A rotor stability control device and method with ball joint

Abstract

The application discloses a rotor stability control device and method with a spherical hinge, which mainly comprises a measurer, a controller, an electromagnetic actuator and a spherical hinge bearing support. The method mainly comprises the following steps: real-time monitoring and acquisition of vibration state data of a spherical hinge balance disc during rotation of a rotor; generation of a control signal by the controller according to the monitored and acquired vibration state data; output of an electromagnetic force by the electromagnetic actuator according to the control signal; application of the electromagnetic force to the spherical hinge balance disc, suppression of vibration of the balance disc and adjustment of equivalent angular stiffness, angular damping and angular mass of the spherical hinge bearing support; and application of the equivalent angular stiffness, the angular damping and the angular mass to the rotor through a controllable flexible foundation, so as to realize rotor stability control.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of rotor stability control, in particular to a rotor stability control device and method with spherical hinge. BACKGROUND

[0002] As a kind of general machinery, centrifugal separator and compressor are typical rotating machinery, which are widely used in nuclear energy, petrochemical, metallurgy, food, textile and other fields, and their stable operation is very important. As the core component of rotating machinery, the rotor is in a high speed state when working, and abnormal vibration and system instability of the rotor may be caused by unbalanced mass, liquid-solid coupling vibration and other factors. Abnormal vibration at high speed may bring a series of serious consequences such as noise, wear and tear, shaft rupture, which seriously restricts the working effect and operation safety of rotating machinery.

[0003] At present, the essence of rotor system vibration control is the regulation and control of the three aspects of "mass-damping-stiffness". The advantages of active electromagnetic actuators, such as non-contact support, high speed range, low power consumption, no need for lubrication, make them the main technical approach for active adjustment of rotor system parameters. The commonly used radial electromagnetic actuators have many defects in use: rotor vibration may have rubbing phenomenon; electromagnetic actuators can often be installed only at the non-driving end, and the installation conditions are difficult to guarantee; the structure of the rotor system may need to be modified, which is inconvenient for testing; vibration displacement data can often be measured only through eddy current sensors; vibration acceleration can not be measured through acceleration sensors due to the rotating working condition; stiffness control strategy based on displacement feedback and damping control strategy based on speed feedback can often be carried out. SUMMARY

[0004] Based on the above problems, the present application discloses a rotor stability control device and method with spherical hinge, which can apply equivalent angular stiffness, angular damping and angular mass to the rotor to control the rotor stability and prevent accidents caused by excessive rotor vibration.

[0005] In a first aspect, a rotor stability control method with spherical hinge is provided, which is used in a vibration control system composed of a measuring device, a controller, an electromagnetic actuator and a spherical hinge bearing support connected in sequence, and specifically includes:

[0006] Real-time monitoring of vibration state data of the spherical hinge balance disc during rotation of the rotor;

[0007] According to the detected vibration state data, corresponding control signals are calculated and generated;

[0008] The control signals are input to the electromagnetic actuator to output electromagnetic force acting on the spherical hinge bearing support balance disc, so as to realize vibration suppression and equivalent angular stiffness, angular damping and angular mass adjustment of the spherical hinge balance disc;

[0009] The spherical hinge bearing support applies equivalent angular stiffness, angular damping and angular mass to the rotor through a controllable flexible foundation to realize rotor stability control.

[0010] In a second aspect, a rotor stability control device based on a spherical hinge electromagnetic actuator is provided, which is a stability control system composed of a measurement device, a controller, an electromagnetic actuator and a spherical hinge bearing support connected in sequence, and specifically includes:

[0011] The measurement device is configured to monitor and acquire vibration state data of the spherical hinge balance disc in real time when the rotor rotates, and provide the vibration state data to the controller.

[0012] The controller is configured to calculate and generate a control signal according to the rotor stability control method of claims 1-6 based on the vibration state data acquired from the measurement device, and transmit the control signal to the electromagnetic actuator.

[0013] The electromagnetic actuator is configured to output an electromagnetic force to the spherical hinge balance disc according to the control signal to suppress vibration of the balance disc and adjust the equivalent angular stiffness, angular damping and angular mass of the spherical hinge bearing support, and the main structure of the electromagnetic actuator is an "E-type" magnetic pole.

[0014] The spherical hinge bearing support is configured to apply equivalent angular stiffness, angular damping and angular mass to the rotor through a flexible controllable foundation to realize rotor stability control, and the spherical hinge bearing support mainly includes a spherical hinge balance disc, a spring, a spherical hinge support and a bearing.

[0015] The rotor stability control device based on the spherical hinge electromagnetic actuator has the following advantages: the vibration data of the spherical hinge balance disc when the rotor rotates is monitored, a real-time control signal is output by the controller, the electromagnetic actuator generates a corresponding control force to suppress vibration of the spherical hinge balance disc and adjust the equivalent angular stiffness, angular damping and angular mass of the spherical hinge bearing support, the spherical hinge bearing support applies equivalent angular stiffness, angular damping and angular mass to the rotor through a controllable flexible foundation to realize rotor stability control, the balance disc of the spherical hinge bearing support does not rotate but swings when the rotor rotates, the vibration displacement and acceleration of the balance disc can be directly measured by a sensor, in addition to the rotor stability control strategy based on displacement and displacement differential feedback through the spherical hinge bearing support structure, an angular mass control strategy based on acceleration feedback can also be developed, and the spherical hinge bearing support and the electromagnetic actuator can be installed at the driving end, thereby avoiding the need to modify the structure of the rotor system, the lack of installation conditions at the non-driving end of many rotating equipment, and the inconvenience of testing. BRIEF DESCRIPTION OF DRAWINGS

[0016] For more clearly showing the technical solutions of the embodiments of the present application, the technical solutions will be introduced below in conjunction with the drawings, wherein the same or similar elements will not be repeatedly marked in the drawings. It should be understood that the drawings are only for illustration, wherein the elements and components are not necessarily drawn according to the true shape and proportion, wherein:

[0017] Figure 1 A structure schematic diagram of a rotor stability control device according to an embodiment of the present application;

[0018] Figure 2 A spherical hinge structure schematic diagram according to an embodiment of the present application;

[0019] Figure 3 A "E-shaped" magnetic pole structure schematic diagram of an electromagnetic actuator installed outside a spherical hinge bearing support balance disc according to an embodiment of the present application. DETAILED DESCRIPTION

[0020] In order to make the technical solutions and advantages of the present application more easily understood, the embodiments will be described in detail below in conjunction with the drawings. The described embodiments are only some embodiments of the present application, and the components of the embodiments of the present application described herein can be configured according to different actual requirements. The drawings and embodiments of the present application are only for example and for the convenience of more clearly understanding the present application, and are not used to limit the protection scope of the present application.

[0021] The rotor will appear synchronous vibration and asynchronous vibration during operation. Taking a centrifuge as an example, it will also pass through a self-excited oscillation instability region during liquid filling, starting or stopping, so that a reasonable control method and device are needed to control the stability of the rotor. The non-contact support, high speed range, low power consumption, and no need for lubrication of the active electromagnetic actuator make it the main technical approach for rotor system vibration control. The commonly used radial electromagnetic actuator has many defects in use: there may be a rubbing phenomenon when the rotor vibration is abnormal; the electromagnetic actuator can often be installed only at the non-driving end, and the installation conditions are difficult to guarantee; the structure of the rotor system needs to be modified, and the test is not convenient; the vibration displacement data can often be measured only through the eddy current sensor; the vibration acceleration can not be measured by the acceleration sensor due to the rotating working condition; and the stiffness control strategy based on displacement feedback and the damping control strategy based on speed feedback can often be carried out.

[0022] To solve the above problems, the present application measures the vibration state data of the spherical hinge balance disc of the rotor during operation through a measuring device, generates real-time control signals according to the vibration state data through a controller, and outputs electromagnetic force to the spherical hinge balance disc according to the real-time control signals through an electromagnetic actuator, so as to change the equivalent angular stiffness, angular damping and angular mass of the spherical hinge bearing support, and apply to the rotor through a controllable flexible foundation, so as to realize the stability control of the rotor.

[0023] First, the rotor stability control device with ball hinge disclosed in the embodiment of the application is introduced. It should be noted that the control device of the present application is introduced by taking a vertical rotor system as an example, but the vertical rotor system is not a limitation on the scope of the present application, and the stability control device and method proposed in the present application can also be adjusted and used in other forms of rotating equipment rotor system.

[0024] Referring to Figure 1 The rotor stability control device provided by the embodiment of the application includes a measurer 1, a controller 2, an electromagnetic actuator 3, and a ball hinge bearing support 4.

[0025] Referring to Figure 2 The ball hinge bearing support 4 provided by the embodiment of the application includes a ball hinge balance disc 41, a ball hinge support 42, a bearing 43, and a spring 44. The remaining elements in the figure are: 31 is an electromagnetic actuator "E-shaped" magnetic pole, 5 is a rotor, and 11 is a sensor.

[0026] The measurer 1 is used to monitor and obtain the vibration data of the ball hinge balance disc 41 when the rotor 5 rotates in real time, and provide the vibration data to the controller 2.

[0027] The controller 2 is used to calculate the real-time control signal required to suppress the vibration of the ball hinge balance disc 41 and adjust the equivalent angular stiffness, angular damping, and angular mass of the ball hinge bearing support 4 according to the vibration data obtained from the measurer 1, and transmit the control signal to the electromagnetic actuator 3.

[0028] The electromagnetic actuator 3 is used to output electromagnetic force to the ball hinge balance disc 41 according to the control signal, so as to suppress the vibration of the balance disc and adjust the equivalent angular stiffness, angular damping, and angular mass of the ball hinge bearing support 4.

[0029] The ball hinge bearing support 4 applies equivalent angular stiffness, angular damping, and angular mass to the rotor 5 through a controllable flexible foundation, thereby realizing rotor stability control. The controllable flexible foundation is composed of the rotor 5, the bearing 43, and the ball hinge support 42. The ball hinge support surrounds the outside of the rotor and is connected to the rotor through the bearing. When the rotor vibrates, the bearing transmits force to the ball hinge support, causing the ball hinge balance disc to swing. Changing the electromagnetic force applied by the electromagnetic actuator to the ball hinge balance disc can adjust the equivalent angular stiffness, angular damping, and angular mass when it swings, thereby applying different equivalent angular stiffness, angular damping, and angular mass to the rotor.

[0030] In actual implementation, the measurer 1 is composed of a sensor and a signal conditioner. The sensor 11 converts the measured value into an analog signal for processing by the signal conditioner. The signal conditioner filters and denoises the analog signal output by the sensor. The vibration state data required by the controller 2 varies according to the rotor stability control strategy used, and the corresponding measurer also needs to be adjusted accordingly. In this embodiment, when the data required by the control strategy is the rotor vibration displacement, the sensor 11 used is an eddy current sensor, and the measurer is a displacement measurer; when the required data is the vibration acceleration data, the sensor 11 used is an acceleration sensor, and the measurer is an acceleration measurer.

[0031] The controller 2 is a high-efficiency controller based on FPGA, which can process the vibration data obtained by the measurer in real time at a very high rate. By using the equivalent angular stiffness, angular damping, and angular mass control strategies, the corresponding control signals are generated in the form of voltage and output to the electromagnetic actuator 3.

[0032] The electromagnetic actuator 3 is composed of two parts: a converter and an actuator. The converter amplifies the control signal to obtain enough energy to drive the electromagnetic actuator to generate electromagnetic force; at the same time, in order to avoid the existence of inductive load which makes the control signal lag, the voltage signal is converted into a current signal.

[0033] Referring to FIGS. 1, 2, and 3, Figure 2 and Figure 3 As shown, the main component of the actuator is a "E-shaped" magnetic pole 31, which is composed of a main magnetic pole 311 and two auxiliary magnetic poles 312; the actuator works based on the principle of electromagnetic conversion, and when current is passed through the coil of the "E-shaped" magnetic pole, electromagnetic force is generated and applied to the surface of the spherical hinge balance disc 41. A plurality of "E-shaped" magnetic poles are combined in pairs and arranged to be installed on the upper and lower sides of the four controlled force positions of the spherical hinge balance disc. For the convenience of subsequent description, the controlled force positions of the spherical hinge balance disc are referred to as force points. The four force points are evenly distributed on the surface of the spherical hinge balance disc and are used to control the swing of the spherical hinge balance disc in front, back, left, and right directions.

[0034] Due to the influence of the controllable flexible foundation structure, when the rotor 5 rotates and vibrates, the spherical hinge support balance disc 41 will swing. According to the vibration state of the balance disc when it swings, the electromagnetic force applied to the surface of the balance disc by the actuator changes, and through different control strategies of the controller 2: equivalent angular stiffness control strategy, angular damping control strategy, and angular mass control strategy, the equivalent angular stiffness, equivalent angular damping, and equivalent angular mass are applied to the rotor to control the vibration of the balance disc and the stability of the rotor.

[0035] Based on the inventive concept, the application also provides a rotor stability control method corresponding to the above-mentioned rotor stability control device.

[0036] The rotor system instability is embodied in rotor vibration. In the embodiment of the application, the vibration measuring plane is the spherical hinge balance disc 41, and when the rotor 5 rotates, the vibration of the balance disc 41 is embodied in forward and backward swinging, and the vibration state data to be measured is the vibration displacement and acceleration in the up and down direction. The measuring points are arranged close to the force points. When the vibration displacement is monitored, the probe of the displacement sensor 11 is perpendicular to the surface of the balance disc, and the monitored displacement data is the vibration displacement of the two measuring points in the up and down direction when the balance disc swings; when the vibration acceleration is monitored, the probe of the sensor 11 is fixed on the surface of the balance disc, and the monitored displacement data is the acceleration of the two measuring points when the balance disc swings. When the balance disc is in static balance, the displacement is recorded as (0, 0), and when the vibration is generated, the vibration displacement measured by the sensor is recorded as (x, y); the vibration acceleration is recorded as The vibration velocity is obtained by differentiating the displacement data, and is recorded as

[0037] When the vibration is controlled by the electromagnetic actuator, the balance disc 41 is subjected to the electromagnetic force generated by the "E-shaped" magnetic pole 31 of the electromagnetic actuator and the elastic force of the supporting spring 44, and the control forces f x 、f y in the x and y directions satisfy the following formula (1):

[0038]

[0039] wherein K ix 、K iy are the current stiffness of the electromagnetic actuator in the x and y directions respectively; K sx 、K sy are the displacement stiffness of the electromagnetic actuator in the x and y directions respectively; i x 、i y are the disturbance parts of the control current of the electromagnetic actuator in the two directions, which are simply referred to as disturbance current.

[0040] K ix 、K iy 、K sx 、K sy satisfy the following formula (2):

[0041]

[0042] wherein k1, k2, k3 and k4 are the inherent properties of the magnetic pole of the electromagnetic actuator, which are known constants; K l is the spring stiffness, which is a known constant; g is the air gap thickness between the magnetic pole and the spherical hinge balance disc, which is a known constant; I b is the direct current bias part of the control current of the electromagnetic actuator, which is simply referred to as bias current, and is the property of the electromagnetic actuator itself;

[0043] The control forces f x 、f yThe equivalent angular stiffness K of the spherical hinge θx , K θy The equivalent angular damping D θx , D θy The equivalent angular mass M θx , M θy The relationship between the applied disturbance current i x , i y respectively satisfies the following formula (3), formula (4), formula (5):

[0044]

[0045]

[0046]

[0047] In the formula, L is the distance between the center of the spherical hinge balance disc and the force point.

[0048] From the vibration feedback control scheme, the applied disturbance current i x and i y in the x and y directions satisfy the following formula (6):

[0049]

[0050] Where q c1 , q c2 are the reverse cross stiffness coefficients; K is the equivalent displacement stiffness output value of the electromagnetic actuator, d c is the equivalent damping output value of the electromagnetic actuator, and m c is the equivalent mass output value of the electromagnetic actuator.

[0051] When the angular stiffness control strategy based on displacement feedback is adopted, the damping control force and the mass control force are ignored, the spherical hinge bearing support applies equivalent angular stiffness to the rotor system, and the disturbance current satisfies the following formula (7):

[0052]

[0053] Substituting formula (3) can obtain the equivalent angular stiffness:

[0054]

[0055] When the angular damping control strategy based on displacement differential feedback is adopted, the stiffness control force and the mass control force are ignored, the spherical hinge bearing support applies equivalent angular damping to the rotor system, and the disturbance current satisfies the following formula (9):

[0056]

[0057] Substituting formula (4) can obtain the equivalent angular damping:

[0058] Dθx = D θy = -2L 2 d c (10)

[0059] When the angular mass control strategy based on acceleration feedback is adopted, the stiffness control force and the damping control force are ignored, the spherical hinge bearing support applies equivalent angular mass to the rotor system, and the disturbance current satisfies the following formula (11):

[0060]

[0061] The equivalent angular mass can be obtained by substituting formula (5) into formula (11):

[0062] M θx = M θy = -2L 2 m c (12)

[0063] Since the control voltage output by the controller needs to be converted into a control current by a converter, the x and y direction disturbance currents i x , i y of the electromagnetic actuator and the x and y direction control voltages u x , u y output by the controller satisfy the following formula (13), where a is a current-voltage linearization value, and is an inherent property of the electromagnetic actuator, which is a known quantity.

[0064]

[0065] The coil control current of the electromagnetic actuator is in a differential input mode, and the control current I is composed of a bias current I b and a disturbance current i. Therefore, the control current I x+ , I x- , I y+ , I y- of the electromagnetic actuator and the bias current I b and the control voltage u x , u y output by the controller satisfy the following formula (14):

[0066]

[0067] In the above formula (14), the bias current I b is a known quantity.

[0068] Substituting formula (13) into formula (7), formula (9), and formula (11), it can be obtained that the control voltage values output by the controller to the electromagnetic actuator when adjusting the equivalent angular stiffness, angular damping, and angular mass satisfy formula (15), (16), and (17), respectively:

[0069]

[0070]

[0071]

[0072] The above is a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and those skilled in the art can make appropriate adjustments without departing from the principles of the present application, and these adjustments shall be included in the protection scope of the present application.

Claims

1. A method for controlling rotor stability with a spherical hinge, which is used in a control device consisting of a measurer, a controller, an electromagnetic actuator, and a spherical hinge bearing support, characterized in that: The method comprises: Real-time monitoring of vibration state data of the spherical hinge balance disc during rotation of the rotor; Generating a control signal based on the monitored vibration state data; The electromagnetic actuator outputs an electromagnetic force according to the control signal, and applies the electromagnetic force to the spherical hinge balance disc to suppress vibration of the balance disc and adjust the equivalent angular stiffness, angular damping, and angular mass of the spherical hinge bearing support; The equivalent angular stiffness, angular damping, and angular mass are applied to the rotor through a controllable flexible foundation to achieve rotor stability control; the controllable flexible foundation is composed of the rotor, the bearing, and the spherical hinge support; the spherical hinge support surrounds the outside of the rotor and is connected to the rotor through the bearing; The control signal includes: x-axis, y-axis direction control voltage signal u x , u y , and the spherical hinge bearing support is used to apply equivalent angular stiffness, angular damping and angular mass to the rotor by three feedback control strategies for rotor stability control; the three feedback control strategies include: 1) Angular stiffness control strategy based on displacement feedback; 2) Angular damping control strategy based on displacement differential feedback; 3) Angular mass control strategy based on acceleration feedback; When the angular stiffness control strategy based on displacement feedback is used, the equivalent angular stiffness of the spherical hinge bearing support is changed by controlling the force to suppress vibration of the balance disc and control the rotor stability; The control voltage signal u x , u y satisfies equation (1): wherein a is a current-voltage linearization value; K sx , K sy are the displacement stiffness of the electromagnetic actuator in the x-axis and y-axis directions, respectively; x, y are the vibration displacement of the spherical hinge balance disc in the x-axis and y-axis directions, respectively; K ix , K iy are the current stiffness of the electromagnetic actuator in the x-axis and y-axis directions, respectively; q c1 , q c2 are the inverse cross stiffness coefficients; K is the equivalent displacement stiffness output value of the electromagnetic actuator; where K sx , K sy satisfies the following equation (2): K ix , K iy satisfies the following equation (3): In the above formula (1) and (2), k1, k2, k3, k4 are electromagnetic actuator magnetic pole inherent properties; K l is the spring stiffness; g is the air gap thickness between the magnetic pole and the ball hinge balance disc; I b is the electromagnetic actuator bias current; i x , i y are respectively the electromagnetic actuator disturbance currents in two directions; The spherical hinge exerts an angular stiffness K on the rotor θx , K θy satisfies equation (4): Where L is the distance between the center of the spherical hinge balance disc and the force point of the electromagnetic force; When the angular damping control strategy based on displacement differential feedback is used, the equivalent angular damping of the spherical hinge bearing support is changed by controlling the force to suppress vibration of the balance disc and control the rotor stability; The control voltage signal u x , u y satisfies equation (5): wherein d c is the equivalent damping output value of the electromagnetic actuator, is the vibration displacement differential value of the spherical hinge balance disc in the x-axis and y-axis directions, i.e., the speed; The spherical hinge exerts an angular damping D on the rotor θx , D θy satisfies equation (6): D θx = D θy = -2L 2 d c (6) When the angular mass control strategy based on acceleration feedback is used, the equivalent angular mass of the spherical hinge bearing support is changed by controlling the force to suppress vibration of the balance disc and control the rotor stability; The control voltage signal u x , u y satisfies equation (7): wherein m c is the equivalent mass output value of the electromagnetic actuator, is the vibration acceleration of the spherical hinge balance disc in the x-axis and y-axis directions; The spherical hinge applies an angular mass M to the rotor θx , M θy satisfies equation (8): M θx = M θy = -2L 2 m c (8).

2. The stability control method according to claim 1, characterized by, During rotation of the rotor, the monitored balance disc of the spherical hinge bearing support does not rotate but swings; the monitored vibration state data includes vibration displacement and acceleration when the balance disc swings, and does not directly monitor radial or axial vibration of the rotor.

3. A rotor stability control device characterized by comprising: It comprises a measurer, a controller, an electromagnetic actuator, and a spherical hinge bearing support; The measurer is used to monitor vibration data of the spherical hinge balance disc during rotation of the rotor in real time and provide the vibration data to the controller; The controller is used to output a control signal to the electromagnetic actuator according to the rotor stability control method of any one of claims 1-2; The electromagnetic actuator is used to output an electromagnetic force to the spherical hinge balance disc according to the control signal to suppress vibration of the spherical hinge balance disc and adjust the equivalent angular stiffness, angular damping, and angular mass of the spherical hinge bearing support; The spherical hinge bearing support applies the equivalent angular stiffness, angular damping, and angular mass to the rotor through a controllable flexible foundation to achieve rotor stability control.

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