22 results about "Resonance point" patented technology

The application relates to the technical field of ultrasonic waves, in particular to an ultrasonic generator based on frequency real-time scanning tracking and a working method thereof. The application provides the ultrasonic generator based on frequency real-time scanning tracking and the working method thereof, when a cutting (grinding) load changes, the ultrasonic generator simultaneously scans the frequency and adjusts the air gap length to obtain an optimal resonance point. Through the method, slight deformation or displacement caused by factors such as temperature, humidity and mechanical vibration can be automatically offset, stable work is maintained, and the environmental adaptability is enhanced. The application aims at solving the technical problems of greater loss and greater heat of an ultrasonic transducer in the prior art.

The application further provides a handheld personal assistant device antenna device, and specific technical solutions are as follows: a processor and an antenna end shared by a radio frequency identification ultra-high frequency linear antenna and a diversity antenna; an antenna tuner used for receiving a control signal of the processor, switching a resonance point, and adapting an operating frequency of the ultra-high frequency linear antenna or the diversity antenna; a radio frequency switch module connected with the processor through a first control interface and connected with the antenna end through a plurality of radio frequency channels, and used for switching a radio frequency channel state of the radio frequency identification ultra-high frequency linear antenna and the diversity antenna. The application realizes antenna multiplexing of the radio frequency identification ultra-high frequency linear antenna and the diversity antenna through a switch and an interface, reduces the number of antennas required by a mobile device and hardware cost, improves product competitiveness, and enhances product practicability.

The application provides a radome based on broadband wave-absorbing and wave-transmitting integrated metamaterial, which comprises a wave-absorbing part and a frequency selection part, the wave-absorbing part comprises a fourth metal layer and a fifth metal layer, the fourth metal layer and the fifth metal layer comprise filter prongs and lumped resistors; the frequency selection part is located on the inner side of the wave-absorbing part, and the frequency selection part comprises a first metal layer, a first dielectric layer, a second metal layer, a second dielectric layer and a third metal layer arranged in sequence. The radome based on broadband wave-absorbing and wave-transmitting integrated metamaterial has three independent resonance points in the wave-transmitting frequency band by arranging the wave-absorbing part and the frequency selection part, and forms a radome with the band-pass filter characteristics of the third-order resonance characteristics; meanwhile, the radome can efficiently absorb electromagnetic waves in the low frequency band, effectively reduces the radar scattering cross section of the radome double war (multi-station), and improves the stealth performance; and the structural unit size of the radome metamaterial is small, the unit size is only three tenths of the working wavelength, and the radome has good angle stability.

The application provides a method for inversely deducing the length of a PCB back-drilling stub by using signal integrity test parameters.The method comprises the following steps: S1, acquiring the electrical signal propagation speed of a to-be-tested PCB transmission line; and S2, collecting the insertion loss curve of the transmission line.The application provides a method for inversely deducing the length of a PCB back-drilling stub by using signal integrity test parameters, which inversely deduces the length of the stub by acquiring the S21 curve through electrical signal test, does not need to slice and sample the PCB, avoids the physical damage of the micro-slicing method to the PCB, retains the integrity and use value of the measured PCB, greatly reduces the detection cost, realizes nondestructive detection, can accurately identify the resonance characteristics generated by the small stub by analyzing the resonance point frequency on the insertion loss curve, has higher detection precision and stronger reliability, and guarantees the detection precision.

This application discloses an electronic pipa, comprising: a soundboard, a headband, and a pickup. The body is mounted on the outer rear end of the soundboard, and a headstock is fixedly mounted on the top of the body. A tuning peg is inserted into the headstock. A headband is fixedly mounted on the lower front end of the soundboard, and a string is threaded through the headband. A pickup is fixedly mounted inside the lower end of the body by screws, and a pickup bar is connected to the front end of the pickup. This application belongs to the field of pipa technology. The purpose of this application is to solve the problems in existing technologies where the original sound of the pipa cannot be effectively amplified, and where it is often difficult to ensure the aesthetics of the installation process and the optimal resonance point within the body when installing the pickup. The achieved technical effect is: solving the problems of not being able to effectively amplify the original sound of the pipa, and the difficulty in ensuring the aesthetics of the installation process and finding the optimal resonance point when installing the pickup.

This invention discloses a vibration suppression method, control board, device, and storage medium. The invention relates to the field of vibration reduction technology for motion tables. The method includes: a first processor acquiring motion data of a support platform, preprocessing the motion data, and sending the preprocessed motion data to shared memory; a second processor acquiring motion data of the motion table and obtaining the preprocessed motion data from the shared memory; the second processor performing a Fourier transform on the motion data of the motion table and the preprocessed motion data of the support platform to obtain transformed data, and determining the resonance point of the motion table and the support platform based on the transformed data; the second processor determining the damping force of the motion table based on the resonance point of the motion table and the support platform, and using the damping force to counteract the force on the motion table to suppress the vibration generated by the motion table.

The present disclosure belongs to the technical field of hybrid DC power transmission system stability, and particularly relates to a hybrid DC instability discrimination method and system based on mode resonance, comprising: establishing a full-order state space model of a hybrid DC power transmission system, constructing a system dynamics model under the time scale of a DC control system, linearizing the obtained system dynamics model to obtain a linearized model of the hybrid DC power transmission system; calculating eigenvalues of the linearized model and participation factors of the eigenvalues, screening an alternative resonance mode set according to the obtained eigenvalue distribution, and system parameters strongly related to the alternative resonance mode set; modifying system parameters of the hybrid DC power transmission system, drawing root loci of system eigenvalues, judging whether mode resonance occurs and determining resonance strength of the mode resonance; if mode strong resonance occurs and the resonance strength is greater than a set threshold, it is determined that the system will be unstable, and system parameters at the resonance point are recorded.

This invention discloses an atomization control method, device, and system, relating to the field of electronic atomization technology. It aims to solve the technical problems of battery overload in ultrasonic atomization devices due to chasing the highest resonance point, and the mismatch between actual output power and atomization demand. This invention determines the target power based on the power range defined by the safe power threshold of the power supply system and the atomization demand. It determines the adjustment step of the driving frequency based on the difference between the current power and the target power, and combines the current power and the target power, as well as the relationship between the current power and the driving frequency from the previous moment, to determine the frequency adjustment direction. This allows for the adjustment of the driving frequency of the vibration control circuit of the ultrasonic atomizing plate to bring the power of the ultrasonic atomizing plate closer to the target power. This invention reduces battery load and extends its lifespan, achieves matching of system power output with the atomization demand, and significantly improves the stability of the ultrasonic atomization system.

This invention discloses a method for assessing the severity of transmission line resonance based on a harmonic circular arc model, relating to the field of power system technology. The method includes the following steps: single-end harmonic data acquisition, construction of a harmonic circular arc model, calculation of three major assessment indicators, risk level classification of the indicators, resonance severity rating, and resonance point location. This invention only requires single-end harmonic measurement to construct full-line harmonic constraints, eliminating the need for multi-point monitoring and complex impedance modeling, significantly reducing costs and enhancing engineering operability. The design of three major assessment indicators enables multi-dimensional quantification of resonance state, aligning with national and enterprise standards, and solving the problem of traditional methods' difficulty in accurately quantifying resonance severity. A risk matrix is ​​used to classify seven risk levels and accurately locate resonance points, overcoming the limitations of traditional methods that cannot locate them. The method integrates assessment, identification, and location, significantly improving the efficiency and accuracy of resonance assessment, and providing reliable technical support for line operation and maintenance and suppression measures.

The application provides an electronic device, comprising a reference floor and an antenna unit, the antenna unit comprising an antenna radiator, a feed source and a resonance circuit, the antenna radiator being arranged at one side of the reference floor, the antenna radiator comprising a first free end, a second free end and a feed point, the feed point being electrically connected to the feed source, and a normal projection of the feed point on the reference floor being located in a target area of the reference floor, the feed source being used to excite the antenna radiator to generate a target resonance mode supporting a target frequency band, and used to excite the reference floor to generate a target characteristic mode supporting the target frequency band, the target characteristic mode forming a current weak area in the target area, the resonance circuit being electrically connected between the feed point and the feed source, and the resonance circuit being used to change an impedance matching state between the antenna radiator and the feed source, so that a plurality of impedance matching resonance points are formed between the antenna radiator and the feed source in the target frequency band. The electronic device provided by the application can realize switchless, and the communication performance is stable.

This invention discloses a visual automatic frequency tracking vibration polishing machine, relating to the field of intelligent control of precision polishing equipment. The polishing machine includes an electromagnetic circular vibrating base, a material cylinder assembly, several inclined elastic springs, a housing assembly, an adjustable frequency and voltage vibration power supply, and a visual automatic frequency tracking module. The visual automatic frequency tracking module includes an image acquisition unit facing the liquid surface of the material cylinder, a supplementary lighting unit, a controller, and a communication interface connected to the vibration power supply. The controller dynamically adjusts the driving frequency and driving voltage based on the characteristics of the liquid surface image, enabling the polishing machine to operate stably at the optimal resonance point under the current load. Preferably, the elastic springs are made of bainitic steel; the housing assembly consists of a plastic shell, a silicone intermediate layer, and a metal base plate stacked to form a constraint layer damping structure. This invention overcomes the shortcomings of electrical feedback frequency tracking schemes in detecting abnormal sample-level movements, improving polishing consistency and efficiency.

The application discloses a structural displacement response topology optimization design method and device, and relates to the technical field of structural dynamics. The method comprises the following steps: a finite element model of a structure is established, boundary conditions and external load excitation are applied, an optimization model with the minimum displacement amplitude as the target and the volume fraction and the anti-resonance frequency as the constraints is constructed, after the parameter initialization is completed, the sensitivities of the displacement amplitude and the volume fraction are iteratively calculated, the anti-resonance frequency eigenvalue sequence is solved by using the modal acceleration method, the constrained anti-resonance frequency is tracked in combination with the modal assurance criterion, the sensitivities of the anti-resonance frequency to the design variables are solved by using the Moore-Penrose generalized inverse, all the parameters and the sensitivities are input into the MMA optimization algorithm, the convergence is judged, and if the convergence is satisfied, the iteration is terminated to obtain the optimal design variable vector, and the structural displacement response topology optimization is realized. The method solves the problem that the existing technology is prone to falling into the anti-resonance point and converging in advance to form an intermediate density gray area when displacement minimization topology optimization is performed.

While achieving resonance suppression, allocation of filters is determined in a manner that satisfies a constraint on the number of filters. A control assistance device that performs assistance for setting a plurality of first filters provided in a servo control device that controls a motor, the control assistance device including: a resonance detection section that detects a plurality of resonance points in a frequency characteristic of an input-output gain and a phase lag of an input and an output of the servo control device measured from an input signal and an output signal that vary with frequency; a filter setting section that sets a plurality of second filters that exceed the number of the plurality of filters in order to suppress the plurality of resonance points; and a grouping section that groups the plurality of second filters to set the plurality of first filters.

The utility model provides a kind of band-pass filter and radio frequency front end module, wherein the band-pass filter includes dielectric substrate, respectively pastes and is fixed in the dielectric substrate and is located the first microstrip transmission line of same plane, second microstrip transmission line, first resonator, second resonator and third resonator;The first resonator includes first microstrip patch fragment, second microstrip patch fragment, third microstrip patch fragment, first bending microstrip patch fragment, second bending microstrip patch fragment, fourth microstrip patch fragment, fifth microstrip patch fragment, sixth microstrip patch fragment;The second resonator includes first microstrip structure and second microstrip structure;The third resonator includes third microstrip structure.The band-pass filter of the utility model not only can produce three resonance points, and also can reduce overall size, so that it meets miniaturization demand.

The application discloses a kind of based on sideband harmonic excitation's double-unit motor modal parameter identification method, belong to motor field.This method includes selecting the sideband harmonic current of preset frequency as vibration excitation source;Select the maximum speed of sideband harmonic current as test speed;Switching frequency sweep is carried out to double-unit motor to be measured, and the vibration acceleration data of each test point is obtained;Different phase shift angles are used to carry out carrier phase shift processing to sideband harmonic, and the vibration acceleration data of each test point in different order is obtained by repeating test step;Select multiple suspicious resonance points from vibration acceleration data;According to corresponding vibration acceleration data, mode shape analysis is carried out, and the spatial mode shape, vibration order and natural frequency of real resonance point are confirmed;According to real resonance point, frequency response function is constructed, and the modal parameter of double-unit motor to be measured is extracted from it.The modal parameter identification of low cost, high excitation energy and wide frequency range is realized.

The application discloses a high-frequency special power resonance point avoidance control system and method, and relates to the field of special power control. The system comprises a power supply unit, a first current collection unit for collecting a first current signal flowing through a parasitic inductor, a second current collection unit for collecting a second current signal flowing to a load, a voltage collection unit for collecting a load end voltage signal, a virtual damping compensation module for multiplying a difference between the first current signal and the second current signal by a virtual damping coefficient to obtain a damping voltage, and then summing the damping voltage with the load end voltage signal to obtain a feedback voltage, and a voltage control module for comparing and adjusting the feedback voltage with a reference voltage. By introducing a virtual damping voltage at the control algorithm level, a virtual resistor is equivalent to being connected in series with the capacitor, the resonance peak value is reduced, the phase is improved from step lag to smooth transition, the system stability and robustness are improved, and physical devices need not be added to avoid heat loss.

The application provides a waveguide device, a microwave outdoor unit and a microwave distance transmission device, and relates to the technical field of communication. The waveguide device comprises a cavity, a cover plate, a ridge structure, a ferrite, a permanent magnet and a tuning piece. The cavity comprises opposite first and second surfaces, and the first surface is provided with a chamber. The cover plate is arranged on the first surface of the cavity and covers the chamber. The ridge structure is arranged in the chamber, the ferrite is arranged on the ridge structure, and the permanent magnet is arranged on the second surface of the cavity. The tuning piece is arranged on the ridge structure, the tuning piece is spaced apart from the ferrite, the top surface of the tuning piece away from the second surface is higher than the top surface of the ridge structure away from the second surface, the tuning piece is coupled with the ridge structure, the tuning piece can introduce an in-band resonance point, the effect of multiple resonances is achieved, the working frequency of the device can be adjusted, and the bandwidth of the working frequency can be widened. The waveguide device can be applied to the microwave outdoor unit or the microwave distance transmission device to realize one-way transmission of radio frequency signals.

The application belongs to the technical field of wireless communication, and relates to a directional coupler, and particularly provides a Chebyshev multi-hole coupler based on a tapered height-reducing waveguide, which is used to solve the high-frequency resonance problem of a traditional Chebyshev multi-hole coupler. On the basis of the traditional Chebyshev multi-hole coupler, the main waveguide and the auxiliary waveguide adopting the standard waveguide are replaced by the tapered height-reducing waveguide structure, so that the waveguide height and the coupling hole size are inversely proportional to each other and matched, the high-frequency resonance point of the coupler is eliminated through the matching, the high-frequency resonance problem of the traditional Chebyshev coupler is solved, the working bandwidth of the coupler is widened, and the performance of the coupler is further improved.

The present disclosure discloses a method, a controller, and a motor drive system for suppressing electromechanical coupling resonance, relates to the technical field of electromechanical control. The present disclosure includes constructing a dynamic model of a mechanical system; constructing a control algorithm model of a control system: determining a mathematical model of a control object in the control system, including a mathematical model of a permanent magnet motor and an inverter, and designing a motor controller for the mathematical model; constructing an electromechanical coupling model based on the dynamic model of the mechanical system and the control algorithm model of the control system; and carrying out resonance characteristic analysis of an electromechanical system based on the electromechanical coupling model to determine resonance points. The method proposed in the present disclosure combines ADRC, ensuring good control performance when motor parameters change, and robustness against changes of PMSM parameters.

The invention belongs to the field of rail transit, and particularly relates to an intermediate resonance circuit detection method, system and device and a storage medium, and the method comprises the steps: enabling an upper computer to be connected with a TCU case, sending a starting instruction to the TCU case to detect whether a secondary resonance point of an intermediate resonance circuit deviates or not, the detection process is as follows: according to the working state and the working power of the intermediate resonant circuit, obtaining intermediate voltage waveforms in a preset acquisition period under different working powers; according to the intermediate voltage waveform and a wave trap algorithm, a ripple voltage effective value under the preset working frequency is obtained; calculating a voltage deviation between the ripple voltage effective value and a standard voltage effective value, and judging whether the voltage deviation is within a preset deviation range or not; and if the voltage deviation is not within the preset deviation, determining that the secondary resonance point of the intermediate resonance circuit deviates. According to the invention, the converter does not need to be dismounted, and whether the secondary resonance frequency point shifts or not can be detected by using the hardware of the vehicle control cabinet.