Hierarchical alarm method and system adapted to wind turbine resonance

Abstract

A hierarchical alarm method and system adapted to wind turbine resonance, relating to the technical field of wind power. The method comprises: performing a wind turbine frequency tap test, and calculating an average natural frequency of all blades and a natural frequency of a wind turbine; calculating a rotation frequency at a rated rotation speed on the basis of a rated operating rotation speed, and calculating rotation frequencies and passing frequencies at different operating rotation speeds; comparing the rotation frequencies and passing frequencies at different operating rotation speeds with the natural frequency of the wind turbine, so as to determine a resonance interference rotation speed; establishing a scoring system, and calculating a score for a current operating state; and determining an alarm level on the basis of the score for the current operating state, and triggering an alarm. The present invention allows for comprehensive determination on the basis of the global characteristics of the system and issuing of a warning for vibration caused by resonance, and can be further extended to be compatible with an automatic adjustment means, thereby achieving integrated automatic control of alarming and avoidance.

Description

A hierarchical alarm method and system adapted to fan resonance TECHNICAL FIELD

[0001] The present application relates to the field of wind power technology, and particularly to a hierarchical alarm method and system adapted to fan resonance. BACKGROUND

[0002] In the current power industry, speed regulation operation of rotating machinery is widely used, not only in large fans, but also in high-power pumps. However, when the rotating machine adopts speed regulation operation, its inherent frequency will inevitably interfere with the rotating frequency and the passing frequency to produce resonance. When resonance is excited, it will cause great harm to the equipment itself. In recent years, the frequent rotor rupture, main shaft rupture and bearing damage accidents of power plant fans are mostly caused by resonance, which seriously affects the safety and economic benefits of power enterprises, and also causes great obstacles to social livelihood and industrial development.

[0003] With the current technology, it is almost impossible to eliminate the resonance of the equipment. For the equipment whose resonance frequency has been determined, it can still be avoided by adjusting means. Even so, as the equipment operates, wear and tear, dust accumulation and other factors will cause changes in its inherent frequency, so it needs to be adjusted regularly according to the actual situation of the equipment, which has great limitations. SUMMARY

[0004] In view of the problem that when resonance is excited, it will cause great harm to the equipment itself, the present application is proposed.

[0005] Therefore, the problem to be solved by the present application is how to make a comprehensive evaluation alarm strategy by analyzing the inherent frequency and considering the difficulty of resonance excitation and the intensity of harm in the case of known equipment inherent frequency.

[0006] To solve the above technical problems, the present application provides the following technical solutions:

[0007] In a first aspect, the present application provides a hierarchical alarm method adapted to fan resonance, which comprises: performing a fan frequency knock test, calculating the average inherent frequency of all blades and the inherent frequency of the fan; calculating the rotating frequency under the rated rotating speed according to the rated rotating speed, and calculating the rotating frequency and the passing frequency under different rotating speeds; comparing the rotating frequency and the passing frequency under the different rotating speeds with the inherent frequency of the fan to determine the resonance interference rotating speed; establishing a scoring system and calculating the score of the current operating state; determining the alarm level according to the score of the current operating state, and triggering the alarm and recording.

[0008] As a preferred scheme of the hierarchical alarm method adapted to fan resonance, wherein: the calculation of the average natural frequency of all blades comprises the following steps: selecting m0 test points on the fan blade; using an eddy current sensor to perform a knock test at each test point; recording the 1st to n th order natural frequencies of each test point, and performing square averaging on the data of the m0 test points to calculate the average natural frequency of the blade; wherein m0 is a constant.

[0009] As a preferred scheme of the hierarchical alarm method adapted to fan resonance, wherein: the calculation of the natural frequency of the fan is performed by performing arithmetic squaring on the natural frequencies of all blades.

[0010] As a preferred scheme of the hierarchical alarm method adapted to fan resonance, wherein: the calculation of the rotational frequency according to the rated operating rotational speed is performed according to the rated operating rotational speed n e The calculation of the rotational frequency (Hz): υ r = n e / 60

[0011] In combination with the number of blades M of the fan, the passage frequency of the fan at the rated rotational speed is calculated: υ t = υ r × M

[0012] The calculation of the rotational frequency and the passage frequency at different operating rotational speeds comprises: according to the multiple relationship, the N times υ t and υ r of the fan at the rated rotational speed are obtained; when the rotational speed of the fan is increased from 0 to n e , there are 0, 1, 2,..., n e rotational frequencies and passage frequencies, denoted as υ t，N and υ r，N .

[0013] As a preferred scheme of the hierarchical alarm method adapted to fan resonance, wherein: the scoring system comprises a vibration monitoring condition score POV, a resonance excitation score PORE, and a resonance rotational speed deviation score DORE; the calculation of the scoring system adopts a scoring method of (PORE×DORE+POV).

[0014] As a preferred scheme of the hierarchical alarm method adapted to fan resonance, wherein: when the scoring system is implemented, the fan operation has the following situations: if the rotational speed of the fan is located at the core position of resonance occurrence, i.e., the deviation degree and the vibration exceeds the alarm value; if the rotational speed of the fan is located at the core position of resonance occurrence, i.e., the deviation degree but the vibration does not exceed the alarm value; if the rotational speed of the fan is located at a higher position of resonance occurrence, i.e., (3% < deviation degree ) but the vibration exceeds the alarm value; if the fan speed is located at a higher position of resonance occurrence (3% < offset degree < 5%), but the vibration does not exceed the alarm value; if the fan speed is located at a safe position (offset degree < 3%), but the vibration exceeds the alarm value; and different scores are output according to different fan operation conditions. ) but the vibration exceeds the alarm value; if the fan speed is located at a higher position of resonance occurrence (3% < offset degree < 5%), but the vibration does not exceed the alarm value; if the fan speed is located at a safe position (offset degree < 3%), but the vibration exceeds the alarm value; and different scores are output according to different fan operation conditions. ) but the vibration exceeds the alarm value; if the fan speed is located at a higher position of resonance occurrence (3% < offset degree < 5%), but the vibration does not exceed the alarm value; if the fan speed is located at a safe position (offset degree < 3%), but the vibration exceeds the alarm value; and different scores are output according to different fan operation conditions.

[0015] As a preferred solution of the grading alarm method adapted to fan resonance, the alarm comprises setting a multi-color alarm, displaying an alarm button on a DCS screen, and performing entry accumulation statistics of alarm time in the background.

[0016] In a second aspect, the embodiments of the present application provide a grading alarm system adapted to fan resonance, which comprises: a frequency knock test module for performing a fan frequency knock test, calculating average natural frequencies of all blades, and obtaining a fan natural frequency; a rotating frequency calculation module for calculating a rotating frequency under a rated rotating speed according to the rated rotating speed, and calculating rotating frequencies and passing frequencies under different rotating speeds; a frequency matching and resonance detection module for comparing the rotating frequencies and the passing frequencies under the different rotating speeds with the fan natural frequency, and determining a resonance interference speed; a sub-system module for establishing a scoring system and calculating a score of a current operating state; and an alarm triggering and recording module for determining an alarm level according to the score of the current operating state, and triggering an alarm.

[0017] In a third aspect, the embodiments of the present application provide a computer device comprising a memory and a processor, wherein the memory stores a computer program, and the computer program instructs the processor to implement the steps of the grading alarm method adapted to fan resonance according to the first aspect of the present application.

[0018] In a fourth aspect, the embodiments of the present application provide a computer readable storage medium having a computer program stored thereon, wherein the computer program instructs a processor to implement the steps of the grading alarm method adapted to fan resonance according to the first aspect of the present application.

[0019] The present application has the following beneficial effects: the present application adopts a comprehensive scoring mechanism to perform alarm according to known resonance frequencies, in combination with a certain avoidance rate and real-time monitoring data of fan vibration, gives an operating personnel a device operation warning, judges vibration jumps generated in the same current and historical state of the device, issues a warning, and collects information in the comprehensive scoring mechanism to perform alarm. It can be seen that the present application comprehensively judges from the overall characteristics of the system, issues a warning for vibration generated by resonance, and can continue to expand and be compatible with automatic adjustment means to achieve integrated automatic control of alarm + avoidance. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0021] Fig. 1 is a hierarchical alarm configuration diagram adapted to fan resonance.

[0022] Fig. 2 is a schematic diagram of a fan blade knock point. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned purposes, features and advantages of the present application more apparent and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings.

[0024] In the following description, a large number of specific details are set forth in order to facilitate a thorough understanding of the present application, but the present application can also be implemented in other ways different from the description, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0025] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0026] Embodiment 1

[0027] Referring to Figs. 1-2, the first embodiment of the present application provides a hierarchical alarm method adapted to fan resonance, comprising,

[0028] S1: Perform fan frequency knock test, calculate the average natural frequency of all blades and the natural frequency of the fan.

[0029] S1.1: Select m0 test points on the fan blade, wherein m0 of the present application is 4 (TAP POINT 1-4).

[0030] Among them, the test points are located at 1 / 2 of the blade height h, and the four test points are located at 1 / 5h, 2 / 5h, 3 / 5h and 4 / 5h of the blade height h.

[0031] S1.2: Use an eddy current sensor to perform knock test at each test point.

[0032] As shown in Fig. 2, the eddy current sensor is adsorbed at each TAP POINT position, and a knock is applied to the blade to excite the inherent frequency (υ g，1x ~υ g，nx ) of the blade itself, wherein υ g，1x represents the 1st order inherent frequency of the blade, and υ g，nx represents the nth order inherent frequency of the blade.

[0033] S1.3: Record and calculate the inherent frequency of each blade.

[0034] Record the 1st to nth order inherent frequencies (υ g，1x，1 ~υ g，nx，1 , υ g，1x，2 ~υ g，nx，2 , υ g，1x，3 ~υ g，nx，3 , υ g，1x，4 ~υ g，nx，4 , etc.) of each test point, square average the data of the four test points, and obtain the average inherent frequency (υ g，1x，avg ~υ g，nx，avg ) of the blade.

[0035] S1.4: Calculate the average inherent frequency of all blades to obtain the inherent frequency of the fan.

[0036] Arithmetically square the inherent frequencies of all blades to finally obtain the inherent frequency υ g,f， 1x ~υ g,f，nx of the fan.

[0037] S2: Calculate the rotation frequency at the rated rotation speed according to the rated rotation speed, and calculate the rotation frequency and the passing frequency at different rotation speeds.

[0038] Preferably, the rotation frequency is calculated according to the rated rotation speed n e : υ r = n e / 60, which is in Hz (Hertz), and the passing frequency of the fan at the rated rotation speed is calculated in combination with the number of blades M of the fan: υ t = υ r ×M

[0039] At the same time, the N times υ t and υ r of the fan at the rated rotation speed can be obtained according to the ratio relationship;

[0040] Similarly, when the rotation speed of the fan is increased from 0 to n e at the rated rotation speed, there will be (0, 1, 2..., n e ) rotation frequencies and passing frequencies, denoted as υ t，N and υr，N .

[0041] S3: compare the rotating frequency and the passing frequency under different running speeds and the inherent frequency of the fan to determine the resonance interference speed.

[0042] Compare the calculated rotating frequency υ t，N , the passing frequency υ r，N and the inherent frequency of the fan, when close to or even equal to the inherent frequency of a certain order of the fan, it is considered that the rotating frequency υ r，N and the passing frequency υ t，N corresponding to the fan speed is the resonance interference speed.

[0043] S4: Establish a scoring system and calculate the score of the current running state.

[0044] As can be seen from FIG. 1, the configuration of the present application mainly consists of three parts, including: POV is the vibration monitoring condition score, which evaluates the vibration output monitored in real time by the system and outputs the evaluation result;

[0045] PORE is the resonance excitation score, which evaluates the output when the monitoring speed reaches res1x~res4x, the speed gear, by correctly selecting the monitoring speed and through function conversion.

[0046] DORE is the resonance speed deviation score, which evaluates the deviation degree between the selected resonance speed interval and the actual speed, and finally obtains the evaluation.

[0047] From the intensity of resonance, the general principle is that resonance phenomenon induced by any reason should be avoided, and the lower the order of the inherent frequency of the equipment, the easier the resonance is excited, and the higher the order, the more difficult the resonance phenomenon is excited, so the resonance phenomenon caused by the inherent frequency of the equipment should be rated according to the difficulty of excitation, that is, the resonance caused by the first order inherent frequency is rated as level one, and so on, and the resonance caused by the fourth order inherent frequency is rated as level four.

[0048] The first to fourth order inherent frequencies of the equipment are defined as Res 1X ~Res 4X , and the corresponding resonance caused by excitation Res 1X ~Res 4X is defined as Lvr1~Lvr4.

[0049] At the same time, the speed that will excite the resonance of the equipment is defined as Rev, and there may be more than one speed point that may excite the resonance in rotating machinery, so according to the number of speed points, it is defined as Rev1~Rev n1 , wherein n1 is the number of resonance speed points.

[0050] Further, the resonance excitation condition score (PORE) is:

[0051] According to the difficulty of excitation of the natural frequency, Rev n Res 1X ~Res 4X The phenomenon of mutual interference of the levels is assigned 7-4 points in turn, and generally Res 1X Most easily excited, score 4, Res 4X Most difficult to be excited, the score is 7.

[0052] The resonance speed deviation condition score (DORE) is:

[0053] According to the offset degree of the resonance speed, when the actual operating speed of the fan and the resonance speed deviation degree is within 1%, it is recorded as 5 points; when the deviation degree is within 3%, it is recorded as 4 points; when the deviation degree is within 5%, it is recorded as 3 points; other speed intervals are recorded as 0 points.

[0054] Among them, the deviation degree is the any week vibration speed n x of the fan, and the actual speed n s of the fan, recorded as:

[0055] The vibration monitoring condition score (POV) is:

[0056] According to the DCS monitoring vibration data, 10 points are reached for the alarm value, 8 points are reached for 80% of the alarm value, and so on.

[0057] Preferably, the calculation of the scoring system includes:

[0058] The scoring method of (PORE×DORE+POV) is adopted.

[0059] When the system is implemented, the operation of the fan will present the following situations:

[0060] a. If the fan speed is located in the core position of resonance occurrence, that is, the deviation degree And the vibration exceeds the alarm value, the system score output is 45 points;

[0061] b. If the fan speed is located in the core position of resonance occurrence, that is, the deviation degree But the vibration does not exceed the alarm value, the system score output is 40 points;

[0062] c. If the fan speed is located in the higher position of resonance occurrence, that is, (3%< deviation degree ), but the vibration exceeds the alarm value, the system score output is 34 points;

[0063] d. If the fan speed is located at the higher position of resonance occurrence (3% < offset < 5%), but the vibration does not exceed the alarm value, the system score output is 29 points;

[0064] e. If the fan speed is located at the safe position (offset < 3%), but the vibration exceeds the alarm value, the system score output is 10 points.

[0065] S5: Determine the alarm level according to the score of the current running state, and trigger the alarm and record.

[0066] Specifically, if the score is greater than or equal to 40 points, a red alarm is triggered, indicating that the fan has entered the core point of resonance and has a great impact on the fan operation;

[0067] If the score is greater than or equal to 20 points and less than 40 points, an orange alarm is triggered, indicating that the fan has entered a high resonance area and has a certain impact on the fan operation.

[0068] If the score is greater than 10 points and less than 20 points, a yellow alarm is triggered, indicating that the fan has just entered the resonance range, but the monitoring data does not necessarily reflect the abnormality of the fan running state.

[0069] If the score is less than or equal to 10 points, a green running state is triggered, indicating that the fan is not running in the resonance area, and the score of the fan only represents the vibration influence caused by other factors.

[0070] The red, orange, and yellow alarms not only display the alarm button on the DCS screen, but also should perform the entering and cumulative statistics of the alarm time in the background.

[0071] Further, the embodiment also provides a hierarchical alarm system adapted to fan resonance, comprising,

[0072] A frequency knock test module for performing a fan frequency knock test, calculating the average natural frequency of all blades, and obtaining the natural frequency of the fan;

[0073] A rotating frequency calculation module for calculating the rotating frequency at the rated speed according to the rated running speed, and calculating the rotating frequency and the passing frequency at different running speeds;

[0074] A frequency matching and resonance detection module for comparing the rotating frequency and the passing frequency at different running speeds with the natural frequency of the fan to determine the resonance interference speed;

[0075] A subsystem module for establishing a scoring system and calculating the score of the current running state;

[0076] An alarm triggering and recording module for determining the alarm level according to the score of the current running state and triggering the alarm.​​

[0077] The embodiment also provides a computer device suitable for the hierarchical alarm method adapted to fan resonance, including a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions to realize the hierarchical alarm method adapted to fan resonance proposed in the above embodiment.

[0078] The computer device can be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected through a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The communication interface of the computer device is used to communicate with external terminals in a wired or wireless manner. The wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer overlaid on the display screen, or a key, trackball or touchpad arranged on the shell of the computer device, or an external keyboard, touchpad or mouse, etc.

[0079] The embodiment also provides a storage medium having a computer program stored thereon, and the program is executed by a processor to realize the hierarchical alarm method adapted to fan resonance proposed in the above embodiment.

[0080] To sum up, according to the known resonance frequency, in combination with a certain avoidance rate and real-time monitoring data of vibration of the fan, the alarm is performed by using a comprehensive scoring mechanism, the running personnel is given a warning of the operation of the equipment, and the vibration jump generated at present is judged according to the current and historical states of the equipment under the same operation, and a warning is issued, and information is collected in the comprehensive scoring mechanism to perform alarm. As can be seen, the comprehensive judgment is made from the overall characteristics of the system, the vibration situation of the resonance is warned, and the subsequent automatic adjustment means is compatible, so that the alarm + avoidance integrated automatic control is achieved.

[0081] Embodiment 2

[0082] Referring to FIG. 1 and FIG. 2, a second embodiment of the present application is provided, and the embodiment provides a hierarchical alarm method adapted to fan resonance. In order to verify the beneficial effects of the present application, scientific demonstration is performed through experiments.

[0083] In order to verify the effectiveness of the hierarchical alarm method adapted to the fan resonance, three fans of FX3000 type are selected as test objects, which are named as fan A, fan B and fan C. The resonance characteristics of the fan at different rotating speeds are verified by measuring and analyzing the natural frequency of the fan blade and the resonance point of the fan, and the alarm triggering is realized through the scoring system.

[0084] Firstly, the fan blade is tested by using the eddy current sensor. Four test points (TAP POINT 1-4) are arranged on each blade, which are located at 1 / 5h, 2 / 5h, 3 / 5h and 4 / 5h of the blade height and 1 / 2 of the width w. The natural frequency of each test point is calculated by exciting the natural frequency of the blade, and the square average of the data is obtained to get the average value of the natural frequency of each blade. Then, the arithmetic square of the average value of the natural frequency of all blades is calculated to obtain the natural frequency of the whole fan.

[0085] The rotating frequency ur and the passing frequency ut of the fan are calculated by the rated rotating speed of the fan. At the same time, the resonance frequency changes at different rotating speeds are recorded in the process of the rotating speed from 0 to the rated rotating speed, and the key resonance interference rotating speed region is marked.

[0086] By comparing the rotating frequency, passing frequency and its multiple frequency of the fan with the natural frequency of the fan, the rotating speed of the fan in the resonance region is identified, and the running state of the fan is scored through the scoring system. The three elements of the score include the vibration monitoring condition score (POV), the resonance excitation score (PORE) and the resonance rotating speed deviation score (DORE), which are evaluated according to different rotating speeds and vibration conditions.

[0087] Finally, the scoring system triggers the corresponding alarm level and records the alarm time according to different score values. When the score exceeds 40 points, the red alarm is triggered, indicating that the fan is in a serious resonance state; when the score is 2040 points, the orange alarm is triggered, indicating that the fan is in a higher resonance influence region; when the score is 1020 points, the yellow alarm is triggered; and when the score is less than or equal to 10 points, the green alarm is triggered, indicating that the fan is running normally.

[0088] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit it. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application, which should be covered in the scope of the claims of the present application.

Claims

1. A method of graduated alerting adapted to fan resonance, characterized in that: comprising, performing a fan frequency knock test, calculating the average natural frequency of all blades and the natural frequency of the fan; calculating the rotational frequency at the rated operating speed according to the rated operating speed, and calculating the rotational frequency and the passing frequency at different operating speeds; comparing the rotational frequency and the passing frequency at the different operating speeds and the natural frequency of the fan to determine the resonance interference rotation; establishing a scoring system and calculating the score of the current operating state; determining the alarm level according to the score of the current operating state and triggering the alarm.

2. The hierarchical alarm method adapted to fan resonance of claim 1, wherein: The calculation of the average natural frequency of all blades includes the following steps: selecting m0 test points on the fan blades; performing a knock test at each test point using an eddy current sensor; recording the first to n-th order natural frequencies of each test point, and calculating the average natural frequency of the blade by square averaging the data of the m0 test points; wherein m0 is a constant.

3. The hierarchical alarm method adapted to fan resonance of claim 2, wherein: The calculation of the natural frequency of the fan is by arithmetic square of the natural frequencies of all blades.

4. The hierarchical alarm method adapted to fan resonance of claim 3, wherein: The calculation of the rotational frequency at the rated operating speed is: According to the rated operating rotational speed n e Calculated rotational frequency (Hz): υ r = n e / 60 combined with the number of blades M of the fan, the passing frequency of the fan at the rated operating speed is calculated: υ t = υ r x M The calculation of the rotational frequency and the passing frequency at different operating speeds includes: According to the relationship of the ratio, the N times of υ of the fan under the rated speed is obtained t and υ r ; When the fan speed is raised from 0 to the rated speed under n e , there will be (0, 1, 2,..., n e ) rotation frequencies and through frequencies, denoted as υ t，N and υ r，N .

5. The hierarchical alarm method adapted to fan resonance of claim 4, wherein: The scoring system includes vibration monitoring condition score POV, resonance excitation score PORE and resonance speed deviation score DORE; The scoring system uses a scoring method of (PORE×DORE+POV).

6. The hierarchical alarm method adapted to fan resonance of claim 5, wherein: When the scoring system is implemented, the fan operation has the following situations: If the fan speed is located in the core position of resonance occurrence, i.e. the offset degree and the vibration exceeds the alarm value; If the fan speed is located in the core position of resonance occurrence, i.e. the offset degree but the vibration does not exceed the alarm value; If the fan speed is located at a higher position of resonance occurrence, i.e. (3% < deviation < 5%) ), but the vibration exceeds the alarm value; If the fan speed is at a higher position where resonance occurs (3% < offset) ), but the vibration does not exceed the alarm value; If the fan speed is in the safe position (offset degree ), but the vibration exceeds the alarm value; Different scores are output according to different fan operating conditions.

7. The step alarm method adapted to fan resonance of claim 6, wherein: The alarm includes: setting a three-color alarm, displaying an alarm button on the DCS screen, and performing background alarm time entry accumulation statistics to calculate the cumulative time of the fan entering the resonance interval, provide data basis for the interval of fan impeller inspection.

8. A hierarchical alarm system adapted to fan resonance, based on the hierarchical alarm method adapted to fan resonance according to any one of claims 1 to 7, characterized in that: Further comprising, a frequency knock test module for performing a fan frequency knock test, calculating the average natural frequency of all blades, and obtaining the natural frequency of the fan; a rotational frequency calculation module for calculating the rotational frequency at the rated operating speed according to the rated operating speed, and calculating the rotational frequency and the passing frequency at different operating speeds; a frequency matching and resonance detection module for comparing the rotational frequency and the passing frequency at the different operating speeds and the natural frequency of the fan to determine the resonance interference rotation; a scoring system module for establishing a scoring system and calculating the score of the current operating state; an alarm triggering and recording module for determining the alarm level according to the score of the current operating state and triggering the alarm. 9.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is characterized in that: The processor executes the computer program to realize the steps of the hierarchical alarm method adapted to the resonance of the fan according to any one of claims 1-7.

10. A computer readable storage medium having stored thereon a computer program, characterized in that: The computer program is executed by the processor to realize the steps of the hierarchical alarm method adapted to the resonance of the fan according to any one of claims 1-7.

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