阅读说明：本技术 一种针对转子稳定热不平衡振动的动平衡方法及装置 (Dynamic balance method and device for stable thermal unbalance vibration of rotor ) 是由 陈悦 阮圣奇 张辉 李建华 刘海东 章正林 陈胜利 吴仲 马宏 肖宇煊 庞靖 于 2021-08-03 设计创作，主要内容包括：本发明公开了一种针对转子稳定热不平衡振动的动平衡方法及装置,所述方法包括：在汽轮发电机组架设具备相位分析功能的数据采集分析仪；汽轮发电机组冲转过程中,通过数据采集分析仪测量轴瓦的轴振数据；确定试加重角度；利用试加重角度对汽轮发电机组加重,根据加重前后的振动向量以及预设的初始试加重向量确定动平衡影响系数；建立汽轮发电机组不同工况下振动向量、动平衡影响系数以及待加重向量之间的关系；采用最小二乘法获取待加重向量,使得汽轮发电机组各工况下残余振动向量最小；本发明的优点在于：适用于热不平衡振动场景,不存在降低某一工况下的振动,而导致另一工况振动升高的可能性。(The invention discloses a dynamic balance method and a dynamic balance device aiming at stable thermal unbalance vibration of a rotor, wherein the method comprises the following steps: erecting a data acquisition analyzer with a phase analysis function on a steam turbine generator unit; in the process of the impact rotation of the steam turbine generator unit, measuring shaft vibration data of a bearing bush through a data acquisition analyzer; determining a trial weighting angle; weighting the turbo generator set by using the trial weighting angle, and determining a dynamic balance influence coefficient according to vibration vectors before and after weighting and a preset initial trial weighting vector; establishing a relation among a vibration vector, a dynamic balance influence coefficient and a vector to be weighted under different working conditions of the steam turbine generator unit; obtaining a vector to be weighted by adopting a least square method, so that the residual vibration vector of the steam turbine generator unit under each working condition is minimum; the invention has the advantages that: the method is suitable for thermal unbalance vibration scenes, and the possibility that vibration is reduced under a certain working condition and vibration is increased under another working condition does not exist.)

1. A dynamic balancing method for stabilizing thermally unbalanced vibrations of a rotor, the method comprising:

the method comprises the following steps: erecting a data acquisition analyzer with a phase analysis function on a steam turbine generator unit;

step two: in the process of the steam turbine generator unit rotating, the shaft vibration data of the bearing bush is measured through the data acquisition analyzer, and the vibration vector before weighting is recordedAnd a phase angle α;

step three: determining a trial weighting angle theta according to the phase angle alpha, wherein the trial weighting angle represents a weighting angle in the test process;

step four: weighting the turbo generator set by using the trial weighting angle, and determining a dynamic balance influence coefficient according to vibration vectors before and after weighting and a preset initial trial weighting vector;

step five: establishing a relation among a vibration vector, a dynamic balance influence coefficient and a vector to be weighted under different working conditions of the steam turbine generator unit;

step six: and obtaining the vector to be weighted by adopting a least square method, so that the residual vibration vector of the steam turbine generator unit under each working condition is minimum.

2. The dynamic balancing method for stabilizing thermally unbalanced vibrations of a rotor according to claim 1, wherein the third step comprises:

and acquiring a trial weighting angle by using a formula theta which is alpha + beta-180-gamma, wherein beta is an included angle between a key phase probe and a shaft vibration probe of the steam turbine generator unit, and gamma is a mechanical lag angle.

3. The dynamic balancing method for stabilizing thermally unbalanced vibrations of a rotor according to claim 2, wherein the key phase probe is rotated in a positive direction after the shaft vibrating probe, and in a negative direction after the shaft vibrating probe.

4. A method of dynamic balancing of thermally stable unbalance vibrations of a rotor according to claim 2, characterized in that the mechanical lag angle is determined from the relation of the dynamic balancing rotational speed, which is acute below the critical rotational speed, and the critical rotational speed, which is obtuse above the critical rotational speed.

5. The dynamic balancing method for stabilizing thermally unbalanced vibrations of a rotor according to claim 1, wherein the fourth step comprises:

according to the vibration vectors before and after weighting and the preset initial trial weighting vector, using a formulaDetermining a dynamic balance impact coefficient, wherein,in order to obtain a weighted vibration vector,is a preset initial trial weight vector.

6. A dynamic balancing method for stabilizing thermally unbalanced vibrations of a rotor according to claim 1, wherein the step five comprises:

in the process of loading the turbonator set, measuring the shaft vibration data under different working condition loads, and respectively recording the shaft vibration data as a sequence

The corresponding load vibration vectors after the load is weighted under different working condition loads are as follows:

wherein the content of the first and second substances,representing the vector to be emphasized.

7. A method of dynamic balancing of thermally unbalanced vibrations to a rotor according to claim 6, characterized in that the different operating condition loads represent from no load to full load.

8. The dynamic balance method for stabilizing thermally unbalanced vibration of a rotor according to claim 1, wherein the data acquisition analyzer having a phase analysis function is a phase analyzer.

9. A dynamic balancing apparatus for stabilizing thermally unbalanced vibrations of a rotor, the apparatus comprising:

the acquisition module is used for erecting a data acquisition analyzer with a phase analysis function on the steam turbine generator unit;

the measuring module is used for measuring the shaft vibration data of the bearing bush through the data acquisition analyzer in the process of the rotation of the steam turbine generator unit and recording the vibration vector before weightingAnd a phase angle α;

the trial weighting angle acquisition module is used for determining a trial weighting angle theta according to the phase angle alpha, and the trial weighting angle represents a weighting angle in the test process;

the dynamic balance influence coefficient acquisition module is used for weighting the steam turbine generator unit by using the trial weighting angle and determining a dynamic balance influence coefficient according to vibration vectors before and after weighting and a preset initial trial weighting vector;

the relation building module is used for building the relation among the vibration vector, the dynamic balance influence coefficient and the vector to be weighted under different working conditions of the steam turbine generator unit;

and the control module is used for acquiring the vector to be weighted by adopting a least square method so that the residual vibration vector of the steam turbine generator unit under each working condition is minimum.

10. The dynamic balancing apparatus for stabilizing thermally unbalanced vibrations of a rotor of claim 9, wherein the trial weighting angle obtaining module is further configured to:

and acquiring a trial weighting angle by using a formula theta which is alpha + beta-180-gamma, wherein beta is an included angle between a key phase probe and a shaft vibration probe of the steam turbine generator unit, and gamma is a mechanical lag angle.

Technical Field

The invention relates to the technical field of fault diagnosis and control of rotating equipment, in particular to a dynamic balance method and a dynamic balance device for stable thermal unbalance vibration of a rotor.

Background

For a large thermal generator set, high-temperature and high-pressure steam passes through a fixed nozzle to become accelerated airflow and then is sprayed onto blades, so that a rotor provided with a blade row rotates, and meanwhile, the generator does work to generate electric energy. In industrial production, bending of the main shaft of the rotor of the steam turbine generator unit can be caused for various reasons:

(1) the main shaft and the stationary member rub against each other, and near the rubbing point, the main shaft expands due to frictional heat, and generates a reverse compressive stress, which causes the shaft to bend.

(2) In the manufacturing process, residual stress still exists in the main shaft due to improper heat treatment or poor processing. After the spindle is installed in the cylinder, this residual stress may be partially or completely removed during operation, causing the shaft to bend.

(3) The shaft is bent due to poor maintenance. 1) The axial clearance of the through-flow part is not properly adjusted, so that the baffle plate and the impeller or other parts generate single-side friction in the running process, and the shaft is locally overheated and bent. 2) The shaft seal clearance and the clapboard steam seal clearance are too small or uneven, and the shaft is bent due to the friction between the shaft seal clearance and the clapboard steam seal clearance after being started. 3) The rotor center is not aligned, the sliding pin system is not cleaned, or the rotor mass imbalance is not eliminated, so that during starting, large vibrations are generated, and the main shaft and the static part are rubbed to be bent. 4) The steam seal door or the speed regulation valve has poor maintenance quality and has steam leakage, so that the shaft is locally heated and bent due to the steam leakage in the turbine in the shutdown process.

(4) Improper operation causes the shaft to bend. 1) After the steam turbine rotor stops, because the cooling speed of the cylinder and the rotor is different, and the cooling speed of the lower cylinder is higher than that of the upper cylinder, the temperature difference between the upper cylinder and the lower cylinder is formed, so that the upper part of the rotor is hot than the lower part of the rotor, and the lower part of the rotor contracts quickly, so that the shaft bends upwards. This is elastic bending, and the rotor recovers to the original state after the temperature difference between the upper and lower cylinders disappears. 2) After the engine is stopped, the elastic bending of the shaft is not recovered and is started again, the warm-up time is not enough, the shaft is still in an elastic bending state, and vibration can occur after the engine is started. When the shaft is seriously deformed, the main shaft and the shaft sealing sheet are rubbed, so that the shaft is locally heated to generate uneven thermal expansion, thereby causing permanent bending deformation. 3) When the steam turbine is started, the rotor sends steam to the shaft seal for warming before rotating, or the steam entering the shaft seal is too much due to too high vacuum pumping during starting, the steam sending time is too long, and the like, the inside of the cylinder is heated up and cooled down, and the rotor is heated unevenly to generate bending deformation. 4) When water impact occurs during operation, the thrust of the rotor is increased, large unbalanced torque is generated, the rotor vibrates violently, and friction occurs between the partition plate and the impeller and between the movable blade and the stationary blade, so that bending is caused.

(5) The generator rotor cools unevenly. The generator rotor has a cooling air duct, and the cooling air volume is reduced due to reasons such as maintenance and equipment failure in a part of the cooling air duct, so that the circumferential cooling of the rotor is uneven, and the thermal bending is possibly caused.

(6) The generator rotor coil is hindered from expanding. The damage of a slip layer in the operation of a part of generator rotors causes the expansion of a rotor coil at the axial position of the rotor to be blocked and deformed, the mass center of the rotor is changed, and the rotor can be heated to generate bending vibration.

Most of the main shaft bending generated by heating is elastic deformation, the main shaft bending can be recovered to the original state through long-time turning, but the bending state of part of the rotor can not be well recovered, but the bending change of the following property can be generated along with the change of the thermal state of the rotor, and the operation monitoring parameters are reflected to be obvious changes along with the change of parameters such as rotor vibration, group load, steam temperature and the like. For the vibration, generally called thermal unbalance vibration, for the vibration, it cannot be effectively solved through general dynamic balance processing, and there may be a possibility that vibration under a certain working condition is reduced, and vibration under another working condition is increased.

Chinese patent publication No. CN 102564698A discloses a multi-rotor combined vibration mode balancing method for a single-support shafting steam turbine generator unit. At present, when single-support shafting supercritical steam turbine generator unit field dynamic balance processing is carried out, vibration information at two ends of a rotor is lacked, shaft vibration is mutually fused and influenced, and certain difficulty is brought to the field dynamic balance processing of shafting. According to the application, shaft amplitude values and phases of rotors of a shafting under critical rotating speeds and working rotating speeds are calculated through vibration vectors and vibration mode harmonic components, the characteristics of a single-support shafting structure are combined, judgment and calculation are made on unbalanced types of the shafting, combined vibration modes of multiple rotors are identified, weighting schemes of planes are directly obtained according to lag angles, mass response coefficients and first weighting intervals, and a group of weighting is adopted to be added to the related planes once. The patent application obviously improves the balance efficiency and precision of the single-support shafting rotor. However, the patent application is not suitable for a thermal unbalance vibration scene, and there is a possibility that vibration under a certain working condition is reduced and vibration under another working condition is increased, so that balance is difficult to achieve.

Disclosure of Invention

The technical problem to be solved by the invention is that the vibration balance method in the prior art is not suitable for a thermal unbalance vibration scene, and the problem that the vibration under a certain working condition is reduced, so that the vibration under another working condition is increased, and the balance is difficult to realize can be solved.

The invention solves the technical problems through the following technical means: a dynamic balancing method of stabilizing thermally unbalanced vibrations for a rotor, the method comprising:

the method comprises the following steps: erecting a data acquisition analyzer with a phase analysis function on a steam turbine generator unit;

step two: in the process of the steam turbine generator unit rotating, the shaft vibration data of the bearing bush is measured through the data acquisition analyzer, and the vibration vector before weighting is recordedAnd a phase angle α;

step three: determining a trial weighting angle theta according to the phase angle alpha, wherein the trial weighting angle represents a weighting angle in the test process;

step four: weighting the turbo generator set by using the trial weighting angle, and determining a dynamic balance influence coefficient according to vibration vectors before and after weighting and a preset initial trial weighting vector;

step five: establishing a relation among a vibration vector, a dynamic balance influence coefficient and a vector to be weighted under different working conditions of the steam turbine generator unit;

step six: and obtaining the vector to be weighted by adopting a least square method, so that the residual vibration vector of the steam turbine generator unit under each working condition is minimum.

The method uses the trial weighting angle to weight the turbo generator unit, determines the dynamic balance influence coefficient according to the vibration vectors before and after weighting and the preset initial trial weighting vector, establishes the relation among the vibration vectors, the dynamic balance influence coefficient and the vector to be weighted under different working conditions of the turbo generator unit, obtains the vector to be weighted by adopting the least square method, minimizes the residual vibration vector under each working condition of the turbo generator unit, is suitable for the thermal unbalance vibration scene, minimizes the residual vibration vector under each working condition of the turbo generator unit by the finally obtained vector to be weighted, has no possibility of reducing the vibration under a certain working condition to cause the vibration of another working condition to rise, and can realize balance.

Further, the third step includes:

and acquiring a trial weighting angle by using a formula theta which is alpha + beta-180-gamma, wherein beta is an included angle between a key phase probe and a shaft vibration probe of the steam turbine generator unit, and gamma is a mechanical lag angle.

Furthermore, the key phase probe has a positive rotation direction after the shaft vibration probe, and otherwise, the key phase probe has a negative rotation direction.

Furthermore, the mechanical lag angle is determined according to the relation between the dynamic balance rotating speed and the critical rotating speed, the balance rotating speed is lower than the critical rotating speed and forms an acute angle, and the balance rotating speed is higher than the critical rotating speed and forms an obtuse angle.

Further, the fourth step includes:

according to the vibration vectors before and after weighting and the preset initial trial weighting vector, using a formulaDetermining a dynamic balance impact coefficient, wherein,in order to obtain a weighted vibration vector,is a preset initial trial weight vector.

Further, the fifth step includes:

in the process of loading the turbonator set, measuring the shaft vibration data under different working condition loads, and respectively recording the shaft vibration data as a sequence

The corresponding load vibration vectors after the load is weighted under different working condition loads are as follows:

wherein the content of the first and second substances,representing the vector to be emphasized.

Further, the different operating condition loads represent the load from no load to full load.

Furthermore, the data acquisition analyzer with the phase analysis function is a phase analyzer.

The present invention also provides a dynamic balancing apparatus for stabilizing thermally unbalanced vibrations of a rotor, the apparatus comprising:

the acquisition module is used for erecting a data acquisition analyzer with a phase analysis function on the steam turbine generator unit;

the measuring module is used for measuring the shaft vibration data of the bearing bush through the data acquisition analyzer in the process of the rotation of the steam turbine generator unit and recording the vibration vector before weightingAnd a phase angle α;

the trial weighting angle acquisition module is used for determining a trial weighting angle theta according to the phase angle alpha, and the trial weighting angle represents a weighting angle in the test process;

the dynamic balance influence coefficient acquisition module is used for weighting the steam turbine generator unit by using the trial weighting angle and determining a dynamic balance influence coefficient according to vibration vectors before and after weighting and a preset initial trial weighting vector;

the relation building module is used for building the relation among the vibration vector, the dynamic balance influence coefficient and the vector to be weighted under different working conditions of the steam turbine generator unit;

and the control module is used for acquiring the vector to be weighted by adopting a least square method so that the residual vibration vector of the steam turbine generator unit under each working condition is minimum.

Further, the trial weighting angle obtaining module is further configured to:

and acquiring a trial weighting angle by using a formula theta which is alpha + beta-180-gamma, wherein beta is an included angle between a key phase probe and a shaft vibration probe of the steam turbine generator unit, and gamma is a mechanical lag angle.

Furthermore, the key phase probe has a positive rotation direction after the shaft vibration probe, and otherwise, the key phase probe has a negative rotation direction.

Furthermore, the mechanical lag angle is determined according to the relation between the dynamic balance rotating speed and the critical rotating speed, the balance rotating speed is lower than the critical rotating speed and forms an acute angle, and the balance rotating speed is higher than the critical rotating speed and forms an obtuse angle.

Further, the dynamic balance influence coefficient obtaining module is further configured to:

according to the vibration vectors before and after weighting and the preset initial trial weighting vector, using a formulaDetermining a dynamic balance impact coefficient, wherein,in order to obtain a weighted vibration vector,is a preset initial trial weight vector.

Further, the relationship building module is further configured to:

in the process of loading the turbonator set, measuring the shaft vibration data under different working condition loads, and respectively recording the shaft vibration data as a sequence

The corresponding load vibration vectors after the load is weighted under different working condition loads are as follows:

wherein the content of the first and second substances,representing the vector to be emphasized.

Further, the different operating condition loads represent the load from no load to full load.

Furthermore, the data acquisition analyzer with the phase analysis function is a phase analyzer.

The invention has the advantages that: the method uses the trial weighting angle to weight the turbo generator unit, determines the dynamic balance influence coefficient according to the vibration vectors before and after weighting and the preset initial trial weighting vector, establishes the relation among the vibration vectors, the dynamic balance influence coefficient and the vector to be weighted under different working conditions of the turbo generator unit, obtains the vector to be weighted by adopting the least square method, minimizes the residual vibration vector under each working condition of the turbo generator unit, is suitable for the thermal unbalance vibration scene, minimizes the residual vibration vector under each working condition of the turbo generator unit by the finally obtained vector to be weighted, has no possibility of reducing the vibration under a certain working condition to cause the vibration of another working condition to rise, and can realize balance.

Drawings

Fig. 1 is a flowchart of a dynamic balancing method for stabilizing thermally unbalanced vibrations of a rotor according to an embodiment of the present invention.

Detailed Description

In order to make the objects, 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 below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

As shown in fig. 1, a dynamic balancing method for stabilizing thermally unbalanced vibrations of a rotor, the method comprising:

s1: erecting a data acquisition analyzer with a phase analysis function on a steam turbine generator unit; the step is mainly to erect test equipment, shaft vibration data needed in subsequent tests are acquired through the data acquisition analyzer, shaft vibration of the turbogenerator set is read from a host TSI clamping piece buffer output terminal row of the data acquisition analyzer, the data acquisition analyzer with the phase analysis function is a phase analyzer, and also can be a phase analysis function integrated in other equipment, such as a vibration analyzer, specific model selection is not repeated herein, and the data acquisition analyzer can be selected according to needs in practical application.

S2: in the process of the steam turbine generator unit rotating, the shaft vibration data of the bearing bush is measured through the data acquisition analyzer, and the vibration vector before weighting is recordedAnd a phase angle α;

s3: determining a trial weighting angle theta according to the phase angle alpha, wherein the trial weighting angle represents a weighting angle in the test process; the specific process is as follows:

and acquiring a trial weighting angle by using a formula theta which is alpha + beta-180-gamma, wherein beta is an included angle between a key phase probe and a shaft vibration probe of the steam turbine generator unit, and gamma is a mechanical lag angle.

And after the key phase probe is axially vibrated, the rotation direction of the key phase probe is positive, otherwise, the rotation direction of the key phase probe is negative.

The mechanical lag angle is determined according to the relation between the dynamic balance rotating speed and the critical rotating speed, the balance rotating speed is lower than the critical rotating speed and forms an acute angle, and the balance rotating speed is higher than the critical rotating speed and forms an obtuse angle.

S4: weighting the turbo generator set by using the trial weighting angle, and determining a dynamic balance influence coefficient according to vibration vectors before and after weighting and a preset initial trial weighting vector; the specific process is as follows:

according to the vibration vectors before and after weighting and the preset initial trial weighting vector, using a formulaDetermining a dynamic balance impact coefficient, wherein,in order to obtain a weighted vibration vector,is a preset initial trial weight vector.

S5: establishing a relation among a vibration vector, a dynamic balance influence coefficient and a vector to be weighted under different working conditions of the steam turbine generator unit; the specific process is as follows:

in the process of loading the turbonator set, measuring the shaft vibration data under different working condition loads, and respectively recording the shaft vibration data as a sequence

The corresponding load vibration vectors after the load is weighted under different working condition loads are as follows:

wherein the content of the first and second substances,representing the vector to be emphasized.

The different operating condition loads represent the load from no load to full load.

S6: obtaining the vector to be weighted by adopting a least square method, so that the residual vibration vector under each working condition of the steam turbine generator unit is minimum, namelyThe minimum of each element in the vector does not reduce the vibration under a certain working condition after the vector to be weighted obtained by solving is used for weightingLeading to an increased likelihood of vibration in another operating condition.

The method provided by the invention is a dynamic balance method for comprehensively treating cold and hot vibration of a rotor with hot bending, and comprises the steps of cold and hot vibration measurement, analysis and selection of measurement data, vibration data processing and calculation, dynamic balance weighting and the like. The method has a good balance effect on stable thermal unbalance of the rotor, has multi-working-condition vibration coupling balance, and comprehensively treats the practical application value of shafting vibration.

Example 2

Based on embodiment 1 of the present invention, embodiment 2 of the present invention further provides a dynamic balance apparatus for stabilizing thermally unbalanced vibration of a rotor, the apparatus including:

the acquisition module is used for erecting a data acquisition analyzer with a phase analysis function on the steam turbine generator unit;

the measuring module is used for measuring the shaft vibration data of the bearing bush through the data acquisition analyzer in the process of the rotation of the steam turbine generator unit and recording the vibration vector before weightingAnd a phase angle α;

the trial weighting angle acquisition module is used for determining a trial weighting angle theta according to the phase angle alpha, and the trial weighting angle represents a weighting angle in the test process;

the dynamic balance influence coefficient acquisition module is used for weighting the steam turbine generator unit by using the trial weighting angle and determining a dynamic balance influence coefficient according to vibration vectors before and after weighting and a preset initial trial weighting vector;

the relation building module is used for building the relation among the vibration vector, the dynamic balance influence coefficient and the vector to be weighted under different working conditions of the steam turbine generator unit;

and the control module is used for acquiring the vector to be weighted by adopting a least square method so that the residual vibration vector of the steam turbine generator unit under each working condition is minimum.

Specifically, the trial weighting angle obtaining module is further configured to:

and acquiring a trial weighting angle by using a formula theta which is alpha + beta-180-gamma, wherein beta is an included angle between a key phase probe and a shaft vibration probe of the steam turbine generator unit, and gamma is a mechanical lag angle.

More specifically, the key phase probe has a positive rotation direction after the shaft vibration probe, and has a negative rotation direction after the shaft vibration probe is rotated.

More specifically, the mechanical lag angle is determined according to the relation between the dynamic balance rotating speed and the critical rotating speed, the balance rotating speed is lower than the critical rotating speed and forms an acute angle, and the balance rotating speed is higher than the critical rotating speed and forms an obtuse angle.

Specifically, the dynamic balance influence coefficient obtaining module is further configured to:

according to the vibration vectors before and after weighting and the preset initial trial weighting vector, using a formulaDetermining a dynamic balance impact coefficient, wherein,in order to obtain a weighted vibration vector,is a preset initial trial weight vector.

Specifically, the relationship building module is further configured to:

in the process of loading the turbonator set, measuring the shaft vibration data under different working condition loads, and respectively recording the shaft vibration data as a sequence

The corresponding load vibration vectors after the load is weighted under different working condition loads are as follows:

wherein the content of the first and second substances,representing the vector to be emphasized.

More specifically, the different operating condition loads represent the load from no load to full load.

Specifically, the data acquisition analyzer with the phase analysis function is a phase analyzer.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.