Blade operating parameter measuring device and measuring method

Abstract

The application provides a kind of blade operating parameter measuring device, including pulse trigger device.Pulse trigger device is aligned on the blade on the rotating impeller.Pulse trigger device forms a light cone, and the reflection triggered pulse signal is caused when the blade passes through the light cone.Pulse trigger device records the start and end time of pulse signal, and can calculate the tip clearance and tip speed in combination with system calibration constant.The application also provides a measuring method based on the measuring device.In the measurement, high-precision speed sensor or angle sensor is not required for assistance, and the structure is simple and easy to operate.The light is perpendicular to the tip, the exit light path has a small inclination angle, and the reflected light signal is large, so the measurement accuracy is very high.Even in the case of unstable working medium density or blade surface being contaminated, affecting the reflection performance of the blade, high measurement accuracy can still be obtained through automatic calibration during the measurement process.

Description

Technical Field

[0001] This invention belongs to the field of turbomachinery, and particularly relates to a device and method for measuring blade operating parameters. Background Technology

[0002] Blades are among the most critical working components of turbomachinery. During research and development and operation, reliable methods are needed to measure key blade operating parameters, such as vibration, tip clearance, and tip velocity. Without reliable measurement methods, researchers often struggle to accurately pinpoint the cause of malfunctions.

[0003] Existing technologies include various devices and methods for measuring blade operating parameters, but each has its own limitations, making it impossible to simultaneously measure these parameters in an integrated system. For example:

[0004] Eddy current or inductive methods: These are the most common measurement methods in this field. Eddy current or inductive sensors are mounted on the casing to measure tip clearance and obtain tip timing signals for blade vibration measurement. While eddy current and inductive sensors offer high resolution for tip clearance measurement, their bandwidth is relatively low, making accurate measurement of high-speed rotating blades difficult. Custom-designed eddy current sensors are also expensive. Furthermore, these sensors have low resolution in determining blade passage time, hindering accurate blade vibration measurement. Finally, they cannot be used to measure tip velocity.

[0005] The tilted fiber bundle method involves mounting fiber optic sensors on the casing. When a blade passes the sensor, a pulse signal is generated, and the timing of this pulse is measured. On one hand, by measuring the time difference between the blade's arrival at the two tilted fiber bundles, the tip clearance can be calculated based on geometric relationships. On the other hand, the blade tip vibration displacement can also be calculated. However, this method requires ultra-high precision speed sensors, angular displacement sensors, or angle sensors to calculate the tip clearance, which is generally difficult to implement. Typical speed sensors can only achieve low-precision measurements. They can only measure tip clearance and blade vibration, not tip velocity.

[0006] Three-beam method: This method uses a high-precision fiber optic probe that emits three laser beams. The main difference from the tilted fiber beam method is the addition of a parallel outgoing optical path. This method can obtain the instantaneous rotational speed of the blade. However, it uses a specially designed probe, which is difficult to manufacture and therefore expensive. Furthermore, this method has only been used in a few laboratory settings, and its reliability is not guaranteed. Due to the large tilt angle of the outgoing optical path and the small reflected light signal, the measurement accuracy of the blade arrival time may be low.

[0007] Reflected light intensity method: An optical fiber sensor is mounted on the casing. The tip clearance is obtained by analyzing the magnitude of the reflected light intensity. To eliminate the influence of systematic errors such as optical path loss and changes in tip reflectivity, two photoelectric probes are needed to measure the voltage quotient. However, this method relies entirely on tip reflection for measurement, requiring precise calibration, which is difficult to achieve. If the working fluid density is unstable or the blade surface is contaminated, affecting the blade's reflectivity, the measurement value will be distorted, resulting in poor measurement reliability. Furthermore, tip velocity cannot be measured.

[0008] Laser Doppler method: An optical observation window is opened on the housing. A laser Doppler velocimeter is mounted outside the window to directly measure the velocity of the internal blades. However, this method can only be used to measure blade tip velocities. The equipment is expensive, bulky, and complex to install, requiring a light-transmitting window on the housing, making it suitable only for scientific research and not for industrial applications.

[0009] It can be seen that the existing measurement methods cannot simultaneously measure the gap between the blade tip clearance and the blade tip velocity; or they rely on high-precision components, which are difficult to achieve; or their accuracy decreases when the blade tip is contaminated and its reflective properties change, making them unsuitable for measurement work.

[0010] Therefore, those skilled in the art expect to develop a blade operating parameter measuring device and its corresponding measuring method to solve the technical problems existing in the prior art. Summary of the Invention

[0011] One object of this application is to provide a blade operating parameter measuring device, including a pulse triggering device, wherein the device includes two pulse triggering devices that are detachably arranged in parallel.

[0012] Preferably, the pulse triggering device is configured to acquire the pulse signal generation time and the pulse signal disappearance time.

[0013] Preferably, the pulse triggering device includes a light source component and a probe, wherein the light emitted by the light source component passes through the probe to form a light cone.

[0014] Preferably, the light cone exits from the probe, is incident perpendicularly on the blade tip, and is reflected back to the probe by the blade tip.

[0015] Preferably, the probe is connected to the light source component via a bundled optical fiber. The light source component includes a laser, and the bundled optical fiber includes an incident end. The laser emitted by the laser reaches the probe through the incident end.

[0016] Preferably, the bundled optical fiber includes a receiving end, and the light cone, after being reflected by the leaf tip, reaches the receiving end through the probe.

[0017] Preferably, the probe includes a focusing component, and the light emitted by the light source component passes through the focusing component to form the light cone.

[0018] Preferably, the pulse triggering device includes a timing device connected to the light source component, and the timing device is configured to record the time of light emission and arrival.

[0019] Preferably, the device further includes a data processing unit electrically connected to the timing device, the data processing unit being configured to process and display data.

[0020] Preferably, it further includes a key phase sensor, which is electrically connected to the timing device.

[0021] Another objective of this application is to provide a method for measuring blade operating parameters, employing the aforementioned blade operating parameter measuring device, specifically including the following steps:

[0022] Step 1: Set the first pulse triggering device and the second pulse triggering device in parallel and align them with the blades on the rotating impeller;

[0023] Step 2: When the blade passes the first pulse triggering device, record the first pulse generation time t. arrv,1 The first pulse disappearance time t leav，1 The triggering period t of the first blade was calculated. trig，1 =t leav，1 -t arrv，1 ;

[0024] Step 3: When the blade passes the second pulse triggering device, record the second pulse generation time t. arrv，2 The disappearance time t of the second pulse leav，2 The triggering period t of the second blade was calculated. trig，2 =t arrv，2 -tl eav，2 ;

[0025] Step 4: Use the first blade triggering period t trig，1 The second blade triggering period t trig，2 And by combining the system calibration constants, the tip clearance c is calculated;

[0026] Step 5: Use the first blade triggering period t trig，1 The second blade triggering period t trig，2 By combining the system calibration constant, the tip velocity v is calculated.

[0027] Preferably, the tip clearance c in step four and the tip velocity v in step five conform to the following relationship:

[0028] c = k1vt trig，1 +b1=k2vt trig，2 +b2

[0029] Wherein, k1, k2, b1 and b2 are all system calibration constants, obtained through calibration.

[0030] Preferably, the step four, which involves calculating the blade tip clearance c, includes:

[0031] Let κ = k1 / k2, τ = t trig，2 / t trig，1 Δb=b1-b2;

[0032] Solving for:

[0033] Preferably, the tip velocity v calculation step in step five includes:

[0034] Let κ = k1 / k2, τ = t trig，2 / t trig，1 Δb=b1-b2;

[0035] Solving for:

[0036] Another objective of this application is to provide a method for measuring blade operating parameters, employing the aforementioned blade operating parameter measuring device, specifically including the following steps:

[0037] Step 1: Set the first pulse triggering device and the second pulse triggering device in parallel, align them with the blades on the rotating impeller, and align the key phase sensor with the key phase position of the impeller shaft.

[0038] Step 2: Calibrate the system to obtain calibration constants;

[0039] Step 3: When the blade passes the first pulse triggering device, record the first pulse generation time t. arrv，1 The first pulse disappearance time t leav，1 The triggering period t of the first blade was calculated. trig，1 =t leav，1 -t arrv，1 ;

[0040] Step 4: When the blade passes the second pulse triggering device, record the second pulse generation time t. arrv，2 The disappearance time t of the second pulse leav，2 The triggering period t of the second blade was calculated.trig，2 =t arrv，2 -t leav，2 ;

[0041] Step 5: After the impeller rotates one revolution, construct the observation matrix C;

[0042] Step 6: Construct the measurement vector y;

[0043] Step 7: Construct a Kalman filter to predict the one-step estimate of the state vector and the uncertainty matrix value, and correct and update the one-step estimate of the state vector and the uncertainty matrix value as the impeller rotates;

[0044] Step 8: Repeat step 7 until the impeller stops rotating;

[0045] Step 9: After the impeller stops rotating, calculate the tip clearance c and tip velocity v based on the calibration constant and the value of the state vector.

[0046] Preferably, the calibration constants in step two are k1, k2, b1, and b2, and τ = t trig，2 / t trig，1 .

[0047] Preferably, the observation matrix C mentioned in step five is specifically:

[0048]

[0049] Wherein, the superscripts i and n represent the quantities measured by the i-th leaf in the nth revolution, r is the leaf tip radius, and m is the number of leaves.

[0050] Preferably, the measurement vector y in step six is ​​specifically:

[0051]

[0052] in, The average rotational speed is measured by the key phase sensor.

[0053] Preferably, step seven specifically includes:

[0054] Step 1, Initialization: Provide a one-step estimate of the state vector. And the initial values ​​of the uncertainty matrix P(0,0);

[0055] Step 2: Predict the state vector and estimate the uncertainty matrix in one step.

[0056]

[0057] P(n+1, n) = P(n, n) + Q1(n)

[0058] Where n is the number of times the impeller rotates;

[0059] Step 3, Correction: Let n = n + 1. Calculate

[0060] G(n)=P(n,n-1)C T (n)[C(n)P(n,n-1)C T (n)+Q2(n)] -1

[0061]

[0062] Update the estimated value of the state vector in one step

[0063]

[0064] Update the estimate of the uncertainty matrix

[0065] P(n,n)=(IG(n)C(n))P(n,n-1).

[0066] Preferably, in step nine, the tip clearance c is calculated using the following formula:

[0067]

[0068] The blade tip velocity v is calculated using the following formula:

[0069]

[0070] Compared with the prior art, the blade operating parameter measuring device and method provided in this application have at least the following beneficial technical effects:

[0071] 1. The technical solution of this application measures the generation time and disappearance time of the pulse triggered when the blade passes by using two pulse triggering devices. Then, the blade tip gap and blade tip speed are calculated, so that the two blade operating parameters can be measured simultaneously.

[0072] 2. The technical solution of this application does not require high-precision speed sensor, angular displacement sensor or angle sensor for measurement, and has a simple structure and is easy to operate.

[0073] 3. The technical solution of this application has a light source that is perpendicular to the leaf tip, a small tilt angle of the outgoing light path, and a large reflected light signal, thus resulting in high measurement accuracy.

[0074] 4. The technical solution of this application, in conjunction with the key phase sensor, can still achieve high measurement accuracy through automatic calibration during the measurement process, even when the working fluid density is unstable or the blade surface is contaminated, affecting the blade's reflectivity. Attached Figure Description

[0075] Figure 1 This is a schematic diagram of the overall structure of one embodiment of this application;

[0076] Figure 2 This is a schematic diagram of the probe portion structure according to an embodiment of this application;

[0077] Figure 3 This is a comparison chart of measurement results using an embodiment of this application and measurement results using prior art;

[0078] Figure 4 This is a comparison chart of measurement results using an embodiment of this application and measurement results using existing technologies.

[0079] Among them, 1-probe, 11-protective lens, 12-protective lens, 13-base, 14-convex lens, 15-convex lens, 16-convex lens mounting base, 17-convex lens mounting base, 2-light source component, 21-bundled fiber, 22-bundled fiber, 31-incident end, 32-incident end, 41-receiver end, 42-receiver end, 5-blade tip timing system, 6-host computer, 71-light cone, 72-light cone, 8-casing, 9-blade, 10-impeller, 111-key phase sensor. Detailed Implementation

[0080] The embodiments of the present invention are described below with reference to the accompanying drawings to make the technical content clearer and easier to understand. The present invention can be embodied in many different forms, and the scope of protection of the present invention is not limited to the embodiments mentioned herein.

[0081] Example 1

[0082] This embodiment is a blade operating parameter measuring device, including a pulse triggering device. The pulse triggering device forms a light cone and illuminates the rotating blade. When the blade passes the pulse triggering device, a pulse signal is triggered. The pulse triggering device measures the generation and termination times of the pulse signal, and calculates the blade operating parameters by combining these times with system calibration constants.

[0083] In this embodiment, specifically as follows: Figure 1 As shown, the device includes two pulse triggering devices, each comprising a probe 1. The two pulse triggering devices are arranged in parallel and separable configurations. In this embodiment, the probe 1 is mounted on a housing 8. The housing 8 has two through holes aligned with the blades 9 on the impeller 10. The probe 1 forms two light cones 71 and 72, which are aligned with the blades 9 on the impeller 10 through the two through holes on the housing 8. Specifically, this alignment refers to the light cones being incident perpendicularly on the tip of the blade 9, so that the light cones 71 and 72 incident on the blade tip, after reflection from the blade tip, return to the probe 1 along the same path.

[0084] The probe 1 is connected to the light source component 2 via bundled optical fibers 21 and 22. The light source component 2 is preferably a laser; however, in other similar embodiments, it can be other light-emitting components. Specifically, the bundled optical fiber 21 has an incident end 31 and a receiving end 41, and the bundled optical fiber 22 has an incident end 32 and a receiving end 42. The incident ends 31 and 32 are connected to the light source. The laser light is emitted from the light source, enters the bundled optical fibers 21 and 22 through the incident ends 31 and 32, and then generates light cones 71 and 72 through the probe 1. The receiving ends 41 and 42 are connected to a timing device. This timing device records the time of laser emission and reception. In this embodiment, the timing device is preferably a leaf tip timing system 5. When the blade 9 passes through the light cones 71 and 72 sequentially, the reflected light cones reach the leaf tip timing system 5 through the probe 1, bundled optical fibers 21 and 22, and receiving ends 41 and 42, triggering two secondary pulse signals. The generation time of the first pulse signal is denoted as t. arrv，1 The disappearance time is denoted as t. leav，1 The generation time of the second pulse signal is denoted as t. arrv，2 The disappearance time is denoted as t. leav，2 Define the blade triggering period t. trig，1 and t trig，2 :t trig，1 =t leav，1 -t arrv，1 , t trig，2 =t arrv，2 -t leav，2 The leaf tip timing system 5 is electrically connected to the data processing device for transmitting signals and data. In this embodiment, the data processing device is preferably a host computer 6. The host computer 6 is configured to process and display data.

[0085] like Figure 2The diagram shows the structure and installation of probe 1 in this embodiment. It includes a base 13, which is generally cuboid in shape. Two parallel through holes are provided inside the base 13, and two focusing components are arranged parallel to each other within these through holes. The base 13 can be integral or partially separate, allowing the two pulse triggering devices with focusing components to be arranged detachably in parallel. In other similar embodiments, the base 13 may not be used, as long as the two pulse triggering devices can be arranged detachably in parallel. In this embodiment, the through holes are preferably cylindrical. The focusing components are specifically convex lenses 14 and 15. In other similar embodiments, the focusing components can also be lens groups capable of forming light cones, etc. The convex lenses 14 and 15 are preferably cylindrical, their dimensions matching the through holes inside the base 13. They are inserted into the base 13 from one end and fixed inside. The two through holes are arranged parallel, allowing the two convex lenses to be placed parallel to each other. Convex lens 14 is connected to light source component 2 via convex lens mounting base 17, and convex lens 15 is connected to light source component 2 via convex lens mounting base 16. Specifically, they are connected to light source component 2 via bundled optical fibers 21 and 22. Protective lenses 11 and 12 are also provided at the end of base 13 near impeller 10 for dust prevention and protection of the convex lenses.

[0086] The method for measuring blade operating parameters using the measuring device described in this embodiment includes:

[0087] Step 1: Set the two pulse triggering devices containing probe 1 in parallel and align them with the blades 9 on the rotating impeller 10;

[0088] Step 2: When the blade 9 passes the first pulse triggering device, record the time t when the first pulse is generated. arrv，1 The first pulse disappearance time t leav，1 The triggering period t of the first blade was calculated. trig，1 =t leav，1 -t arrv，1 ;

[0089] Step 3: When the blade 9 passes the second pulse triggering device, record the second pulse generation time t. arrv，2 The disappearance time t of the second pulse leav，2 The triggering period t of the second blade was calculated. trig，2 =t arrv，2 -t leav，2 ;

[0090] Step 4: Use the first blade triggering period t trig，1 The second blade triggering period t trig，2 And by combining the system calibration constant, the tip clearance c is calculated.

[0091] Step 5: Use the first blade triggering period ttrig，1 The second blade triggering period t trig，2 By combining the system calibration constant, the tip velocity v is calculated.

[0092] In this embodiment, the tip clearance c in step four and the tip velocity v in step five conform to the following relationship:

[0093] c = k1vt trig，1 +b1=k2vt trig，2 +b2

[0094] Wherein, k1, k2, b1, and b2 are all system calibration constants, obtained through calibration. Specifically, k1 and k2 represent the negative apex angles of the regions where a pulse can be triggered when the blade passes through light cones 71 and 72, respectively; b1 and b2 represent the distance between the blade and the pulse triggering device when the blade is far away from the device and just does not trigger. This distance is only an abstract theoretical value and needs to be determined by extrapolation in actual calibration.

[0095] Let κ = k1 / k2, τ = t trig，2 / t trig，1 Δb=b1-b2;

[0096] Through formula Calculate the tip clearance; calculate using the formula. Leaf tip speed.

[0097] like Figure 3 The figure shows a comparison between the measurement results obtained using the measuring device of this embodiment and the blade tip clearance data obtained using the traditional eddy current sensor method. The six sub-figures from top to bottom show the measurement results of the six blades in the experiment. The horizontal axis represents the number of impeller rotations, and the vertical axis represents the measured blade tip clearance. In the experiment, the blade tip clearance was adjusted approximately every 600 rotations and then stabilized for a period of time, for a total of six adjustments. Therefore, the measurement results show a step-like variation. Dark black and light gray represent the measurement values ​​of the dual-lens method described in this invention (i.e., this embodiment) and the traditional eddy current method, respectively. It can be seen that the changes are basically the same for both. The random error in measuring the blade tip clearance using the dual-lens measurement method in this embodiment does not exceed 30 micrometers.

[0098] This embodiment measures the blade triggering period using two pulse triggering devices and calculates the tip clearance c and tip velocity v using the system's calibration parameters, thus enabling simultaneous measurement of both. Furthermore, probe 1 has a simple structure, does not rely on high-precision sensors monitoring shaft angular velocity or angular position, and does not require a specialized probe for measurement, while maintaining high measurement accuracy.

[0099] Example 2

[0100] When the tip of blade 9 is contaminated, it causes a change in the tip's reflectivity, generally manifested as a decrease in reflected light intensity. Furthermore, under the same tip clearance conditions, compared to an uncontaminated blade, the trigger pulse period is shortened, meaning the system calibration parameters b1 and b2 decrease. Generally, Δb should be recalibrated before continuing to use the method of Embodiment 1 for measurement, but this is difficult to achieve in real-world scenarios and has low reliability; therefore, the design of this embodiment is adopted.

[0101] The structure of this embodiment is similar to that of Embodiment 1, except that a key phase sensor 111 is additionally provided. The key phase sensor 111 is aligned with the rotating impeller 10 and is used to measure the angular velocity of the impeller 10. At the same time, the key phase sensor 111 is electrically connected to the blade tip timing system 5 to transmit signals and data.

[0102] The method for measuring blade operating parameters using the measuring device described in this embodiment includes:

[0103] Step 1: Set the first pulse triggering device and the second pulse triggering device in parallel, and align the probe 1 of the first pulse triggering device and the second pulse triggering device and the key phase sensor 111 with the blade 9 on the rotating impeller 10.

[0104] Step 2: Calibrate the system to obtain calibration constants k1, k2, b1, and b2;

[0105] Step 3: When the blade passes the first pulse triggering device, record the first pulse generation time t. arrv，1 The first pulse disappearance time t leav，1 The triggering period t of the first blade was calculated. trig，1 =t leav，1 -t arrv，1 ;

[0106] Step 4: When the blade passes the second pulse triggering device, record the second pulse generation time t. arrv，2 The disappearance time t of the second pulse leav，2 The triggering period t of the second blade was calculated. trig，2 =t arrv，2 -t leav，2 ;

[0107] Step 5: Let the number of blades be m, the initial number of rotations n = 0, the blade tip radius be r, and τ = t trig，2 / t trig，1 After impeller 10 rotates one revolution, the observation matrix C is constructed:

[0108]

[0109] Wherein, the superscripts i and n represent the quantities measured by the i-th blade in the nth revolution;

[0110] Step 6: Construct the measurement vector y:

[0111]

[0112] in, The average rotational speed measured by the key phase sensor 111;

[0113] Step 7: Construct a Kalman filter to predict the one-step estimate of the state vector and the uncertainty matrix value, and as the impeller rotates, correct and update the one-step estimate of the state vector and the uncertainty matrix value, specifically as follows:

[0114] Give a one-step estimate of the state vector And the initial values ​​of the uncertainty matrix P(0,0);

[0115] As impeller 10 rotates from the nth revolution to the (n+1)th revolution:

[0116] One-step estimation of the predicted state vector and uncertainty matrix:

[0117]

[0118] P(n+1, n) = P(n, n) + Q1(n)

[0119] Let n = n + 1. Calculate...

[0120] G(n)=P(n,n-1)C T (n)[C(n)P(n,n-1)C T (n)+Q2(n)] -1

[0121]

[0122] Update the estimated value of the state vector in one step

[0123]

[0124] Update the estimate of the uncertainty matrix

[0125] P(n,n)=(IG(n)C(n))P(n,n-1);

[0126] Step 8: Before the impeller 10 stops rotating, repeat step 7.

[0127] Step 9: After the impeller 10 stops rotating, calculate the tip clearance c and tip velocity v based on the calibration constant and the value of the state vector.

[0128] The tip clearance c is calculated using the following formula:

[0129]

[0130] The blade tip velocity v is calculated using the following formula:

[0131]

[0132] Using the blade operating parameter measuring device described in this embodiment, the calibration constant can be dynamically calibrated and corrected during the rotation of the impeller 10. For example... Figure 4 As shown, in this embodiment, the dual-lens method with a key phase sensor is used to measure the tip clearance of a contaminated blade tip. Initially, the results differ significantly from those measured by the eddy current method due to the influence of light reflection. However, with increasing rotational revolutions, the calibration constant is automatically corrected. After more than 50 rotations, the measurement results approach those of the eddy current method. Similarly, this embodiment can simultaneously measure the tip clearance c and the tip velocity v. Furthermore, although a key phase sensor is added in this embodiment, the structure remains simple, does not rely on high-precision sensors monitoring shaft angular velocity or angular position, does not require a special probe, and exhibits high measurement accuracy.

[0133] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A method for measuring blade operating parameters, characterized in that, A blade operating parameter measuring device is used, the device including a pulse triggering device, wherein two pulse triggering devices are arranged in parallel and separable manner, specifically including the following steps: Step 1: Set the first pulse triggering device and the second pulse triggering device in parallel and align them with the blades on the rotating impeller; Step 2: When the blade passes the first pulse triggering device, record the time of the first pulse generation. First pulse disappearance time The triggering period of the first blade was calculated. ; Step 3: When the blade passes the second pulse triggering device, record the time of the second pulse generation. The disappearance time of the second pulse The triggering period of the second blade was calculated. ; Step 4: Use the first blade trigger cycle The second blade triggering cycle And by combining the system calibration constants, the tip clearance was calculated. c ; Step 5: Use the first blade trigger cycle The second blade triggering cycle And by combining the system calibration constants, the tip velocity was calculated. v ; The blade tip clearance c in step four and the blade tip velocity v in step five conform to the following relationship: in, , , and All of these are system calibration constants, obtained through calibration; Among them, the blade tip gap mentioned in step four c The calculation steps include: make , , ; Solving for: .

2. A method for measuring blade operating parameters, characterized in that, A blade operating parameter measuring device is used, the device including a pulse triggering device, wherein two pulse triggering devices are arranged in parallel and separable manner, specifically including the following steps: Step 1: Set the first pulse triggering device and the second pulse triggering device in parallel and align them with the blades on the rotating impeller; Step 2: When the blade passes the first pulse triggering device, record the time of the first pulse generation. First pulse disappearance time The triggering period of the first blade was calculated. ; Step 3: When the blade passes the second pulse triggering device, record the time of the second pulse generation. The disappearance time of the second pulse The triggering period of the second blade was calculated. ; Step 4: Use the first blade trigger cycle The second blade triggering cycle And by combining the system calibration constants, the tip clearance was calculated. c ; Step 5: Use the first blade trigger cycle The second blade triggering cycle And by combining the system calibration constants, the tip velocity was calculated. v ; The blade tip clearance c in step four and the blade tip velocity v in step five conform to the following relationship: in, , , and All of these are system calibration constants, obtained through calibration; Among them, the blade tip velocity mentioned in step five v The calculation steps include: make , , ; Solving for: .

3. A method for measuring blade operating parameters, characterized in that, A blade operating parameter measuring device is employed, comprising a pulse triggering device, wherein two pulse triggering devices are arranged in parallel and separable configuration; wherein the pulse triggering device is configured to acquire the pulse signal generation time and pulse signal disappearance time; wherein the pulse triggering device includes a light source component and a probe, the light emitted by the light source component passing through the probe to form a light cone; wherein the pulse triggering device includes a timing device connected to the light source component, the timing device being configured to record the light emission and arrival times; wherein it further includes a data processing device electrically connected to the timing device, the data processing device being configured to process and display data; wherein it further includes a key phase sensor electrically connected to the timing device; specifically including the following steps: Step 1: Set the first pulse triggering device and the second pulse triggering device in parallel, align the first pulse triggering device and the second pulse triggering device with the blades on the rotating impeller, and align the key phase sensor with the key phase position of the impeller shaft; Step 2: Calibrate the system to obtain calibration constants; Step 3: When the blade passes the first pulse triggering device, record the time of the first pulse generation. First pulse disappearance time The triggering period of the first blade was calculated. ; Step 4: When the blade passes the second pulse triggering device, record the time of the second pulse generation. The disappearance time of the second pulse The triggering period of the second blade was calculated. ; Step 5: After the impeller rotates one revolution, construct the observation matrix C; Step 6: Construct the measurement vector y; Step 7: Construct a Kalman filter to predict the one-step estimate of the state vector and the uncertainty matrix value, and correct and update the one-step estimate of the state vector and the uncertainty matrix value as the impeller rotates; Step 8: Repeat step 7 until the impeller stops rotating; Step 9: After the impeller stops rotating, calculate the tip clearance based on the values ​​of the calibration constant and the state vector. c and tip speed v .

4. The blade operating parameter measurement method as described in claim 3, wherein, The calibration constant mentioned in step two is , , and and order .

5. The blade operating parameter measurement method as described in claim 4, wherein, The observation matrix C mentioned in step five is specifically as follows: Among them, superscript Indicates the first The quantities measured by each blade in the nth revolution, where r is the blade tip radius and m is the number of blades.

6. The blade operating parameter measurement method as described in claim 5, wherein, The measurement vector y mentioned in step six is ​​specifically: in, The average rotational speed is measured by the key phase sensor.

7. The blade operating parameter measurement method as described in claim 6, wherein, Step seven specifically includes: Step 1, Initialization: Provide a one-step estimate of the state vector. and uncertainty matrix The initial value; Step 2: Predict the state vector and estimate the uncertainty matrix in one step. ； Where n is the number of times the impeller rotates; Step 3, Correction: Let ,calculate Update the estimated value of the state vector in one step Update the estimate of the uncertainty matrix 。 8. The blade operating parameter measurement method as described in claim 7, wherein, In step nine, the blade tip clearance is calculated. c Using the following formula: Calculate the tip velocity v Using the following formula: 。

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