, as well as in the scope and gist of the invention.

[0034] <Additional Notes> The measurement apparatus, the measurement method, and the program described in each embodiment can be understood, for example, as follows.

[0035] (1) A measuring device 10 according to a first aspect is a measuring device that measures a clearance between a rotating body in a rotating machine and a casing surrounding the rotating body, and includes: means for acquiring measurement data of the intensity of reflected light of light irradiated from the casing to the rotating body while rotating, and measurement data of the distance between the casing and the rotating body based on the reflected light; means for removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light; and means for statistically processing a plurality of the distance measurement data after noise removal to calculate a measurement value of the clearance. This makes it possible to measure the clearance between a rotating body in a rotating machine and a casing that houses the rotating body in a non-contact manner with high accuracy.

[0036] (2) A measuring device 10 according to a second aspect is the measuring device 10 of (1), wherein the noise removing means removes the measurement data of the distance based on the reflected light where the intensity of the reflected light is less than a predetermined first threshold value. This makes it possible to remove spike noise that is measured when a dynamic object is irradiated with light.

[0037] (3) A measuring device 10 according to a third aspect is the measuring device 10 of (1) to (2), wherein the rotating body is a rotor supported for free rotation and a plurality of moving blades arranged circumferentially on the outer periphery of the rotor, and further includes a means for dividing the acquired measurement data of the intensity of the reflected light and the measurement data of the distance for each moving blade based on the measurement data of the intensity of the reflected light. This makes it possible to measure the clearance between the tip of a rotor, such as a rotor blade in a rotary machine, and the casing for each rotor blade in a non-contact manner with high accuracy.

[0038] (4) A measuring device 10 according to a fourth aspect is the measuring device 10 of (3), wherein the acquiring means acquires time-series measurement data of the intensity of the reflected light and time-series measurement data of the distance measured during rotation of the rotating body, and the dividing means divides the measurement data of the intensity of the reflected light and the measurement data of the distance for each of the moving blades by extracting the measurement data of the intensity of the reflected light and the measurement data of the distance measured between the start point and the end point as measurement data of one of the moving blades, based on the time-series measurement data of the intensity of the reflected light, with a start point being a point at which the intensity becomes equal to or greater than a predetermined second threshold and an end point being a point at which a predetermined retention time has elapsed since the intensity fell below the second threshold after the start point. This allows the measurement data to be divided for each blade.

[0039] (5) A measuring device 10 according to a fifth aspect is the measuring device 10 of (1) to (4), wherein the means for calculating the clearance measurement value calculates a histogram of the measurement data of the plurality of distances after noise removal, and calculates the most frequent distance as the clearance measurement value. In this way, by statistically processing a large number of clearance measurement values ​​(distance measurement data), noise, outliers, etc. can be removed and a highly accurate clearance measurement value can be calculated.

[0040] (6) A measuring device 10 according to a sixth aspect is the measuring device 10 of (1) to (4), wherein the means for calculating the clearance measurement value calculates a normal distribution approximating a frequency distribution of the measurement data of the multiple distances after noise removal, and calculates the minimum value of a predetermined interval in the normal distribution as the clearance measurement value. In this way, by statistically processing a large number of clearance measurement values ​​(distance measurement data), noise, outliers, etc. can be removed and a highly accurate clearance measurement value can be calculated.

[0041] (7) The measurement device 10 according to a seventh aspect is the measurement device 10 of (1) to (5), further comprising a means for measuring the intensity of the reflected light and a means for measuring the distance. This makes it possible to obtain measurement data of the reflected light intensity and distance.

[0042] (8) The measuring device 10 according to the eighth aspect is the measuring device 10 of (1) to (7), further comprising a confocal sensor, and the acquiring means acquires measurement data of the intensity of the reflected light measured by the confocal sensor and measurement data of the distance. This makes it possible to obtain measurement data of the reflected light intensity and distance.

[0043] (9) A measurement method according to a ninth aspect is a measurement method for measuring a clearance between a rotating body in a rotating machine and a casing surrounding the rotating body, comprising the steps of: acquiring measurement data of the intensity of reflected light of light irradiated from the casing to the rotating body while rotating, and measurement data of the distance between the casing and the rotating body based on the reflected light; removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light; and statistically processing a plurality of the distance measurement data after noise removal to calculate a measurement value of the clearance.

[0044] (10) A program according to a tenth aspect causes a computer to execute a measurement process for measuring a clearance between a rotating body in a rotating machine and a casing surrounding the rotating body, the measurement process including the steps of acquiring measurement data of the intensity of reflected light of light irradiated from the casing to the rotating body while rotating and measurement data of the distance between the casing and the rotating body based on the reflected light, removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light, and statistically processing a plurality of the distance measurement data after noise removal to calculate a measurement value of the clearance. [Explanation of symbols]

[0045] 1. Rotor 2, 2a, 2b, 2c...moving blades 3. Casing 31...Inner surface 4. Stator blade 10. Measurement equipment 11. Sensor 12 Measurement data acquisition section 13...Divided part 14 Noise removal section 15 Clearance measurement section 16...Storage section 100 Rotating machinery 110...Confocal sensor 111...Light source 112···Beam splitter 113···Lens 114...Components 115 Spectrometer 116a, 116b, 116c, 116d...light 200...Object 900...Computer 901···CPU 902...Main memory 903...Auxiliary storage device 904 Input / Output Interface 905 Communication Interface

Claims

1. A measuring device for measuring a clearance between a rotating body in a rotary machine and a casing surrounding the rotating body, comprising: a means for acquiring measurement data of an intensity of reflected light of light irradiated from the casing to the rotating body during rotation, and measurement data of a distance between the casing and the rotating body based on the reflected light; a means for removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light; a means for statistically processing the plurality of pieces of measurement data of the distances after noise removal and calculating a measurement value of the clearance; A measuring device comprising:

2. The noise removing means removes the distance measurement data based on the reflected light in which the intensity of the reflected light is smaller than a predetermined first threshold value. The measurement device according to claim 1 .

3. The rotating body includes a rotor supported for free rotation and a plurality of rotor blades provided on an outer periphery of the rotor along a circumferential direction, a means for dividing the acquired measurement data of the intensity of the reflected light and the measurement data of the distance for each of the rotor blades based on the measurement data of the intensity of the reflected light; The measurement device according to claim 1 or 2, further comprising:

4. the acquiring means acquires time-series measurement data of the intensity of the reflected light and time-series measurement data of the distance measured during rotation of the rotating body, the dividing means divides the measurement data of the intensity of the reflected light and the measurement data of the distance for each of the rotor blades by extracting the measurement data of the intensity of the reflected light and the measurement data of the distance measured between the start point and the end point as measurement data of one of the rotor blades, where the start point is a point in time when the intensity becomes equal to or greater than a predetermined second threshold and the end point is a point in time when a predetermined retention time has elapsed since the intensity fell below the second threshold after the start point, based on the measurement data of the intensity of the reflected light in time series. The measurement device according to claim 3.

5. the means for calculating the clearance measurement value calculates a histogram of the plurality of pieces of measurement data of the distances after noise has been removed, and calculates a mode of the distances as the clearance measurement value. The measuring device according to claim 1 or 2.

6. the means for calculating the clearance measurement value calculates a normal distribution approximating a frequency distribution of the plurality of distance measurement data after noise removal, and calculates a minimum value in a predetermined section in the normal distribution as the clearance measurement value. The measuring device according to claim 1 or 2.

7. A means for measuring the intensity of the reflected light; A means for measuring the distance; The measurement device according to claim 1 or 2, further comprising:

8. Further comprising a confocal sensor, the acquiring means acquires measurement data of the intensity of the reflected light measured by the confocal sensor and measurement data of the distance; The measuring device according to claim 1 or 2.

9. A method for measuring a clearance between a rotating body in a rotary machine and a casing surrounding the rotating body, comprising the steps of: acquiring measurement data of an intensity of reflected light of light irradiated from the casing to the rotating body during rotation, and measurement data of a distance between the casing and the rotating body based on the reflected light; removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light; a step of statistically processing the noise-removed measurement data of the plurality of distances to calculate a measurement value of the clearance; A measurement method having the above-mentioned features.

10. On the computer, A measurement process for measuring a clearance between a rotating body in a rotary machine and a casing surrounding the rotating body, comprising: acquiring measurement data of an intensity of reflected light of light irradiated from the casing to the rotating body during rotation, and measurement data of a distance between the casing and the rotating body based on the reflected light; removing spike-like noise from the acquired distance measurement data based on the measurement data of the intensity of the reflected light; a step of statistically processing the noise-removed measurement data of the plurality of distances to calculate a measurement value of the clearance; A program for executing a measurement process having the steps:

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