16 results about "Higher order harmonics" patented technology

The invention discloses a permanent magnet synchronous motor current harmonic suppression method based on model prediction control, and the method comprises the following steps: S1, building a mathematical model of a permanent magnet synchronous motor in a rotating coordinate system, and carrying out the discretization through an Euler discretization method, and obtaining a prediction model for predicting the state of the permanent magnet synchronous motor at a future moment; s2, designing and constructing a cost function including a fundamental current tracking item and a high-order current harmonic suppression item in the prediction model; calculating a current harmonic term factor; s3, traversing voltage vectors corresponding to all switching states of the inverter, calculating predicted current and a cost function under the action of the voltage vectors, selecting an optimal voltage vector enabling the cost function to be minimum, and generating a switching signal to drive the permanent magnet synchronous motor to operate; according to the method, the prediction model containing fundamental wave tracking and high-order harmonic suppression is constructed, and the harmonic suppression factor is optimized in real time by using the Lagrange multiplier method, so that current harmonic suppression and system loss reduction are realized.

The invention relates to the technical field of motor control in the intelligent power grid industry, and discloses a space vector control method for a twelve-phase permanent magnet synchronous motor flywheel energy storage system, a control circuit of the flywheel energy storage system relates to power electronic components such as various semiconductor field-effect tubes, and the space vector control method is used for high-precision control of a motor. Comprising the steps of S1, twelve-phase space vector decoupling fault-tolerant control, S2, high-order harmonic energy recovery closed loop, S3, quantum annealing parameter optimization layer, S4, flux linkage adaptive observer network construction and S5, 18-dimensional switching vector table construction. According to the scheme, through multi-reference coordinate system transformation and a redundant phase reconstruction algorithm, rapid fault-tolerant response of the twelve-phase motor during a single-phase or two-phase fault is realized, a current path is dynamically recombined during the fault, a negative-sequence current compensation ring is combined, torque ripple is effectively suppressed, and the reliability of the motor is improved under a high-speed charging and discharging working condition. The harmonic distortion rate is detected in real time through the sliding window FFT, the bandwidth of the controller is adjusted, and the problem that the dynamic response of a traditional fault-tolerant strategy is insufficient is solved.

This invention relates to the field of general control or adjustment system technology, and discloses an adaptive adjustment system for the machining process of a laser cutting rotary table. The system includes: an adjuster that synchronously acquires C-axis angle and displacement data before machining and performs harmonic analysis to identify the harmonic parameters of the workpiece; the adjuster performs quality control decisions based on higher-order harmonics and generates a feedforward compensation model using first- and second-order harmonic parameters; during machining, the model is queried, and Z-axis focus compensation signals and C-axis angular velocity compensation signals are output in real time. This invention enables the control system to actively identify the true geometric model of the workpiece before machining. Its feedforward compensation based on the true model avoids the lag of traditional feedback control and ensures the stability of the machining process.

The application discloses a high-order overtone DOR measurement method, system, device and medium, relates to the technical field of information acquisition and processing, and comprises the following steps: performing local correlation processing on a carrier channel signal acquired through a satellite antenna to obtain interference phases in multiple first integral periods, and determining a first phase polynomial of a carrier model based on all the interference phases; determining a high-order overtone model based on the phase polynomial of the carrier model; correcting multiple high-order overtone signals acquired through the satellite antenna based on the high-order overtone model; determining a residual phase corresponding to each high-order overtone signal through the multiple corrected high-order overtone signals; and determining a DOR time delay observation corresponding to each high-order overtone signal through a multi-side tone DOR time delay calculation method based on the residual phase corresponding to each high-order overtone signal. The application can realize acquisition of a DOR measurement time delay observation, and has a wide application prospect in the field of deep space interferometric measurement.

The application discloses a magnetic resonance near-field super-resolution sensing unit with high-order harmonic suppression, comprising a first layer metal patch, a first dielectric substrate arranged in close connection with the first layer metal patch, a second layer metal ground arranged in close connection with the first dielectric substrate, a second dielectric substrate arranged in close connection with the second layer metal ground, and a third layer metal patch arranged in close connection with the second dielectric substrate; the first layer metal patch comprises a first sensing horizontal arm and a second sensing horizontal arm, wherein the first sensing horizontal arm and the second sensing horizontal arm are arranged in parallel and spaced apart, and a subwavelength slit is formed between the first sensing horizontal arm and the second sensing horizontal arm; the third layer metal patch comprises a microstrip feed line and a resonance structure, and the third layer metal patch is a symmetrical structure. According to the application, a good dynamic range and low loss are achieved, and the symmetrical structure can effectively suppress the influence of high-order harmonics and realize wide-spectrum operation.

The utility model provides a slotted rotor iron core and a scroll compressor, the slotted rotor iron core comprises an iron core body, the iron core body is provided with a slot part, and the slot part comprises a plurality of mounting slot groups and a plurality of magnet slots; on a horizontal projection, the plurality of magnet grooves are sequentially arranged at the edge of the iron core body at intervals along the circumferential direction of the iron core body, the plurality of mounting groove groups are arranged in one-to-one correspondence with the plurality of magnet grooves, and the mounting groove groups are arranged on the outer sides of the magnet grooves in the radial direction of the iron core body. The slotted rotor iron core can effectively reduce high-order radial force, and can reduce the density of high-order harmonic waves and optimize the harmonic waves of electromagnetic force through the mutual cooperation of the plurality of mounting groove groups and the plurality of magnet grooves; the installation groove group can reduce the cogging torque of the motor and enable the waveform of the motor to be close to a sine type in a wireless mode, the front cogging torque is improved, and vibration generated by the motor and high-order electromagnetic noise can be effectively reduced.

The invention provides a rapid detection device and method for evaluating the fatigue life of an aluminum alloy welding seam, and relates to the technical field of fatigue detection.The device comprises an ultrasonic excitation and acquisition module, a signal processing module and a signal processing module, the ultrasonic transducer is configured to inject a group of high-energy and continuous-frequency-sweeping ultrasonic excitation signals into a welding seam; the receiver and the high-frequency piezoelectric probe are integrated, and the receiver is used for synchronously collecting a first ultrasonic response signal modulated by micro damage in the welding seam; the feature extraction module is configured to demodulate a high-order harmonic component caused by material fatigue damage from the first ultrasonic response signal; the relative energy ratio of the high-order harmonic component to the fundamental component is calculated, and a nonlinear resonance spectrum distortion factor is generated; a first fatigue damage physical model is embedded in the service life evaluation module, and the service life evaluation module is configured to calculate and output the first residual fatigue service life of the to-be-detected aluminum alloy welding seam by taking the nonlinear resonance spectrum distortion factor as an input parameter.

The embodiment of the present disclosure provides a millimeter wave frequency doubling circuit with reconfigurable harmonic suppression function, comprising: a frequency doubling unit adopting a Push-Push structure, a reconfigurable LC trap unit, and an output matching network; wherein the input end of the reconfigurable LC trap unit and the input end of the output matching network are sequentially connected with the output end of the frequency doubling unit; the frequency doubling unit is used for receiving a differential signal and processing the differential signal to output a frequency doubled signal; the reconfigurable LC trap unit is used for suppressing specific high-order harmonics of the frequency doubled signal; and the output matching network is used for impedance matching and outputting the frequency doubled signal after harmonic suppression. In this way, through the collaborative design of the frequency doubling unit adopting the Push-Push structure, the reconfigurable LC trap unit and the output matching network, a millimeter wave frequency doubling circuit with miniaturization, high efficiency, high harmonic suppression precision and frequency reconfigurability is realized.

The invention relates to the technical field of general control or regulation systems, and discloses a self-adaptive regulation system for the machining process of a laser cutting rotary worktable, which comprises a regulator for synchronously acquiring C-axis angle and displacement data before machining, executing harmonic analysis to identify harmonic parameters of a workpiece, executing a quality control decision based on high-order harmonics, and adjusting the quality of the workpiece according to the quality control decision; generating a feed-forward compensation model by using the first-order and second-order harmonic parameters; according to the method, the control system obtains the capability of actively identifying the real geometric model of the workpiece before machining, the hysteresis of traditional feedback control is avoided based on feed-forward compensation of the real model, and the stability of the machining process is ensured.

The application provides a rapid detection device and method for evaluating aluminum alloy weld fatigue life, and relates to the technical field of fatigue detection. The device comprises: an ultrasonic excitation and collection module, which comprises a broadband power amplifier and a high-frequency piezoelectric probe, is used for contacting an aluminum alloy weld to be detected, and is configured to inject a group of high-energy and continuously swept-frequency ultrasonic excitation signals into the weld; a receiver, which is integrally integrated with the high-frequency piezoelectric probe, is used for synchronously collecting a first ultrasonic response signal modulated by internal micro-damage of the weld; a feature extraction module is configured to demodulate a high-order harmonic component caused by material fatigue damage from the first ultrasonic response signal; the relative energy ratio of the high-order harmonic component and a fundamental wave component is calculated, a nonlinear resonance spectrum distortion factor is generated; and a life evaluation module, which is embedded with a first fatigue damage physical model, is configured to take the nonlinear resonance spectrum distortion factor as an input parameter, calculate and output a first residual fatigue life of the aluminum alloy weld to be detected.

The invention relates to the technical field of chemical production, in particular to a construction method and device of a viscoelastic material model, electronic equipment and a storage medium. The construction method comprises the steps that through dynamic mechanical testing of a linear viscoelastic area, the change relation of the energy storage modulus and the loss modulus along with the angular frequency is obtained; determining the shear viscosity and the characteristic relaxation time of the material; acquiring a stress response signal under a large-amplitude oscillation shear condition, extracting a high-order harmonic coefficient representing a nonlinear behavior through harmonic analysis, preliminarily determining a nonlinear parameter of the constitutive model according to the high-order harmonic coefficient, and calculating a theoretical stress response; and finally, by taking the nonlinear parameter, the shear viscosity and the relaxation time as initial values and minimizing the deviation between a theory and actually measured stress response, iterative optimization is carried out until convergence, so that the viscoelastic material model is obtained. According to the method, the non-linear parameter identification precision and the calculation efficiency can be remarkably improved, and the constructed model has excellent prediction capability and reliability in a wide frequency and wide strain range.

The application relates to the field of motor control technology in the smart grid industry, and a control circuit of a flywheel energy storage system involves various power electronic components such as semiconductor field effect tubes, and serves high-precision control of a motor; the application discloses a space vector control method for a twelve-phase permanent magnet synchronous motor flywheel energy storage system, which comprises the following steps: S1, twelve-phase space vector decoupling fault-tolerant control, S2, high-order harmonic energy recovery closed loop, S3, quantum annealing parameter optimization layer, S4, flux linkage self-adaptive observer network, and S5, 18-dimensional switching vector table construction. Through multi-reference coordinate system transformation and redundant phase reconstruction algorithm, the scheme realizes quick fault-tolerant response of the twelve-phase motor under single-phase or two-phase fault, dynamically recombines a current path under fault, combines a negative sequence current compensation loop, effectively suppresses torque pulsation, and through sliding window FFT real-time detection of a harmonic distortion rate and adjustment of a controller bandwidth under high-speed charging and discharging conditions, the problem of insufficient dynamic response of a traditional fault-tolerant strategy is solved.

The invention relates to a predictive spare part method based on the abrasion degree of a numerical control machine tool, and belongs to the technical field of predictive spare parts. The method comprises the steps that the meshing frequency and the corresponding frequency characteristic value of the numerical control machine tool during normal work are determined; acquiring a time domain vibration signal of the ith day, and performing fast Fourier transform processing on the signal to obtain a frequency domain signal; determining a center coefficient score, and determining a center frequency index score; determining a central frequency criterion index score, and determining a central frequency serial number score; determining a center frequency score; respectively determining a fundamental frequency wear score, a low-order harmonic wear score and a high-order harmonic wear score; determining the wear degree score of the ith day, and determining the wear degree score of each machine tool to form wear degree time sequence data of the machine tool; and determining a residual life score according to the wear degree time sequence data of the machine tool, and predicting a spare part purchase plan according to the residual life score. The spare part purchase plan is guided by predicting the remaining life of the spare part.

The invention discloses an LED self-feedback photoelectric encoder chip system based on harmonic analysis and suppression. The system comprises an LED light source module (1), a photoelectric detection array module (2), a signal conditioning and analog-to-digital conversion module (3), an FFT harmonic analysis unit (4), a harmonic compensation control unit (5) and an LED driving current control module (6). The system performs fast Fourier transform analysis on sine and cosine signals output by the photoelectric detection array, extracts and identifies high-order harmonic components, generates compensation signals according to harmonic amplitude and phase, adjusts LED driving current in real time, and realizes stable light source output and signal harmonic suppression. Chip-level harmonic detection and dynamic compensation of the signal quality of the photoelectric encoder are realized, the linearity and the signal-to-noise ratio of incremental signals can be remarkably improved, the anti-interference performance and the resolution stability of a system are improved, and the method is suitable for the field of design and manufacturing of high-precision photoelectric encoder chips.

The application discloses a radio frequency front-end module, a power amplifier and electronic equipment. The radio frequency front-end module comprises a substrate provided with a first connecting node and a second connecting node, a power amplification chip, a first connecting piece, a second connecting piece and a matching module. The power amplification chip is provided with a first output port and a second output port. The first connecting piece is connected between the first output port and the first connecting node. The second connecting piece is connected between the second output port and the second connecting node. The matching module comprises a balun provided with a first input end and a second input end, a first wire and a second wire. The first wire is connected between the first connecting node and the first input end. The second wire is connected between the second connecting node and the second input end. By arranging the first wire and the second wire, the application can suppress high-order harmonics in a pair of radio frequency differential signals output by the power amplification chip, thereby improving the signal quality of radio frequency signals output by the subsequent balun.