Rotor blade full frequency vibration blade tip timing measurement method and system

Abstract

Disclosed are a method and system for measuring the full-frequency vibration tip timing of a rotor blade. The method includes: identifying the low-frequency, medium-frequency, high-frequency and ultra-high-frequency modal parameters of the rotor blade, determining the number and installation angle of sensors; realizing the identification of the low-frequency vibration parameters of the tip timing based on the tip vibration displacement; realizing the identification of the medium-frequency vibration parameters of the tip timing based on the tip vibration velocity; realizing the identification of the high-frequency vibration parameters of the tip timing based on the tip acceleration; and realizing the identification of the ultra-high frequency vibration parameters of the tip timing based on the tip acceleration, and finally realizing the low-frequency, medium-frequency, high-frequency and ultra-high-frequency full-frequency vibration tip timing measurement of the rotor blade. The present invention also discloses a system based on the full-frequency vibration parameter identification method of the tip timing. The present invention discloses a method for measuring the full-frequency vibration of the tip timing, realizing the identification of the low-frequency, medium-frequency, high-frequency and ultra-high-frequency vibration parameters of the rotor blade, and expanding the blade vibration frequency range that can be effectively measured by the tip timing technology.

Description

Technical Field

[0001] The present invention relates to the technical field of non-contact measurement of rotor blades of rotating machinery, and in particular to a method and system for timing measurement of full-frequency-domain vibration blade tips of rotor blades. Background Art

[0002] Blade tip timing (BTT) is a non-contact measurement technology that is widely used in the measurement and monitoring of blade vibration of turbine machinery. This technology installs timing sensors on the circumference of the casing, compares the measured actual arrival time of the blade with the theoretical arrival time of the blade in the absence of vibration, and combines the rotor speed to obtain the circumferential vibration displacement of all blades in the entire stage. However, although the traditional blade tip vibration displacement measurement method can obtain the blade vibration parameters of low-frequency one-bend vibration, it is still difficult to accurately measure the intermediate frequency, high frequency and ultra-high frequency of blade vibration. Usually, the dynamic frequency of fan blades is low. However, for compressors, especially high-pressure compressors, the first-order frequency is in several thousand hertz. Therefore, the measurement and monitoring of the intermediate frequency and ultra-high frequency of blade vibration becomes particularly important. According to the fact that blade vibration can be defined as different physical quantities such as displacement, velocity, acceleration or jerk, it has the characteristics of unchanged period and frequency. According to the signal characteristics of different physical quantities, the vibration signals of different frequency components can be enhanced. Therefore, the present invention provides a method and system for identifying blade tip timing vibration parameters in the full frequency domain by obtaining blade vibration responses of different measured physical quantities. It can provide more comprehensive blade vibration information and provide a more reliable basis for blade vibration analysis and fault diagnosis. This method is a further development and improvement of blade tip timing technology and has important application value in the operation, maintenance and fault warning of impeller machinery.

[0003] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a full-frequency domain blade tip timing vibration parameter identification method and system to solve the disadvantage that the traditional blade tip vibration displacement is difficult to accurately measure at the intermediate frequency, high frequency and ultra-high frequency of blade vibration, and to realize the blade tip timing full-frequency domain vibration measurement by using the blade tip vibration displacement, velocity, acceleration and jerk respectively.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A rotor blade full-frequency vibration blade tip timing measurement method of the present invention comprises:

[0007] In the first step S1, the rotor blades are subjected to prestress modal analysis and modal parameters of low frequencies with a vibration frequency less than 500 Hz, modal parameters of medium frequencies with a vibration frequency between 500 Hz and 2000 Hz, modal parameters of high frequencies with a vibration frequency between 2000 Hz and 5000 Hz, and modal parameters of ultra-high frequencies with a vibration frequency greater than 5000 Hz are obtained to determine the number and installation angle of blade tip timing sensors;

[0008] The second step S2 is to install the blade tip timing sensor circumferentially on the rotor blade casing, obtain the time sequence of the rotor blade reaching the blade tip timing sensor, and determine the reference speed based on the time sequence;

[0009] The third step S3 is to obtain the ideal arrival time of the blade based on the low-frequency vibration parameter less than 500 Hz according to the reference speed and the installation angle of the sensor. Combined with the actual arrival time t of the rotor blade passing the blade tip timing sensor i，b，n Get the time difference Δt i，b，n ,in, Based on the measured rotation radius R from the rotor blade tip rotation axis to the blade tip BTT and time difference Δt i，b，n The blade tip vibration displacement is obtained, based on the vibration parameters of the medium frequency of 500 Hz-2000 Hz, the blade tip vibration velocity is obtained according to the relationship between the measured actual blade arrival time and the angles of the adjacent installed sensors, based on the vibration parameters of the high frequency of 2000 Hz-5000 Hz, the blade tip vibration acceleration is obtained according to the installation angles of three adjacent blade tip timing sensors and the measured actual blade arrival time, based on the vibration parameters of the ultra-high frequency with a vibration frequency greater than 5000 Hz, the blade tip vibration acceleration is obtained according to the installation angles of four adjacent blade tip timing sensors and the measured actual blade arrival time, wherein the vibration parameters include frequency, amplitude and phase;

[0010] The fourth step S4 is to obtain the vibration frequency, amplitude and phase of the rotor blades at low frequency, medium frequency, high frequency and ultra-high frequency using the obtained blade tip vibration displacement, blade tip vibration velocity, blade tip vibration acceleration and blade tip vibration jerk of different blade tips.

[0011] In the method, in the first step S1, a prestressed modal analysis is performed on the rotor blade to obtain a low-frequency modal f of the rotor blade with a vibration frequency less than 500 Hz under a given working condition. L 、Intermediate frequency mode f within 500Hz-2000Hz M , high frequency mode f within 2000Hz-5000Hz H and ultra-high frequency modes f with frequencies greater than 5000Hz S According to the low frequency mode fL , intermediate frequency mode f M , high frequency mode f H and the ultra-high frequency mode f s The number of frequency components m determines the number of blade tip timing sensors N p , where N p ≥2m+1.

[0012] In the method, in the first step S1, according to the low-frequency mode f L , intermediate frequency mode f M , high frequency mode f H and the ultra-high frequency mode f s The frequency components of the blade tip timing sensor circumferential installation angle measurement matrix Θ are constructed, wherein the expression of the angle measurement matrix Θ is:

[0013]

[0014] in, For N p The installation angle between the blade tip timing sensor and the speed sensor is determined according to the condition number of the angle measurement matrix, and the circumferential layout of the blade tip timing sensor is determined, cond(Θ)=||Θ||·||Θ -1 ||.

[0015] In the method, in the second step S2, an OPR speed sensor is installed to measure the time series τ OPR，n , based on the time series τ OPR，n Calculate the reference speed f in the nth circle r ,in,

[0016] In the method described, in the second step S2, according to the N p N measured by the blade tip timing sensor b The actual arrival time of the leaf is t i，b，n , the reference speed f in the nth circle r for:

[0017] In the method described, the third step S3 comprises,

[0018] S301, based on the low-frequency vibration parameters less than 500 Hz, according to the measured rotation radius R from the rotor blade tip rotation axis to the blade tip BTT Obtain the vibration displacement d of the tip of blade No. b of blade tip timing sensor No. i in the nth circle i，b，n , where d i，b，n =2πR BTT At i，b，n , where the time difference

[0019] S302, based on the vibration parameters of the medium frequency of 500Hz-2000Hz, the vibration speed of the tip of the blade No. b in the nth circle is calculated using the adjacent double blade end timing sensors No. i and No. j=i+1 and the measured actual arrival time in, θ i ,θ j are the installation angles between the i-th and j-th blade tip timing sensors and the speed sensor, respectively, and the actual arrival time t of the i-th blade tip timing sensor i，b，n , the actual arrival time t of the jth blade tip timing sensor j，b，n S303, based on the high-frequency vibration parameters of 2000Hz-5000Hz, the vibration acceleration of the tip of the blade No. b in the nth circle is calculated using the three adjacent blade tip timing sensors No. i, No. j=i+1 and No. l=i+2 and the measured actual arrival time. in, Wherein, β represents the angular acceleration of the rotor; if the rotor speed is constant, based on the blade tip vibration acceleration, when the rotor speed is constant, the angular acceleration of the rotor β=0, and the blade tip vibration acceleration is expressed as: When the rotor speed is variable, based on the blade tip vibration acceleration, when the rotor speed is constant, the rotor angular acceleration β≠0, at this time the blade tip vibration acceleration is expressed as:

[0020] S304, based on the ultra-high frequency vibration parameters with a vibration frequency greater than 5000 Hz, the vibration acceleration of the tip of the blade No. b in the nth circle is calculated using the four adjacent blade tip timing sensors No. i, No. j=i+1, No. l=i+2 and No. q=i+3 and the measured actual arrival time sequence in,

[0021]

[0022] In the method, in the fourth step S4, the blade tip vibration measurement response Y is generated according to the blade tip vibration displacement, blade tip vibration velocity, blade tip vibration acceleration and blade tip vibration jerk, and the blade tip timing vibration parameters of different frequency bands are obtained by least square method.

[0023] In the method described, the blade tip timing vibration parameters are solved based on the vibration displacement to obtain the low-frequency vibration amplitude of the blade and Phase The blade tip timing vibration parameters are solved based on the vibration velocity to obtain the vibration amplitude of the blade intermediate frequency. and Phase in, The blade tip timing vibration parameters are solved based on the vibration acceleration to obtain the high-frequency vibration amplitude of the blade. and Phase in, The blade tip timing vibration parameters are solved based on the vibration acceleration to obtain the blade ultra-high frequency vibration amplitude and Phase in,

[0024]

[0025] A system for implementing the rotor blade full-frequency vibration blade tip timing measurement method comprises:

[0026] A sensor layout optimization module, which determines the number of blade tip timing sensors for measuring rotor blade vibration and the circumferential installation positions of the blade tip timing sensors based on low-frequency, medium-frequency, high-frequency and ultra-high-frequency vibration parameters of the rotor blades;

[0027] An arrival time online measurement module configured to collect an arrival time sequence of a rotor blade passing a blade tip timing sensor;

[0028] A blade tip vibration calculation module, which is connected to the arrival time online measurement module, and the blade tip vibration calculation module uses the measured time series to calculate the blade tip vibration displacement identified by low frequency, the blade tip vibration velocity identified by medium frequency, the acceleration identified by high frequency, and the jerk identified by ultra-high frequency;

[0029] A vibration parameter identification module is connected to the blade tip vibration calculation module. The vibration parameter identification module obtains the frequency, amplitude and phase of the low frequency, medium frequency, high frequency and ultra-high frequency of the rotor blade based on the blade tip vibration displacement, blade tip vibration velocity, blade tip vibration acceleration and blade tip vibration jerk through a least squares algorithm.

[0030] In the system, the interval between two adjacent blade tip timing sensors is within 10°.

[0031] Beneficial Effects

[0032] The method provided by the present invention utilizes the optimized sensor angle and the measured time series of the blade reaching the sensor to calculate the blade tip vibration displacement, blade tip vibration velocity, blade tip vibration acceleration and acceleration, thereby obtaining the different frequency enhancement components of blade vibration at low frequency, medium frequency, high frequency and ultra-high frequency, and utilizes the least squares algorithm to solve and obtain the vibration parameters of the blade in different frequency bands. Compared with the traditional blade tip timing that identifies the low-frequency vibration parameters of the blade from the vibration displacement, the present invention can realize the full-frequency domain test of the blade tip timing from low frequency, medium frequency, high frequency and ultra-high frequency; for the cases of no speed and variable speed, the displacement, velocity, acceleration and jerk measured by the blade tip timing of the present invention can still realize the full-frequency domain vibration parameter measurement, further expanding the engineering application of the blade tip timing technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0034] By reading the detailed description of the preferred specific embodiments below, various other advantages and benefits of the present invention will become clear to those of ordinary skill in the art. The drawings in the specification are only for the purpose of illustrating the preferred embodiments and are not considered to be limitations of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work. Moreover, the same reference numerals are used to represent the same components throughout the drawings.

[0035] In the attached picture:

[0036] Figure 1 A schematic flow chart of a method for identifying full-frequency-domain vibration parameters based on blade tip timing provided by an embodiment of the present invention;

[0037] Figure 2 A schematic diagram of the structure of a system for implementing the blade tip timing-based full-frequency domain vibration parameter identification method provided in one embodiment of the present invention;

[0038] Figure 3 A schematic diagram of a blade tip timing measurement system and a blade tip timing sensor layout provided for implementing an embodiment of the present invention.

[0039] The present invention is further explained below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not require further definition and explanation in subsequent drawings.

[0043] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0044] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0045] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0047] In order to enable those skilled in the art to better understand the technical solution of the present invention, Figures 1 to 3 The present invention is further described in detail. A method for measuring the timing of a rotor blade tip in full frequency range vibration comprises:

[0048] In the first step S1, the rotor blade is subjected to prestress modal analysis and low-frequency, medium-frequency, high-frequency and ultra-high-frequency modal parameters are obtained, and the number and installation angle of blade tip timing sensors are optimally determined based on the modal information;

[0049] In the second step S2, a blade tip timing sensor is circumferentially mounted on a rotor blade casing, a test is conducted and a time sequence of the rotor blade reaching the sensor is obtained, and a reference speed is determined based on the time sequence;

[0050] In the third step S3, based on the different vibration parameter identification requirements of low frequency, medium frequency, high frequency and ultra-high frequency, the measured physical quantities are converted into blade tip vibration displacement, velocity, acceleration and jerk using the arrival time and the installation angle of the sensor respectively;

[0051] In the fourth step S4, the vibration parameters based on blade tip timing are identified using the obtained physical quantities of different blade tip vibrations to obtain information such as the vibration frequency, amplitude and phase of the rotor blades at low frequency, medium frequency, high frequency and ultra-high frequency.

[0052] In the method, in the first step S1, a prestressed modal analysis is performed on the rotor blade to obtain a low-frequency modal (f L ), the intermediate frequency mode (f M ), high frequency mode within 2000Hz-5000Hz (f H ) and ultra-high frequency modes with frequencies greater than 5000Hz (f S ); Determine the number of blade tip timing sensors N according to the number m of low frequency, medium frequency, high frequency and ultra-high frequency frequency components of the rotor blade p , where N p≥2m+1;

[0053] The method, in the first step S1, according to the rotor blade low frequency (f L ), high frequency (f M ), high frequency (f H ) and ultra-high frequency (f s ) is used to construct the blade tip timing circumferential installation angle measurement matrix Θ, where the expression of the sensor measurement matrix Θ is:

[0054]

[0055] in, For N p The installation angle between the blade tip timing sensor and the speed sensor is determined; the circumferential layout of the blade tip timing sensor is optimized according to the condition number of the sensor measurement matrix, that is, cond(Θ)=||Θ||·||Θ -1 ||;

[0056] In the method, in the second step S2, the blade tip timing sensor is installed on the engine casing according to the position optimization, wherein the installation angle of the blade tip timing sensor is as small as possible under the condition of meeting the actual situation, and a blade tip timing test is carried out and the time when the blade reaches the sensor is measured;

[0057] S2011, the blade tip timing system is equipped with an OPR speed sensor, and the OPR sensor measures the time series τ OPR，n Calculate the reference speed f in the nth circle r ,in,

[0058] S2021, the blade tip timing system is not equipped with an OPR speed sensor. p N measured by the blade tip timing sensor b The arrival time series of leaves t i，b，n , using the reference speed f within the nth circle without speed reference r ,in,

[0059] In the method, in the third step S3, according to different vibration parameter identification requirements based on low frequency, medium frequency, high frequency and ultra-high frequency, the blade tip vibration displacement, velocity, acceleration and jerk are calculated using the arrival time and the installation angle of the sensor respectively;

[0060] S301, blade tip timing low-frequency vibration parameters, based on the reference speed as a reference and the sensor installation angle, obtain the ideal blade arrival time Combined with the actual arrival time of the blade passing the sensor, the time difference Δt is obtained i，b，n,in, According to the measured rotation radius R from the rotor blade tip rotation axis to the blade tip BTT The vibration displacement d of the blade tip of the blade No. b of the blade tip timing sensor No. i in the nth circle can be obtained i，b，n , where d i，b，n =2πR BTT Δt i，b，n ;

[0061] S302, blade tip timing intermediate frequency vibration parameters, based on the relationship between the blade arrival time measured by the blade tip timing sensor and the angle of the adjacent sensor installed, the vibration speed of the blade tip of the bth blade in the nth circle can be calculated using the adjacent double blade tip timing sensors No. i and No. j=i+1 and the measured arrival time sequence in,

[0062] S303, blade tip timing high frequency vibration parameters, according to the installation angles of the three adjacent blade tip timing sensors and the measured blade arrival time, the blade tip vibration velocity can be obtained, specifically, using the i-th, j=i+1-th and l=i+2-th adjacent three blade tip timing sensors and the measured arrival time sequence, the vibration acceleration of the blade tip of the b-th blade in the n-th circle can be calculated in, Where β represents the angular acceleration of the rotor;

[0063] S3031. If the rotor speed is constant, based on the blade tip vibration acceleration, when the rotor speed is constant, the rotor angular acceleration β=0, and the blade tip vibration acceleration can be expressed as: There is no need to install an additional OPR sensor at this time;

[0064] S3032: When the rotor speed is variable, based on the blade tip vibration acceleration, when the rotor speed is constant, the rotor angular acceleration β≠0, and the blade tip vibration acceleration can be expressed as:

[0065] S304, blade tip timing ultra-high frequency vibration parameters, according to the installation angle of the adjacent four blade tip timing sensors and the measured blade arrival time, the blade tip vibration acceleration can be obtained, specifically, the vibration acceleration of the blade tip of the blade in the nth circle can be calculated by using the four adjacent blade tip timing sensors of the i-th, j=i+1-th, l=i+2-th and q=i+3-th and the measured arrival time sequence. in,

[0066]

[0067] In the method, in the fourth step S4, according to the obtained blade tip vibration displacement, blade tip vibration velocity, blade tip vibration acceleration and blade tip vibration measurement response Y with different blade tip vibration accelerations, the blade tip timing vibration parameters of different frequency bands are obtained by least square method.

[0068] S501, finally obtaining blade vibration displacement parameters according to the conversion relationship between the measured blade tip vibration displacement, velocity, acceleration and jerk;

[0069] S5011. Obtain the amplitude of low-frequency vibration of blades based on vibration displacement and Phase

[0070] S5012. Obtain the amplitude of the blade intermediate frequency vibration based on the vibration velocity and Phase in,

[0071] S5013. Obtain the amplitude of the high-frequency vibration of the blade based on the vibration acceleration and Phase in,

[0072]

[0073] S5014. Obtain the amplitude of the blade ultra-high frequency vibration based on the vibration acceleration and Phase in,

[0074]

[0075] According to another aspect of the present invention, a system for implementing the full-frequency domain vibration identification method based on blade tip timing comprises:

[0076] Sensor layout optimization module: Determine the number of blade tip timing sensors for measuring the vibration of rotating blades and the circumferential installation position of blade tip timing sensors based on different parameters of blade low frequency, medium frequency, high frequency and high frequency. The sensor angle interval should be as small as possible under the condition of meeting the actual situation. It is recommended that the interval between two adjacent sensors should be within 10°;

[0077] Arrival time online measurement module: used to collect the arrival time series of blades passing through the blade tip timing sensor;

[0078] Tip vibration calculation module: according to different frequency identification requirements, the measured time series is used to calculate the tip vibration displacement of low-frequency identification, the tip vibration velocity of medium-frequency identification, the acceleration of high-frequency identification, and the jerk of ultra-high-frequency identification, and further converted into tip vibration displacement;

[0079] Vibration parameter identification module: used for obtaining the frequency, amplitude and phase of the blade's low frequency, medium frequency, high frequency and ultra-high frequency through the least squares algorithm of the above-mentioned blade tip vibration displacement, velocity, acceleration and jerk.

[0080] Finally, it should be noted that the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making any creative work are within the scope of protection of the present application.

[0081] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for measuring the timing of the blade tip of a rotor blade in the full frequency domain, characterized in that: It includes the following steps: In the first step S1, the rotor blades are subjected to prestress modal analysis and modal parameters of low frequencies with a vibration frequency less than 500 Hz, modal parameters of medium frequencies with a vibration frequency between 500 Hz and 2000 Hz, modal parameters of high frequencies with a vibration frequency between 2000 Hz and 5000 Hz, and modal parameters of ultra-high frequencies with a vibration frequency greater than 5000 Hz are obtained to determine the number and installation angle of blade tip timing sensors; The second step S2 is to install the blade tip timing sensor circumferentially on the rotor blade casing, obtain the time sequence of the rotor blade reaching the blade tip timing sensor, and determine the reference speed based on the time sequence; The third step S3 is to obtain the ideal arrival time of the blade based on the low-frequency vibration parameter less than 500 Hz according to the reference speed and the installation angle of the sensor. ,in: , is the number of blade tip timing sensors, is the blade tip timing sensor No. i, , is the number of leaves, b is the bth leaf, , N is the number of circles, n is the nth circle, Combined with the actual arrival time of the rotor blade passing the blade tip timing sensor Get time difference ,in, , based on the measured rotation radius from the rotor blade tip rotation axis to the blade tip and time difference The blade tip vibration displacement is obtained, based on the vibration parameters of the medium frequency of 500 Hz-2000 Hz, the blade tip vibration velocity is obtained according to the relationship between the measured actual blade arrival time and the angles of the adjacent installed sensors, based on the vibration parameters of the high frequency of 2000 Hz-5000 Hz, the blade tip vibration acceleration is obtained according to the installation angles of three adjacent blade tip timing sensors and the measured actual blade arrival time, based on the vibration parameters of the ultra-high frequency with a vibration frequency greater than 5000 Hz, the blade tip vibration acceleration is obtained according to the installation angles of four adjacent blade tip timing sensors and the measured actual blade arrival time, wherein the vibration parameters include frequency, amplitude and phase; The fourth step S4 is to obtain the vibration frequency, amplitude and phase of the rotor blades at low frequency, medium frequency, high frequency and ultra-high frequency using the obtained blade tip vibration displacement, blade tip vibration velocity, blade tip vibration acceleration and blade tip vibration jerk of different blade tips.

2. The method according to claim 1, characterized in that In the first step S1, a prestressed modal analysis is performed on the rotor blades to obtain a low-frequency modal vibration frequency of less than 500 Hz under a given working condition. , Medium frequency mode within 500Hz-2000Hz , high frequency mode within 2000Hz-5000Hz and ultra-high frequency modes with frequencies greater than 5000Hz According to the low frequency mode , intermediate frequency mode , high frequency mode and UHF mode The number of frequency components m determines the number of blade tip timing sensors N p ,in, .

3. The method according to claim 2, characterized in that In the first step S1, according to the low-frequency mode , intermediate frequency mode , high frequency mode and UHF mode Frequency components of blade tip timing sensor circumferential installation angle measurement matrix , where the angle measurement matrix The expression is: ， in, For the The installation angle between the blade tip timing sensor and the speed sensor is determined according to the condition number of the angle measurement matrix. .

4. The method according to claim 1, characterized in that In the second step S2, an OPR speed sensor is installed to measure the time series , based on time series Calculate the Base speed in the circle ,in, .

5. The method according to claim 1, characterized in that: In the second step S2, according to The blade tip timing sensor measures The actual arrival time of the blade , No. Base speed in the circle for: 。 6. The method according to claim 5, characterized in that The third step S3 comprises, S301, based on the low-frequency vibration parameters less than 500 Hz, according to the measured rotation radius from the rotor blade tip rotation axis to the blade tip Get the Tip timing sensor No. The tip of leaf No. Vibration displacement in the ring ,in, , where the time difference ; S302, based on the vibration parameters of the intermediate frequency of 500Hz-2000Hz, using the No. and The adjacent double blade end timing sensors and the measured actual arrival time are used to calculate the first The tip of leaf No. Vibration speed in the circle ,in, , Respectively No. and The installation angle between the blade tip timing sensor and the speed sensor, Actual arrival time of blade tip timing sensor , No. Actual arrival time of blade tip timing sensor ; S303, based on the high frequency vibration parameters of 2000Hz-5000Hz, using the No. No. and The three adjacent blade tip timing sensors and the measured actual arrival time are used to calculate the first The tip of leaf No. Vibration acceleration in the ring ,in, ,in, represents the angular acceleration of the rotor; if the rotor speed is constant, based on the blade tip vibration acceleration, when the rotor speed is constant, the angular acceleration of the rotor , at this time, the blade tip vibration acceleration is expressed as: When the rotor speed is variable, based on the blade tip vibration acceleration, when the rotor speed is constant, the rotor angular acceleration , at this time, the blade tip vibration acceleration is expressed as: ; S304, based on the vibration parameters of the ultra-high frequency with a vibration frequency greater than 5000 Hz, using the No. No. and The four adjacent blade tip timing sensors and the measured actual arrival time series are used to calculate the first The tip of leaf No. Vibration jerk in the ring ,in, 。 7. The method according to claim 3, characterized in that In the fourth step S4, a blade tip vibration measurement response is generated according to the blade tip vibration displacement, blade tip vibration velocity, blade tip vibration acceleration and blade tip vibration jerk. The blade tip timing vibration parameters of different frequency bands are obtained by least square method. .

8. The method according to claim 7, characterized in that The blade tip timing vibration parameters are solved based on the vibration displacement to obtain the low-frequency vibration amplitude of the blade and Phase Based on the vibration velocity, the blade tip timing vibration parameters are solved to obtain the vibration amplitude of the blade intermediate frequency. and Phase ,in, , ; Based on the vibration acceleration, the blade tip timing vibration parameters are solved to obtain the high-frequency vibration amplitude of the blade and Phase ,in, , ; Based on the vibration acceleration, the blade tip timing vibration parameters are solved to obtain the ultra-high frequency vibration amplitude of the blade and Phase ,in, , .

9. A system for implementing a rotor blade full-frequency vibration blade tip timing measurement method according to any one of claims 1 to 8, characterized in that: These include, A sensor layout optimization module, which determines the number of blade tip timing sensors for measuring rotor blade vibration and the circumferential installation positions of the blade tip timing sensors based on low frequency, medium frequency, high frequency and ultra-high frequency modal parameters of the rotor blades; An arrival time online measurement module configured to collect an arrival time sequence of a rotor blade passing a blade tip timing sensor; A blade tip vibration calculation module, which is connected to the arrival time online measurement module and the sensor layout optimization module, and the blade tip vibration calculation module uses the measured time series to calculate the blade tip vibration displacement identified by low frequency, the blade tip vibration velocity identified by medium frequency, the acceleration identified by high frequency, and the jerk identified by ultra-high frequency; A vibration parameter identification module is connected to the blade tip vibration calculation module and the arrival time online measurement module. The vibration parameter identification module obtains the frequency, amplitude and phase of the low frequency, medium frequency, high frequency and ultra-high frequency of the rotor blade based on the blade tip vibration displacement, blade tip vibration velocity, blade tip vibration acceleration and blade tip vibration jerk through a least squares algorithm.

10. The system according to claim 9, characterized in that The interval between two adjacent blade tip timing sensors is within 10°.

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