Reactor active damping method and system based on magnetostrictive effect positive compensation
By constructing a continuous relationship model between magnetostrictive effect and electromagnetic force deformation, the optimal compensation compressive stress was determined. By utilizing the positive compensation mechanism of magnetostrictive effect, the problem of reactor vibration was solved, and the overall vibration and cost of the reactor were significantly reduced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ELECTRIC POWER RES INST OF EAST INNER MONGOLIA ELECTRIC POWER
- Filing Date
- 2026-01-21
- Publication Date
- 2026-06-09
Smart Images
Figure CN121543374B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of vibration reduction technology for power equipment, and particularly relates to an active vibration reduction method and system for reactors based on positive compensation of magnetostriction effect. Background Technology
[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.
[0003] Reactors are crucial equipment in power systems, widely used for reactive power compensation, current limiting, and filtering. However, the vibration and noise generated during reactor operation are becoming increasingly prominent issues. This not only affects the operational stability and lifespan of the equipment itself but also has adverse impacts on the surrounding environment.
[0004] Reactor vibration mainly originates from two aspects: firstly, the magnetostrictive effect generated by the silicon steel sheets in the core under the action of an alternating magnetic field; and secondly, the periodic change of electromagnetic force at the air gap. Currently, passive vibration reduction measures are mostly adopted in engineering, such as adding damping materials, optimizing mechanical structures, and improving installation methods. However, these methods reduce vibration by simply suppressing magnetostriction, and generally suffer from limitations such as limited vibration reduction effect, high implementation cost, and complex subsequent maintenance, making it difficult to fundamentally solve the vibration problem. Summary of the Invention
[0005] To overcome the shortcomings of the prior art, the present invention provides an active vibration reduction method and system for reactors based on positive compensation of magnetostriction effect. This method can actively utilize and reshape the compensation mechanism of magnetostriction effect, so that the deformation generated by magnetostriction effect cancels out the deformation of electromagnetic force, thereby significantly reducing the overall vibration of the reactor from the source.
[0006] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:
[0007] The first aspect of this invention provides an active vibration reduction method for reactors based on positive compensation of magnetostriction effect.
[0008] Active vibration reduction methods for reactors based on positive compensation of magnetostriction effect include:
[0009] By analyzing the vibration source characteristics, the deformations excited on the reactor core by the magnetostrictive effect and electromagnetic force are quantified. By mapping material properties, a continuous relationship model between magnetostrictive strain, magnetic induction intensity, and compressive stress is constructed. Based on the deformations and relationship model, the optimal compressive stress is determined by calculating the compensation deformations provided by the magnetostrictive effect.
[0010] A preset core clamping structure is adopted, and the optimal compensation clamping stress is applied during the core manufacturing and assembly stages and maintained by pre-tightening elements. Vibration tests are performed on the reactor after the optimal compensation clamping stress is applied. If the preset target is not achieved, the stress adjustment direction and adjustment amount are determined based on phase analysis, and iterative fine-tuning is performed until the vibration suppression rate meets the preset target.
[0011] Furthermore, the vibration source characteristic analysis is performed through finite element simulation, which includes establishing an electromagnetic-structural-vibration coupled model of the reactor to simulate the magnetostrictive effect and deformation caused by electromagnetic force.
[0012] Furthermore, the material property mapping obtains discrete data points through magnetostrictive property testing, and constructs the continuous relationship model using a surface fitting method.
[0013] Furthermore, the magnitude of the optimal compensating clamping stress is configured such that the elongation deformation generated on the core is equal in amplitude and opposite in form to the core deformation caused by the electromagnetic force at the air gap of the reactor.
[0014] Furthermore, the iterative fine-tuning includes: measuring the reference vibration signal without applying the compensating clamping force and the vibration signal after applying the optimal compensating clamping stress under rated operating conditions; calculating the vibration suppression rate; and determining whether to start the fine-tuning program based on the vibration suppression rate.
[0015] Furthermore, the fine-tuning procedure includes: synchronously acquiring the excitation signal and vibration response signal of the reactor; extracting the phase difference between the excitation signal and the vibration response signal through spectrum analysis, and determining the fine-tuning direction based on the phase difference; adjusting the clamping stress according to the fine-tuning direction, and determining the final clamping stress through iterative optimization.
[0016] Furthermore, the determination of the fine-tuning direction includes: if the phase difference is basically consistent with the reference phase difference, it is determined that the compensation is insufficient and the clamping stress needs to be increased; if the phase difference is 180 degrees different from the reference phase difference, it is determined that the compensation is excessive and the clamping stress needs to be reduced.
[0017] The second aspect of the present invention provides an active vibration reduction system for reactors based on positive compensation of magnetostriction effect.
[0018] An active vibration reduction system for reactors based on positive compensation of the magnetostrictive effect includes:
[0019] The sensor unit is used to monitor the applied clamping stress and the vibration response of the reactor;
[0020] The control unit is configured to: quantify the deformations excited on the reactor core by the magnetostrictive effect and electromagnetic force respectively through vibration source characteristic analysis; construct a continuous relationship model between magnetostrictive strain, magnetic induction intensity, and compressive stress through material property mapping; determine the optimal compensation compressive stress by calculating the compensation deformation provided by the magnetostrictive effect based on the deformations and relationship model; and, if the vibration test does not meet the preset target, determine the stress adjustment direction and adjustment amount based on phase analysis, and iteratively fine-tune until the vibration suppression rate meets the preset target.
[0021] The core clamping structure is configured to: employ a preset core clamping structure to apply the optimal compensated clamping stress during the core manufacturing and assembly stages, and maintain it through a pre-tightening element;
[0022] The vibration testing unit is configured to perform vibration testing on the reactor after the optimal compensation clamping stress is applied.
[0023] Furthermore, the core clamping structure includes a tensioning screw, a nut, and a preload element; wherein the preload element is a disc spring used to maintain the applied optimal compensating clamping stress.
[0024] Furthermore, the sensor unit includes a thin-film pressure sensor and a laser vibrometer, which are used to measure clamping stress and vibration displacement, respectively.
[0025] The above one or more technical solutions have the following beneficial effects:
[0026] This invention determines the optimal compensating clamping stress through vibration source characteristic analysis and material property mapping; it employs a pre-set core clamping structure to apply the optimal compensating clamping stress during the core manufacturing and assembly stages, and maintains it through pre-tightening elements; then, it conducts vibration tests on the reactor after applying the optimal compensating clamping stress. Compared to existing technologies, this invention does not simply suppress magnetostriction, but actively utilizes and reshapes it, causing the resulting deformation to cancel out the electromagnetic force deformation, thereby significantly reducing the overall vibration of the reactor from the source.
[0027] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.
[0029] Figure 1 This is a flowchart of the reactor active vibration reduction method based on positive compensation of magnetostriction effect in Embodiment 1 of the present invention.
[0030] Figure 2 This is a diagram showing the effect of vibration superposition in the current technology without compensation.
[0031] Figure 3 This is a schematic diagram of the relationship between the magnetostrictive properties of oriented silicon steel sheets at 1.5 T and compressive stress in Embodiment 1 of the present invention.
[0032] Figure 4 This is a diagram showing the effect of reactor vibration cancellation when 3.3 MPa is applied in Embodiment 1 of the present invention.
[0033] Figure 5 This is a structural diagram of the core clamping structure in Embodiment 2 of the present invention. Detailed Implementation
[0034] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0035] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.
[0036] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.
[0037] Example 1
[0038] This embodiment discloses an active vibration reduction method for reactors based on positive compensation of magnetostriction effect.
[0039] like Figure 1 As shown, the active vibration reduction method for reactors based on positive compensation of magnetostriction effect includes:
[0040] Step S1: Quantify the deformations excited on the reactor core by magnetostrictive effect and electromagnetic force respectively through vibration source characteristic analysis; construct a continuous relationship model between magnetostrictive strain, magnetic induction intensity and compressive stress through material property mapping; determine the optimal compensation compressive stress by calculating the compensation deformation provided by magnetostrictive effect based on the deformation and relationship model.
[0041] Step S2: Using a preset core clamping structure, apply the optimal compensation clamping stress during the core manufacturing and assembly stages, and maintain it through pre-tightening elements; perform vibration testing on the reactor after applying the optimal compensation clamping stress. If the preset target is not achieved, determine the stress adjustment direction and adjustment amount based on phase analysis, and iteratively fine-tune until the vibration suppression rate meets the preset target.
[0042] Based on the above process, this invention can actively utilize and reshape the compensation mechanism of the magnetostrictive effect, causing the deformation generated to cancel out the electromagnetic force deformation, thereby significantly reducing the overall vibration of the reactor from the source. To facilitate understanding of the technical solution of this invention, the specific implementation methods of this invention will be further explained and described below.
[0043] In step S1, the deformations excited on the reactor core by the magnetostrictive effect and electromagnetic force are quantified through vibration source characteristic analysis; a continuous relationship model between magnetostrictive strain, magnetic induction intensity and compressive stress is constructed through material property mapping; based on the deformations and relationship model, the optimal compensation compressive stress is determined by calculating the compensation deformations provided by the magnetostrictive effect.
[0044] The core of determining the optimal compensating clamping stress lies in determining an optimal clamping stress value. The principle for determining this stress value is not to make the magnetostrictive strain zero, but to ensure that it produces a specific, controllable positive magnetostrictive strain under the operating magnetic flux density of the reactor. The purpose of this specific positive strain is to ensure that the elongation deformation generated on the core is equal in amplitude and opposite in form to the core deformation (usually a contraction tendency) caused by the electromagnetic force at the reactor air gap. This achieves active cancellation of the two main sources of deformation; that is, the magnitude of the optimal compensating clamping stress is configured so that the elongation deformation generated on the core is equal in amplitude and opposite in form to the core deformation caused by the electromagnetic force at the reactor air gap. This can be achieved through the following methods:
[0045] Step S1-1: Vibration source characteristic analysis.
[0046] The vibration source characteristics were analyzed using finite element simulation to quantify the peak displacements induced on the iron core by the magnetostrictive effect and the air gap electromagnetic force, respectively, under uncompensated conditions. and (Assuming elongation deformation is positive and contraction deformation is negative). Finite element simulation includes: establishing an electromagnetic-structural-vibration coupled model of the reactor to simulate the deformation caused by magnetostriction and air gap electromagnetic force.
[0047] First, a simulation model is constructed and the physical fields are set. In finite element analysis software, a two-dimensional or three-dimensional geometric model of the reactor, including key components such as the core, coils, and air gap, is established. In the constructed model, the core material is subjected to nonlinearity. B - H The magnetization curve is designed to accurately simulate the magnetic saturation effect of silicon steel sheets, while the coil is configured with its actual conductivity and number of turns.
[0048] Next, transient electromagnetic field analysis is performed to obtain the excitation source. A sinusoidal AC excitation consistent with the actual operating conditions is applied to the coil, and the spatially distributed and time-varying magnetic flux density over a complete working cycle is calculated by solving Maxwell's equations. Based on this magnetic field result, the electromagnetic force acting on various parts of the iron core, which serves as the main excitation source of vibration, was calculated using Maxwell's stress tensor method. .
[0049] Then, loads are applied separately in the structural field to decouple the vibration source contribution. The calculated electromagnetic force is then... As nodal loads, they are mapped onto the corresponding mesh of the structural mechanics module. Simultaneously, functions previously obtained experimentally to characterize the relationship between magnetostrictive strain, magnetic flux density, and stress are applied. The magnetostrictive strain characteristic surface model is integrated into the structural simulation. In this benchmark analysis, the core clamping stress is set. This allows the model to be based on the real-time magnetic flux density of each unit. The original magnetostrictive strain under stress-free conditions was dynamically calculated and applied to the iron core as another key excitation source.
[0050] Finally, two independent transient structural dynamics solutions were performed to quantify the vibration sources. Under boundary conditions simulating the actual installation of the reactor (e.g., a fixed core bottom surface), the first solution applied only electromagnetic forces. As an excitation, the vibration response of the iron core is obtained by solving, and its peak displacement is recorded. This peak displacement is the peak displacement caused solely by the air gap electromagnetic force. In the second solution, only the magnetostrictive strain under stress-free conditions was applied as excitation. The vibration response of the iron core was obtained, and its peak displacement was recorded. This peak displacement is the peak displacement caused solely by the magnetostrictive effect. .
[0051] Step S1-2: Material property mapping.
[0052] Material property mapping is achieved by obtaining discrete data points through magnetostrictive property testing, and then constructing the continuous relationship model using a surface fitting method. Specifically, the magnetostrictive properties of silicon steel sheets are measured under a series of discrete compressive stresses. and magnetic induction intensity Magnetostrictive strain values under combination Because the experiment could not cover all continuous magnetic induction intensities. and compressive stress Based on these limited discrete data points, the following approach is adopted: B Numerical methods such as spline surface fitting are used to construct a continuous, smooth, and high-precision continuous relationship model, namely, a magnetostrictive strain characteristic surface model. This model can be used to predict accurate magnetostrictive strain values under arbitrary working magnetic flux density and compressive stress.
[0053] use B Numerical methods such as spline surface fitting are used to construct a continuous, smooth, and high-precision continuous relationship model. Specifically, a set of discrete data points is obtained through magnetostrictive property testing of actual silicon steel sheets. . Magnetic induction intensity and compressive stress As two independent variables, the magnetostrictive strain value As the dependent variable, numerical computation software (such as MATLAB, Python SciPy, etc.) is used. B A spline surface fitting tool is used to fit the discrete data points. This process automatically determines a smooth surface defined by a control point grid by solving a linear least squares problem. This surface best approximates all experimental data points. The resulting magnetostrictive strain characteristic surface model... As a calculator, it can be used to input any value within the defined domain. The value is calculated, and a high-precision predicted value is output. ;in, , and Corresponding to , and This is a discrete set. This overcomes the limitation of discrete data tables, which can only query a finite number of points.
[0054] Step S1-3: Stress solution.
[0055] Based on the finite element simulation results, To achieve the ultimate goal, the required compensation deformation needs to be provided by the magnetostrictive effect. This allows for the determination of the required magnetostrictive strain. Finally, by analyzing the material property curves, the optimal operating magnetic flux density was determined. Magnetostrictive strain can be generated. The corresponding compressive stress value, i.e., the optimal clamping stress value. .
[0056] Step S1-4: Multiphysics coupling simulation verification.
[0057] An electromagnetic-structural-vibration coupled model of the reactor was established to simulate the effect of applying the optimal clamping stress value. The overall vibration response of the core after stress was measured to verify the countermeasures effect. Specifically:
[0058] Repeat step S1-1 to construct a simulation model and set up the physical field during the simulation of deformation caused by magnetostriction and electromagnetic force, and perform transient electromagnetic field analysis to obtain the excitation source. Then, map the electromagnetic results to the structural field, and apply the calculated electromagnetic force... As nodal loads, they are mapped onto the corresponding mesh of the structural mechanics module. Simultaneously, functions characterizing the relationship between magnetostrictive strain, magnetic flux density, and stress, obtained beforehand through experiments, are used. It is integrated into the structural simulation as a surface model of magnetostrictive strain characteristics. This model is based on the real-time magnetic flux density of each element. and the pre-applied optimal clamping stress The magnetostrictive strain was dynamically calculated. And apply it as another key source of motivation to the iron core.
[0059] Finally, transient structural dynamics solutions were performed to verify the results. Under the boundary conditions simulating the actual installation of the reactor (e.g., fixing the bottom surface of the core), the structural field simultaneously receives electromagnetic forces. and subjected to optimal compressive stress Modulated magnetostrictive strain By solving the structural dynamics equations using these two physical excitations, we obtain the displacements of the core under three simultaneous excitation sources.
[0060] In step S2, a preset core clamping structure is used to apply the optimal compensation clamping stress during the core manufacturing and assembly stages, and it is maintained by a pre-tightening element. A vibration test is performed on the reactor after applying the optimal compensation clamping stress. If the preset target is not met, the stress adjustment direction and amount are determined based on phase analysis, and iterative fine-tuning is performed until the vibration suppression rate meets the preset target. Specifically, this can be achieved through the following methods:
[0061] 1) Core clamping structure design and pre-pressurization.
[0062] Design a mechanical structure capable of applying a uniform, stable, and precisely controllable clamping force to the reactor core. During the core manufacturing and assembly stages, the optimal clamping stress determined in step S1 is applied through this core clamping structure, and this optimal clamping stress is reliably maintained long-term using a preload element (such as a high-performance disc spring). During pre-pressurization, the nut of the tensioning screw is tightened, and the diaphragm pressure sensor reading is... This allows for the application of uniform and stable compressive stress to the iron core.
[0063] 2) Reactor vibration test.
[0064] Vibration tests were conducted on the reactor after applying optimal compensation clamping stress to verify its vibration reduction effect. When simulating the application of optimal compensation clamping stress, it is not necessary to apply pressure to the core in the finite element simulation; instead, the magnetostrictive strain is applied as the magnetostrictive strain under a specific pressure. That's it. Based on the measured data, the applied optimal clamping stress can be fine-tuned to achieve the best vibration cancellation effect.
[0065] Verification of vibration reduction effect during reactor vibration testing includes: measuring the reference vibration signal without compensation clamping force and the vibration signal after applying optimal compensation clamping stress under rated operating conditions; calculating the vibration suppression rate and determining whether to initiate the fine-tuning program based on the vibration suppression rate. The fine-tuning program involves simultaneously acquiring the reactor's excitation signal and vibration response signal; extracting the phase difference between the excitation signal and vibration response signal through spectrum analysis and determining the fine-tuning direction based on the phase difference; adjusting the clamping stress according to the fine-tuning direction; and determining the final clamping stress through iterative optimization. If the phase difference is basically consistent with the reference phase difference, it is determined that the compensation is insufficient and the clamping stress needs to be increased; if the phase difference is close to 180 degrees from the reference phase difference, it is determined that the compensation is excessive and the clamping stress needs to be reduced.
[0066] In the specific implementation process, firstly, under the rated operating conditions of the reactor, a laser vibration meter is used to measure the time-domain signal of the vibration displacement without the application of active compensation clamping force by measuring the vertical iron yoke. And record the peak-to-peak value of its vibration displacement. Under identical test conditions, the optimal clamping stress was measured. Subsequently, the vibration displacement time-domain signal at the same measuring point and its peak value Calculate the vibration suppression rate. If the vibration suppression rate If the vibration reduction rate reaches or exceeds the preset target (e.g., ≥90%), the vibration reduction effect is considered to meet the requirements and no adjustment is needed; if the vibration suppression rate is... If the requirements are not met, the fine-tuning process will be initiated.
[0067] The implementation of iterative fine-tuning includes:
[0068] The first step, data acquisition and phase analysis, involves simultaneously acquiring reference signals and vibration response signals using a data acquisition system. The reference signal... The excitation current or voltage signal from the reactor is taken; this signal is in phase with Maxwell's electromagnetic force; vibration response signal The measured vibration displacement signal after compensation. The vibration response signal. and reference signal Perform spectral analysis to extract the phase difference at the main excitation frequency (e.g., 100 Hz). .
[0069] The second step is to determine the direction of fine-tuning.
[0070] When the phase difference of the main frequency components is measured Phase difference measured in benchmark test Basically the same (i.e.) This indicates that the main component of the residual vibration is still electromagnetic force deformation. Dominant. Positive deformation caused by magnetostriction. If the pressure is too low, it will not be sufficient to offset the deformation caused by the electromagnetic force, and therefore the overall vibration pattern will remain the same as before compensation. In this case, the clamping stress should be increased.
[0071] When the phase difference of the main frequency components is measured Phase difference measured in benchmark test The difference is about 180 degrees (i.e.) This indicates that magnetostriction produces positive deformation. It has exceeded the deformation caused by electromagnetic force. This causes the overall deformation of the iron core to be dominated by the magnetostrictive effect. Since the deformation trends of the two are opposite, the vibration phase is reversed. At this time, the clamping stress should be reduced.
[0072] The third step is to determine the fine-tuning amount.
[0073] Initial fine-tuning: Based on the determination of the fine-tuning direction, the clamping stress is adjusted by a preset step size. ( (5%). That is, if the compensation is insufficient, it will be adjusted to... If the compensation is excessive, adjust accordingly. Then iteration and convergence, i.e., applying adjusted stress. Then, the peak-to-peak value of the vibration displacement was measured again. And compare and :
[0074] like This indicates that the adjustment direction is correct. You can then continue adjusting in the same direction with the same or decreasing step sizes until the vibration displacement is reached. It no longer decreases significantly or begins to increase. If This indicates that the adjustment step size may be too large; the step size should be reduced and the adjustment reversed. Through several iterations, the peak-to-peak value of the vibration displacement was found. The minimum clamping stress value is the optimal value determined by the final fine-tuning. .
[0075] To further demonstrate the significant advancements of this invention, the following experimental comparisons were conducted in this embodiment:
[0076] like Figure 2 The diagram shown illustrates the superposition effect of vibration in the uncompensated state in the prior art. Specifically, the core vibration is the result of the combined action of magnetostrictive force and Maxwell's electromagnetic force. Figure 2 The values of the three curves are all from simulation calculations; the blue line represents the vibration displacement of the iron core under the action of Maxwell's electromagnetic force only, the red line represents the vibration displacement of the iron core under the action of magnetostrictive force only, and the black line represents the vibration displacement of the iron core under the combined action of the two forces.
[0077] like Figure 3 The diagram shows the relationship between the magnetostrictive properties of the grain-oriented silicon steel sheet and compressive stress at 1.5 T. When the silicon steel sheet is not under compressive stress, the peak-to-peak value of the magnetostriction curve is negative, meaning that the core will shorten under magnetostrictive force. Gradually increasing the compressive stress on the silicon steel sheet will cause the peak-to-peak value of the magnetostriction curve to turn from negative to positive, meaning that the core will elongate under magnetostrictive force. Reasonably controlling the compressive stress value will allow the effects of the two forces to cancel each other out as much as possible.
[0078] like Figure 4 The diagram shows the effect of the present invention in canceling reactor vibration when a force of 3.3 MPa is applied. When a compressive force of 3.3 MPa is applied to the silicon steel sheet, the peak-to-peak value of the magnetostriction curve is positive; therefore, the vibration displacement of the core is positive only under magnetostrictive force. The displacement caused by the resultant force under 3.3 MPa compressive stress is almost zero, i.e., it cancels out the vibration.
[0079] It is not hard to see that Figure 2 As shown in the diagram, under the conventional state without applied compressive stress, the combined action of the two forces causes significant vibration and displacement of the iron core; however, through... Figure 3 , Figure 4 As shown, under the precise application of 3.3 MPa compressive stress, the peak-to-peak value of the magnetostrictive curve changes from negative to positive, causing the displacement direction caused by the magnetostrictive force to reverse. Ultimately, this almost completely cancels out the displacement caused by the Maxwell electromagnetic force, resulting in a near-zero net force vibration displacement. This demonstrates that active control of compressive stress can effectively suppress core vibration, significantly reducing the vibration of the reactor or transformer. In other words, the method proposed in this invention for adjusting the magnetostrictive properties of silicon steel sheets by applying controllable compressive stress can effectively achieve mutual cancellation of the magnetostrictive force and the Maxwell electromagnetic force in vibration.
[0080] Example 2
[0081] This embodiment discloses an active vibration reduction system for reactors based on positive compensation of magnetostriction effect.
[0082] An active vibration reduction system for reactors based on positive compensation of the magnetostrictive effect includes:
[0083] The sensor unit is used to monitor the applied clamping stress and the vibration response of the reactor;
[0084] The control unit is configured to: quantify the deformations excited on the reactor core by the magnetostrictive effect and electromagnetic force respectively through vibration source characteristic analysis; construct a continuous relationship model between magnetostrictive strain, magnetic induction intensity, and compressive stress through material property mapping; determine the optimal compensation compressive stress by calculating the compensation deformation provided by the magnetostrictive effect based on the deformations and relationship model; and, if the vibration test does not meet the preset target, determine the stress adjustment direction and adjustment amount based on phase analysis, and iteratively fine-tune until the vibration suppression rate meets the preset target.
[0085] The core clamping structure is configured to: employ a preset core clamping structure to apply the optimal compensated clamping stress during the core manufacturing and assembly stages, and maintain it through a pre-tightening element;
[0086] The vibration testing unit is configured to perform vibration testing on the reactor after the optimal compensation clamping stress is applied.
[0087] like Figure 5 As shown, the core clamping structure includes a tensioning screw, a nut, and a preload element; wherein the preload element is a disc spring used to maintain the applied optimal compensating clamping stress; the sensor unit includes a thin-film pressure sensor and a laser vibrometer, used to measure the clamping stress and vibration displacement, respectively. Specifically, the nut and tensioning screw are clamped together by a threaded connection, and the thin-film pressure sensor is placed under the nut.
[0088] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.
[0089] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.
Claims
1. A method for active vibration reduction of reactors based on positive compensation of magnetostriction effect, characterized in that, include: By analyzing the characteristics of the vibration source, the deformation of the reactor core excited by the magnetostrictive effect and electromagnetic force is quantified. Specifically, firstly, a simulation model is constructed and the physical field is set. In the simulation model, the core material is given a nonlinear BH magnetization curve to accurately simulate the magnetic saturation effect of silicon steel sheets. Then, transient electromagnetic field analysis is performed to obtain the excitation source, that is, sinusoidal AC excitation consistent with the actual working condition is applied to the coil. By solving Maxwell's equations, the spatially distributed magnetic flux density that varies with time over a complete working cycle is calculated. Based on the magnetic field result, the electromagnetic force acting on each part of the iron core as the main excitation source of vibration is calculated using Maxwell's stress tensor method. Next, loads are applied to the structural field to decouple the vibration source contributions. Finally, two independent transient structural dynamics solutions are performed to quantify each vibration source. In the first solution, only electromagnetic force is applied as excitation to obtain the vibration response of the core, and the corresponding displacement peak is recorded as the displacement peak caused solely by the air gap electromagnetic force. In the second solution, only magnetostrictive strain under stress-free conditions is applied as excitation to obtain the vibration response of the core, and the corresponding displacement peak is recorded as the displacement peak caused solely by the magnetostrictive effect. By mapping material properties, a continuous relationship model between magnetostrictive strain, magnetic induction intensity, and compressive stress is constructed. Based on the deformation and relationship model, the optimal compensating compressive stress is determined by calculating the compensation deformation provided by the magnetostrictive effect. The magnitude of the optimal compensating compressive stress is configured such that the elongation deformation generated on the core is equal in amplitude and opposite in form to the core deformation caused by the electromagnetic force at the air gap of the reactor. A preset core clamping structure is adopted, and the optimal compensation clamping stress is applied during the core manufacturing and assembly stages and maintained by pre-tightening elements. Vibration testing is performed on the reactor after applying the optimal compensation clamping stress. If the preset target is not met, the stress adjustment direction and amount are determined based on phase analysis, and iterative fine-tuning is performed until the vibration suppression rate meets the preset target. The iterative fine-tuning includes: measuring the reference vibration signal without compensation clamping force and the vibration signal after applying the optimal compensation clamping stress under rated operating conditions; calculating the vibration suppression rate; and determining whether to initiate the fine-tuning program based on the vibration suppression rate. The fine-tuning procedure includes: synchronously acquiring the excitation signal and vibration response signal of the reactor; extracting the phase difference between the excitation signal and vibration response signal through spectrum analysis, and determining the fine-tuning direction based on the phase difference; adjusting the clamping stress according to the fine-tuning direction, and determining the final clamping stress through iterative optimization; The determination of the fine-tuning direction includes: if the phase difference is basically consistent with the reference phase difference, it is determined that the compensation is insufficient and the clamping stress is increased; if the phase difference is 180 degrees different from the reference phase difference, it is determined that the compensation is excessive and the clamping stress is reduced.
2. The active vibration reduction method for reactors based on positive compensation of magnetostriction effect as described in claim 1, characterized in that, The vibration source characteristic analysis is performed through finite element simulation, which includes establishing an electromagnetic-structural-vibration coupled model of the reactor to simulate the magnetostrictive effect and deformation caused by electromagnetic force.
3. The active vibration reduction method for reactors based on positive compensation of magnetostriction effect as described in claim 1, characterized in that, The material property mapping is achieved by obtaining discrete data points through magnetostrictive property testing, and a continuous relationship model is constructed using a surface fitting method.
4. An active vibration reduction system for reactors based on positive compensation of magnetostriction effect, employing the active vibration reduction method as described in any one of claims 1-3, characterized in that, include: The sensor unit is used to monitor the applied clamping stress and the vibration response of the reactor; The control unit is configured to: quantify the deformations excited on the reactor core by the magnetostrictive effect and electromagnetic force respectively through vibration source characteristic analysis; construct a continuous relationship model between magnetostrictive strain, magnetic induction intensity, and compressive stress through material property mapping; and determine the optimal compensation compressive stress by calculating the compensation deformation provided by the magnetostrictive effect based on the deformations and relationship model. Furthermore, if the vibration test fails to meet the preset target, the stress adjustment direction and amount are determined based on phase analysis, and iterative fine-tuning is performed until the vibration suppression rate meets the preset target. The core clamping structure is configured to: employ a preset core clamping structure to apply the optimal compensated clamping stress during the core manufacturing and assembly stages, and maintain it through a pre-tightening element; The vibration testing unit is configured to perform vibration testing on the reactor after the optimal compensation clamping stress is applied.
5. The reactor active vibration reduction system based on positive compensation of magnetostriction effect as described in claim 4, characterized in that, The core clamping structure includes a tensioning screw, a nut, and a preload element; wherein the preload element is a disc spring, used to maintain the applied optimal compensating clamping stress.
6. The reactor active vibration reduction system based on positive compensation of magnetostriction effect as described in claim 4, characterized in that, The sensor unit includes a thin-film pressure sensor and a laser vibrometer, which are used to measure compression stress and vibration displacement, respectively.