245 results about "Resonance point" patented technology

The invention belongs to the technical field of connectors and discloses a design method for a low-loss cable connector without resonance points, comprising: designing a spiral gradient groove structure on the surface of an inner conductor based on the impedance continuity principle, establishing a composite gradient impedance theoretical model of the connector, constructing a dielectric constant gradient distribution model of a double insulating layer, and setting a transition function between an inner layer and an outer layer; solving the S parameters and electric field distribution of the connector through electromagnetic-thermal coupling finite element simulation, optimizing the spiral angle θ and the gradient index n, establishing a quantitative model of the surface roughness of the conductor and high-frequency loss, and determining a threshold range of the surface roughness through calculation of the quantitative model; performing global optimization of structural parameters based on a multi-objective genetic algorithm, outputting a theoretical design parameter set and a report collection of performance verification, eliminating the resonance point problem of traditional connectors, and providing excellent low-loss performance in the full frequency band, which is particularly suitable for high-frequency and high-power transmission environments.

The invention discloses a stator blade shape-following frequency modulation design method based on a bending vibration mode and application, belongs to the field of vibration design of stator blades of aero-engines and gas turbines, and is suitable for vibration frequency modulation design of non-cantilever type stator structure blades (such as fans and gas compressor stators) with inner rings and outer rings in the aero-engines or the gas turbines. According to the method, firstly, static frequency and dynamic frequency modal analysis is carried out through finite element modeling, and dangerous resonance points and corresponding vibration modes in a working rotating speed range are recognized by combining a Campbell diagram; based on a vibration mode amplitude normalization result, setting a vibration degree parameter and a scale factor, selecting a high response node and carrying out directed disturbance, and updating a structure model to improve a target vibration mode frequency; and through frequency amplification verification and iterative optimization, geometric reconstruction and frequency modulation confirmation are finally completed in combination with aerodynamic performance and processing requirements. The method can realize rapid and accurate frequency modulation of a specific bending vibration mode, avoids introduction of new resonance, and has the advantages of high efficiency, strong adaptability and the like.

The invention discloses an ultra-low profile broadband circularly polarized microstrip patch antenna array and a design method thereof, the antenna array is constructed on a single-layer thin dielectric substrate, and an antenna unit is formed by combining a substrate integrated waveguide resonant cavity and a microstrip patch resonator embedded in the center of the substrate integrated waveguide resonant cavity. On the premise that the antenna size is not increased, the combination of the double resonators is realized. The adjacent antenna units are arranged at zero intervals and share the metal columns surrounding the edge of the substrate integrated waveguide resonant cavity. Two pairs of polarization orthogonal degenerate modes with similar resonance characteristics are introduced by utilizing a central gap, an annular gap and four symmetrical gaps connected with the central gap and the annular gap, so that four resonance points with similar radiation characteristics and similar resonance frequencies and two axial ratio zero points are formed, and synchronous broadening of impedance bandwidth and axial ratio bandwidth is realized. In addition, a radiation zero point is generated at the position close to the upper edge of the passband along the radiation counteracting effect on the two sides of the annular gap, and therefore the out-of-band rejection performance of the antenna is improved.

The invention discloses a rotor system with a resonance point self-test function, a measurement method, equipment and a medium. The system comprises a controller, an active electromagnetic bearing, a radial vibration displacement sensor and a spectrum analyzer, the controller is used for generating a control signal according to the user configuration parameters and sending the control signal to the active electromagnetic bearing; the active electromagnetic bearing is used for outputting electromagnetic excitation force to the rotor system according to the control signal, so that the rotor system generates radial vibration displacement under the action of the electromagnetic excitation force; the radial vibration displacement sensor is used for collecting a radial vibration displacement signal of the rotor system and sending the radial vibration displacement signal to the spectrum analyzer; and the spectrum analyzer is used for generating a spectrum signal according to the radial vibration displacement signal and determining a rotor resonance point according to the spectrum signal. According to the technical scheme, self-testing of the resonance point of the rotor system can be realized without a speed increasing and decreasing test and an additional excitation device, the safety of the rotor is guaranteed, and uncontrollable accidents are avoided.

The invention belongs to the technical field of testing equipment, and particularly relates to a multipurpose high-frequency fatigue testing machine which comprises main control equipment and a fatigue testing machine body, the fatigue testing machine body comprises a bottom machine and an electromagnetic high-frequency generating machine body, and a balance weight table is assembled under the electromagnetic high-frequency generating machine body through connecting rod connection; clamp assemblies are assembled on the surface of the bottom machine and the lower surface of the counterweight table; the multiple balance weights are adjustably stacked on the surface of the balance weight table and used for being matched with the resonance points by replacing balance weights; and the plate clamp is detachably assembled with the clamp assembly and is used for detecting cracks generated in the test process of the test sample. The device can replace manpower to flexibly adjust the counterweight, realizes rapid and convenient operation, can timely detect a cracked plate in a test, and is convenient to timely stop the test before the sample is fractured.

The utility model discloses a surface acoustic wave device and a radio frequency front-end module. The surface acoustic wave device comprises an interdigital transducer, wherein the interdigital transducer comprises a first bus bar and a second bus bar which are oppositely arranged, an electrode finger and a plurality of gap electrodes; in the extending direction of the electrode fingers, an overlapping area is formed between the first bus bar and the second bus bar, a first area is formed between the overlapping area and the first bus bar, a second area is formed between the overlapping area and the second bus bar, and the first area and the second area are adjacent to the first bus bar and the second bus bar respectively; the plurality of gap electrodes are arranged in at least one of the first area and the second area, and the plurality of gap electrodes, the bus bars and the electrode fingers are arranged at intervals; wherein the plurality of gap electrodes form a first curve in the arrangement direction of the electrode fingers. According to the invention, the Q value near the anti-resonance point can be improved while the inhibition effect of the transverse mode is improved.

The invention belongs to the technical field of machining, and particularly relates to an ultrasonic internal broaching test platform and an ultrasonic vibration mode control method.The test platform comprises a base, a broach and a clamping mechanism, and the clamping mechanism comprises a supporting ring and a clamping sleeve; a clamping groove is formed in the broach, and a protrusion matched with the clamping groove is arranged on the clamping sleeve. A plurality of supporting columns are arranged on the base, and the supporting columns are arranged in a circular shape. The broach is arranged in a space defined by the multiple supporting columns. And a piezoelectric actuator is arranged on the broach. Based on the platform, the invention provides the control method of the ultrasonic vibration mode, modal drift can be optimized and reduced by adjusting the pre-tightening force and the ultrasonic power supply driving frequency, the pre-tightening force is adopted to adjust and stabilize the contact rigidity, and the energy loss can be reduced; through frequency tracking, resonance points are matched in real time, and energy transfer can be maximized; the two modes are cooperatively controlled, response speed and stability are both considered, and the method adapts to high-dynamic loads.

The invention discloses a broadband wearable double-frequency filtering antenna with an independent and controllable radiation zero point, and the antenna employs a double-layer dielectric substrate structure, the upper layer is a Rogers4350B substrate, the lower layer is a flexible felt substrate, and a multi-structure coupling design of a T-shaped strip, a U-shaped groove, a rectangular groove and a parasitic strip is integrated through a rectangular radiation patch. And dual-frequency work and radiation zero independent regulation and control are realized. Wherein the T-shaped strip generates a dual-frequency characteristic and a first radiation zero point between two frequency bands; the U-shaped groove regulates and controls the low-frequency zero point and broadens the low- The rectangular groove introduces a second radiation zero point between two frequency bands and expands the high-frequency bandwidth; a high-frequency zero point and a new resonance point are introduced into the parasitic strip, and the high-frequency matching bandwidth is widened. The antenna has the flexible wearable characteristic, the broadband performance and the independent controllable characteristic of the radiation zero point, and is suitable for wireless communication scenes such as WiMAX / WLAN and the like.

The invention discloses a spiral resonance photoacoustic cell and an operation method, the spiral resonance photoacoustic cell comprises a gas chamber straight tube, a spiral tube, an optical fiber collimator and an optical fiber F-P sonic sensor, the two ends of the gas chamber straight tube are open, the two ends of the spiral tube are communicated with the gas chamber straight tube, an acoustic resonance point is formed at the center of the spiral tube, and the optical fiber F-P sonic sensor is arranged in the central area of the spiral tube; and the optical fiber collimator is arranged at one end of the air chamber straight pipe. The spiral pipe is wound outside the air chamber straight pipe, the spiral pipe is communicated with the air chamber straight pipe, the structural design of the spiral pipe enables the spiral pipe to form acoustic resonance at a specific frequency, and the optical fiber F-P sonic sensor obtains a photoacoustic signal; compared with a conventional resonance photoacoustic cell, the physical volume of the resonance photoacoustic cell is greatly compressed, and the system integration level is effectively improved. More importantly, under the condition that a compact appearance similar to that of a non-resonant photoacoustic cell is kept, the device amplifies the photoacoustic signal intensity by several times through an acoustic resonance effect, and the detection sensitivity and the signal-to-noise ratio of the system are remarkably improved.

The invention discloses a ripple resonance point vibration adding test method, device and equipment of a vehicle electric drive system, and relates to the technical field of intelligent automobiles, and the method comprises the steps: controlling a vehicle to operate under a plurality of different real vehicle working conditions, testing the whole vehicle high-voltage inner reticulate wave of the vehicle, and obtaining the high-voltage inner reticulate wave of the vehicle; obtaining whole vehicle ripple data corresponding to each real vehicle working condition; impedance testing is conducted on the electric driving system of the vehicle, and the resonant frequency of the electric driving system is determined based on obtained impedance data; the method comprises the following steps: carrying out initial test on an electric driving system, carrying out initial test on the electric driving system, and obtaining basic test data of the electric driving system; in the process of controlling the electric driving system to perform fixed-frequency operation according to the resonant frequency, inputting a ripple signal to the electric driving system based on the whole vehicle ripple data to obtain resonance point vibration adding test data of the electric driving system; and analyzing the basic test data and the resonance point vibration adding test data to obtain a resonance point vibration adding test evaluation result of the vehicle.

The invention discloses a capacitor loss angle determination method and device, a storage medium and computer equipment, and the method comprises the steps: carrying out the coarse frequency scanning of a measurement loop based on a logarithmic frequency step length, and determining a resonance region based on the change rate of the impedance amplitude of the measurement loop; performing fine frequency scanning on the measurement loop based on the linear frequency step length in the resonance area; determining a resonance peak based on the impedance amplitude of a frequency point in the resonance area; determining resonance attribute information of the resonance peak; selecting a reference frequency point in a preset area around the resonance peak based on the resonance attribute information; determining an initial resonance point frequency of the measurement loop, and compensating the initial resonance point frequency to obtain a resonance point frequency; determining a resonance type and a corresponding loss angle determination mode, determining initial circuit parameters, and performing error compensation on the initial circuit parameters in real time to obtain circuit parameters; and based on the circuit parameters and the resonance point frequency, determining the capacitor loss angle by using a loss angle determination mode.

The invention relates to the technical field of electronic measurement and sensing, and discloses a capacitance monitoring method and system based on a sweep frequency resonance point, and the method comprises the steps: carrying out the coarse sweeping in an initial frequency range, obtaining an impedance spectrum, and recognizing a coarse resonance interval; carrying out fine scanning in the interval and calculating an accurate resonant frequency by adopting a quadratic interpolation method; calculating a capacitance value in combination with the mapping table; and dynamically adjusting the frequency sweeping window of the next period based on the historical resonant frequency. The system comprises an excitation signal generation unit, an impedance response acquisition unit, a coarse / fine scanning control unit, a resonant frequency calculation unit, a capacitance resolving unit and a dynamic frequency window updating unit, and integrates a temperature compensation and anomaly detection mechanism. Through the two-stage frequency sweeping and self-adaptive frequency window strategy, the monitoring period is shortened to 1 / 5 or below of that of a traditional method while it is guaranteed that the resonant frequency measurement precision is superior to 0.01 Hz, and the real-time performance, stability and environmental adaptability are remarkably improved.

The invention discloses a broadband double-layer interconnection structure based on a silicon adapter plate technology, and belongs to the technical field of radio frequency microsystems. According to the method, a three-dimensional compensation structure is formed by adding square conductive metal and TSVs into lower-layer metal at one end, close to a transition structure, of an original coplanar waveguide transmission line, and a resonance point with return loss of-51dB is introduced at 17.59 GHz, so that the broadband interconnection effect that the return loss of 0-33GHz is smaller than or equal to-20dB is achieved, and the in-band insertion loss fluctuation value is reduced by 11.6% compared with that of the original structure. Compared with a traditional interconnection structure broadband design, the method has the advantages that on the premise that the plane area is not increased, the broadband interconnection design difficulty is greatly reduced through the three-dimensional structure design.

The utility model discloses an ultrasonic beauty instrument based on multi-feedback automatic adjustment. The ultrasonic beauty instrument comprises a transducer, a drive circuit, a single chip microcomputer, an alternating current impedance detection unit, a temperature detection unit and a voltage and current detection unit. The skin impedance is detected through the alternating current impedance detection unit, the output of the driving circuit is adjusted, and then the ultrasonic intensity of the transducer is adjusted; the skin surface temperature is detected through the temperature detection unit, when it is detected that the skin temperature reaches a threshold value, output of ultrasonic waves is stopped, and a user is protected from being scalded; an output ultrasonic signal is monitored in real time through the voltage and current detection unit to adjust the frequency of an ultrasonic excitation signal output by the driving circuit, so that the transducer works on a resonance point all the time, automatic frequency tracking is achieved, and the accuracy of the output ultrasonic power is improved. Therefore, frequency tracking is carried out through multiple feedback modes of voltage and current detection, temperature detection and alternating current impedance detection, and the ultrasonic output intensity is automatically adjusted, so that a better use effect is achieved, and the use experience of a user is improved.

The invention discloses a digital system power distribution network impedance optimization method and system, and the method comprises the following steps: S1, obtaining the frequency-varying parasitic parameters Jg (f), Jr (f) and Jz (f) of a digital system power supply through a vector network analyzer, and enabling f to be a frequency variable; s2, calculating a dynamic matching coefficient DsC based on the frequency-varying parasitic parameter, and calling a PDN decoupling scheme set from a decoupling scheme database according to a DsC matching interval; s3, inputting the PDN decoupling scheme set into ADS software for segmented variable step size impedance simulation, wherein the step size of the frequency band from 1 MHz to 100 MHz is 0.5 MHz, and the step size of the frequency band from 100 MHz to 3 GHz is 5 MHz; and generating a surface-mounted PCB decoupling index DI containing a resonance penalty term and a micro-system substrate decoupling index WI. According to the method, the high-frequency resonance suppression capability is improved, frequency change parasitic parameter extraction is combined with resonance point penalty term design, impedance peak fluctuation is compressed to be within + / -8% of a target value in a 1-3GHz frequency band, and actually measured power supply noise of a 10Gbps SerDes interface is reduced by 62%.

The invention provides a resonance control method for an excimer lamp driven by a steep pulse edge, and relates to the technical field of molecular lamps. The resonance control method of the excimer lamp driven by the steep pulse edge comprises the following steps: S1, based on a dielectric barrier discharge equivalent circuit model, adopting a fast Fourier transform spectrum analysis method, measuring fundamental wave impedance characteristics of an LC resonance network through an impedance analyzer, establishing a transfer function containing parasitic parameters: Z (s) = [sLr + 1 / (sCr)] Rarc, and generating an initial resonance parameter set; by establishing a transfer function model containing parasitic parameters, combining fast Fourier transform spectrum analysis and accurately extracting fundamental wave impedance characteristics, the problem of resonance point offset caused by neglecting the parasitic parameters in a traditional method is solved, the precision of an initial resonance parameter set is improved, real-time phase difference data are identified on line by using a recursive least square method, and the real-time phase difference is obtained. Resonant frequency changes are dynamically tracked, frequency drift errors are compensated, resonance point tracking precision is controlled within + / -0.1%, and invalid discharge energy loss is remarkably reduced.

The invention discloses an antenna design method integrated with a two-dimensional structure balancer. The two-dimensional structure balancer is composed of a feed cable and a simulation cable, wherein the feed cable and the simulation cable are bent along a characteristic line of a two-dimensional oscillator and attached to the surface of the two-dimensional oscillator. According to the invention, a low-frequency resonance point can be introduced without adding any load or disturbance, the lower limit working frequency of the antenna is expanded, and the broadband performance is realized. The broadband performance is realized, and only the horizontal polarization component is excited when the antenna is horizontally arranged. The antenna is simple in structure, low-frequency resonance points can be introduced without additional loading or disturbance, broadband performance is achieved, the original size of the antenna is kept, the antenna has the advantage of miniaturization, and the antenna is easy and convenient to manufacture and high in cost effectiveness. The antenna array can also be used for an oscillator antenna with any two-dimensional convex boundary shape, an antenna array unit can be designed and arrayed according to the scheme, the antenna array unit is expected to be further designed and used for all communication frequency bands, and the antenna array unit has wide application prospects in high-speed data transmission scenes such as low-altitude service and everything intelligent connection.

The invention discloses a manufacturing method, a process module matching method and a substrate processing device. The manufacturing method includes: a device setting operation of matching resonance points of a first process module and a second process module different from the first process module to each other; a first substrate processing operation of processing the substrate in the first process module and / or the second process module; and a resonance frequency control operation of adjusting a resonance point of the first process module and the second process module, which is changed in a case where the first substrate processing operation is performed, to an initial resonance point, the resonant frequency control operation includes controlling at least one of a variable element of a first resonant control circuit of the first process module and a variable element of a second resonant control circuit of the second process module to adjust a resonance point of the first process module and the second process module to an initial resonance point.

The invention discloses a millimeter wave broadband dual-polarization magnetoelectric dipole antenna. The antenna comprises a first dielectric plate, a first bonding layer, a second dielectric plate, a second bonding layer, a third dielectric plate and a metal floor which are sequentially arranged from top to bottom, the upper surface of the first dielectric plate is provided with a group of electric dipoles used for radiating electromagnetic waves, a feed structure and a metal patch, and magnetic dipoles are arranged between two adjacent layers of the first dielectric plate, the first bonding layer, the second dielectric plate, the second bonding layer and the third dielectric plate. A first metal column unit used for moving out of a matching abnormal resonance point in a working frequency band is arranged between the first dielectric plate and the first bonding layer. According to the invention, millimeter wave frequency band, wide bandwidth performance, compact structure and multi-polarization characteristic can be integrated in one antenna, so that the requirements of wireless communication on high speed, low cost, large coverage, good anti-interference capability and the like can be met.

A passive near-field communication device, method and apparatus. The device comprises a wake-up tuning coil, a communication antenna coil and an NFC chip, wherein a resonance point of the wake-up tuning coil is the same as a carrier frequency band of a card reading device; and the communication antenna coil is connected to the NFC chip in series and is tuned to the carrier frequency band of the card reading device.

A plastic integrated three-dimensional broadband dual-polarized antenna unit comprises a plastic substrate, a radiator and a feed structure, the radiator comprises a main radiator and a coupling resonator, the main radiator comprises four radiation arms, the four radiation arms and the plastic substrate form a first angle to form a three-dimensional structure body, and the coupling resonator is arranged on the plastic substrate. The first angle is larger than 0 degree and smaller than 90 degrees, the coupled resonator is arranged above the main radiator, and the main radiator is electrically connected with the feed structure; the coupled resonator and the main radiator are coupled to generate a first resonance point, and two radiation arms, located on a diagonal line, in the four radiation arms are combined to form two pairs of radiation arms and feed through corresponding feed structures to respectively generate a first polarization direction radiation signal and a second polarization direction radiation signal which are orthogonal to each other. Radiation signals generated by the two pairs of radiation arms correspond to a second resonance point, and a third resonance point is generated between the two pairs of radiation arms through coupling.

The invention belongs to the technical field of cable insulation material aging detection, and relates to a cable aging degree judgment method based on an impedance spectrum and a related device. The method comprises the steps of obtaining a reflection coefficient curve based on an impedance spectrum curve; obtaining a reflection coefficient real part curve based on the reflection coefficient curve, and extracting a resonant frequency corresponding to a resonant point of the reflection coefficient real part curve; calculating a relative dielectric constant real part of an insulating medium of the cable to be measured under different resonant frequencies; outputting an attenuation constant curve based on the reflection coefficient curve and a cable reflection coefficient amplitude calculation model; extracting a plurality of attenuation constant values of the attenuation constant curve on the resonant frequency; substituting the attenuation constant value and the relative dielectric constant real part into a dielectric loss angle tangent value calculation model to obtain a dielectric loss angle tangent value of the to-be-measured cable under the resonant frequency; and carrying out aging degree judgment based on the dielectric loss angle tangent value. The problem that an existing method is long in time consumption or cannot acquire full-band dielectric information of a cable insulating material is solved.

The invention discloses a frequency selective surface performance prediction method and related equipment. The method comprises the following steps: constructing a pre-training data set; constructing a variational auto-encoder model, and extracting potential common features of a performance curve by using a variational auto-encoder as a generative model; training a variational auto-encoder model by using the pre-training data set; preprocessing the data of the target frequency selective surface scene, extracting resonance characteristics of the performance curve, and obtaining a characteristic data set; constructing a resonance sensing variable-length proxy model; and sampling the characteristic data set to train a resonance sensing variable-length proxy model, and using the trained model to predict the performance of the frequency selective surface. According to the method, physical priori knowledge is embedded in the agent model training process to improve the curve representation capability, a resonance point sensing curve generation mechanism is introduced, the physical consistency modeling and high-quality reconstruction of the performance curve are realized from the resonance point characteristics of the curve, and the expression capability of the model to the complex resonance characteristics is remarkably improved.

The invention discloses a multi-frequency resonance point absorption type sea wave energy conversion device and a control method. The device comprises a fixed base, a sea wave energy absorption mechanism, an energy conversion mechanism, a variable stiffness mechanism and a power generation mechanism. An energy conversion mechanism, a variable stiffness mechanism and a power generation mechanism are mounted in the fixed base, and the variable stiffness mechanism and the power generation mechanism are connected with the energy conversion mechanism; one end of the sea wave energy absorption mechanism is arranged in the fixed base in a penetrating mode, and the end, arranged in the fixed base in a penetrating mode, of the sea wave energy absorption mechanism is connected with the energy conversion mechanism. According to the point absorption type sea wave energy conversion device, a new thought for improving the energy capture efficiency is provided, the spring force output by the spring is adjusted through the variable stiffness mechanism, and the stiffness of the whole sea wave energy capture device is changed through real-time adjustment of the spring force; therefore, the floater can be matched with the dominant frequency of the sea waves in a certain frequency band to generate resonance, and the capturing efficiency of the sea wave energy is further improved.

The invention provides a vibration reduction method and device for a vertical condensate pump. The vertical condensate pump aims at accurately adjusting resonance points, reducing vibration hazards and improving the running stability of the vertical condensate pump. The vibration reduction method of the vertical condensate pump is applied to the vibration reduction device, and the vibration reduction device comprises a motor, a controller, a fixing support and a lead screw. Acquiring the real-time rotating speed of the vertical condensate pump; on the basis that the real-time rotating speed is matched with a target rotating speed in a preset information base, a vibration reduction adjusting scheme of the vertical condensate pump at the target rotating speed is stored in the preset information base, and the vibration reduction scheme is used for controlling a vibration reduction device to adjust the supporting force of a lead screw for supporting the vertical condensate pump at the target rotating speed. The amplitude data corresponding to the resonance point of the vertical condensate pump is adjusted to be within the corresponding standard amplitude data range; and if the matching is consistent, determining a motor control instruction based on the corresponding vibration reduction adjustment scheme, and sending the motor control instruction to the controller.

The invention provides an inverter control method and system and a photovoltaic inverter, and belongs to the technical field of inverter control. The method comprises the following steps: firstly, analyzing a sampling signal in an inverter to obtain a plurality of frequency domain signal points; then, one or more target resonance points are determined from the multiple frequency domain signal points, filtering parameters are determined according to the frequencies of the target resonance points to obtain a band-pass filter, the sampling signals are filtered through the band-pass filter, and signal components corresponding to the target resonance points are obtained; and finally, obtaining a virtual damping output quantity according to the target resonance point and the signal component corresponding to the target resonance point, and controlling the inverter according to the virtual damping output quantity. Therefore, targeted resonance suppression is carried out on each target resonance point, so that the performance of the inverter is improved.

The invention relates to the technical field of impedance measurement, in particular to an impedance measurement method and system for a common-mode inductor, and the method comprises the steps: obtaining voltage and current signals of the common-mode inductor in a test circuit, and obtaining frequency domain response atlas data containing impedance characteristics through time-frequency transformation; carrying out non-linear segmentation division on the frequency axis to form a plurality of frequency segmentation regions; extracting the phase amplitude of each segmented region, carrying out clustering segmentation, and recognizing an effective impedance frequency band; analyzing phase synchronization characteristics in the effective impedance section, and determining a common-mode resonant frequency point through clustering analysis; and fusing multi-section frequency region division, effective impedance section and resonance point information to finish accurate measurement of the impedance characteristic of the common-mode inductor. According to the method, through non-linear scanning and phase information joint analysis, the recognition precision of impedance response key characteristics in a broadband range is improved, the capturing capacity of parasitic parameters and resonance behaviors is enhanced, and efficient and high-precision comprehensive evaluation of the impedance characteristics of the common-mode inductor is achieved.

The present application provides a new type of brushless high speed motor, in which the integrated shell and air duct are separately fixed to the outside of the inner hole column, the material of the air duct and the outer shell is BMC, and the material of the inner hole column is metal. The two parts are combined and configured to be made of different materials, which can effectively buffer and reduce the resonance point of the motor, and reduce the noise caused by the high speed rotation of the motor. In addition, the housing is configured as a split type, and the air duct and shell can be directly fixed outside the inner hole column by BMC injection molding, which reduces the processing technology, reduces the burr of the housing. A grounding post is provided on the outside of the stator package for grounding.

The embodiment of the invention provides a harmonic control method and device of an electric power system and a storage medium, the electric power system comprises a converter for converting direct current into alternating current, and the method comprises the following steps: determining a frequency range of a resonance point of the electric power system; under the condition that the switching frequency of the converter falls into the frequency range, determining a target resonant frequency of the resonant point; determining the type and electrical parameters of a nonlinear device needing to be added by taking the target resonant frequency as an optimization target; and setting the non-linear device in the power system. According to the method, a relatively serious resonance point in a power system is identified, and the vibration frequency of the resonance point of the power system is changed in a mode of increasing a nonlinear device, so that the frequency point of an original resonance source in a circuit is avoided, and the harmonic problem in a specific scene is solved in a low-cost mode; and long-term stable operation of a power system can be ensured.

The lens antenna is provided in the glasses, and includes a feed sheet and an annular region. The feed sheet is configured to perform excitation feeding in the first frequency band to excite the annular region to produce a first resonance point. A capacitive coupling gap is provided between the annular region and the feed sheet. The annular region is provided around the edge of the lens, and a first gap provided at a designated position of the annular region. The feed sheet is fixed to the edge area of the lens.