88 results about "Electromechanical coupling" patented technology

Disclosed in the present invention is a physics-informed neural network-based thermo-mechanical coupling analysis method for an inertial microsystem, the method comprising: S1, configuring material parameters and boundary conditions of an inertial microsystem, and establishing a thermo-mechanical coupling analysis model; S2, performing electro-thermal coupling analysis to obtain a temperature distribution of the inertial microsystem; S3, performing thermo-mechanical coupling simulation analysis to obtain a thermal stress distribution of the microsystem; S4, predicting temperature fields of the microsystem by means of a physics-informed neural network; S5, using the temperature fields as boundary conditions for mechanical simulation of the microsystem, obtaining mechanical properties such as stress and strain of the microsystem; and S6, performing electromechanical coupling simulation analysis to analyze the impact of structural deformation on various parameters of electrical performance. The present invention improves the solution accuracy of the neural network by means of an improved adaptive weighting strategy, combines a complete polynomial basis function with the neural network, and introduces an expanded basis function to reduce the state dimensionality, thus reducing computational costs and time, achieving accurate prediction of temperature fields of microsystems at multiple moments, and allowing for computation of the performance of microsystems under electro-thermal-mechanical multi-physics coupling.

The invention relates to the field of motor and gear transmission systems, in particular to a method for optimizing design parameters of a transmission gear in an electric drive system.The method includes the steps that firstly, a two-dimensional finite element model of a permanent magnet synchronous motor is established, rotor stepped skewed slots and material magnetic saturation characteristics are accurately simulated, and an external characteristic MAP is generated; then calculating electromagnetic force density based on a Maxwell stress tensor method, mapping the electromagnetic force density to a multi-body dynamic model to construct a transverse coupling model, extracting an ECE reduced-order model based on a permanent magnet synchronous motor two-dimensional finite element model, forming a torsional vibration model in combination with a control algorithm, integrating a rigid-flexible coupling mechanical system, and establishing an electromechanical-rigid-flexible coupling model; and finally, through sensitivity analysis and a response surface model, with vibration acceleration and torsion amplitude as targets and gear strength as constraints, a Pareto optimal solution is solved by adopting a genetic algorithm, electromechanical coupling simulation precision is greatly improved, system vibration is effectively reduced, gear transmission reliability is enhanced, and the method is suitable for design of a high-dynamic-performance electric drive system.

The invention relates to a prospective control method of a multi-axis linkage machine tool in the field of intelligent manufacturing, which comprises the following steps: by analyzing the time difference distribution of each axis in a compensation time sequence, establishing a dynamic compensation matrix of multi-axis linkage, the matrix comprising the advanced starting time and speed regulation coefficient of each axis in different motion stages, determining personalized motion control parameters of each axis; according to the updated delay characteristic data and the curvature radius information of the track corner, the position deviation trend of each axis in the corner machining process is predicted, whether the motion time sequence of each axis needs to be adjusted or not is judged by comparing the deviation degree of the predicted position and the theoretical track, and an optimized multi-axis cooperative motion instruction is obtained; and the optimized multi-axis cooperative motion instruction is input into a servo controller of each axis, an actual position feedback signal of each axis is monitored at the same time, and the response consistency of each axis is ensured by calculating the real-time deviation value of an actual track and a theoretical track and dynamically correcting compensation parameters in an electromechanical coupling delay model.

The invention discloses a high-performance dielectric elastomer film, a driver capable of being driven at low voltage and a preparation method of the driver. According to the preparation method of the high-performance dielectric elastomer film, customization and balance of mechanical properties and electrical properties of a dielectric elastomer are realized by regulating and controlling the proportion of a chemical cross-linking agent, a high-polarity physical cross-linking agent and a monomer; according to the preparation method of the driver capable of being driven at the low voltage, a dielectric elastomer film and a flexible electrode are stacked through an optimized dry stacking method, the dielectric elastomer driver of a multilayer structure is constructed, and the driver has excellent performance under the low driving voltage. The preparation method has the potential of large-batch and large-scale production, and the prepared dielectric elastomer film has low Young modulus and enhanced strain hardening effect, can avoid electromechanical coupling instability, has high dielectric constant, has large-area strain in a low electric field, and can be used for preparing a dielectric elastomer film. The resulting dielectric elastomer driver can have a blocking force of 0.8 N and an energy density of 80 J / kg at a voltage of 500 V.

The application provides a detection system for interface peeling defects of a steel shell inner wall and concrete, which comprises a detection device, and the detection device comprises a signal generator, a signal amplifier, a plurality of piezoelectric material sheet assemblies, a signal acquisition assembly and a data analysis processor which are electrically connected in sequence; the plurality of piezoelectric material sheet assemblies are attached to the outer wall of the steel shell at intervals to form an electromechanical coupling system. The piezoelectric material sheet is arranged on the outer wall of the steel shell of the steel shell concrete component as a driver and a sensor at the same time, the electromechanical coupling impedance spectrum of the piezoelectric material is measured in a self-generating and self-receiving mode, the abnormal value of the electromechanical coupling impedance spectrum is analyzed, the RMSD of the electromechanical coupling impedance spectrum of the measuring point and the reference measuring point is calculated, the sensor position corresponding to the abnormal signal is screened out, and thus the accurate positioning and range estimation of the interface peeling defects are realized.

The invention discloses a fault detection method for an explosion-proof and intrinsic safety type hybrid electric appliance switch based on artificial intelligence, and relates to the technical field of intelligent operation and maintenance of power equipment, and the method comprises the following steps: S1, synchronously collecting multi-modal sensing data during the operation of the hybrid electric appliance switch through a plurality of intrinsic safety type sensors synchronously driven by a unified clock source; the multi-mode sensing data at least comprises electrical sensing data and mechanical vibration sensing data. According to the fault detection method for the flame-proof and intrinsic safety type hybrid electric appliance switch based on artificial intelligence, through a multi-mode synchronous acquisition and deep fusion architecture, the technical problem that fault feature acquisition is incomplete and asynchronous under strict explosion-proof constraints is effectively solved. Through a processing mechanism of edge calculation and cloud collaboration, accurate capture and intelligent screening of electromechanical coupling features are realized, the accuracy and reliability of fault diagnosis are improved by combining dual verification and a confidence fusion decision model, and effective technical support is provided for early fault early warning.

Mechanically and piezoelectrically anisotropic polymer fibers may be formed by spinning a polymer solution or gel that includes a high molecular weight crystallizable polymer and a liquid solvent. The solvent may be configured to interact with the polymer to facilitate chain alignment and, in some examples, create a higher crystalline content within the spun fibers. The polymer solution may also include a low molecular weight additive. The high and low molecular weight polymers may each be characterized by a bimodal molecular weight distribution where the molecular weight of the additive is less than the molecular weight of the crystallizable polymer. The polymer(s) and the additive(s) may be independently selected from vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, hexafluoropropene, vinyl fluoride, etc. The spun fibers may be oriented, annealed, poled, and woven or laminated to form a polymer thin film having a high elastic modulus and a high electromechanical coupling factor.

The application discloses a dynamic reliability evaluation method for a permanent magnet planetary gear transmission system, and belongs to the technical field of reliability analysis of electromechanical coupling transmission systems. The method is characterized in that: firstly, the service process of the system is divided into stages, and a random variable model is established; based on the wear evolution relationship, parameters of each stage are obtained through parameter mapping; then, stage high-fidelity unified electromechanical dynamics solving is performed, and frequency-related characteristic indexes are extracted; a multi-failure mode limit state vector is constructed, and a stage failure event is defined; on this basis, a multi-response Gaussian process proxy model is used for fitting and iterative updating of the limit state function through stage-by-stage active learning; the U function is used for initial screening of candidate samples, EFF is calculated and sorted, and a new sample point is selected according to the Top-K criterion to update the proxy model, until the convergence criterion is met; finally, the dynamic failure probability of the system is calculated by using the updated proxy model. The application realizes efficient and accurate evaluation of the failure probability of multiple failure modes, reduces the calculation cost, and improves the engineering applicability.

The invention belongs to the technical field of functional materials, and particularly relates to a 1-3 type lead metaniobate piezoelectric composite material and a preparation method and application thereof. The composite material takes lead metaniobate ceramic with a tungsten bronze structure as a one-dimensional piezoelectric phase and takes epoxy resin as a three-dimensional polymer phase. The ratio [lambda] / T of the transverse periodic dimension ([lambda]) of the ceramic column to the thickness (T) of the composite material is 0.1-0.6. The preparation method is characterized in that the ceramic column array is formed through precise cutting, cutting parameters are controlled to achieve the lambda / T ratio, and then resin encapsulation, curing, polishing and electrode preparation are conducted. According to the invention, the electromechanical coupling performance and stability of the composite material at ultrahigh temperature are synergistically improved by selecting the lead metaniobate ceramic with high Curie temperature and combining specific lambda / T structural parameters. The obtained material can still keep good performance at 350 DEG C, the maximum thickness electromechanical coupling coefficient kt can reach 0.35, and the material is suitable for high-temperature acoustic logging and underwater acoustic receiving transducers.

The invention provides a double-drive synchronous control method and system for a gantry machine tool, and the method comprises the steps: S1, building a flexible multi-body dynamic model of the gantry machine tool through combining the part flexibility and connection flexibility of the gantry machine tool; s2, constructing a dual-drive electromechanical coupling model of the gantry machine tool by combining servo system characteristics of the gantry machine tool and traditional system dynamic characteristics on the basis of the flexible multi-body dynamic model; and S3, according to the double-drive electromechanical coupling model, a self-adaptive control algorithm combining cross coupling double-drive synchronous control and sliding mode control is adopted to complete synchronous control of a double-drive system. According to the gantry machine tool double-drive synchronous self-adaptive control algorithm based on cross coupling double-drive synchronous control and sliding mode control, a cross feedback item is introduced, so that information of two drivers is correlated, the problem of double-drive synchronous error accumulation faced by a traditional double-drive parallel control or master-slave control method of a gantry machine tool is solved, and the system reliability is improved. The synchronous control of the gantry machine tool servo double-drive system is realized.

This invention discloses a nonlinear dynamic modeling method for crack evolution in a helical gear transmission system for vehicles, which includes the following steps: (1) establishing a calculation formula for meshing stiffness of the helical gear pair under cracked conditions using the slice integration method and the potential energy method; (2) establishing an equivalent circuit model of the motor by combining the principles of circuit theory and magnetic circuit theory with coordinate transformation relationship; (3) building an electromechanical coupling model of the motor-gear system based on the mechanical relationship between the motor and the gear transmission system; (4) establishing a model of the electromechanical coupling helical gear transmission system for vehicles and solving the influence mechanism of crack evolution of helical gears on the dynamic characteristics of the electromechanical coupling helical gear transmission system for vehicles; the beneficial effect is that this invention establishes a nonlinear fault dynamic model of the electromechanical coupling transmission system for new energy vehicles, which is of great significance for the design, optimization and life prediction of the helical gear transmission system for new energy vehicles.

Apparatus for near-field wireless energy transfer. A first layer provides or comprises a piezoelectric phase or a material with or adapted for electromechanical coupling; and a second layer provides or comprises a magnetostrictive phase or a material with or adapted for a magnetomechanical coupling. The second layer is mechanically and / or chemically coupled to the first layer to provide a composite structure.

The invention relates to the technical field of semiconductors, in particular to a surface acoustic wave resonance device, which comprises a substrate comprising a piezoelectric layer; the interdigital electrode is located on the piezoelectric layer, and the interdigital electrode sequentially comprises a first bus, a first gap part, an overlapping part, a second gap part and a second bus in the first direction; the piezoelectric layer sequentially comprises a first part, a first failure part, an effective part, a second failure part and a second part in the first direction, and the electromechanical coupling effect of the effective part is effective; the first bus is located on the first portion, the first gap portion is located on the first failure portion, the overlapping portion is located on the effective portion, the second gap portion is located on the second failure portion, and the second bus is located on the second portion. On the premise of not obviously influencing insertion loss, power tolerance and chip size, high-order nonlinearity, such as cubic nonlinearity, caused by electromechanical coupling outside a resonance area is effectively inhibited. In addition, the failure part extends to the bus, so that gap mode can be effectively inhibited.

The invention belongs to the technical field of piezoelectric ceramics, and particularly relates to a lead antimonate niobate-lead manganese niobate-lead zirconate titanate piezoelectric ceramic material and a method. Comprising a chemical general formula of xPb (Sb1 / 3Nb2 / 3) O3 <-0.04 > Pb (Mn1 / 3Nb2 / 3) O3 <-(0.96-x) Pb < 0.98 > Sr < 0.02 > (Zr < 0.5 > Ti < 0.5 >) O3 < + y wt% Fe < 2 > O < 3 >, wherein x is equal to 0.01 to 0.08, and y is equal to 0.01 to 2. The piezoelectric ceramic material is prepared from the following raw materials: Pb3O4, TiO2, ZrO2, Nb2O5, Sb2O3, MnO2 and SrCO3. The piezoelectric ceramic has a high piezoelectric coefficient and a high electromechanical coupling coefficient at the same time, compared with traditional P-8 series piezoelectric ceramics, the energy conversion rate can be improved, and the piezoelectric ceramic has low dielectric loss and high mechanical quality factor together with P-8 and has low loss in the energy conversion process.

The application discloses a mine electromechanical equipment operation safety situation evaluation method and system, relates to the technical field of mine electromechanical equipment safety monitoring and evaluation, and comprises the following steps: establishing an electromechanical coupling time-frequency observation layer, continuously acquiring dynamic characteristics of tension data, displacement data, current data and torque data, and generating a modal fingerprint baseline based on joint analysis; under the support of the modal fingerprint baseline, coherent decomposition is carried out, the modal drift speed is calculated, and a risk window in which the driving frequency gradually approaches is identified, so that the frequency evolution trend is revealed in advance. The application constructs an electromechanical coupling time-frequency observation system, extracts a modal fingerprint baseline, combines coherent decomposition and counterfactual playback to identify resonance risks in advance, realizes energy dissipation through staggered driving and structural damping, finally utilizes phase traction and phonon band gap structure to quickly dampen vibration, and forms a complete dynamic regulation and control closed-loop system.

The application discloses a photosensitive neuron driving electromechanical coupling system, a synchronous control method and application thereof, and electromechanical coupling bionic control technology field, and relates to the technical field of establishing a new type of neural circuit for interacting with external light energy; the neural circuit is used as a driving mechanical arm device of an electrical system to establish an electromechanical coupling circuit system; the response dynamics of the electromechanical coupling system is explored, and it is found that there are periodic bifurcations similar to "arc-shaped curves" and "folding shapes" in a multi-parameter space; capacitor is used as a carrier to study the Hamilton energy balance and complete synchronization of the electromechanical system under the electric field coupling; and resistance is used as a carrier to study the energy evolution of the mechanical arm coupling array when the functional parameters such as light intensity and coupling strength change.

The invention relates to a wheel polygon wear suppression method, an inter-harmonic excitation suppression circuit, a method and a medium, and relates to the technical field of railway traction transmission. On the basis of inter-harmonic excitation suppression and polygon wear feedback suppression, the malignant feedback effect caused by electromechanical coupling is weakened, and therefore suppression of polygon wear development of the wheel is achieved; the inter-harmonic excitation suppression comprises the following steps of: arranging an active power filter in a direct current link, and compensating direct current link power fluctuation caused by harmonic waves introduced by a rectifier; the polygon abrasion feedback suppression comprises the steps that compensation current is calculated based on the rotating speed fluctuation quantity under polygon abrasion excitation, and the T-axis current of the motor is compensated. According to the scheme, corresponding technical measures can be put forward from the two aspects of inter-harmonic excitation source suppression and polygon wear feedback suppression, comprehensive suppression of development of polygon wear of the wheel is achieved, polygon wear of the wheel caused by electrical parameters is reduced, and the method has the advantages of being low in implementation cost and not prone to being affected by the external environment.

The present disclosure belongs to the technical field of live-line work robots of power distribution networks, and provides a multi-parameter collaborative optimization method for an electromechanical coupling system based on a GRPO reinforcement learning algorithm, which comprises the following steps: acquiring multi-parameter operation data of the electromechanical coupling system during operation; pre-processing the acquired operation data; constructing a state vector based on the pre-processed operation data; constructing a GRPO reinforcement learning collaborative optimization model based on the GRPO reinforcement learning algorithm; inputting the state vector into the GRPO reinforcement learning collaborative optimization model; and the GRPO reinforcement learning collaborative optimization model obtains an optimization strategy through interactive learning with the electromechanical coupling system. The framework based on the reinforcement learning of the present disclosure enables the optimization strategy to adapt to changes in system operation conditions, environmental disturbances and parameter drift caused by component aging in real time, and maintains the robustness of the optimization effect.

The invention discloses a debugging method and system for high-precision mechanical and electrical equipment, and relates to the technical field of electrical equipment debugging, and the method comprises the steps: deploying a multi-source heterogeneous sensor on the high-precision mechanical and electrical equipment, collecting displacement, temperature, vibration and current signals, and generating multi-dimensional state data through time alignment and filtering processing; time sequence features of error disturbance are extracted based on the multi-dimensional state data, a dynamic composite error representation model is constructed, and a comprehensive positioning deviation estimated value is output; inputting the comprehensive positioning deviation estimated value into an electromechanical coupling virtual model in the high-fidelity digital twin platform, and automatically optimizing to generate an initial control parameter set; driving equipment to execute low-speed reciprocating motion by utilizing the initial control parameter set, acquiring a position response residual error in a reversing stage, identifying friction and hysteresis nonlinear characteristics on line based on the position response residual error, and constructing a feed-forward compensation function; and integrating the feed-forward compensation function and the initial control parameter set into an equipment bottom layer motion controller.

The application relates to the technical field of industrial equipment driving cooperative control methods, in particular to a multi-motor layered cooperative control method of a permanent magnet direct drive belt conveyor, a single-machine self-disturbance control + multi-machine layered cooperative control strategy is constructed, the core advantage of which lies in solving the cooperative control problem of the multi-motor system of the permanent magnet direct drive belt conveyor; meanwhile, aiming at the flexible connection characteristics of the long-distance conveying belt, the application introduces an electromechanical coupling model and time delay estimation, adopts a time delay feedforward + tension compensation compensation control strategy for the tail motor and the book total generation, compensates the tension wave and the transmission time delay, and effectively alleviates the speed lag and tension impact phenomenon in the operation process. In the aspect of anti-disturbance control, the single machine uses a sliding mode to enhance a nonlinear extended state observer SM-NLESO, considers the rapidity and overshoot suppression, can accurately estimate and compensate external disturbances such as parameter perturbation and sudden load, and significantly improves the robustness of the system.

A piezoelectric sensor, comprising at least one first electrode, at least one second electrode, and a piezoelectric material, wherein the piezoelectric material has an anisotropic electromechanical coupling and the at least one first and second electrodes are at least in part embedded in the piezoelectric material, the piezoelectric material having a first surface wherein the electrodes extend vertically within the piezoelectric material from the first surface.

The application relates to a permanent magnet synchronous motor multi-source nonlinear disturbance suppression method and system, and belongs to the technical field of permanent magnet synchronous motor control. The application comprises the following steps: establishing an electromechanical coupling discrete model of a permanent magnet synchronous motor actuator; designing a linear extended state observer based on a super-local model to observe system total disturbance in real time; decomposing the system total disturbance into multiple nonlinear disturbance factor components based on the electromechanical coupling discrete model, and calculating the contribution degrees of the components; designing a backstepping adaptive controller based on the contribution degrees, and combining the linear extended state observer to perform feedforward compensation; designing a deadbeat predictive current controller, and performing weighted fusion of the backstepping adaptive controller through a dynamic weight optimization strategy to generate a control voltage; and applying the finally generated d-axis and q-axis voltage control quantities to the permanent magnet synchronous motor actuator. The application can precisely suppress multi-source nonlinear disturbance, and improve the tracking accuracy, dynamic response speed and robustness of the system.

This invention discloses a performance optimization method for a tristable energy harvester under low-frequency excitation based on vibration resonance, belonging to the field of energy harvester optimization. The implementation method is as follows: a standard rectifier circuit is selected as the nonlinear collection circuit and connected to the energy harvester to achieve a stable DC output; a strongly nonlinear system model of the electromechanical coupled tristable energy harvester system is established; the slow variable equation of the tristable energy harvester system is derived using the variable separation method; the steady-state solution and analytical expression of the DC power of the tristable energy harvester system are derived using the harmonic balance method; an optimization model of the tristable energy harvester system under low-frequency excitation is obtained based on vibration resonance; the influence of low-frequency excitation amplitude, low-frequency excitation frequency, stiffness coefficient, time constant ratio, and electromechanical coupling coefficient on the collection performance of the tristable energy harvester system is analyzed using the optimization model, and the optimal combination is selected to achieve efficient energy harvesting of the tristable energy harvester system under low-frequency excitation.

This invention discloses a method for monitoring torsional resonance in a permanent magnet semi-direct drive sprocket transmission system of a scraper conveyor, belonging to the field of electromechanical coupling dynamics analysis and condition monitoring technology. A mathematical model of the permanent magnet synchronous motor, a torsional dynamics model of the planetary reducer, and an equivalent load model at the sprocket end are established. A unified electromechanical coupling state space model is constructed using electromagnetic torque, speed, and angular displacement as coupling variables, thereby determining the system's natural frequency. By analyzing the current signal, the mapping relationship between the current and the system's torsional vibration state is analyzed, achieving torsional resonance monitoring of the permanent magnet semi-direct drive sprocket transmission system of the scraper conveyor. This method fundamentally solves many problems, such as the difficulty in ensuring monitoring quality with external sensors under complex working conditions, achieving accurate monitoring and location of system torsional resonance with low maintenance costs. It provides an important theoretical method for realizing the dynamic characteristic analysis and reliable operation of the permanent magnet semi-direct drive sprocket transmission of scraper conveyors.

The invention discloses a heavy-duty gas turbine grid-connected test method and system, and the method comprises the steps: a power grid coupling load adjustment module is used for directly coupling a heavy-duty gas turbine with a power grid; the data acquisition module is used for acquiring multi-source sensor data and preprocessing the acquired original data to obtain first data; the power grid real disturbance input module is used for acquiring disturbance signals of the power grid; the multi-strategy cooperative control and protection module is used for controlling the gas turbine based on the first data and the disturbance signal and a target emergency strategy determined by adopting a three-layer distributed architecture; and the central integrated test management module is used for evaluating the control strategy in the target emergency strategy and generating a corresponding analysis report. The electromechanical coupling nature of gas turbine grid-connected operation is restored, real working condition reproduction is achieved, reliable data are provided for dynamic control logic optimization, closed-loop verification of the target emergency strategy under the power grid fault condition is achieved, and comprehensiveness and accuracy of the test result are ensured.

The invention provides a self-adaptive setting method and system for servo parameters of a five-axis machine tool under different poses. The method comprises the steps that S1, a machine tool component structure dynamic model is established according to a Nitsche principle-based partition variation method of flexible multi-body dynamics; s2, establishing a flexible multi-body dynamic model of the whole five-axis machine tool by using a floating reference coordinate system method; s3, establishing a five-axis machine tool electromechanical coupling model; and S4, based on the electromechanical coupling model of the five-axis machine tool, establishing a dynamic matching relationship between servo parameters and the pose of the machine tool through a self-adaptive sliding mode control algorithm driven by a nominal model, and completing self-adaptive setting of the servo parameters of the five-axis machine tool under different poses. According to the method, dynamic characteristics and servo system characteristics of the five-axis machine tool under different poses are comprehensively considered, the machine tool pose-related electromechanical coupling model is accurately constructed, and the dynamic performance of the machine tool is improved based on a self-adaptive setting method of servo parameters.

The invention provides an acoustic resonator, a filter and radio frequency equipment, and relates to the technical field of resonators. In the first direction, first grooves are formed in the two sides of the interdigital electrode, the depth of each first groove is L1, the sum of the thickness of the substrate, the thickness of the electrode layer and the thickness of the piezoelectric layer is L2, and L1 is larger than 0 and smaller than L2; the first direction is perpendicular to the length extension direction of the interdigital electrodes. The piezoelectric layer in the film layer below the interdigital electrode is at least subjected to corresponding patterning processing to form the first groove, the first groove serves as an isolation structure, electric field distribution is optimized, stray capacitance and inductance in the acoustic wave resonator are reduced, the mechanical load effect is reduced, acoustic wave leakage is limited, resonance is concentrated, and therefore the electromechanical coupling path is optimized, spurious propagation is restrained, and the acoustic wave resonator has the good mechanical performance. And performance breakthrough is realized.

The invention relates to an internal vibration device (10) for compacting a casting compound, comprising a vibration unit (12) with an electric motor (18), an electronic unit (14) which is electromechanically coupled to the vibration unit (12) via a hose connection (24) for controlling the electric motor (18), and a power supply unit (16) for supplying electrical power to the electronic unit (14) and the electric motor (18). It is proposed that the electric motor (18) can be controlled by the electronic unit (14) for such short periods that a critical operating condition, in particular a low energy state of the power supply unit (16), can be indicated by a change in its rotational speed (n).

The invention belongs to the technical field of urban rail vehicle operation and maintenance intelligentization, and discloses an intelligent operation and maintenance digital twin modeling method and system for an urban rail vehicle pantograph device. According to the method, a geometric physical model of the pantograph device is established based on physical characteristics and actual working conditions of the urban rail pantograph device; constructing a pantograph-catenary system electromechanical coupling dynamic model of the urban rail vehicle by referring to the related parameters; constructing a pantograph-catenary system behavior model of the urban rail vehicle, and associating multi-model data; according to a specific real-time operation and maintenance scene of a pantograph-contact network system of the urban rail vehicle, a twin database is built, data visualization processing is carried out, and an operation and maintenance result is displayed. According to the invention, the real-time interactivity in the operation and maintenance operation of the pantograph-contact network system is enhanced, and workers are helped to carry out real-time monitoring, intelligent diagnosis and predictive maintenance on the device more timely and effectively, so that the operation reliability of the pantograph and contact network equipment is obviously enhanced.

This invention relates to the fields of electronic component design and electromagnetic compatibility (EMC) technology, specifically disclosing a method and system for designing the dimensions of integrated piezoelectric ceramics based on electromagnetic interference frequencies. The method and system of this invention measure and analyze the impedance amplitude-frequency characteristics of the piezoelectric ceramic, identify its resonant frequency, and establish an electromechanical coupling model and a frequency offset model of the piezoelectric ceramic under weak coupling conditions. Since the constructed model is associated with material parameters, geometric dimensions, and resonant frequencies, the center frequency of the target interference signal is used as the design input, allowing for the reverse calculation and determination of the optimal geometric dimensions of the integrated piezoelectric ceramic for multiple interference signals. This design method and system of this invention realizes the transformation of piezoelectric ceramic filters from "selection and adaptation" to "precise design," enabling customized design of integrated piezoelectric ceramic components for specific electromagnetic interference, achieving efficient customized design and performance improvement of filters.