260 results about "DC bias" patented technology

The invention is suitable for the technical field of resonant converters, and provides a starting control circuit and a resonant converter. The starting control circuit comprises a feedback module, a comparison selection module and a logical operation module, the comparison selection module is electrically connected with the feedback module and the logical operation module, the feedback module is used for being electrically connected with the output end of a resonant conversion circuit in the resonant converter, and the logical operation module is used for being electrically connected with a driving circuit in the resonant converter. According to the starting control circuit provided by the embodiment of the invention, the resonant capacitor voltage constraint threshold value which is gradually enlarged along with the starting process can be constructed, smooth establishment of resonant capacitor direct current bias is realized, the fluctuation amplitude of the resonant capacitor voltage is limited, the problem that the total bus voltage is applied to the resonant inductor in a traditional scheme is avoided, and the starting control circuit is suitable for a high-voltage power supply. Finally, the resonance current peak value in the starting stage is effectively suppressed, and the impact of current stress on core devices such as a switching tube and a resonance inductor is reduced.

The invention provides an excitation amplitude automatic closed-loop control system and method for a DLCP test. The system comprises a multi-frequency alternating current excitation and direct current bias voltage applying module which is used for automatically applying alternating current excitation signals and direct current bias voltage signals according to a preset excitation amplitude sequence under a plurality of test frequencies; the PID closed-loop control module is used for performing closed-loop correction on the applied voltage according to the response of the test port of the tested semiconductor device, so that the condition of the applied voltage at the test port meets a preset requirement; the capacitance measurement module is used for acquiring an equivalent capacitance response signal of the tested semiconductor device; the capacitance test data caching module is used for performing associated marking and classified caching on the capacitance test data according to the test frequency, the excitation level and the bias voltage set point; and the main control module is used for coordinating automatic test processes under the conditions of a plurality of test frequencies and different excitation amplitudes and outputting corresponding capacitance test data so as to improve the consistency, stability and automation degree of the DLCP test.

The invention relates to the technical field of radio frequency integrated circuits, and discloses a low-noise voltage-controlled oscillator circuit which comprises a source electrode following low-noise bias circuit with digital calibration, a source electrode following low-noise bias circuit with digital calibration, a source electrode following low-noise bias circuit with digital calibration and a source electrode following low-noise bias circuit with digital calibration, the cross-coupled amplifier array is composed of a plurality of units, and the source electrode of the cross-coupled amplifier array suppresses low-frequency noise through a resistance-capacitance feedback network and receives a digital amplitude calibration signal so as to dynamically adjust the number of working units and stabilize the output amplitude; the amplitude self-calibration loop consists of digital logic and a peak detector; the switched capacitor unit array is provided with stable direct-current bias; and a wide linear variable capacitor array driven by the stepped bias voltage. Through deep fusion of digital and analog technologies, the phase noise is remarkably reduced, the linear tuning range is widened, the amplitude stability is ensured, the power consumption is reduced, and the method is particularly suitable for a high-performance radio frequency communication chip of the Internet of Things.

A non-interferometric thin film lithium niobate electro-optical modulator for data transmission including a laser, configured to generate an input continuous wave light beam; a non-interferometric thin film lithium niobate modulator including an optical waveguide situated along with the coplanar transmission lines and the DC bias conductors. The propagation constant of the optical waveguide is tuned and modulated by the RF data signal and the DC bias voltage traveling on the coplanar transmission lines and the DC bias conductors. The modulator can be tuned at quadrature point by the DC bias voltage. The optical power can be modulated by the RF data signal travelling on the coplanar transmission line; a low noise RF amplifier for data signal amplification; and a bias tee for combining the data signal and DC bias voltage and send them to the coplanar transmission lines.

The invention discloses a direct current magnetic bias tolerance evaluation method, device and equipment of a transformer and a storage medium, and relates to the technical field of power systems, and the method comprises the steps: processing an initial finite element model of a to-be-evaluated transformer to obtain a target finite element model; the method comprises the following steps: performing an experiment on a to-be-evaluated transformer to obtain a reference data set, converting model parameters into standard nominal values to determine a probability distribution result, sampling the to-be-evaluated transformer to obtain a sampling result, and extracting sample points in the result to obtain a parameter extraction result to generate target simulation data; correcting the simulation data based on the reference data set to obtain a correction result, establishing a transformer direct current prediction model, and predicting a working condition vector of the to-be-evaluated transformer to obtain a prediction output result; the prediction output result is inverted based on the actual data of the to-be-evaluated transformer to obtain the direct current magnetic bias current, the direct current magnetic bias tolerance evaluation result is obtained through evaluation, and the accuracy and rationality of transformer direct current magnetic bias tolerance evaluation are improved.

The invention provides an external direct current bias device for a network analyzer and a test method thereof, and relates to the technical field of direct current bias, the external direct current bias device for the network analyzer comprises a test device, a tested device and an external direct current bias circuit; the external direct current bias circuit is arranged between the test equipment and the tested device; direct current bias supply and high-frequency test signal transmission control are carried out on the test equipment and the tested device through the external direct current bias circuit, the performance of the test equipment can be remarkably improved through the external direct current bias circuit, and the test intelligence and precision level of devices such as a signal inductor and the like is enhanced.

The invention discloses a W-band switching line MMIC phase shifter based on an aligned CNT Schottky diode. The phase shifter comprises a substrate, a radio frequency input port, a radio frequency output port, two transmission paths with different physical lengths, a switch selection network and a direct current bias circuit. Wherein the switch selection network adopts an aligned carbon nanotube Schottky diode and is configured at the input end and the output end of the transmission path. Complementary control voltage is applied through the direct-current bias circuit, the switch selection network is driven to enable the selected paths to be conducted at the two ends at the same time and the unselected paths to be cut off at the two ends at the same time, and therefore discrete switching of phases is achieved. The high-frequency characteristic of the aligned carbon nanotube device is combined with the double-end complementary selection topology, so that the problem that the amplitude imbalance and the phase precision are difficult to consider at the W wave band is effectively solved, the signal leakage and the parasitic resonance of a non-conducted branch are remarkably inhibited, and the low-insertion-loss high-isolation low-insertion-loss high-isolation low-insertion-loss high-isolation low-insertion-loss high-isolation low-insertion-loss high-isolation low-insertion-loss high-isolation low-insertion-loss high-isolation low-insertion-loss low

Reciprocal quantum logic (RQL) bias-level sensors are fabricated on an RQL integrated circuit (IC) to sample AC or DC bias values provided to operational RQL circuitry on the RQL IC. The bias-level sensors, or samplers, include Josephson transmission lines (JTLs) or logic gates having strengthened or weakened bias taps as compared to bias taps of JTLs or logic gates in the operational RQL circuitry. Sampler JTLs or logic gates with weakened bias taps to AC clock resonators can have lower limits of their operational ranges placed near an optimal bias point at the centroid of the operating region of the operational RQL circuitry. Staging relative strengths of the bias taps of the samplers in an ensemble of samplers allows for outputs of wrapper circuitry to be indicative of whether a provided bias value is an improvement or optimization of the bias value when varied over a range.

This invention relates to the field of power transformer protection technology, and discloses a transformer DC bias suppression system and method. The method includes collecting subway operation, power grid structure, and soil geological parameters; establishing a dynamic calculation model based on these parameters to generate distribution data of rail potential, stray current, and ground potential; constructing a bias assessment model to calculate the dynamic DC current flowing through the transformer neutral point and the excitation current distortion; using a random forest algorithm for evaluation, outputting a quantitative impact level and a set of key factors; and based on this level, key factors, and transformer grounding method, formulating a suppression strategy that includes configuration parameters of a silicon carbide PiN diode active suppression device and a grounding optimization scheme. This invention achieves accurate assessment and targeted suppression of DC bias problems caused by subways.

The invention discloses a CLCC converter transformer iron core state characteristic analysis method, system, medium and equipment, and the method comprises the steps: collecting a neutral point current signal of a converter transformer in real time in the operation process of a CLCC converter valve; performing wavelet multi-resolution analysis on the neutral point current signal, decomposing the neutral point current signal into an approximation coefficient and a detail coefficient, and reconstructing a high-frequency detail component to extract a transient direct current bias component; calculating a bias amplitude, a bias duration and a bias direction based on the transient DC bias component; evaluating the residual magnetism state and saturation tendency of the iron core according to the bias amplitude, the bias duration and the bias direction, judging that the iron core has positive saturation tendency when the bias direction is positive, and judging that the iron core has negative saturation tendency when the bias direction is negative; quantizing the residual magnetism level of the iron core based on the bias amplitude and the bias duration; and in combination with the operation parameters of the converter transformer, generating an iron core state evaluation report and outputting loss increase, anti-short-circuit capability decrease or insulation deterioration risk early warning.

The application discloses a transmitting local oscillator leakage correction method for a zero intermediate frequency system, which comprises the following steps: obtaining a first direct current bias signal of a zero intermediate frequency receiver according to a first positive signal and a first negative signal sent by a zero intermediate frequency transmitter; obtaining an amplitude attenuation parameter alpha and a phase deviation parameter of a second positive signal between the zero intermediate frequency receiver and the zero intermediate frequency transmitter according to the first direct current bias signal and the second positive signal, wherein the second positive signal is obtained by applying a strong direct current signal to an I path of the zero intermediate frequency transmitter; obtaining a second direct current bias signal based on the amplitude attenuation parameter alpha and the phase deviation parameter; superimposing a third direct current bias signal opposite to the second direct current bias signal on the zero intermediate frequency transmitter to complete the correction of the transmitting local oscillator leakage. Compared with the prior art, the application uses a relatively simple algorithm to solve the transmitting local oscillator leakage problem in the zero intermediate frequency transceiver, saves time and hardware resources, and can be used for the initialization correction and tracking correction of the transmitting local oscillator leakage.

The application discloses a linear polarization in-band scattering reconfigurable radiation time-sharing control array antenna and belongs to the technical field of antenna engineering, which comprises an antenna unit and a one-to-sixteen power divider, wherein the antenna unit is connected with the one-to-sixteen power divider; the antenna unit comprises a radiation patch one, a dielectric substrate one, a radiation patch two, a dielectric substrate two, a feed coupling branch, a feed metal column, a dielectric substrate three, a metal floor with holes and a dielectric substrate four; the bottom of the dielectric substrate four is provided with a PIN tube one, a PIN tube two, a feed transmission line, a DC biasing device, a reflective phase shifter and a low-pass filter; the DC biasing device is connected with the reflective phase shifter and the feed transmission line through the low-pass filter; and the feed metal column passes through the dielectric substrate three, the metal floor with holes, the dielectric substrate four in sequence and is connected with the feed transmission line. The application can not only guarantee the normal radiation efficiency of the antenna, but also effectively improve the reconfigurability of the antenna scattering.

The application relates to the technical field of intelligent sensor calibration and characteristic parameter quantification, and discloses a sensitivity coefficient quantitative calibration method of an intelligent sensor. Original output voltages are collected in sequence at different inclination positions and direct current bias is removed, a multilayer exponential smoothing kernel is adaptively constructed based on the maximum span and the minimum adjacent difference of the voltage sequence, and the signal is subjected to multiscale smoothing; the gradient of each layer of the smoothed voltage sequence is extracted by adopting central difference and end point difference respectively, and the maximum gradient and the corresponding inclination value are extracted in each layer as the local sensitivity; the sensitivities of the layers are arithmetically averaged to obtain the comprehensive sensitivity coefficient; finally, the prediction output and the real inclination residual are calculated by combining the verification data, and whether the calibration is qualified is judged according to the preset root mean square error threshold value; when the calibration is unqualified, sample points are supplemented or the smoothing parameter is adjusted to perform iteration.

The application discloses a kind of anti DC bias magnetic methods and current transformers based on magnetic permeability feedback compensation, comprising: the magnetic permeability of current transformer core is acquired in real time by magnetic permeability measuring unit;According to the relationship model of magnetic permeability and DC component established in advance, the DC component of invading current transformer is determined based on the magnetic permeability acquired;DC bias compensation unit generates reverse DC counter-biasing according to the DC component determined on compensation winding.The application realizes real-time monitoring and dynamic compensation adjustment to the magnetization state of transformer core by introducing magnetic permeability measuring unit and magnetic permeability feedback control, compared with traditional open-loop compensation or simple current feedback, can more accurately judge the saturation degree of magnetic core, adjusts compensation strategy in time according to the change of magnetic core state, effectively avoids compensation lag or overcompensation problem, improves the adaptability and measurement stability of transformer in complex current environment.

Provided is a multilayer ceramic capacitor having both AC voltage characteristics and DC bias characteristics. A multilayer ceramic capacitor (1) is provided with: a laminated body provided with an inner layer section (6) in which dielectric layers (4) and internal electrode layers (5) are alternately laminated, an outer layer section (7) disposed so as to sandwich the inner layer section (6) from the lamination direction (T), and a side gap section (8) disposed so as to sandwich the inner layer section (6) from the width direction (W); and external electrodes (3), which are respectively disposed on both end surfaces of the laminated body (2) in the longitudinal direction (L), and which are connected to the internal electrode layers. The average particle diameter Rd of ceramic crystal grains in the dielectric layer (4), the average particle diameter Rs of ceramic crystal grains in the side gap portion (8), and the average particle diameter Ro of ceramic crystal grains in the outer layer portion (7) satisfy the following relational expression (1): Rd < = Rslt; ro... (1).

This invention provides a method, apparatus, and system for compensating DC bias in a current transformer. The method includes: acquiring secondary-side current waveform data from the current transformer and determining the secondary-side current bias degree based on the waveform data; the secondary-side current bias degree measures the degree to which the secondary current waveform deviates from a preset time axis; determining the primary-side DC component based on the secondary-side current bias degree using a pre-established deviation relationship model between the primary-side DC component and the secondary-side current; the deviation relationship model recording the bias degree between the primary-side DC component and the secondary-side current on the corresponding time axis; and controlling a voltage-controlled current source in the current transformer to generate a reverse DC current to eliminate bias based on the primary-side DC component. This invention uses the secondary-side current bias degree to reflect the magnitude of the primary-side DC component, eliminating the need for additional measuring devices on the primary side and avoiding the cumbersome and difficult aspects of algorithm compensation in modeling, data processing, and algorithm writing.

This application relates to the field of microphone technology, and discloses a differential amplifier circuit and a desktop microphone. The circuit is used to amplify and process the differential audio signal of the desktop microphone. Its features include an input signal receiving and DC bias module, a differential transistor amplifier module, a fully differential operational amplifier module, a cross-feedback network module, a power supply and reference voltage module, and an output signal processing module connected in sequence. A common-mode negative feedback network for suppressing common-mode signals is provided between the emitters of the two corresponding symmetrical amplification paths of the differential transistor amplifier module. A cross-feedback network module is provided between the differential output terminal and the differential input terminal of the fully differential operational amplifier module to form an AC differential negative feedback loop. The power supply and reference voltage module includes at least two reference voltage units, which respectively provide DC bias for the differential transistor amplifier module and set the output common-mode level for the fully differential operational amplifier module.

The invention relates to an LCC-MMC extra-high-voltage direct-current transmission line fault restarting method and an extra-high-voltage direct-current transmission system, and belongs to the technical field of extra-high-voltage direct-current transmission. When a line fault is detected, the LCC converter station controls the fault current to a direct current reference value; the MMC converter station controls the sub-module voltage to a rated value, the outer loop control output is switched to the sub-module voltage controller output, the direct current bias part of the direct current voltage reference value is switched to the direct current controller output, and the direct current reference value is the direct current reference value; after the deionization time is over, the DC bias part of the MMC converter station rises to a reference value, and the constant current control is quitted at the same time; when the current converter port voltage is detected to be greater than the starting value, the sub-module voltage control is quitted, and the outer loop control output is switched to the direct current voltage controller output; and the LCC converter keeps a current control mode, and when the DC voltage is detected to be greater than a completion value, the LCC converter station switches the current reference value to a real-time current reference value, and the line fault restart is completed.

The invention relates to the technical field of electric energy conversion and control, and provides a bus voltage fluctuation suppression system and method based on voltage ANF orthogonal phase shift compensation. The system comprises a direct-current bus, a common direct-current bus open winding power converter electrically connected with the direct-current bus, a direct-current bias vernier reluctance generator electrically connected with the common direct-current bus open winding power converter, and a control loop. The control loop comprises a voltage self-adaptive notch filter detection module, a 0-axis current self-adaptive notch filter controller, a current distribution module, a dq-axis current regulator, a rotary / static coordinate transformation module, a pulse width modulation module and a voltage / current signal processing module. The method has the effect of improving the bus voltage quality and the operation stability of a power generation loop.

The invention discloses a capacitive inductive voltage sensor ultra-wideband response performance expansion circuit and a test method. According to the circuit, the ultra-wideband response capability is improved by cascading a hybrid integrating circuit, a high-pass filtering module and a voltage follower; the hybrid integrating circuit is formed by connecting a passive integrator (self-integrating to process low frequency and suppress high-frequency noise) and an active integrator (reducing high frequency in a differential mode) in series to cooperatively broaden the frequency band; the high-pass filter filters DC bias, and the voltage follower realizes impedance matching and signal isolation. Experiments prove that the hybrid voltage sensor can realize good waveform reduction on sinusoidal signals as low as 5Hz and steep waves as high as 10MHz, and the voltage division ratio is stable; for a 1kHz signal, after the circuit is inserted, the output phase is consistent with the input, the amplitude is accurately restored according to the designed voltage division ratio, the phase lead and the amplitude attenuation are effectively inhibited, the traditional frequency band limitation is broken through, and the circuit is suitable for an ultra-wideband voltage measurement scene.

The application provides a high-selectivity and simple-structure filter power amplifier and radio frequency integrated circuit, and relates to the field of power semiconductor devices.The application provides stable gate and drain bias voltages for the power amplifier transistor through a gate DC bias network and a drain DC bias network, and guarantees stable operation of the device.The input end and the output end impedance matching network are symmetrically arranged around the power amplifier transistor, both of which contain the same filter impedance transformer, and the layout is compact and simple, without additional independent filter module, effectively simplifying the circuit structure and improving the miniaturization level.Further, the filter impedance transformer is formed by cascading two λ / 4 parallel coupled microstrip lines and is matched with a λ / 2 open microstrip line, and based on the transmission line impedance transformation principle, the filter impedance transformer realizes fundamental real impedance matching, reduces signal transmission loss, forms transmission zero points in the stop band, and significantly improves the frequency selectivity.The overall circuit has high integration, excellent performance, and good engineering application and promotion value.

The application discloses a permanent magnet synchronous motor parameter identification method based on triangular wave injection and relates to the technical field of motor control. A triangular wave with a direct current bias is injected into the d-axis current of the motor. In the identification equation of the autoregressive least square algorithm, the current differential term in the voltage equation of the permanent magnet synchronous motor is considered. Two groups of input data with low linear correlation are combined into a new equation group. The parameters of the motor are divided into two sections, the new equation group is used for identification, and an identification result is output. The segmented autoregressive least square method parameter identification based on triangular wave injection can realize real-time identification of the resistance, inductance and flux linkage of the motor when the motor is in steady operation, so that the control performance of the double closed loop vector control of the permanent magnet synchronous motor is further improved.

A method for measuring DC bias aging characteristics of a multilayer capacitor includes applying a first poling voltage to a multilayer capacitor including a body having a dielectric layer including a plurality of dielectric grains and an internal electrode disposed alternately with the dielectric layer in a first direction, and an external electrode disposed on the body, maintaining the first poling voltage for a first period of time (t1), applying a DC bias voltage lower than the first poling voltage, maintaining the DC bias voltage for a second period of time (t2), and measuring saturated capacitance after the DC bias voltage is applied.

The application provides an E-FSR unit with an absorption and transmission mode controlled by an HPM and a direct current bias, comprising a plurality of periodically arranged E-FSR units, each unit being a five-layer cascade structure, and from top to bottom, the five-layer cascade structure is sequentially a first loss layer, a first air layer, a second loss layer, a second air layer and a frequency selection layer; the first loss layer, the second loss layer and the frequency selection layer each comprise a dielectric substrate, a metal pattern printed on the upper and lower sides of the dielectric substrate and a metal connecting column penetrating through the dielectric substrate; the frequency selection layer and the first loss layer and the second loss layer each are provided with a diode, the absorption and transmission mode is switched by applying a direct current bias voltage to the diode or driving the diode by using high-power microwave incidence, so as to meet the antenna mute stealth requirement, and the absorption and transmission mode is adaptively switched to an absorption band when high-power microwave is incident, so as to realize a protection function. The application solves the in-band strong scattering problem when the antenna is muted, has the advantages of dual-polarization characteristics, wide-band absorption and low insertion loss and the like.

The invention discloses a radiation and reflection integrated electromagnetic metasurface unit and an array thereof. The metasurface unit comprises a first dielectric substrate, a second dielectric substrate and a base structure formed by a PP layer located between the first dielectric substrate and the second dielectric substrate. A first metal layer is arranged on the upper surface of the first dielectric substrate, a metal floor layer is arranged between the first dielectric substrate and the PP layer, a second metal layer is arranged between the PP layer and the second dielectric substrate, and a third metal layer is arranged on the lower surface of the second dielectric substrate; by controlling the level of the direct-current bias line, the on-off state of the third PIN diode is further controlled to change the impedance matching state of the microstrip line and the gap, switching of the radiation reflection mode of the unit is achieved, and 2-bit reflection phase control is achieved in the reflection mode. The array comprises radiation and reflection integrated electromagnetic metasurface units which are arranged in an array mode, and each electromagnetic metasurface unit in the array can perform radiation and reflection mode switching by controlling the level of a corresponding direct current bias line so as to realize flexible regulation and control of electromagnetic waves; and the electromagnetic wave control capability can be well realized at 3.5 GHz, and the reflection efficiency is high.

According to the insulator surface charge cleaning method based on plasma discharge provided by the invention, the surface charge of the insulator can be actively, quickly and safely neutralized and cleaned through a composite discharge mode of pulse + direct current bias under the condition that equipment is not disassembled; the method comprises the following steps; equipment connection; setting and generating parameters of a composite waveform; high-voltage amplification; the plasma discharges to sweep charges; the discharge plasma device generates a high-pulse voltage electric field to reach gas breakdown field strength, a violent ionization reaction occurs, a large number of charged particles are further generated, and when superposed voltage acts during a pulse interval, the charged particles generated during the pulse interval migrate to the surface of the insulator under the action of the electric field generated during the pulse interval, so that the charged particles are formed. When residual charges in the discharge space are swept, migrated charges are used for neutralizing charges on the surface of the insulator, so that the charges on the surface of the insulator are swept; and cleaning is finished.

The invention discloses a power transformer multi-physics coupling simulation analysis method and a related device, and the method comprises the steps: constructing a corresponding geometric model and a multi-physics coupling model according to the obtained transformer data of a power transformer, and further determining a target simulation model; inputting a preset direct-current magnetic bias current into the target simulation model to simulate a direct-current magnetic bias state, and performing finite element analysis to obtain vibration displacement change distribution and sound pressure distribution; and according to the vibration displacement change distribution and the sound pressure distribution, determining the weak position of the power transformer influenced by the preset direct-current magnetic bias current. Therefore, accurate analysis and prediction of vibration and noise characteristics of the power transformer in the direct-current magnetic bias environment are realized by establishing a multi-physics field coupling model for analysis.

An electronic assembly heterogeneously integrates radio-frequency (RF) transistor chiplets into a wafer, and the chiplets have interconnections to wafer circuits. The assembly has at least one RF transistor chiplet having a chiplet circuit including a high-electron-mobility transistor (HEMT) or a heterojunction bipolar transistor (HBT). The wafer has at least one wafer circuit for the purpose of producing bias conditions that optimize performance of the HEMT or HBT. The wafer circuit includes first circuitry to provide a DC bias of the HEMT or HBT; or second circuitry configured to sense radio-frequency operating conditions of the HEMT or HBT. The electrical interconnects are between the chiplet and the wafer, and electrically connect the wafer circuit to the chiplet circuit.