20 results about "Bode plot" patented technology

This invention discloses a servo-elastic stabilization method based on multi-sensor information fusion, belonging to the field of flight control. Specifically, it involves: extracting and modeling the main load-bearing structure of the aircraft; calculating the modal frequencies, mode shapes, and mode shape slopes of the aircraft under unconstrained conditions; then combining the aircraft, a first sensor, servo motors, and the control system to form a closed-loop servo-elastic system; calculating the open-loop system transfer function from the control input to the feedback input of the control system, drawing an open-loop Bode plot, and determining the dangerous frequencies and corresponding dangerous natural modes; based on this, placing a second angular velocity sensor on the aircraft; then calculating and correcting the weighting coefficients of the two angular velocity sensor signals, and introducing the weighted signal into the control system instead of the original signal; comparing the system characteristics to ensure the servo-elastic stability of the aircraft without affecting the rigid body phase and amplitude.

The invention discloses a multi-port stability analysis method for a photovoltaic access traction power supply system, and belongs to the field of traction power supply systems. The method comprises the following steps: dividing the photovoltaic access traction power supply system into an active subsystem and a passive subsystem; respectively establishing an AC / DC hybrid admittance model of the active subsystem and an AC / DC hybrid impedance model of the passive subsystem; according to the AC / DC mixed admittance model of the active subsystem and the AC / DC mixed impedance model of the passive subsystem, an impedance return difference matrix is obtained based on the closed loop transfer function of the input voltage and the output current of the photovoltaic access traction power supply system; the impedance return difference matrix is converted into an upper triangular matrix according to a triangularization method, an impedance return difference matrix determinant is obtained, and a Bode diagram curve of the impedance return difference matrix determinant is obtained; and completing the stability analysis of the photovoltaic access traction power supply system according to the phase change of the Bode diagram curve. According to the method, the problem that the analysis of the influence of photovoltaic integration on the system stability is not comprehensive in the existing method is solved.

Disclosed herein is a method and system for analyzing wellbore fluid samples using impedance spectroscopy to identify chemical constituents and detect contaminants. The approach involves collecting fluid samples from a wellbore and performing chemical impedance spectroscopy by applying multiple discrete frequencies of alternating current, generating impedance spectra that are transformed into Nyquist and Bode plots for analysis. A data processing workflow handles raw impedance data through steps of labeling, cleaning incomplete sweeps, temperature thresholding, and temperature compensation to a reference standard. A hybrid modeling approach that integrates physics-based modeling (using a modified Randles circuit) with advanced data analytics techniques (utilizing Gaussian Process Regression) is utilized. Derived electrical properties, particularly susceptance and permittivity, are used to enhance the predictive capabilities of the model. This enables quantitative measurement of contaminants including mud filtrate and various salt types in wellbore fluids.

This invention discloses a method for designing an additional stabilizer to suppress low-frequency oscillations in a doubly-fed induction generator (DFIG) wind turbine. The method includes: constructing the input and output terminals of the additional stabilizer and designing the control loop; plotting the Bode plot of the closed-loop transfer function of the original system to determine the dominant oscillation frequency w. d and the phase lag value θ h Perform parameter tuning calculations for the phase compensation stage in the control loop; select the proportional coefficient K of the isolation stage of the additional stabilizer. e The quality coefficient ξ of the second-order bandstop filter with added stabilizer s and resonance coefficient K s Initialize the values; calculate the time δt required to suppress the disturbance and perform iterative calculations; and obtain the optimal parameter K. e ξ s and K s The values ​​are then substituted into the expressions for the isolation stage and the second-order band-stop filter. The additional stabilizer and design method for suppressing low-frequency oscillations in doubly-fed induction generator (DFIG) wind turbines provided by this invention can effectively suppress low-frequency oscillations in DFIG grid-connected systems and significantly enhance the system's stability under small disturbances.

The invention discloses a design method of a three-order active filtering automatic test system, and the method comprises the steps: controlling a PXI platform through LabVIEW programming to achieve the generation of a sweep frequency signal and the collection of filtering response, and completing the signal processing, characteristic analysis and result visualization. The system integrates six core technologies, namely a modularized hardware architecture, automatic process control, frequency domain parameter precision measurement, multi-order characteristic synchronous detection, software and hardware collaborative linkage and simulation data comparison. On the basis of retaining traditional functions such as setting waveform type, amplitude, sweep frequency range, sampling rate, trigger mode, recording cut-off frequency, gain and other parameters, exponential sweep frequency accurate excitation and adaptive signal acquisition are innovatively realized, link interference is reduced through matrix switch multi-channel scheduling, a LabVIEW parallel thread and a feedback node mechanism are combined, and the adaptive signal acquisition is realized. And closed-loop analysis of amplitude-frequency / phase-frequency characteristics and real-time drawing of a Bode diagram are completed.

The invention provides a stability judgment method for a direct-current bus of a full-power pumped storage unit, and relates to the technical field of hydroelectric power generation. The method comprises the steps that a direct-current bus capacitor is equivalent to two parallel equivalent capacitors, and the pumped storage unit is split into a unit side and a network side with a parallel connection point as a boundary; respectively constructing small signal models of the electrical devices of the two parts; based on each small signal model, respectively constructing a corresponding admittance model, and then constructing a corresponding impedance model; substituting the electrical parameters and the control parameters into the impedance model, and drawing a corresponding Bode diagram; and under the same working condition, if the phase difference at the amplitude intersection point of the two Bode diagrams is less than 90 degrees, the direct current bus does not generate interactive instability under the corresponding working condition, otherwise, the interactive instability occurs. According to the method, the modeling difficulty and model complexity of the full-power pumped storage unit can be effectively reduced, the characteristics of the pumped storage unit can be accurately reflected, and the interaction stability of a power system on a direct-current bus can be judged.

This invention discloses a modular simulation method for a direct-drive variable-speed pumped-storage unit, belonging to the field of hydropower storage technology. A piecewise linearized control block diagram for the direct-drive pumped-storage unit is established. The pump-turbine in the pumped-storage unit operates under two modes: power generation and motoring. Since the simulation analysis methods for power generation and motoring are largely similar, only the power generation mode is used as an example to establish the control block diagram. The value ranges of the PI regulation parameters for the power closed-loop and power multi-state modules are solved. After obtaining the value ranges, the Bode plot analysis method is used to design the power closed-loop regulation parameters. Simulation analysis under the power generation mode is performed based on the designed parameters to verify the effectiveness of the piecewise linear simulation method. The simulation method of this invention combines the simplicity of traditional fixed-parameter PID regulation with the adaptability of novel PID regulation to multiple operating modes in the new energy power grid, effectively suppressing fluctuations in the new energy power grid.

This invention relates to the field of fuel cell technology and discloses a fuel cell impedance attribution method based on a physically interpretable impedance model. The method includes: performing impedance decomposition on the physically interpretable impedance model to obtain multiple sub-impedances of the fuel cell, including ohmic resistance, anode impedance, cathode activation impedance, cathode mass transfer diffusion impedance, and cathode mass transfer convection impedance; obtaining the frequency corresponding to the minimum value of the imaginary part of each sub-impedance, the inverse of the minimum value of the imaginary part, and the difference between the low-frequency real part value and the high-frequency real part value, as characteristic frequencies, imaginary peak values, and equivalent resistances; plotting the Nyquist plot, Bode plot, resistance ratio of the sub-impedance's equivalent resistance to the total equivalent resistance, and frequency-peak plot reflecting the relationship between the characteristic frequency and the imaginary peak value for each sub-impedance, to determine the contribution of each sub-impedance to the physically interpretable impedance model, thus realizing impedance attribution analysis under the physically interpretable impedance model.

This invention discloses a calibration method, storage medium, and electronic device for a position servo control system. Specifically, it includes: determining the open-loop transfer function and open-loop gain of the position servo control system and drawing a first Bode plot accordingly; determining whether the gain margin and phase margin of the first Bode plot meet set requirements; if both the gain margin and phase margin of the first Bode plot meet set requirements, calibration is completed; otherwise, proceed to the next step; drawing the expected second Bode plot based on the set gain margin and phase margin requirements; determining a calibration function and its parameters based on the first and second Bode plots; and completing the calibration. In the solution provided by this invention, based on geometric processing, the difference between the first and second Bode plots is analyzed to determine the calibration scheme, reducing the amount of data processing and enabling calibration to be completed even without a computer.

The invention discloses an SVG high-frequency oscillation suppression method based on voltage signal direct coupling, and the method comprises the following steps: S1, building an SVG impedance model which is not added with a high-frequency oscillation suppression control strategy through a harmonic linearization method; s2, constructing a high-frequency oscillation suppression control strategy of a voltage signal direct coupling cascade second-order high-pass filter; s3, parameters of the constructed high-frequency oscillation suppression control strategy are set; s4, establishing an SVG impedance model added with the high-frequency oscillation suppression control strategy after parameter setting through a harmonic linearization method; s5, comparing the Bode diagram and the Nyquist diagram of the SVG impedance model to which the high-frequency oscillation suppression control strategy is not added and the SVG impedance model to which the high-frequency oscillation suppression control strategy is added, and obtaining a comparison result; the objective of the invention is to solve the technical problem that the existing active damping technology for suppressing the high-frequency oscillation of the static var generator is difficult to meet the requirements of rapidity and steady state of high-frequency oscillation suppression at the same time.

The invention discloses a cascade system bus voltage stability domain evaluation method under small current disturbance, and relates to the technical field of power supply and distribution systems. The method comprises the following steps: constructing an impedance ratio test circuit; introducing non-intrusive current signal interference into bus voltage of the cascade system by an impedance analyzer to excite a feedback loop of the cascade system to operate; the stability criterion of the Middlebrok is simplified, and an improved stability criterion is obtained; according to the corresponding amplitude-frequency Bode diagram data of each load operation point obtained by the impedance ratio test circuit, the amplitude data of the corresponding amplitude-frequency Bode diagram of each load operation point is integrated and fitted through Matlab, and a fitting curved surface based on a test result is obtained; and comparing the fitting curved surface with a judgment area determined based on a stability criterion, and determining a stable operation boundary of the cascade system in a wide load range. According to the invention, the problem of the bus voltage stability of the black box cascade converter system in a wide load range is solved, and a test method without invading a bus line is provided.

The invention discloses a system and a method for testing broadband damping characteristics of a network construction type energy storage converter, and relates to the technical field of power electronic equipment testing, the system comprises the following components: a physical layer, a data acquisition layer, a data processing layer and an application layer; according to the method, the sweep frequency disturbance signal is optimized through a dynamic amplitude adjustment strategy, the problems that traditional fixed amplitude disturbance is weak in signal in a high-impedance frequency band and prone to overload in a low-impedance frequency band are solved, tests show that after dynamic amplitude adjustment is adopted, the signal-to-noise ratio of data collected in each frequency band is averagely increased by 28%, the signal-to-noise ratio of the low-frequency band of 1-45 Hz is increased most remarkably, and meanwhile, the signal-to-noise ratio of the low-frequency band of 1-45 Hz is increased more remarkably. And the data acquisition layer adopts a method of combining timestamp calibration and phase compensation, the synchronization precision is improved to a phase domain less than or equal to 0.5 degree, and the phase deviation near a 50Hz rated frequency is controlled within 0.2 degree, so that an impedance calculation error caused by the phase deviation is effectively avoided, and the accuracy of the Bode diagram phase-frequency characteristic is ensured.

Physics-informed neural networks and methods for modeling and analyzing feedback loop responses in electronic devices, including switching-mode power converters. The physics-informed neural network integrates physical principles with machine learning techniques to predict high-order transfer function parameters, such as poles, zeros, and gain, based on transient signals. These parameters are used to generate predicted frequency responses, including observable data like gain and phase, and non-observable data like poles and zeros. The predicted frequency responses are further translated into graphical representations, such as Bode plots and pole-zero plots, providing insights into system stability and performance. By extracting features that represent dynamic behavior and stability factors, the physics-informed neural network ensures predictions are physically meaningful and interpretable. The technology can be useful for real-time analysis, stability assessment, and automated compensation tuning in areas such as power management devices, industrial automation controllers, precision signal processing systems, and robotics platforms.

The invention relates to a network frequency disturbance-based network construction performance quantitative evaluation method and device for a network construction type energy storage converter. The method comprises the following steps: applying low-frequency sine type frequency disturbance with preset disturbance frequency and amplitude to grid-connected voltage of a grid-forming type energy storage converter; based on the grid-connected active power response function of the energy storage converter under the frequency disturbance, generating a Bode diagram of the output power and the disturbance frequency of the network construction type energy storage converter; based on a Pode diagram, network construction performance quantitative evaluation of the energy storage converter is established, and an equivalent inertia constant, a damping coefficient and an active frequency modulation droop coefficient of the network construction type energy storage converter are fitted by using asymptote characteristics and resonance point characteristics in an amplitude-frequency characteristic curve and a phase-frequency characteristic curve. And quantitative evaluation of the equivalent inertia constant, the damping coefficient and the active frequency modulation droop coefficient is completed. According to the experimental method for evaluating the GFM-PCS dynamic response based on the network frequency disturbance (NFP) method, quantitative evaluation of the network construction performance of the network construction type energy storage converter can be achieved.

The invention discloses a bandwidth broadening design method for a passive PCB Rogowski coil, and belongs to the technical field of coil design, and the method comprises the steps: building a circuit model; structure parameters of the coil are calculated according to the Faraday electron induction law; establishing a transfer function of the circuit model, and determining to-be-designed electrical parameters; performing calculation simulation on the to-be-designed electrical parameters, and determining the influence degree of the to-be-designed electrical parameters on the coil bandwidth; setting value ranges or combinations of different to-be-designed electrical parameters, and simulating and analyzing amplitude-frequency characteristics and phase-frequency characteristics of the transfer function; determining an influence trend of each to-be-designed electrical parameter on the coil bandwidth by measuring a change rule of a Baud diagram of the circuit model; and determining an adjustable electrical parameter, determining a value of the adjustable electrical parameter, and adjusting the circuit model. According to the PCB Rogowski coil, the bandwidth of the PCB Rogowski coil is widened on the basis that the use advantage that a power source is not needed for power supply is reserved, and the PCB Rogowski coil capable of measuring rapidly-changing current signals is designed.

A new energy unit black box model control parameter identification method based on an improved PSO algorithm specifically comprises the steps that an impedance model of a new energy unit is constructed, and a transfer function of the new energy unit is deduced based on the impedance model; acquiring frequency domain response characteristics based on the transfer function; wherein the frequency domain response characteristics are obtained by calculating the Bode diagram of the transfer function; and fitting the frequency domain response characteristics based on an improved PSO algorithm to identify control parameters. The improved PSO algorithm comprises the following steps: allocating different dynamic weight values to frequency points of different frequency bands; grouping the parameters to be identified according to the parameter sensitivity and setting different learning rates for different groups; and constructing a composite fitness function containing an amplitude error, a phase error and a parameter grouping error for optimization. According to the method, a dynamic frequency weight distribution strategy is introduced, interference of high-band switching noise is suppressed, high-sensitivity parameters and low-sensitivity parameters are treated differently, effective decoupling of strong coupling parameters is achieved, and interference of secondary parameter updating on core parameters is avoided.

This application discloses a transient damping-embedded photovoltaic energy storage power station grid-connected stability enhancement control method and system. This method preprocesses input data to construct a complex transfer function model of the interaction between the photovoltaic energy storage system and the grid. Combined with Bode plots and Nyquist stability curves, it analyzes the influence trends of parameters such as transient damping, further optimizes and executes parameter control, and realizes the stability interaction analysis and enhancement of the grid-connected and grid-integrated hybrid control system. Compared with traditional high-dimensional and physically multi-input multi-output models, this method is more practical, versatile, and scalable. It is of great significance and high practical value for promoting the consumption of new energy sources and enhancing the safety and stability support capabilities of energy storage and new energy sources for new power systems. It can be widely applied in the fields of new energy and energy storage technologies.

This invention provides a voltage-based converter stability evaluation method, comprising the following steps: S1. Injecting single-phase voltage disturbances of different frequencies into the common coupling point of the converter; S2. Obtaining the line voltage V of the converter under the single-phase voltage disturbance. ab and V bc and the line voltage V on the grid side t,ab S3. Based on line voltage V ab and V bc Determine the positive sequence component V of the converter's response voltage. p Based on line voltage V t,ab and line voltage V bc Determine the positive sequence component V of the grid-side response voltage. t,p S4. Based on positive-order component V t,p With the positive-order component V p S5. Plot a Bode plot of the ratio Vtp / Vp; Find the point in the Bode plot where Vtp / Vp is 0, and determine the crossover frequency f. c The stability of the converter is determined based on the phase corresponding to the crossover frequency.

The present invention relates to a method for determining at least one characteristic parameter of a component of a DC transformer (10) for an on-board electrical network of a motor vehicle (14) using an electronic computing device (16), wherein a first transfer function of a high-voltage-low-voltage DC transformer (12) is determined based on the small-signal behavior of the high-voltage-low-voltage DC transformer (12), and a second transfer function of the DC transformer (10) is determined based on the first transfer function such that the DC transformer (10) has at least one characteristic substantially the same as that of the high-voltage-low-voltage DC transformer (12), and the at least one characteristic parameter of the component of the DC transformer (10) is determined based on the determined second transfer function; the characteristic parameter is determined such that the DC transformer (10) has a step response substantially the same as that of the high-voltage-low-voltage DC transformer (12); and / or the characteristic parameter is determined such that the DC transformer (10) has a Bode plot substantially the same as that of the high-voltage-low-voltage DC transformer (12). The invention also relates to an electronic computing device (16).

This invention belongs to the field of grid-connected inverter technology, specifically relating to a method for improving the stability of multi-infeed systems of grid-connected inverters based on high bandwidth. The method of this invention utilizes the proportional gain of the PI controller in the current loop of a single grid-connected inverter (GCI). k p and integral coefficient k i and the proportional gain of the PI controller in the voltage loop k vp and integral coefficient k vi Using the variable as a variable, Bode plots of the closed-loop transfer function of the current loop and the closed-loop transfer function of the voltage loop of a single GCI are drawn. The frequency corresponding to -3dB in the Bode plot is selected, and this frequency is required to meet the high bandwidth requirement. High bandwidth is used as the model parameter of the GCI multi-infeed system to obtain the first model. The stability of the GCI multi-infeed system is improved based on the first model, so that the method of the present invention can effectively improve the stability of the GCI multi-infeed system.