31 results about "Bode plot" patented technology

Complex filters may be used to achieve compensation of a plant, corresponding for example to a power regulator or point-of-load (POL) regulator. Digital filter coefficients may be mapped to analogous poles and zeros, or they may be mapped to values of the quality factor (Q) of the output, frequency, and gain. The plant may be observed and characterized using a network analyzer to generate the Bode plot (or Nyquist plot) for the plant. The digital filter coefficients may be mapped to features that may be identified on the Bode plot (or Nyquist plot) to easily correlate characteristics of the digital filter or digital compensator to the plant characteristics. The mapped features may be adjusted, for example by a user, either manually or by executing one or more optimization algorithms, to achieve the desired results relative to the Bode plot (or Nyquist plot). The mapped features may then be reverse mapped to the digital filter or digital compensator coefficients to fine tune and implement the digital filter or digital compensator.

The invention discloses a holographic dynamic balance method based on empirical modal breakdown flexible rotor, which is characterized by the following: resolving the data of rotor in the whole speed raising course through empirical modal breakdown advantage based on holographic spectrum information integral elementary and system theory; extracting the industrial frequency component; drawing the holographic baud graph; calculating the weight quality and orientation of different rotary speeds, especially near the weight information of critical rotary speed. The invention breaks through the limitation of traditional stable data and reduces the risk, which can reach the better balancing effect.

Defects in components in ICs which may cause circuit failures during operation of the IC are often difficult to detect during and immediately after fabrication of the IC by DC test methods. A method of testing components to detect such defects using AC Impedance Spectroscopy is disclosed. Data may be analyzed using Nyquist plots and Bode plots. Nyquist plots of typical defect types are disclosed. Components may include MOS transistor gate structures, contacts, vias and metal interconnect lines. Components tested may be contained in integrated circuits or in test circuits. Integrated circuits containing components tested by AC Impedance Spectroscopy may be partially fabricated or deprocessed after fabrication.

The invention discloses a method for extracting failure characters of a rotary machine based on a Kalman order-domain-holo-spectrum theory. The capacity of processing unstable signals through Kalman order-domain analysis and the capacity of comprehensively and reliably reflecting the state of a unit through holo-spectrum are utilized in a composite mode. Through combination of the Kalman order-domain analysis and the holo-spectrum analysis, two-dimensional holo-spectrum can be used for failure diagnosis in fluctuation of speed, and force and couple decomposition, and holographic waterfall curve analysis of parking signals can be conveniently carried out. By means of the method, the application range of traditional holo-spectrum is greatly widened, various characteristic parameters of the parking signals are extracted, the defect that in the prior art, only bode plot analysis is overcome, the level and range for monitoring and diagnosing failures of the rotary machine are expanded, and powerful supporting is provided for healthy and reliable operation of the rotary machine.

The invention discloses a rotary machine fault feature extraction method based on a fractional order holographic principle. the rotary machine fault feature extraction method comprehensively utilizes the ability of fractional order Fourier transform for processing non-stationary signals and the ability of holospectrum for accurately reflecting the status of a machine set, and is applied to information extraction and fault diagnosis in the stopping process of a rotary machine. According to the method, the fractional order Fourier transform and the holospectrum are fused from data layers, a two-dimensional holospectrum and a three-dimensional holospectrum are reconstructed, and a holographic waterfall figure is applied to processing non-stationary information of cycling start and stopping; therefore, various feature parameters can be extracted for start and stopping signals, the application scope of the traditional holospectrum is greatly expanded, the traditional limitation of only carrying out Bode diagram analysis is broken through, the level and range of monitor and diagnosis of rotary machine faults are widened, and powerful support is provided for healthy and reliable operation of rotary machines.

A magnetic hard disk drive includes a method for eliminating that portion of track following error by a read / write transducer that is caused by repeatable runout of the disk tracks. The repeatable runout is eliminated by application of an iterative algorithm that calculates feed-forward correction terms based on gain coefficients iteratively calculated from the amplitude and phase portions of a Bode plot characterizing the system. The corrective coefficients can be inserted into the hard disk drive at a summing junction that redefines the centerline of the track, or at a summing junction that causes the actuator to follow the repeatable runout and make non-repeatable runout corrections relative thereto.

The invention discloses a method for quickly computing a Bode plot and a Nyquist plot of rotary mechanical vehicle starting and parking processes. The method is based on rotor vibration signals and key-phase signals, which are measured by an eddy current sensor, of the rotary mechanical vehicle starting and parking processes, and the Bode plot and the Nyquist plot of the vehicle starting and parking processes are quickly computed; and an integral computing process is based on Hilbert transform processing for the vibration signals of the vehicle starting and parking processes, and is combined with phase-retaining filtering processing for the vibration signals and extraction of periodic information in the key-phase signals, so that the Bode plot and the Nyquist plot of the rotary mechanical vehicle starting and parking vibration signals are quickly computed. Experimental data analysis results show that Bode plot and Nyquist plot curves computed by the method are smooth, vibration peak values and vibration phases which are obtained by the method are more accurate, phase computational precision is unaffected by rotation speed, and the method is a good method for computing Bode plots and Nyquist plots of rotary mechanical vehicle starting and parking unsteady signals.

A magnetic hard disk drive includes a method for eliminating that portion of track following error by a read / write transducer that is caused by repeatable runout of the disk tracks. The repeatable runout is eliminated by application of an iterative algorithm that calculates feed-forward correction terms based on gain coefficients iteratively calculated from the amplitude and phase portions of a Bode plot characterizing the system. The corrective coefficients can be inserted into the hard disk drive at a summing junction that redefines the centerline of the track, or at a summing junction that causes the actuator to follow the repeatable runout and make non-repeatable runout corrections relative thereto.

The invention belongs to the field of automatic control technology and particularly relates to a large-envelope flight interference estimation method and device. The large-envelope flight interferenceestimation method and device aim to solve the problem that in the prior art, an analysis method for a rigid aircraft cannot be applied to analysis of flight dynamic characteristics of an elastic aircraft. The large-envelope flight interference estimation method comprises the steps that an input signal and an output signal of a large-envelope aircraft are acquired respectively, fast Fourier transformation signal analysis is performed on the input signal and the output signal, division operation is performed on the signals obtained through analysis, and a Bode plot of the output signal to the input signal is obtained; a sub-region image in the Bode plot is extracted; and the sub-region image of the Bode plot is input into a convolutional neural network model for recognition, and the category of the sub-region image of the Bode plot is obtained to complete large-envelope flight interference estimation. Through the method, a vibration mode offline learning mechanism of a deep learning mechanism and an online robust flexible identification mechanism can be formed, and online measurement and calculation of elastic feature parameters are realized.

A simultaneous rapid open and closed loop bode measurement plot is described in which testing of the servo controlled instrument occurs under closed loop conditions using a binary pseudo-random sequence. The binary pseudo-random sequence is injected into the servo while the system under test is operating closed loop in order to generate bode plots for open loop and closed loop conditions. The present invention provides measurement results approximately 1,000 times faster than a swept sinusoid approach and provides superior dynamic range as compared to random white noise test input sources.

An automatic gain adjustment support device according to this invention supports automatic adjustment of a control gain in a control loop for a servomotor controller which controls a servomotor. The automatic gain adjustment support device includes a frequency characteristic measuring unit, a display unit, a condition setting unit, an automatic gain adjusting unit, and a parameter setting unit. The frequency characteristic measuring unit measures frequency characteristics of the control loop in the servomotor controller. The display unit displays, in Bode diagram form, the frequency characteristics of the control loop. The condition setting unit sets a target gain value at a predetermined frequency. The automatic gain adjusting unit automatically adjusts the control gain in the control loop to the target gain value at the predetermined frequency set by the condition setting unit. The parameter setting unit sets the control gain to the servomotor controller.

The invention discloses a method for drawing a Bode plot, and an oscilloscope. The method comprises the following steps that: obtaining a signal source configuration parameter and a Bode plot displaycoordinate parameter set on the oscilloscope; according to the signal source configuration parameter, calculating signal source frequency; configuring the signal source configuration parameter and thesignal source frequency to a signal source to enable the signal source to generate a detection signal used for detecting a detected amplification circuit; according to the output signal of the detected amplification circuit, calculating the time base and the voltage range of the oscilloscope; according to the obtained amplitude and offset phase of the output signal of the detected amplification circuit as well as a Bode plot display coordinate parameter, calculating an amplitude-frequency point coordinate and a phase frequency point coordinate; and independently according to the amplitude-frequency point coordinate and the phase frequency point coordinate, drawing the Bode plot. Since the oscilloscope can automatically control the signal source and automatically draw the Bode plot according to a small quantity of parameters set by the user, the Bode plot drawing function of the Bode plot is realized, so that tedious work for manually drawing the Bode plot is effectively avoided, and efficiency is improved.

The invention discloses a method for extracting fault features of rotating machinery based on the principle of fractional-order holography, which comprehensively utilizes the ability of fractional-order Fourier transform to process non-stationary signals and the ability of holographic spectrum to accurately reflect the state of the unit, and is applied to the information of the start-stop process of rotating machinery extraction and troubleshooting. This method fuses the fractional Fourier transform and the holographic spectrum from the data layer, reconstructs the two-dimensional and three-dimensional holographic spectrum and the holographic waterfall image and applies them to the processing of the unsteady state information of the rotor starting and stopping, and realizes the multiple start and stop signals. The extraction of a variety of characteristic parameters expands the scope of application of traditional holographic spectra, breaks through the limitations of Bode diagram analysis in traditional situations, expands the level and scope of fault monitoring and diagnosis of rotating machinery, and provides a powerful tool for the healthy and reliable operation of rotating machinery. support.

The invention discloses a rotating machinery fault feature extraction method based on the principle of Kalman order-holographic spectrum, which comprehensively utilizes the ability of Kalman order to analyze and process non-stationary signals and the ability of holographic spectrum to comprehensively and reliably reflect the state of the unit. Combining the Kalman order ratio analysis and the holographic spectrum analysis can not only use the two-dimensional holographic spectrum to carry out fault diagnosis when the rotational speed fluctuates, but also can conveniently perform force and force couple decomposition and holographic waterfall diagram analysis on the start-stop signal. It expands the application scope of the traditional holographic spectrum, realizes the extraction of various characteristic parameters for the start-stop signal, breaks through the limitation of only Bode diagram analysis in the traditional situation, and expands the level and scope of fault monitoring and diagnosis of rotating machinery. It provides strong support for the healthy and reliable operation of machinery.

The invention relates to a method for making a Bode plot for starting-stopping process analysis. The method comprises three steps: (1) reading a pair of vibration displacement arrays, i.e. an x signal array and a y signal array which are collected at each rotation speed in the starting or stopping process; (2) synthesizing and making the corresponding rotation frequency vibration ellipse of the x signal array and the y signal array at each rotation speed and extracting various parameters of the rotation frequency vibration ellipses; and (3) arranging the evaluated rotation frequency vibration ellipse (can accompany with some parameters) at each rotation speed, or the maximum vibration value (amplitude) parameter of the rotation frequency vibration ellipse, or the maximum vibration direction parameter of the rotation frequency vibration ellipse or some other parameters of the rotation frequency vibration ellipse according to the rising speed or reducing speed sequence to form a plot. The Bode plot made by the method can better reflect the change characteristics of the rotation shaft vibration in the starting-stopping process of a machine and equipment.

The invention intends to provide a technique that achieves a sufficient phase margin with ease. The circuit includes a power supply circuit that is formed with a phase compensating resistor and a phase compensating capacitor, between a second input terminal of a differential amplifier and a low supply voltage. Thereby, the first pole frequency in the overall gain is determined by the first pole frequency in the voltage-dividing resistor stage in the Bode diagram for the pole / zero compensation, which is shifted to a lower frequency. Also, the zero point cancels the first pole frequency in the differential amplifier stage, which reduces the phase delay to secure the phase margin. And, since the phase compensating resistor can take a considerably high resistance, the same characteristic can be achieved with a low capacitance of the phase compensating capacitor; thereby, the phase compensation becomes possible with a resistor and a capacitor having a smaller size than the pole / zero compensation with the internal supply voltage.

The invention provides a detection method of bending of a rotor of a steam turbine. The method includes following steps: S10, monitoring the steam turbine, and obtaining monitoring data in processes of starting and shutdown of a set; S20, generating a Bode plot of shafting vibration with the change of the rotating speed in the processes of starting and shutdown of the set according to the monitoring data; S30, determining the rotor is bent if a second detection threshold is exceeded, and moving to step S40 if not, wherein the preset second detection threshold is used for comparing vibration values changed with the rotating speed in the shafting starting process; and S40, determining the rotor is bent if a third detection threshold is exceeded, wherein the preset third detection threshold is used for comparing the Bode plot changed with the rotating speed at this shafting start and shutdown. According to the method, an online vibration monitoring and analysis system of the steam turbine is applied, vibration spectrum analysis, a set vibration pass value, a turning current, and the rotor shaking degree are combined, and the function of accurate determination of the bending of the rotor can be realized.

Defects in components in ICs which may cause circuit failures during operation of the IC are often difficult to detect during and immediately after fabrication of the IC by DC test methods. A method of testing components to detect such defects using AC Impedance Spectroscopy is disclosed. Data may be analyzed using Nyquist plots and Bode plots. Nyquist plots of typical defect types are disclosed. Components may include MOS transistor gate structures, contacts, vias and metal interconnect lines. Components tested may be contained in integrated circuits or in test circuits. Integrated circuits containing components tested by AC Impedance Spectroscopy may be partially fabricated or deprocessed after fabrication.

The invention discloses a holographic dynamic balance method based on empirical modal breakdown flexible rotor, which is characterized by the following: resolving the data of rotor in the whole speed raising course through empirical modal breakdown advantage based on holographic spectrum information integral elementary and system theory; extracting the industrial frequency component; drawing the holographic baud graph; calculating the weight quality and orientation of different rotary speeds, especially near the weight information of critical rotary speed. The invention breaks through the limitation of traditional stable data and reduces the risk, which can reach the better balancing effect.

A method and digital oscilloscope supporting variable-amplitude scanning of Bode plots, comprising: acquiring a variable-amplitude configuration file set by a user on the digital oscilloscope; controlling a signal source to sequentially generate each group of Configure a section of excitation signal corresponding to the information to input an excitation signal whose amplitude varies with frequency to a circuit to be detected; obtain an output signal generated by the circuit to be detected in response to the excitation signal, and calculate the amplitude according to the output signal, excitation signal and configuration information The measurement results of the frequency response and / or the measurement results of the phase-frequency response; draw a Bode plot based on the measurement results of the magnitude-frequency response and / or the measurement results of the phase-frequency response. This application not only provides the setting method of the variable amplitude configuration file, but also provides the method of generating the scanning amplitude of different frequency points, and uses the variable amplitude scanning form to measure the circuit to be detected, which can meet the needs of technicians for the measurement of special circuits and the Bode Analysis of graph properties.

The invention provides an impedance measurement method for disturbance self-adaptive adjustment, which belongs to the field of power quality and control. The impedance measurement device involved in the method includes a disturbance injection unit and a disturbance control unit. The impedance measurement method selects the disturbance frequency by linear interpolation in the Bode diagram coordinate system, predicts the impedance to be measured, and adjusts the injection according to the amplitude and phase of the predicted impedance. The magnitude of the disturbance, the linearity of the impedance is judged according to the actual measured impedance, and the next frequency direction and step size are adjusted. The method is simple to implement, and can realize more intensive measurement of grid-connected equipment whose impedance characteristics are completely unknown in a frequency band with irregular impedance, and prevents the frequency step from being too large and losing information. Adjusting the size of the injected disturbance current according to the predicted impedance can effectively prevent the damage to the equipment caused by the excessive injection of the disturbed current; the provided impedance measurement method can realize the adaptive control of the disturbance frequency step and amplitude.

The invention discloses a rotary machine fault characteristic extraction method based on order-holospectrum principle, wherein the ability of order analysis for processing non-stationary signal and the ability of holospectrum for comprehensively and reliably reflecting machine set status are utilized. The ability of order analysis and the ability of holospectrum are fused, so that fault diagnosis an be carried out by utilizing two-dimensional holospectrum when speed oscillation, and force and force couple decomposition and holographic waterfall chart analysis can be carried out conveniently on cycling start and stopping signals. According to the method, the application scope of the traditional holospectrum is greatly expanded, various characteristic parameters can be extracted for the cycling start and stopping signals, the traditional limitation of only carrying out Bode diagram analysis is broken through, the monitor and diagnosis level and range of rotary machine faults are widened, and powerful support is provided for rotary machines healthily and reliably.

The invention discloses a method and system for active damping control of an LCL inverter in a weak power grid, and relates to the technical field of grid-connected inverters. The key points of the technical solution are: the voltage signal is used as the input of a high-pass filter compensation strategy to obtain active damping Parameters; the active damping parameters and phase margin compensation coefficient sequence are used as the input of active damping control, and the system open-loop Bode diagram is obtained by simulation; the open-loop cut-off frequency and the open-loop cut-off frequency and the The distribution of the phase margin, and select the optimal phase margin compensation coefficient; after the optimal phase margin compensation coefficient is fused with the active damping parameters, the leading phase compensation signal is obtained; the leading phase compensation signal is combined with the multi-resonance control The active damping control of the LCL inverter is realized after the output signal of the inverter is superimposed. The invention improves the phase margin when the system is connected to the grid, reduces the use of high-precision sensors, and has good robustness and dynamic response capability.

The invention discloses a digital oscilloscope and a method for measuring a bode diagram, and a readable storage medium. The digital oscilloscope comprises a first front end module, at least one second front end module, a signal source and a processor; the first front end module and the second front end collect an input signal and an output signal of a tested part, and preprocess the respectivelycollected signal; the processor performs effective signal searching on the preprocessed signals to obtain the respective actual signal frequency; the measurement error caused by the element precisionproblem is improved; the collected signal is filtered according to a searching result so as to filter the interference of the noise, the signal to noise ratio of the signal is improved, the phase discrimination processing and the effective value detection wave processing are performed on the filtered signal so as to obtain phase difference of the input signal and the output signal and the corresponding detection wave data; and finally, the bode diagram is drawn according to the phase difference and the detection wave data. The measurement data is hard to be interfered by various noises, the signal-to-noise ratio of the measurement result is improved, and the precision of the drawn bode diagram is higher.

The invention belongs to the technical field of automatic control, and in particular relates to a method and device for large-envelope flight interference estimation. The invention aims to solve the problem that the analysis method of the rigid aircraft in the prior art cannot be applied to the flight dynamics characteristics of the elastic aircraft. The present invention provides a large-envelope flight interference estimation method, which includes obtaining input signals and output signals of a large-envelope aircraft respectively, performing fast Fourier transform signal analysis on the input signals and output signals, and dividing the analyzed signals Operation to obtain the Bode diagram of the output signal versus the input signal; extract the sub-region image in the Bode diagram; input the sub-region image of the Bode diagram into the convolutional neural network model for identification, and obtain the category of the sub-region image of the Bode diagram In order to complete the large envelope flight interference estimation. The method of the present invention can form a vibration mode offline learning mechanism of a deep learning mechanism and an online robust flexible identification mechanism, and realize online measurement and calculation of elastic characteristic parameters.

A power supply design method based on frequency domain analysis, which includes the following steps: the first step is to evaluate the test platform, measure the open-loop transfer function of the test platform, and determine the design target; the second step is to load the test target, according to Test the parameters to obtain the compensation parameters, and draw the Bode diagram of the compensation parameters; then superimpose the Bode diagram of the compensation parameters and the Bode diagram of the open-loop transfer function to obtain a closed-loop curve; the third step is to adjust the parameters of the error amplifier, select parameter value, and the selected parameter value is debugged in the circuit board of the specific application, and the Bode diagram response curve of the whole loop is obtained; the fourth step is to confirm the test result, and obtain the closed-loop result on the test platform. Bode diagram, comparing the closed-loop Bode diagram on the test platform with the computer simulation diagram to confirm whether the two match. The invention greatly reduces the design period, improves the quality of products, and improves the research and development efficiency.

A method for reducing the order of the LCL-T module of a photovoltaic power generation system. Under the condition that the isolation transformer is not saturated, a mathematical model based on the LCL-T module of the photovoltaic power generation system is established, and the filter input voltage and the filter output current and the transformer primary voltage are obtained respectively. The transfer function between the side currents, the weighted feedback current is introduced to achieve zero and pole cancellation, and the purpose of simplification is achieved; in the case of isolation transformer saturation, considering the primary and secondary side resistances and excitation resistance of the isolation transformer, the input voltage of the filter is obtained. The transfer function to the output current of the primary side of the transformer adopts the Rolls approximation method of the high-order system of the Rolles stability law, and reduces the high-order LCL-T module to a first-order system of equivalent resistance and equivalent inductance in series; PSCAD / EMTDC modeling simulation and MATLAB data processing, Bode plot verification, and comparing the detailed model with the equivalent model results can effectively shorten the simulation time and improve the simulation accuracy.

The invention provides a detection method of bending of a rotor of a steam turbine. The method includes following steps: S10, monitoring the steam turbine, and obtaining monitoring data in processes of starting and shutdown of a set; S20, generating a Bode plot of shafting vibration with the change of the rotating speed in the processes of starting and shutdown of the set according to the monitoring data; S30, determining the rotor is bent if a second detection threshold is exceeded, and moving to step S40 if not, wherein the preset second detection threshold is used for comparing vibration values changed with the rotating speed in the shafting starting process; and S40, determining the rotor is bent if a third detection threshold is exceeded, wherein the preset third detection threshold is used for comparing the Bode plot changed with the rotating speed at this shafting start and shutdown. According to the method, an online vibration monitoring and analysis system of the steam turbine is applied, vibration spectrum analysis, a set vibration pass value, a turning current, and the rotor shaking degree are combined, and the function of accurate determination of the bending of the rotor can be realized.

The invention discloses a method for quickly computing a Bode plot and a Nyquist plot of rotary mechanical vehicle starting and parking processes. The method is based on rotor vibration signals and key-phase signals, which are measured by an eddy current sensor, of the rotary mechanical vehicle starting and parking processes, and the Bode plot and the Nyquist plot of the vehicle starting and parking processes are quickly computed; and an integral computing process is based on Hilbert transform processing for the vibration signals of the vehicle starting and parking processes, and is combined with phase-retaining filtering processing for the vibration signals and extraction of periodic information in the key-phase signals, so that the Bode plot and the Nyquist plot of the rotary mechanical vehicle starting and parking vibration signals are quickly computed. Experimental data analysis results show that Bode plot and Nyquist plot curves computed by the method are smooth, vibration peak values and vibration phases which are obtained by the method are more accurate, phase computational precision is unaffected by rotation speed, and the method is a good method for computing Bode plots and Nyquist plots of rotary mechanical vehicle starting and parking unsteady signals.

The invention discloses an active damping control method and system for an LCL inverter of a weak power grid, and relates to the technical field of grid-connected inverters. The main points of the invention are that the method comprises the steps: taking a voltage signal as the input of a high-pass filtering compensation strategy, and obtaining an active damping parameter; taking the active damping parameters and the phase margin compensation coefficient sequence as input of active damping control, and obtaining a system open-loop Bode diagram through simulation; extracting the open-loop cut-off frequency in the system open-loop Bode diagram and the distribution condition of the open-loop cut-off frequency and the phase margin, and selecting an optimal phase margin compensation coefficient; after the optimal phase margin compensation coefficient and the active damping parameter are fused, obtaining a leading phase compensation signal; and overlapping the leading phase compensation signal with an output signal of the multi-resonant controller to realize active damping control of the LCL inverter. According to the method, the phase margin during grid connection of the system is improved, the use of a high-precision sensor is reduced, and the method has good robustness and dynamic response capability.