A phase modulator body structure active regulation method and system

Abstract

The present application relates to the technical field of phase modifier operation maintenance, in particular to a kind of phase modifier body structure active regulation method and system.The phase modifier body structure active regulation method includes the following steps: collecting phase modifier stator current signal, and based on electromagnetic vibration decoupling model, the stator core radial effective vibration displacement amplitude is calculated;Based on the mechanical model of laminated equivalent simply supported beam, the stator core radial effective vibration displacement amplitude is converted into the alternating bending stress amplitude of stator core lamination;Combining the revised Miner fatigue cumulative damage theory, the alternating bending stress amplitude is used to calculate the fatigue life loss rate of stator core per unit time;With the rated allowable life loss rate per unit time as control target, the target control temperature of stator core is obtained by inversion, and then the target regulation flow of cooling medium is calculated and output through heat transfer coupling model, to actively regulate core temperature and fatigue life.

Description

Technical Field

[0001] This invention relates to the field of synchronous condenser operation and maintenance technology, specifically to a method and system for active control of the synchronous condenser body structure. Background Technology

[0002] As an important dynamic regulation device for power grids, synchronous condensers operate under complex electromagnetic excitation and mechanical vibration coupling conditions for a long time. Their stator core lamination structure is prone to cumulative fatigue damage, which can lead to problems such as structural loosening, increased vibration, and even insulation failure.

[0003] Existing technologies mainly focus on the electrical performance adjustment of synchronous condensers and the control of reactive power and voltage support, with limited research on the mechanical vibration, alternating stress, and fatigue life evolution of stator cores caused by electromagnetic excitation. Furthermore, existing fatigue calculations often employ general material models, failing to consider the unique electromagnetic excitation characteristics of synchronous condensers, the coupling effect of laminated structures, and the influence of operating temperature. This results in insufficient calculation accuracy, inability to quantify life loss in real time, and difficulty in achieving proactive preventative control. Moreover, some solutions are not fully disclosed, exhibiting issues such as ambiguous parameter definitions, inconsistent dimensions, and incomplete derivation logic, which can easily lead to insufficient disclosure during patent examination. Summary of the Invention

[0004] The purpose of this invention is to provide an active control method for the structure of a camera condenser, so as to solve the problem that it is difficult for camera condensers to achieve active preventive control in the prior art.

[0005] To address the aforementioned problems, this invention proposes an active control method for the structure of a camera condenser. The technical solution adopted is as follows: A method for actively controlling the structure of a camera body includes the following steps: S1. Acquire the stator current signal of the synchronous condenser, and calculate the effective radial vibration displacement amplitude of the stator core based on the electromagnetic vibration decoupling model. S2. Based on the mechanical model of the equivalent simply supported beam of the stator core, the effective radial vibration displacement amplitude of the stator core is converted into the alternating bending stress amplitude of the stator core laminations. S3. Based on the modified Miner fatigue cumulative damage theory, calculate the stator core fatigue life loss rate per unit time according to the alternating bending stress amplitude. S4. Based on the stator core fatigue life loss rate per unit time, and using the rated allowable fatigue life loss rate per unit time as the control target, the target control temperature of the stator core is obtained by inversion; the target regulation of the cooling medium is calculated through a heat transfer coupling model. This allows for proactive control of stator core temperature and fatigue life.

[0006] Further, in step S1, the formula for calculating the effective radial vibration displacement amplitude of the stator core is:

[0007] in, This refers to the effective radial vibration displacement amplitude of the stator core. This is the vibration decoupling correction factor; This refers to the effective radial force-bearing area of ​​the stator core; For the first Secondary stator current harmonic magnetomotive force weighting coefficient; For the first Secondary stator current harmonic amplitude; The vacuum permeability; This is the equivalent radial stiffness of the stator core; It is the ratio of the excitation frequency to the natural frequency of the iron core; The damping ratio of the stator core structure.

[0008] Furthermore, the aforementioned The sample was obtained by harmonic decomposition after sampling from a current transformer; The data was obtained through a synchronous vibration test of the synchronous condenser under no-load conditions and calibration with current synchronization.

[0009] Further, in step S2, the formula for calculating the alternating bending stress amplitude of the stator core laminations is:

[0010] in, The amplitude of alternating bending stress in the stator core laminations; This is the correction factor for lamination coupling; The elastic modulus of the core lamination material; The thickness of a single sheet of iron core lamination; This refers to the effective radial vibration displacement amplitude of the stator core. The span is the equivalent simply supported beam span of the laminated beam.

[0011] Furthermore, based on the modified Miner fatigue cumulative damage theory, the stator core fatigue life loss rate per unit time is calculated according to the alternating bending stress amplitude, specifically including: Based on the modified Miner fatigue cumulative damage theory, and taking into account the alternating bending stress amplitude and the real-time operating temperature of the core, the stress ratio correction coefficient and the temperature fatigue degradation coefficient are introduced to calculate the fatigue life loss rate of the stator core per unit time.

[0012] Furthermore, the formula for calculating the fatigue life loss rate of the stator core per unit time is as follows: in, The fatigue life loss rate of the stator core per unit time; This is the stress ratio correction factor; This is the coefficient of temperature fatigue degradation; The frequency of the alternating stress cycle; This represents the amplitude of alternating bending stress in the iron core laminations. , For core material S N is the characteristic constant of the fatigue curve. Furthermore, the formula for calculating the target control temperature of the stator core is:

[0013] in, Stator core target control temperature; Rated permissible lifespan loss rate per unit time; Reference temperature; Temperature influence coefficient; This is the stress ratio correction factor; The frequency of the alternating stress cycle; This represents the amplitude of alternating bending stress in the iron core laminations. , For core material S N is the characteristic constant of the fatigue curve.

[0014] Furthermore, the target controlled flow rate of the cooling medium is calculated in segments, and the calculation formula is as follows:

[0015] in, Cooling medium target flow rate regulation; , Maximum and minimum safe flow rates of the cooling system; : Inlet temperature of cooling medium; The maximum allowable operating temperature of the iron core; Heat generated by stator core losses; Heat transfer ratio coefficient; Effective heat exchange area; Stator core target control temperature.

[0016] Furthermore, the step of calculating the target flow rate of the cooling medium through a heat transfer coupling model to actively regulate the stator core temperature and fatigue life includes: The target flow rate of the cooling medium is calculated by a heat transfer coupling model, and the target flow rate is sent to the actuator of the cooling system to realize closed-loop regulation of the target flow rate of the cooling medium, control the temperature of the stator core and the fatigue wear rate, and complete the active regulation of the synchronous condenser body structure.

[0017] The present invention also provides a system for performing the above-described active control method for the camera body structure, comprising: The effective vibration displacement amplitude acquisition module is used to collect the stator current signal of the synchronous condenser and calculate the effective radial vibration displacement amplitude of the stator core based on the electromagnetic vibration decoupling model. The alternating bending stress amplitude acquisition module is used to convert the effective radial vibration displacement amplitude of the stator core into the alternating bending stress amplitude of the stator core laminations based on the mechanical model of the equivalent simply supported beam of the laminated laminations. The fatigue life loss rate acquisition module is used to calculate the fatigue life loss rate of the stator core per unit time based on the alternating bending stress amplitude, according to the modified Miner fatigue cumulative damage theory. The active control module is used to obtain the target control temperature of the stator core based on the fatigue life loss rate of the stator core per unit time and the rated allowable fatigue life loss rate per unit time. It calculates the target control flow rate of the cooling medium through a heat transfer coupling model to actively control the temperature and fatigue life of the stator core.

[0018] Compared with the prior art, the present invention has the following significant advantages: This invention provides a method for health monitoring and active control of synchronous condenser stator structure based on the coupled calculation of vibration characteristics, alternating stress, and fatigue life. By establishing a four-stage interlocking calculation model—electromagnetic vibration decoupling, alternating stress calculation, fatigue life loss rate calculation, and active cooling flow control—it achieves accurate characterization and closed-loop active control of the synchronous condenser stator core fatigue state, making it particularly suitable for the long-term safe and stable operation control of large synchronous condensers. This invention avoids the traditional reactive power and voltage control aspects of synchronous condensers, focusing instead on the fatigue safety of the core structure. It achieves full-link quantitative calculation from electrical signals, mechanical response, fatigue damage to active control, eliminating the need for numerous additional dedicated sensors and facilitating engineering implementation. The innovative introduction of correction terms such as decoupling coefficient, lamination coupling coefficient, and temperature fatigue degradation coefficient significantly improves calculation accuracy, effectively extending the service life of the synchronous condenser stator structure and enhancing equipment operational reliability. Attached Figure Description

[0019] Figure 1 A flowchart illustrating the active control method for the camera body structure of the present invention. Detailed Implementation

[0020] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] The active control method and system for the body structure of the camera converter according to embodiments of this application are described below with reference to the accompanying drawings.

[0023] The following is combined with Figure 1 This application provides a detailed description of the active control method for the camera body structure.

[0024] Step S1: Acquire the stator current signal of the phase converter and calculate the effective radial vibration displacement amplitude of the stator core based on the electromagnetic vibration decoupling model. This step achieves accurate mapping from the current signal to the effective vibration displacement of the core, eliminates irrelevant interference components, and provides a real and effective mechanical excitation input for subsequent stress calculation, solving the problem of mixed interference in traditional vibration measurements and the inability to be directly used for fatigue calculation.

[0025] Specifically, the formula for calculating the effective radial vibration displacement amplitude of the stator core is as follows:

[0026] in, This refers to the effective radial vibration displacement amplitude of the stator core. This is the vibration decoupling correction factor; This refers to the effective radial force-bearing area of ​​the stator core; For the first Secondary stator current harmonic magnetomotive force weighting coefficient; For the first Secondary stator current harmonic amplitude; The vacuum permeability; This is the equivalent radial stiffness of the stator core; It is the ratio of the excitation frequency to the natural frequency of the iron core; This represents the damping ratio of the stator core structure. Among them, It is obtained by sampling from a current transformer and then undergoing harmonic decomposition. The data was obtained through a synchronous vibration test of the synchronous condenser under no-load conditions and calibration with current synchronization.

[0027] The meanings and methods of obtaining the symbols in the formula for calculating the effective radial vibration displacement amplitude of the stator core are as follows: The effective radial vibration displacement amplitude of the stator core is the output of this formula and serves as the input for the formula in step 2. Vibration decoupling correction coefficient, dimensionless, obtained through no-load vibration test of synchronous condenser and current synchronous calibration; The effective radial force-bearing area of ​​the stator core is determined by the design dimensions of the stator core of the synchronous condenser. The weighting coefficient of the i-th stator current harmonic magnetomotive force is calculated from the stator winding short-pitch coefficient and distribution coefficient. The amplitude of the i-th stator current harmonic is obtained by harmonic decomposition after sampling through a current transformer. Vacuum permeability is a universal physical constant. The equivalent radial stiffness of the stator core was determined by actual measurement through factory modal testing. The ratio of the excitation frequency to the natural frequency of the iron core is calculated from the fundamental frequency of the power grid and the natural frequency of the iron core. The damping ratio of the stator core structure was determined through modal testing.

[0028] The source and derivation of the above formula are as follows: The original formula comes from the formula for the steady-state displacement amplitude of single-degree-of-freedom forced vibration in mechanical vibration, and its classic form is:

[0029] Where X is the amplitude of the forced vibration displacement of the structure, F0 is the amplitude of the excitation force, k is the equivalent stiffness of the structure, and r is the ratio of the excitation frequency to the natural frequency. is the structural damping ratio.

[0030] The improvement and derivation process of this invention is as follows: The radial vibration of the stator core of the synchronous condenser is mainly driven by the electromagnetic excitation force generated by the stator current harmonics. According to the electromagnetic principle of motors, the amplitude of the electromagnetic excitation force is proportional to the square of the air gap magnetic flux density, and the magnetic flux density amplitude is proportional to the combined magnetomotive force of the stator harmonic currents. Substitute the electromagnetic excitation force into the classical forced vibration displacement formula in the form of current harmonic weighted synthesis. By introducing a vibration decoupling correction coefficient η, non-electromagnetic excitation components such as frame vibration, rotor imbalance, and fluid disturbance are eliminated, and only the effective vibration components caused by current harmonics that directly lead to core fatigue are retained. The formulas were reorganized and merged to form an electromagnetic vibration decoupling calculation formula applicable to the stator core of a synchronous condenser, namely, the calculation formula for the effective radial vibration displacement amplitude of the stator core.

[0031] Step S2: Based on the mechanical model of the equivalent simply supported beam of the stator core, the effective radial vibration displacement amplitude of the stator core is converted into the alternating bending stress amplitude of the stator core laminations. This step transforms the mechanical vibration displacement into alternating bending stress that directly induces fatigue, establishes a quantitative relationship between vibration characteristics and structural damage driving forces, and provides core mechanical parameters for calculating life loss.

[0032] Specifically, the formula for calculating the amplitude of alternating bending stress in stator core laminations is as follows:

[0033] in, The amplitude of alternating bending stress in the stator core laminations; This is the correction factor for lamination coupling; The elastic modulus of the core lamination material; The thickness of a single sheet of iron core lamination; This refers to the effective radial vibration displacement amplitude of the stator core. The span is the equivalent simply supported beam span of the laminated beam.

[0034] Here, the parameters in the formula are explained in detail: The alternating bending stress amplitude of the stator core laminations is the output of this formula and serves as the input for the formula in step 3. : Lamination coupling correction coefficient, dimensionless, obtained by mechanical bending test of lamination group; The elastic modulus of the core lamination material is determined by the material's factory performance parameters; The thickness of a single iron core lamination is given by the design drawings; The formula for calculating the effective radial vibration displacement amplitude of the stator core outputs the effective radial vibration displacement amplitude of the stator core. The span of the laminated equivalent simply supported beam is determined by the dimensions of the stator core toothed yoke structure.

[0035] The source and derivation of the above formula are as follows: The original formula is derived from the formulas for normal stress and maximum deflection of simply supported beams in mechanics of materials. The classical relationship is:

[0036] Where σ is the bending stress, M is the bending moment, and y is the distance from the neutral axis of the cross section. Let the moment of inertia of the cross section be... Where E is the maximum deflection, E is the elastic modulus, and L is the beam span.

[0037] The improvement and derivation process of this invention is as follows: The single silicon steel lamination of the stator core of the phase converter is equivalent to a simply supported beam structure, and the radial vibration displacement of the core is equivalent to the maximum deflection of the simply supported beam. By combining the bending stress formula and the deflection formula, substituting the geometric parameters of the rectangular laminated section, and eliminating intermediate quantities such as bending moment and moment of inertia, a direct relationship between displacement and stress is obtained. By introducing a lamination coupling correction coefficient β and considering the influence of inter-laminated friction and constraint effects on the actual bending stress after multiple laminations are pressed together, an alternating stress calculation formula suitable for lamination structures of iron cores is formed.

[0038] Step S3: Based on the modified Miner fatigue cumulative damage theory, calculate the stator core fatigue life loss rate per unit time according to the alternating bending stress amplitude. This step quantifies the cumulative rate of core fatigue damage in real time, establishes a quantitative relationship between stress level and life loss, and provides clear control targets and decision-making basis for subsequent active regulation.

[0039] Specifically, based on the modified Miner fatigue cumulative damage theory, the fatigue life loss rate of the stator core per unit time is calculated according to the alternating bending stress amplitude, including: Based on the modified Miner fatigue cumulative damage theory, and taking into account the alternating bending stress amplitude and the real-time operating temperature of the core, the stress ratio correction coefficient and the temperature fatigue degradation coefficient are introduced to calculate the fatigue life loss rate of the stator core per unit time.

[0040] The formula for calculating the fatigue life loss rate of the stator core per unit time is: in, The fatigue life loss rate of the stator core per unit time; This is the stress ratio correction factor; This is the coefficient of temperature fatigue degradation; The frequency of the alternating stress cycle; This represents the amplitude of alternating bending stress in the iron core laminations. , For core material S N is the characteristic constant of the fatigue curve.

[0041] Here, the parameters in the formula are explained in detail: The fatigue life loss rate of the stator core per unit time is the output of this formula and is used as the input of the formula in step 4. Stress ratio correction factor, dimensionless, calibrated through material fatigue mechanics tests; Temperature fatigue degradation coefficient, dimensionless, related to the real-time operating temperature of the iron core; The alternating stress cycle frequency is determined by the power grid frequency; : Amplitude of alternating bending stress in stator core laminations; , The characteristic constants of the SN fatigue curve of the iron core material are obtained by fitting the material fatigue test.

[0042] The initial source of the formula is: The original formula is derived from Miner's linear fatigue cumulative damage criterion and the SN power function fatigue curve of metallic materials, and its classic form is:

[0043] Where D represents total fatigue damage. This represents the actual number of loops. The allowable number of cycles under this stress is given, and m and C are the material fatigue characteristic constants.

[0044] The improvement and derivation process of this invention is as follows: With the stress cycle frequency fixed under the power frequency excitation of the synchronous condenser, the expression for the fatigue damage evolution rate per unit time is obtained by differentiating the number of cycles with respect to time. A stress ratio correction factor λ(R) is introduced to compensate for the influence of asymmetric cyclic stress on fatigue life of core laminations under preload. The temperature fatigue degradation coefficient γ(T) is introduced to reflect the deteriorating effect of the increase in core operating temperature on the fatigue performance of the material. A model for fatigue life loss rate per unit time that can be calculated in real time is developed to achieve dynamic characterization of damage rate.

[0045] Step S4: Based on the stator core fatigue life loss rate per unit time, and using the rated allowable fatigue life loss rate per unit time as the control target, the target control temperature of the stator core is obtained through inversion. The target regulating flow rate of the cooling medium is calculated through a heat transfer coupling model to actively regulate the stator core temperature and fatigue life. This step transforms the abstract fatigue life loss rate into a directly executable cooling flow rate control command. By using temperature as an intermediate regulating variable, a complete closed-loop control is achieved, from "fatigue life deterioration - temperature increase - flow rate increase - temperature decrease - fatigue life stabilization," thereby actively extending the fatigue life of the synchronous condenser stator structure and ensuring safe operation.

[0046] Specifically, the target flow rate of the cooling medium is calculated using a heat transfer coupling model to actively regulate the stator core temperature and fatigue life, including: The target flow rate of the cooling medium is calculated by a heat transfer coupling model, and the target flow rate is sent to the actuator of the cooling system to realize closed-loop regulation of the target flow rate of the cooling medium, control the temperature of the stator core and the fatigue wear rate, and complete the active regulation of the synchronous condenser body structure.

[0047] The formula for calculating the target control temperature of the stator core is:

[0048] in, Stator core target control temperature; Rated permissible lifespan loss rate per unit time; Reference temperature; Temperature influence coefficient; This is the stress ratio correction factor; The frequency of the alternating stress cycle; This represents the amplitude of alternating bending stress in the iron core laminations. , For core material S N is the characteristic constant of the fatigue curve.

[0049] The target flow rate of the cooling medium is calculated in segments, and the calculation formula is as follows:

[0050] in, Cooling medium target flow rate regulation; , Maximum and minimum safe flow rates of the cooling system; : Inlet temperature of cooling medium; The maximum allowable operating temperature of the iron core; Heat generated by stator core losses; Heat transfer ratio coefficient; Effective heat exchange area; Stator core target control temperature.

[0051] Here, the parameters in the formula are explained in detail: The target control temperature of the stator core is obtained by inverting the target value of the life loss rate. Rated permissible life loss rate per unit time, determined based on the design life; Reference temperature; Temperature influence coefficient, determined by high-temperature fatigue test; The target flow rate of the cooling medium is the final output of this invention. , The maximum and minimum safe flow rates of the cooling system are determined by the design parameters of the cooling system. The inlet temperature of the cooling medium is collected in real time by a temperature sensor. The maximum allowable operating temperature of the iron core is determined by the heat resistance rating of the equipment insulation and materials. The heat generated by stator core losses is determined by design parameters and no-load tests. The heat transfer ratio coefficient is obtained through heat transfer performance testing. Effective heat exchange area is determined by the structural dimensions of the cooling system.

[0052] The source and derivation of the above formula are as follows: The original formula is derived from the fundamental formula of forced convection heat transfer and the Dittus-Boelter convective heat transfer criterion, and its classic form is:

[0053] Where Φ is the heat transfer, h is the heat transfer coefficient, A is the heat transfer area, ΔT is the temperature difference, and the Reynolds number Re is positively correlated with the flow rate of the cooling medium. Therefore, the heat transfer coefficient has an exponential relationship with the flow rate.

[0054] The improvement and derivation process of this invention is as follows: Using the rated permissible life loss rate as the control threshold, the target control temperature of the stator core required to ensure the design life is derived by inverting the formula for the fatigue life loss rate of the stator core per unit time. ; Based on the principle of forced convection heat transfer, the exponential relationship between the heat transfer coefficient and the flow rate is substituted into the heat transfer equation to derive the analytical relationship between the cooling flow rate and the core temperature. By combining the physical operating boundaries of the cooling system, upper and lower limits of flow constraints are set to form a segmented flow target calculation model; Ultimately, by adjusting the flow rate of the cooling medium to change the core temperature, the fatigue life loss rate is indirectly controlled, thus achieving closed-loop active regulation.

[0055] This invention employs four core formulas coupled sequentially, with the output of one formula directly serving as the input for the next, forming a complete closed-loop calculation chain. All parameters can be obtained through sampling, experimental calibration, and design parameters. The formulas are strictly self-consistent in terms of dimensions, and the derivation process is publicly available and complete, eliminating any technical obstacles to implementation. Specifically: 1. The formula for the effective radial vibration displacement amplitude of the stator core is derived from electrical quantities (current) and decoupled to obtain the effective mechanical vibration displacement of the core; 2. The formula for the amplitude of alternating bending stress of stator core laminations converts displacement input into alternating bending stress of the laminations, realizing electromechanical coupling conversion; 3. The formula for the fatigue life loss rate per unit time of the stator core uses stress as input to calculate the real-time fatigue life loss rate and establish a damage quantification model; 4. The formulas for target control temperature and target flow rate of cooling medium are based on the life loss rate as the control target. The temperature is then calculated and the cooling flow rate is determined to complete the active control execution.

[0056] All formulas are strictly self-consistent in dimensions, and all parameters can be clearly obtained through on-site sampling, factory testing, design drawings, material properties, etc. There are no ambiguous, unmeasurable, or dependent parameters. Those skilled in the art can fully implement this invention by following the contents described in this specification.

[0057] In one specific embodiment, the active control method for the camera body structure includes the following steps: Collect the three-phase current signal of the stator of the synchronous condenser, perform harmonic decomposition, and obtain the amplitude of each harmonic current. Substitute the values ​​into the formula for the effective radial vibration displacement of the stator core to calculate the effective radial vibration displacement of the stator core. Substitute the displacement results into the formula for the alternating bending stress amplitude of the stator core laminations to calculate the alternating bending stress amplitude of the core laminations. Substitute the stress results into the formula for the fatigue life loss rate per unit time of the stator core to calculate the fatigue life loss rate per unit time in real time. Based on the rated life loss rate target, the core target temperature is inverted using the formula for target control temperature, and the target flow rate of the cooling medium is calculated using the formula for target flow rate regulation of the cooling medium. The target flow rate is sent to the cooling system actuator to achieve closed-loop flow regulation, control the core temperature and fatigue wear rate, and complete the active health regulation of the synchronous condenser stator structure.

[0058] This solution requires no modification to the main structure of the synchronous condenser and can be implemented solely based on existing electrical quantity acquisition, temperature monitoring, and cooling regulation systems, demonstrating strong feasibility and engineering applicability.

[0059] This application also provides a system for performing the above-described active control method for the camera body structure, comprising: The effective vibration displacement amplitude acquisition module is used to collect the stator current signal of the synchronous condenser and calculate the effective radial vibration displacement amplitude of the stator core based on the electromagnetic vibration decoupling model. The alternating bending stress amplitude acquisition module is used to convert the effective radial vibration displacement amplitude of the stator core into the alternating bending stress amplitude of the stator core laminations based on the mechanical model of the equivalent simply supported beam of the laminated laminations. The fatigue life loss rate acquisition module is used to calculate the fatigue life loss rate of the stator core per unit time based on the alternating bending stress amplitude, according to the modified Miner fatigue cumulative damage theory. The active control module is used to obtain the target control temperature of the stator core based on the fatigue life loss rate of the stator core per unit time and the rated allowable fatigue life loss rate per unit time. It calculates the target control flow rate of the cooling medium through a heat transfer coupling model to actively control the temperature and fatigue life of the stator core.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A method for actively controlling the structure of a camera body, characterized in that, Includes the following steps: S1. Acquire the stator current signal of the synchronous condenser, and calculate the effective radial vibration displacement amplitude of the stator core based on the electromagnetic vibration decoupling model. S2. Based on the mechanical model of the equivalent simply supported beam of the stator core, the effective radial vibration displacement amplitude of the stator core is converted into the alternating bending stress amplitude of the stator core laminations. S3. Based on the modified Miner fatigue cumulative damage theory, the fatigue life loss rate of the stator core per unit time is calculated according to the alternating bending stress amplitude. S4. Based on the stator core fatigue life loss rate per unit time, and with the rated allowable life loss rate per unit time as the control target, the target control temperature of the stator core is obtained by inversion. The target flow rate of the cooling medium is calculated by using a heat transfer coupling model to actively regulate the temperature and fatigue life of the stator core.

2. The active control method for the body structure of the camera adjuster according to claim 1, characterized in that, In step S1, the formula for calculating the effective radial vibration displacement amplitude of the stator core is: in, This refers to the effective radial vibration displacement amplitude of the stator core. This is the vibration decoupling correction factor; This refers to the effective radial force-bearing area of ​​the stator core; For the first Secondary stator current harmonic magnetomotive force weighting coefficient; For the first Secondary stator current harmonic amplitude; The vacuum permeability; This refers to the equivalent radial stiffness of the stator core. It is the ratio of the excitation frequency to the natural frequency of the iron core; The damping ratio of the stator core structure.

3. The active control method for the body structure of the camera adjuster according to claim 2, characterized in that, The It is obtained by sampling from a current transformer and then undergoing harmonic decomposition. The The data was obtained through no-load vibration testing of the synchronous condenser and synchronous calibration with the current.

4. The active control method for the body structure of the camera adjuster according to claim 2, characterized in that, In step S2, the formula for calculating the amplitude of the alternating bending stress of the stator core laminations is as follows: in, The amplitude of alternating bending stress in the stator core laminations; This is the correction factor for lamination coupling; The elastic modulus of the core lamination material; The thickness of a single sheet of iron core lamination; This refers to the effective radial vibration displacement amplitude of the stator core. The span is the equivalent simply supported beam span of the laminated beam.

5. The active control method for the body structure of the camera adjuster according to claim 4, characterized in that, The modified Miner fatigue cumulative damage theory calculates the stator core fatigue life loss rate per unit time based on the alternating bending stress amplitude, specifically including: Based on the modified Miner fatigue cumulative damage theory, and taking into account the alternating bending stress amplitude and the real-time operating temperature of the core, the stress ratio correction coefficient and the temperature fatigue degradation coefficient are introduced to calculate the fatigue life loss rate of the stator core per unit time.

6. The active control method for the body structure of the camera adjuster according to claim 5, characterized in that, The formula for calculating the fatigue life loss rate of the stator core per unit time is: in, The fatigue life loss rate of the stator core per unit time; This is the stress ratio correction factor; This is the coefficient of temperature fatigue degradation; The frequency of the alternating stress cycle; This represents the amplitude of alternating bending stress in the iron core laminations. , For core material S N is the characteristic constant of the fatigue curve.

7. The active control method for the body structure of the camera adjuster according to claim 6, characterized in that, The formula for calculating the target control temperature of the stator core is as follows: in, Stator core target control temperature; Rated permissible lifespan loss rate per unit time; Reference temperature; Temperature influence coefficient; This is the stress ratio correction factor; The frequency of the alternating stress cycle; This represents the amplitude of alternating bending stress in the iron core laminations. , For core material S N is the characteristic constant of the fatigue curve.

8. The active control method for the body structure of the camera adjuster according to claim 7, characterized in that, The target flow rate of the cooling medium is calculated in segments, and the calculation formula is as follows: in, Cooling medium target flow rate regulation; , Maximum and minimum safe flow rates of the cooling system; : Inlet temperature of cooling medium; The maximum allowable operating temperature of the iron core; Heat generated by stator core losses; Heat transfer ratio coefficient; Effective heat exchange area; Stator core target control temperature.

9. The active control method for the body structure of a camera adjuster according to claim 1, characterized in that, The method of calculating the target flow rate of the cooling medium through a heat transfer coupling model to actively regulate the stator core temperature and fatigue life includes: The target flow rate of the cooling medium is calculated by a heat transfer coupling model, and the target flow rate is sent to the actuator of the cooling system to realize closed-loop regulation of the target flow rate of the cooling medium, control the temperature of the stator core and the fatigue wear rate, and complete the active regulation of the synchronous condenser body structure.

10. A system for performing the active control method of the camera body structure as described in any one of claims 1-9, characterized in that, include: The effective vibration displacement amplitude acquisition module is used to collect the stator current signal of the synchronous condenser and calculate the effective radial vibration displacement amplitude of the stator core based on the electromagnetic vibration decoupling model. The alternating bending stress amplitude acquisition module is used to convert the effective radial vibration displacement amplitude of the stator core into the alternating bending stress amplitude of the stator core laminations based on the mechanical model of the equivalent simply supported beam of the laminated laminations. The fatigue life loss rate acquisition module is used to calculate the fatigue life loss rate of the stator core per unit time based on the alternating bending stress amplitude, according to the modified Miner fatigue cumulative damage theory. The active control module is used to obtain the target control temperature of the stator core based on the fatigue life loss rate of the stator core per unit time and the rated allowable fatigue life loss rate per unit time. The target flow rate of the cooling medium is calculated by using a heat transfer coupling model to actively regulate the temperature and fatigue life of the stator core.

Images